Solar Power

Sahara Solar project to move forward at Munich meet

2009-07-10T09:43:00.000-07:00

BERLIN (Reuters) - A group of companies from Europe and northern Africa will meet in Munich on Monday to map out concrete steps for a series of large-scale renewable energy projects worth 400 billion euros ($560 billion) over 40 years.

They will launch a venture to explore the feasibility of harvesting solar thermal energy from the deserts of northern Africa and the Middle East to be used within the next decade or so in those regions and Europe.

Invited by German reinsurer Munich Re, executives from blue chip companies such as Siemens, E.ON, RWE and Switzerland's ABB along with firms from southern Europe and northern Africa will be at the inaugural meeting.

About 10 companies are expected to sign a memorandum of understanding setting up the Desertec Industrial Initiative.

Despite uncertainties associated with such vast multinational projects and concerns about political stability in the Mediterranean region, host Munich Re said the companies were eager to move forward with the next concrete steps.

"We believe the time is ripe for projects like this," said Alexander Mohanty, a Munich Re spokesman. "It's a great vision for the future. But we're not dreamers. This is the start of an industry initiative and we're looking for results.

"We're not just setting up a 'working group' to meet from time to time. The focus is on concrete results. The initiative will be doing lobby work, getting a dialogue going. The issue of the power price is important to be able to raise capital."

The European Union and German government are also firmly behind the projects. EU Commission President Jose Manuel Barroso and Chancellor Angela Merkel both expressly praised the idea behind Desertec at a recent Berlin meeting of energy executives.

Growing global efforts to slow climate change by reducing greenhouse gas emissions along with a projected increase in energy demand in the Middle East and northern Africa make the projects all the more attractive, its proponents say.

Analysts are eagerly waiting for details.

"I think it's a serious project, but it will take a very long time until there will be concrete news," said Commerzbank analyst Robert Schramm.

"The time schedule seems a bit overambitious. The technology is certainly there and it makes sense but there are political factors that need to be taken into consideration regarding the Sahara region."

HARNESSING SUN'S POWER

The Desertec Foundation has noted in six hours the world's deserts receive more energy than mankind consumes in a year.

The projects would use concentrated solar power (CSP) -- a technology that uses mirrors to harness the sun's rays to produce steam and drive turbines to produce electricity -- from the Sahara and deliver to markets locally and in Europe.

Using high-voltage direct current transmission lines there is only a minimal power loss of 3 percent per 1,000 kilometers.

Solar thermal is a well-tested technology from operation since the 1980s of an installation in the U.S. Mojave Desert as well as in Spain, but it is a more expensive source of electricity than fossil fuels.

Desertec officials hope the Sahara could be supplying 20 gigawatts of power -- the equivalent of 20 large conventional power plants -- by 2020 and one day deliver 15 percent of Europe's electricity, helping the EU meet CO2 reduction targets.

"After the founding we're planning to invite more companies to join in," said Michael Straub, head of marketing at the Desertec Foundation in Hamburg.

"At first we'll be studying which countries and which areas could be used for the first plants, and we'll also be studying the costs, the financing and other fundamental questions."

Straub said one project is already moving ahead; it would link power produced in Tunisia with users in southern Italy. He said it was possible it could be on line within five years.

Germany's Solar Millennium, which helped develop Spain's Andasol 1 solar thermal project, will also be at the Desertec meeting as is German solar technology company Schott Solar.

(Additional reporting by Christoph Steitz in Frankfurt; editing by Philippa Fletcher)

-- For Reuters latest environment blogs click on: blogs.reuters.com/environment/

($1=.7184 Euro)

Arizona Solar Power Plant Will Deliver Power Day and Night!

2009-06-08T20:58:00.000-07:00

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Written by Jack Moins

Monday, 08 June 2009

In 2013 the world will see the real future of solar technology. That's when the world's largest dispatchable power plant, the 290 MW Starwood 1 will start producing power day and night, on cloudy or sunny days.

Starwood 1 will showcase two critical future technologies. The first is power storage. Without storage, you will only have power when the sun is shining. And while that can work to a point, it will never power the whole world. We'll still need something to take care of the base-load, and that something, as of right now, is coal.

Different ideas have been cooked up for storing the power created by solar power plants – batteries, ultracapacitors, hydrogen generation, flywheels – but all of these are far from being affordable enough for large scale power needs. The alternative is to store power as heat before it's converted to thermal energy.

Fortunately, there is a fairly good and relatively inexpensive solution to thermal storage, one which Starwood 1 implements. Starwood 1's concentrating troughs feed heated liquid in large insulated molten salt tanks at 734 degrees Fahrenheit. When needed, these tanks will release steam, driving turbines at night or during cloudy weather.

The second big technology featured in Starwood 1 is concentrated solar power (CSP). CSP has seen commercial deployments since the 1980s, but has failed to dominate the industry. However, expect that to change as the maximum theoretical efficiencies of concentrated power designs are much higher than those of standard photovoltaics. CSP can be used to enhance thermal (as is done here) or to enhance photovoltaic technologies.

When completed Starwood 1 will cover 1900 acres of desert land. Unlike wind turbines there's a low risk of bird strikes, and the construction team is working to minimize the impact on ground-based local wildlife. Flash from the plant (burst of bright light when viewed from certain angles) is a concern, but given the remote location, this shouldn't prove a problem.

Locate approximately 75 miles west of Phoenix, the plant will produce enough power for 73,000 customers. The construction will also create 7700 jobs. The construction won't be cheap – the plant will cost $2.7B USD, but it should pay for itself and then some. If it can live up to its promise, which seems likely, expect more CSP plants and thermal storage installations to pop up across sunny remote areas of the U.S. southwest in the near future.

Via Green-Energy-News

No electric grid, no batteries: OGZEB house to run on hydrogen, solar power

2009-05-27T04:36:00.001-07:00



Publication Date:04-March-2007 09:00 AM US Eastern Timezone Source:Diane Hirth-Tallahassee Democrat.
What's a rectangle of dirt today may turn into an entirely energy self-sustainable house of the future by December. The Off-Grid Zero Emission Building or OGZEB is being built at Florida State University under the watchful eye of mechanical engineering professor Anjaneyulu Krothapalli, with the help of several other faculty and graduate students. "We are building a house that's not connected to the grid, completely run by solar during the day, and the house during the night will be running on hydrogen," he said. "That is unique. All the materials in the house are recyclable and green materials." "In about five years," was Krothapalli's estimation of how soon a house like this could be affordable and produced commercially. On Tuesday, there was a groundbreaking for OGZEB, which will be built just south of Tennessee Street near the north entrance to FSU's campus. The house will incorporate a way to make hydrogen using solar energy and an innovative fuel cell that both currently have patent applications pending. Hydrogen will be used for the big energy consumption in the house, such as heating, cooling and generating hot water. OGZEB's interior design is FSU-generated too, incorporating sustainable materials like bamboo floors. FSU scraped together $200,000 for the project, which is receiving support from private partners like Mad Dog Design and Construction. The FSU Sustainable Energy Science and Engineering Center is seeking more financial support for OGZEB. "We are building the building at cost," said Kristin Dozier of Mad Dog. "We really want the knowledge base to present to our clients."

SunRun PPA

2009-05-27T01:29:00.001-07:00

Sent to you by mchunkat via Google Reader:

SunRun PPA

via Cool Tools on 5/25/09

The cool tool here is creative solar financing. Solar-electric panels are pretty much a commodity, but still high priced. What's new is an innovative way for a homeowner to afford an expensive solar set up. Nine months ago I covered my studio roof with 5 kilowatts of solar panels financed by a solar company. We are generating about 85% of the electricity we use now. Here's how it works.

You sign up with a company that installs high-quality panels on your property for no money down. Zero dollars! On sunny days the panels make electrons which run your meter backwards. The quantity of panels are sized to cover about 80-90% of your current electric bill, so that you should be expected to pay the utility only 10-20% of what you pay now. In addition to the much smaller payment to your electric grid company you will also now pay the solar company a fee based on the number of watts you send into the grid. This is how they make money to cover the costs of installing the panels and their profit. The rates they will charge you per kilowatt will be less than the utility rates, so your total bill for electricity will be less each month. (Not zero, not half, but less.) Because the solar company makes money by how much electricity your panels produce they have a clear incentive to maintain the panels' performance and keep them clean and the inverters going. After 15-18 years, you own the panels and set up free and clear.

You could think of this as a lease-to-own option for solar panels, where the solar company's rents for electricity are cheaper than the utility grid's. Those cheaper rents are made possible in part by government solar subsidizes, which the solar company will claim on your behalf. But this is a business. While you may be generating 90% of your usage, because you are leasing the panels, your total combined bill will not be 90% less. It may only be 10% less per month. But since it costs you nothing or little up front, over 18 years that 10% adds up. In California, one company providing this zero down financing is SolarCity.

While I got a bid from SolarCity, we went with a slightly different deal from SunRun. Rather than zero down, we paid for half of the installation. That investment bought us a better rate for the electricity that we generate. In fact for the next 18 years we pay a fixed rate for electricity. The average California rate is expected to at least double, and we are projected to save $80,000 over 18 years. We could have gone all the way and bought the panels outright and then paid no lease. But we went with SunRun because this path requires either half, or no, down payment, and because SunRun specs out, installs, insures, owns and maintains the solar panels on our roofs. Also, they guarantee a certain level of output performance.

The actual rates that SunRun or SolarCity charge you depends on the particulars of your place -- the solar climate in your town, the pitch and orientation of your roof, potential shade, and local electric rates. Solar engineers use a really cool computerized tool (above) which takes a annualized panoramic to determine your solar potential. From this they can accurately predict your site's solar potential and lay out a design to maximize it by the hour. The image below was taken on the roof of my studio where our panels now lay.

Solar panels these days are low profile (you can't see ours from the street), modular, and require a minimum penetration into the roof. (The picture at the beginning of this review shows the panels being installed on our roof.) Our 28 panels made it through the rainy season with no problems. If there is a problem, the owner -- SunRun -- takes care of it. (There are escrow mechanisms should SunRun go out of business.)

The technical term for this kind of financing is a "solar power purchasing agreement" or a Solar PPA. Solar PPAs were first used for commercial properties -- huge flat roofs converted for collecting electricity. SunRun, SolarCity and a few others have adapted solar PPAs for home residential use. Right now SunRun operates in California, Massachusetts, and Arizona. SolarCity, California and Arizona. SunPower seems to have dealers in many states, though I have not used them. Coverage is being expanded rapidly so it's worth rechecking. Here is a PDF document answering the FAQ on "whether a solar PPA is right for you."

Like a lot of folks, we've wanted solar electricity for a long while but the significant up-front costs of installing it didn't seem to make sense. Zero dollars down makes sense. Half down and a fixed 18-year rate makes sense.

And watching my daily stats on the SunRun website, seeing the meter run backwards, really makes sense.

SunRun

SolarCity

Solar Power Partners
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World's Largest Solar Farm Project For Australia

2009-05-18T08:56:00.000-07:00

by Energy Matters

Perhaps still stinging from criticism on coal receiving the lion's share of clean energy funding in the budget last week, the Australian Government has highlighted a lofty goal - to build four solar farms that generate three times as much power as the world's current largest project based in California. The Rudd Government says it remains committed to ensuring 20 per cent of Australia's electricity comes from renewable sources by 2020.

Under the Government's $1.365 billion Solar Flagships plan, such a project would see the farms generating a combined 1 gigawatt of renewable energy generated electricity; the equivalent of an average sized coal fired power station.

The new solar farms will be built via a tender to be called later this year. The farms may consist of both solar thermal and solar panel (solar photovoltaic) technologies.

The successful companies and technologies chosen will be based on a competitive assessment, with an important criteria of industry development, including capacity to boost domestic manufacturing and future export potential.

In related news, the Government has also announced Australia will become a member of the International Renewable Energy Agency (IRENA).

Launched in January this year; Bonn, Germany based IRENA works on behalf of the renewables sector to promote the acceleration of renewable energy uptake worldwide. The organisation provides advice and support for countries, assists in the development of regulatory frameworks and the building of capacity. IRENA currently has 80 members.

The Rudd Government sees the membership of IRENA as a strengthening of Australia's role as a global leader in tackling climate change and the knowledge gained from operating the Solar Flagships program will contribute to the worldwide fight against carbon pollution.

Cooling with Solar Heat: Growing Interest in Solar Air Conditioning

2009-05-16T10:00:00.001-07:00

Sunny summer days are beautiful, yet in the office a hot day can be altogether stressful. Because productivity can suffer under such conditions, more and more buildings are being fitted with air-conditioning systems. This is where solar air conditioning comes in: The summer sun, which heats up offices, also delivers the energy to cool them. The thermal use of solar energy offers itself: Days that have the greatest need for cooling are also the very same days that offer the maximum possible solar energy gain.

The demand for air conditioning in offices, hotels, laboratories or public buildings such as museums is considerable. This is true not only in southern Europe, but also in Germany and middle Europe. Under adequate conditions, solar and solar-assisted air conditioning systems can be reasonable alternatives to conventional air conditioning systems. Such systems have advantages over those that use problematic coolants (CFCs), not to mention the incidental CO2 emissions that are taking on increasingly critical values.

Sorption-assisted air conditioning: collector system on the rooftop of Chamber of Commerce and Industry in Freiburg, Germany. Photo: Fraunhofer ISE.

The trend towards solar-assisted air conditioning is met by the organizers of the forum "Solar assisted Air-Conditioning of Buildings" at the convention Intersolar 2002: The German Association for Solar Energy (Die Deutsche Gesellschaft für Sonnenenergie (DGS)), the Fraunhofer Institute for Solar Energy Systems (Fraunhofer Institut für Solare Energiesysteme ISE), the Institute for Maintenance and Modernization of Buildings at the Technical University of Berlin (Institut für Erhaltung und Modernisierung von Bauwerken e.V. an der TU Berlin), and the Pforzheimer Solar Promotion Corporation (Pforzheimer Solarpromotion GmbH) are all offering a two-day international forum on the state of technology, the energy and economic aspects of solar cooling as well as the possible fields of application. Next to German companies, organizations from the entire world have registered including firms from Israel, Ghana, Spain, India, the Netherlands, Belgium, and Austria. This Solar-Report will briefly inform you over the possibilities and technology of solar air conditioning and will also cover economic aspects.

Basic structure of a solar air conditioning system

What is Solar Air Conditioning?

Should buildings be cooled with the help of solar energy, then water-assisted air conditioning systems or ventilation systems can be powered with heat that is made available by solar collectors. No long-term intermediate storage is necessary in months of high solar energy gain or in southern lands. The sun can, at least seasonally at our latitudes, provide a substantial part of the energy needed for air conditioning. Combination water-assisted systems and ventilation systems are also possibilities.

How does Solar Air conditioning Work?

The basic principle behind (solar-) thermal driven cooling is the thermo-chemical process of sorption: a liquid or gaseous substance is either attached to a solid, porous material (adsorption) or is taken in by a liquid or solid material (absorption).

The sorbent (i.e. silica gel, a substance with a large inner surface area) is provided with heat (i.e. from a solar heater) and is dehumidified. After this "drying", or desorption, the process can be repeated in the opposite direction. When providing water vapor or steam, it is stored in the porous storage medium (adsorption) and simultaneously heat is released.

Processes are differentiated between closed refrigerant circulation systems (for producing cold water) and open systems according to the way in which the process is carried out: that is, whether or not the refrigerant comes into contact with the atmosphere. The latter is used for dehumidification and evaporative cooling. Both processes can further be classified according to either liquid or solid sorbents. In addition to the available refrigerating capacity, the relationship between drive heat and realized cold energy (coefficient of performance; COP) is also an essential performance figure of such systems (see Table 1 at end of article).

Absorption Refrigeration Machines

In Germany, closed absorption refrigeration machines with liquid sorbent (water-lithium bromide) are most often operated in combination with heat and power generation (cogeneration) (i.e. with block unit heating power plants, district heating), but can also be assisted by vacuum tube solar collectors (operating temperature above 80 °C). With a single-step process the COP is 0.6-0.75, or up to 1.2 for a two-step process. A market overview is available from the Consortium for Economical and Environmentally Friendly Energy Use (Arbeitsgemeinschaft für sparsamen und umweltfreundlichen Energieverbrauch (ASUE)).

Adsorption Refrigeration Machines

Closed processes with solid sorbents work with so-called adsorption refrigeration machines (operating temperatures 60° - 95°; COP = 0.3 - 0.7). Solar energy can easily be used in the form of vacuum tube or flat plate collectors. A pilot system used for a laboratory's climate control at the University Clinic of Freiburg is fitted with tube collectors; the Fraunhofer ISE also took part in its scientific conception. The refrigerating machine is composed of two adsorbers, one an evaporator and the other a condenser. An adsorber chamber takes up the water vapor, which is transformed into the gas phase under low pressure and low temperatures (about 9°C) within the evaporator. Granulated silicate gel, well known as an environmentally friendly drying agent, then accumulates it (adsorbs the water vapor). In the other sorption chamber the water vapor is set free again (the chamber is regenerated or "charged") by the hot water from the solar collector (about 85°C). The pressure increases and at the temperature of the surroundings (30°C) the water vapor can be transformed once again into a fluid within a cooling tower (condensed). Through a butterfly valve the water is led back into the evaporator and the cycle begins from the beginning. Both the condensed water (low temperature) and the sorption heat (high temperature) are discharged.

Main components of the system at the University Clinic of Freiburg: Adsorption refrigeration machine (left) and solar thermal system (right).

The thermal operating power for this adsorption refrigeration machine is produced by vacuum tube collectors with a surface area of 170 m². Additionally, heat storage tanks improve the use of the solar heat. A cold storage tank functions as a buffer during short-term demand fluctuations. During colder times of the year, the solar energy heats the air inflow thereby reducing heating costs.

Sorption-Assisted Air Conditioning

Although the process of sorption-assisted air conditioning has been known for a long time, it has only been used in Europe for about 15 years. In principle, under middle European climate conditions, sorption-assisted air conditioning systems can be operated everywhere an air conditioner is wanted, for example in ventilation control centers. Their economical operation is then possible if cost-effective heat energy is available, i.e. from cogeneration plants, rather than from over loaded district heating systems. New heat sources, offering much promise, are solar thermal systems. Open sorption-assisted air conditioning systems are fresh air systems, that is they dry the outside air through sorption, pre-cool it with a heat reclamation rotor and finally cool it to room temperature through evaporation-humidification. The main principle of sorption-assisted air conditioning is shown in the graphic. The solar energy is used to dehumidify the sorbent.

Basic structure of the process of sorption-assisted air conditioning.

The most important steps of the process are:

1-2 Sorptive dehumidification of outside air with simultaneous rise in temperature through the freed adsorption heat
2-3 Cooling of the air in the heat reclamation rotor in the countercurrent to the exhaust air
3-4 further cooling of air through evaporation-humidification; the air inflow to the building has a lower temperature and less water vapor than the outside air
4-5 Heating of the air and if necessary addition of water vapor
5-6 Lowering of building's exhaust air temperature through evaporative cooling in the humidifier
6-7 Heating of exhaust air in the countercurrent to the air inflow in the heat reclamation rotor
7-8 Further heating of the exhaust air through external heat sources (i.e. solar thermal system)
8-9 Regeneration of the sorption rotor through the desorption of the bound water

At present, systems with rotating sorption wheels (sorption rotors) are mostly in use. The sorption wheel has small air channels that create a very large surface contact area, which has been treated with a material that easily takes up moisture, such as silica gel. The inflow air is dehumidified in one of the two sectors of the rotor and heated through the adsorption process (the exhaust air serves to dry the rotor). Finally, the inflowing air is cooled down in a heat reclamation rotor. The heat transfer here is made possible through the contact between the air and the rotor material. The last step in cooling the inflowing air is with conventional evaporation humidification.

How well do Solar-Assisted Air Conditioning Systems Operate?

Scientists of the Freiburg Fraunhofer Institute for Solar Energy Systems ISE (Freiburger Fraunhofer Instituts für Solare Energiesysteme ISE) tested solar assisted air conditioning systems for a study of the International Energy Agency (IEA) in the context of the TASK 25 "Solar-Assisted Air Conditioning of Buildings". Detailed descriptions and results of the compared systems can be gathered from the study's conclusion [1]. Year simulations of five variants of a solar-assisted system for air conditioning were conducted and compared to a conventional system for different climates (Trapani/Sicily; Freiburg and Coenhagen).

Energy Balance

Without the use of solar energy, thermally powered climate control raised the primary energy use (thermal and electrical) for all of the tested locations. The reason for this is the lower operating numbers of this process in comparison to electrically powered compression refrigeration machines.

Whether absorption or adsorption refrigerating machines are used, a solar-covered share for cooling of 30 % (Freiburg) and almost 50 % (Trapani) is required to affect a primary energy savings. The solar-covered share for cooling is the portion used for cooling during the summer that comes from heat made available by the solar thermal system. With coverage shares of up to 85 %, the primary energy use can be decreased by over 50 % compared to the conventional reference system. The results were ascertained from an example reference office building and can therefore not simply be applied to other cases or buildings.

In Trapani the sorption assisted air conditioning, in combination with a compression refrigeration machine, led to a small primary energy savings with a solar coverage share of 30 %. If the sun delivers 85 % of the heat for the air conditioning, then just about 50 % of the primary energy can be saved. In this case there are two apparent positive aspects: the sorption-assisted air conditioning can effectively be used for air dehumidification and additionally it can achieve relatively good overall efficiency.

Photo: Sorption-assisted air conditioning system in Portugal.

Cost Effectiveness

Although over 20 systems that use thermal solar energy to air condition buildings and that can be technically and economically assessed have been installed in Germany, there are still a number of obstacles to be overcome when it comes to the implementation of solar-assisted air conditioning. In the twelve countries taking part in the TASK 25 of the Solar and Heating Program of the IEA, experience with about 30 systems has been gained and currently 10 systems are being tested as a part of a demonstration program. Such pilot and demonstration programs are still necessary so that cost reductions become possible and so that relevant energy savings can be assured. Standardized programs, matured concepts and the development of components are starting points that can contribute to improved cost effectiveness and wide applicability of solar-assisted air conditioning.

Because solar cooling is based on thermally driven processes instead of the normal electrical cold production, the costs for the used heat plays a central role: a fundamental problem arises from the inherently higher costs of solar heat compared to heat energy produced by fossil fuel systems or waste heat. Experts at the Fraunhofer ISE expect no economical advantages of the solar air conditioning in this respect. Their use becomes interesting if favorable requirements for a high output of solar heat are present and if the system also delivers energy for heating. The cost of electricity could also pose an argument for solar cooling: The thermally powered cooling process requires only a fourth (absorption/adsorption) or half (sorption-assisted air conditioning) of the electrical power required by the conventional reference system.

The ISEs comparative testing showed that during the process the sorption-assisted air conditioning connected to a conventional machine (compression refrigeration machine) represents the most promising system combination, at least for a Mediterranean climate. The sorption-assisted air conditioning produced the lowest costs at all locations, while the adsorption machines were the most expensive solution. The scientists at the Fraunhofer ISE see a chance for sorption-assisted air conditioning in the cooperation between German facilities and companies that have gained experience with the operation of sorption processes for climate control and large solar thermal systems. Using this know-how, especially in Mediterranean regions, a gap could be found in the market.

Process	closed		open
Coolant circulation	closed refrigerant circulation systems		open refrigerant circulation systems (in contact with the atmosphere)
Process baic principle	cold water production		air dehumidification and evaporative cooling
Sorbent type	solid	liquid	solid	liquid
Typical material systems (refrigerant/sorbent)	water- silica gel ammonia- salt*	water-water-lithium bromide, ammonia- water	water-silica gel water- lithium chloride- cellulose	water- calcium chloride, waterlithium chloride
Marketable technoloy	adsorption refrigeration machine	absorption refrigeration machine	sorption assisted air conditioning	-
Marketable output [kW cooling]	adsorpzion refrigeration machine [50 - 430 kW]	absorption refrigeration machine: 35 kW - 5 MW	20 kW - 350 kW (per module)	-
Coefficient of Performance (COP)	0.3 - 0.7	0.6 - 0.75 (one step) <1.2 (two step)	0.5 - >1	>1
Typical operating temp.	60 - 95°C	80 - 110°C (one step) 130 - 160°C (two step)	45 - 95°C	45 - 95°C
Solar technology	vacuum tube collector, flat plate collector	vaccum tube collector	flat plate collector, solar air collector	flat plate collector, solar air collector

*still in development

Table 1: Overview of processes for thermally powered cooling and air conditioning

Material and Pictures: Fraunhofer ISE: Solarserver Editor: Rolf Hug. We thank Dr. Hans-Martin Henning and Diplom Engineer Carsten Hindenburg for their friendly support.

EFFECT OF PARABOLIC TROUGH SOLAR COLLECTOR ORIENTATION ON ITS COLLECTION EFFICIENCY

2009-05-14T10:42:00.001-07:00

Authors: A. S. Hegazy ^a; M. M. El-Kassaby ^b; M. A. Hassab ^b

Affiliations:	^a Mechanical Power Engineering Department, Monoufia University, Egypt
	^b Mechanical Power Engineering Department, Alexandria University, Egypt

DOI: 10.1080/01425919508914275

Publication Frequency: 4 issues per year

Published in: International Journal of Sustainable Energy, Volume 16, Issue 3 January 1995 , pages 173 - 183

Subjects: Alternative & Renewable Energy Industries; Alternative Fuels; Energy Conservation; Green Buildings; Power & Energy; Power Electronics; Renewable & Sustainable Energy; Solar Energy; Sustainable Engineering;

Formats available: PDF (English)

Previously published as: International Journal of Solar Energy (0142-5919) until 2003

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Abstract

Parabolic trough solar collector PTC is often oriented with its axis horizontally in the North-South or East-West direction. However, it may be set in a position where its axis makes an angle Ψ with the south direction. The main objective of the present work is to study the effect of this angle on the collection efficiency. An algorithm for calculating the collection efficiency for any time period has been developed. The results obtained by using this algorithm by using this algorithm show that the maximum daily collection efficiencies η_c,d all over the year are obtained for the N-S orientation at sites having latitude angles Φ ≤ 15°. For latitude angles Φ > 15°, η_c,d are much higher in summer days than in winter ones for N-S orientation. In the case of orienting die collector with an angle 70° lt; Ψ ≤ 90°, η_c,d are higher in winter days than in summer ones This orientation is preferable to obtain almost constant output of PTC through the whole year. The results show also that a trough oriented with an angle of 70° from N-S direction has almost a constant daily collection efficiency all over the year in order of 82% when considering the reflectivity of the collector surface equal to unity. Also, the effect of orientation on yearly collection efficiency η_c,y are minor at latitude angle Φ between 30° and 40° while the effect of orientation becomes important outside this range.

Keywords: Parabolic trough collector; Collector orientation; Collection efficiency; Latitude angle; Incident angle

Making the desert bloom with solar flower power

2009-05-13T19:35:00.001-07:00

By Rachel Neiman May 13, 2009

Rising up, like a mirage in the middle of the desert outside Eilat, is a giant yellow tulip in whose heart lies a massive crystal. Surrounding it: a field of mirrors that slowly move back and forth, following the sun.

Hallucinatory though it may sound, this is no mirage. The tulip is actually a solar tower with an aperture that directs sunlight into a solar receiver that drives a high-powered turbine, and the 30 tracking mirrors below are called heliostats.

It's an ambitious project initiated by Israeli company AORA to construct the world's first solar-thermal powered gas turbine station. The plant, with its distinctive 30-meter high tulip-shaped tower, is now nearing completion at Kibbutz Samar in Israel's southern Arava region.

AORA, of Israeli EDIG group, is a developer of applied ultra-high temperature concentrating solar power (CSP) technology. The breakthrough of CSP is that it can power a 100kW gas micro-turbine; other solar technologies currently available can only power much larger steam turbines. AORA says it is the worlds' first company to commercialize the use of a solarized gas turbine engine.

The government recently showed support when Minister of National Infrastructures, Binyamin Ben Eliezer signed AORA's license provide solar electricity to the national grid -- the first such license to be granted by Israel to solar-thermal technology.

Being able to run the equivalent of a jet engine on solar power, means the system is efficient at far smaller power blocks, Yuval Susskind, COO of AORA, explains to ISRAEL21c. This enables smaller scale projects that require less land and shorter towers (30m vs. 70-120m and more), and which are easier to build, finance and operate.

"Israel has all the climate conditions, but we don't have huge available tracts of land. AORA is the first to bring the size of a solar field down to something like a soccer pitch or a baseball diamond," says Susskind.

Business looks bright - abroad
The installation at Samar will be the model for many more to come, says Haim Fried, CEO of AORA, and will include the framework for selling power to the national grid over a long-term period.

The company expects to begin power generation any day. Once it begins generating power, Fried says, the Samar unit will provide 100kW electric power to the grid, as well as 170kW thermal power - enough to supply 50 households at an average of 2kW per household. "That's the average use in Israel. The US is a bit more," he explains.

Fried notes that selling power to the local grid close to the customer base is more efficient because there is no need to step up and down voltage, as is done when transmitting power from a central power station. By generating locally, the power is fed in low voltages, via the local distribution grid, for standard domestic use in the home. It also relieves the load on the high voltage distribution grid.

Location is key, he adds because AORA's installations require direct radiation. "The set up cost is the same in the Arava or Tel Aviv but for the same investment I get more direct sunshine at Samar, so I'll get more power out of it."

The company's business plan has two profit centers: in Israel it will sell power to the national grid through partnerships. Outside Israel, the company will set up joint ventures with local partners to build solar power stations and sell clean energy to the grid.

Costs haven't been finalized yet, but Fried says installations will be competitively priced and estimates that AORA will become profitable after selling 20 units.

"We're also probably going to do a joint venture in Spain," he adds. "We want to do more in Israel but there's a problem with the feed-in tariffs, which are too low. In Spain, they pay 29.9 eurocents, which is much more favorable. If Israel doesn't change the rates then we'll have to do more business outside."

Sunny technology
The AORA system is hybrid, meaning it can run on solar, as well as almost any alternative fuel, including biogas, biodiesel and natural gas. Being located in an agricultural community such as Samar, Susskind points out, means ready access to unlimited amounts of biogas, courtesy of the kibbutz cowshed. "So it can run on sunshine during the day, biogas at night and be operational 24 hours a day," he says.

The system is also modular and scalable; more base units - each comprising a tulip tower and 30 heliostats on a half-acre of property - can be added as demand grows.

Modularity enables each unit to be located independently with no need for one large, flat, contiguous expanse of land. Strung together, the units can form a utility-scale power plant. Being modular also means greater reliability, the company states, as servicing a single base unit does not require a complete shutdown.

The key components of AORA's Power Conversion Unit (PCU) are the micro-turbine and the solar receiver, whose technology resulted from collaboration with the Weizmann Institute and Rotem Industries.

The patented receiver uses the sun's energy to heat air to a temperature of 1,000 degrees Celsius and direct this energy into the turbine. The turbine then converts this tremendous thermal energy into electric power.

The solar receiver and some other key components are proprietary technologies and will always be manufactured in Israel, says Fried. However, other components, such as the tower and heliostats, are made of simple materials and can be manufactured wherever a base unit is to be set up according to AORA's specifications.

The company unveiled the Samar project in February, at the annual Eilat-Eilot Renewable Energy Conference. "The response was very positive - which is a great compliment because of the high professional level there," says Fried.

"Greentech has to look good"
AORA's tulip is painted bright sunny yellow. Susskind says this was because the dusty red of the Arava hills overpowered the gold color. "One reason for selecting Samar was its proximity to the highway. I want every kid to see this tower when they're heading for a family vacation in Eilat," he says.

The company hired architect Haim Dotan to design the tower. "We didn't think we could afford it but we met with him, and told him about our vision: that there would be many towers like this all over the world. He was so excited about the project that he said he would do it in any case. He said it would make the desert bloom - that's why it's in the shape of a flower. He loves the desert and wants it to be beautiful."

AORA also has a vision of setting up a roadside attraction for tourists: an alternative energy education center that will showcase not just the company's own technology, but other cleantech being developed and tested in the region as well. The company has already been in talks with the regional council, which is interested in the project.

After the Samar facility is completed, AORA plans to expand into larger scale power generating plants of 5MW and more. "By late 2009, we plan on setting up our first international installations in strategic markets," says Fried. These include the Mediterranean, southern Europe, Australia, California, Arizona and the US Sun Belt states. At a later stage, the company aims to enter the African market. "We view China - where we already successfully constructed and operated a pilot unit - Africa and other remote regions as the true market for the AORA system," says Fried.

Concentrating Solar Energy Technologies Explained

2009-05-13T05:33:00.001-07:00

May 12, 2009

by Mike Taylor, Director of Research and Education, Solar Electric

Q: What are the different types of concentrating solar energy technologies? Why are they limited to the southwestern United States? -- Bertha Z., Berea, KY

There are two main types of concentrating solar energy technologies: concentrating photovoltaics (CPV) and concentrating solar thermal (CST). Together they are commonly referred to as concentrating solar power (CSP), although sometimes CSP is used interchangeably with CST.

1. Concentrating photovoltaics (CPV) uses lenses or mirrors to focus or increase the sun's light on a photovoltaic solar cell or panel. This technology includes both a low-concentration approach, which increases the sun's magnification by less than 5 "suns," and high concentration approach, which can increase the magnification by hundreds of suns. High-concentration CPV uses focusing lenses to concentrate the sun's rays on a single, high efficiency solar cell that is very small, on the order of 1-centimeter square.

When you hear about a new world record for PV efficiency that exceeds 40%, it is generally this type of technology they are utilizing. CPV's "better mousetrap" uses less photovoltaic material (tiny, high efficiency cells), concentrates the sun and increases performance, hopefully enough to offset any additional costs.

2. Concentrating solar thermal (CST) technology uses mirrors to focus the sun's light on a heat capturing point, the heat from which can then be either used directly or converted to electricity. The three basic designs of CST are troughs, towers and dish-engine systems.

Troughs are set-up in large horizontal fields that contain long loops of piping (many kilometers for large installations). The pipes collect the 600+ degree (F) heat from light reflected off mirrors that concentrate the sunlight in a line on the pipes. Troughs have the longest proven operating history and the least number of unknowns for CSP technology project development.

Towers use a mirror field that is set-up around the tower. The mirrors focus sunlight on a heat receiver at the top that collects the heat and transfers it to piping inside the tower where is it circulated and used to make electricity. The design minimizes the field of piping to the vertical tower height to a few hundred meters and can reach temperatures in excess of 1000 degrees (F). While currently there are very few commercially operating tower installations, based on announcements, this technology may grow rapidly.

Dish-engine systems look like satellite dishes and focus light on a Sterling engine mounted on an arm in front of the mirrors. Each dish-engine is an autonomous generator—unlike the other CSP technologies that use a central power plant design—and utilizes a temperature and pressure difference to produce kinetic movement inside the engine, which is then converted to electricity.

An interesting development for troughs (and possibly towers in the future) is the interest on the part of utilities in "hybrid-solar power plants," which include the pairing or retrofitting of natural gas or coal power plants with the thermal input or boost from CSP.

The one thing that is common among the different kinds of concentrating solar power technologies is that unlike traditional photovoltaic panels, they need "direct normal" solar radiation, i.e. sunlight that can cast a shadow. A certain percentage of solar radiation is made up of diffuse or scattered light, caused by clouds, humidity or particulates. Solar resource measurements are reported as either "direct" normal radiation (no diffuse light) or total radiation (diffuse + direct).

The southwest has the highest percentage of "direct normal" radiation of nearly anywhere in the world, making this one of the best regions for development of CSP. However, there is one CSP trough project in Florida—a hybrid CSP plant that will augment a natural gas plant—and a number of trough and tower projects in Spain. CSP will work in both areas, but performance will be commensurately reduced based on the direct normal radiation profiles.

The CSP industry is growing fast in Spain and the United States, and SEPA is tracking over 5,000 MW of new project announcements that are slated for development over the next five years. Not all of them will be built—permitting, financing, technology and other factors need to fall into place first—but the industry is poised for rapid growth regardless of any individual project's outcome.

http://www.renewableenergyworld.com/rea/news/article/2009/05/concentrating-solar-energy-technologies-explained

HelioDynamics Commissions Solar Concentrator Project In California

2009-05-13T05:24:00.001-07:00

SI Staff, Tuesday 12 May 2009 - 10:21:36

International energy integrator EnergyMixx AG says that its wholly owned subsidiary, HelioDynamics, has successfully completed commissioning of its latest solar project.

The project, which incorporates HelioDynamic's linear Fresnel solar concentration technology, provides energy for air conditioning on the Southern California Gas Co. Energy Resource Center located in Downey, Calif. The system is part of a comparative program to use heat generated by the sun to power an absorption chiller that feeds cold water to the air conditioning loop.

The HelioDynamics solar concentrator is available for the generation of industrial-grade heat at temperatures in excess of 185 degrees C. It uses EnergyMixx-developed Technology, employing simple flat-glass mirrors held within a lightweight, low-cost but robust aluminum frame.

SOURCE: EnergyMixx AG

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How to Make the Green Revolution Work

2009-05-10T19:31:00.000-07:00

By JIM MCTAGUE

The best way to go green: carbon taxes, cap-and-trade -- and white paint.

IF THE NATION IS GOING GREEN, THEN CONGRESS AND THE administration should go for a jolting, life-altering transition in a logical, cost-effective manner. However, the evidence so far is that logic will play second fiddle to fashion.

Scientist-businessman Arnold Leitner points to tax subsidies for hybrid cars and photovoltaic systems as being especially inefficient applications of tax dollars to alter consumer behavior.

"Right now, the entire environmental discussion is driven by the affluent do-gooder who want to save the planet," he says. "The result is a complete misallocation of our tax money."

Government programs supporting weatherization and white paint make sense, he says; they'd provide more bang for the buck in helping utilities meet peak demand than would support for expensive, relatively inefficient photovoltaic systems.

And funding light-rail systems powered by clean energy is also going to have greater impact than giving tax breaks to people who buy hybrids, which still require gasoline.

Leitner, who was reared in Germany, holds a doctoral degree in physics from the University of Colorado and runs a highly innovative alternative-energy outfit called SkyFuel.

LEITNER ASSERTS THAT APPLYING WHITE paint to the roofs of commercial buildings in warm and sunny places like Los Angeles would cut their air-conditioning costs by 15% to 20%.

"We now consume twice as much energy in this country as we have to, because we are wasteful and not smart," he says. He also recommends widespread use of roof-top solar hot water systems to significantly cut electric demand.

If it sounds as though Leitner has an axe to grind against photovoltaics (PV), he does and he doesn't.

He spent his early years as a physicist trying to develop PV film -- until government funding for the program was cut. He went on to research superconductors, elements that conduct electricity with little resistance. Now his company, based in New Mexico, may eventually go public; it competes against the PV industry for business and tax dollars.

Leitner is now hawking a technology called parabolic-trough solar collection. The trough system generates electric power by using highly reflective, mirrorlike polymer-based film to concentrate sunlight and heat a conducting fluid above 700 degrees Fahrenheit. The fluid, in turn, makes the steam that drives a plant's generators. Enough of that superheated water can be stored by a utility in an insulated container the size of an oil tank to produce electricity 24/7. By contrast, PV converts sunlight into power and has more limited storage capacity, so it is used in smaller applications.

Like photovoltaic power and other forms of green energy, Leitner's industry could not exist without government subsidies such as tax breaks and research credits. (He says that trough systems require a subsidy of 50 cents per kilowatt, versus $3 per kilowatt for PV). It is impossible in today's marketplace for renewable energy to compete against coal, as long as the cost for putting emissions into the atmosphere is free, Leitner adds.

SO HOW DOES THE GOVERNMENT GET its citizens to go green?

"If you want to change behavior, then you only get there when it hurts," he says. This means setting a floor price for carbon -- a base cost of doing business that shows the real cost of using carbon in the various things we do. The tax might have to be high enough to raise the cost of a barrel of oil back over $150. Last time oil hit that mark, gasoline shot up to $4-a-gallon (or higher in many regions) and commuters abandoned their cars for public transportation.

Leitner also says the government must avoid establishing a "renewable-energy portfolio" dictating the percent of power than must come from various sources like solar and wind. "Let the market respond to the price signal," he urges Congress.

Leitner favors a regime that would have a cap-and-trade system for registered, fixed-place emitters and a simple carbon tax for the rest of us.

The public will not stand for such a tax if it does not perceive that it's getting something in return. He suggests using the proceeds to fund "sacred programs" like benefits for veterans, something no future politician in his right mind would consider rolling back.

Leitner sees a payoff for our children and grandchildren. Although the start-up costs for solar-trough and wind power are high, longer term, the cost of producing energy in these systems is practically free, he says. He points to the big dams built by the U.S. in the 1930s. They were paid off long ago, but are still operating and producing power at nearly zero cost.

E-mail: jim.mctague@barrons.com

Hybrid Air-Conditioning System Reduces Energy Use 60%

2009-05-06T21:15:00.000-07:00

(May 5, 2009) -- DuCool is launching the DuHybrid air-conditioning system which is powered by solar thermal energy or electricity to reduce the energy required for cooling by up to 60% compared to standard air conditioning. The DuHybrid system combines desiccant dehumidification with evaporative or geothermal cooling to eliminate the need for conventional mechanical cooling. It utilizes solar thermal energy when available and automatically switches to electric power when needed. The DuHybrid system can also be integrated with a cogeneration system and can be powered by other renewable energy sources or waste heat.

The DuHybrid system operates in one of two modes. The renewable energy mode is the default mode of operation. Based on the application, in this mode the unit can generate over 20 TR (tons of refrigeration) of cooling and dehumidification using renewable energy sources such as solar thermal and geothermal water. In the electric mode of operation an embedded compressor is activated to enable efficient cooling and dehumidification by utilizing the waste heat of the compressor as an internal energy source. The DuHybrid system can be supplied in one of the three configurations, 1400CFM, 2400CFM and 3400CFM, that cover a broad range of commercial and industrial needs for air conditioning and dehumidification.

Additional benefits of the DuHybrid system include the ability to control humidity and temperature independently (variable sensible heat ratio). This guarantees that the required conditions, both temperature and humidity, are achieved in the most energy efficient way. The DuHybrid's liquid desiccant cooling process eliminates 91% of the bacteria in the air in a single pass and removes over 80% of all particles larger than five microns including allergens such as pollen, dust and other airborne particles. These air scrubbing qualities are inherent to all of DuCool's cooling and dehumidification systems.

About DuCool
DuCool's systems cool, heat, dehumidify, disinfect and clean the air while providing independent control of temperature and humidity. DuCool's solutions are powered by renewable energy sources such as solar thermal panels, geothermal water or available low grade waste heat, providing considerable savings to commercial and industrial users. DuCool systems utilize a patented liquid desiccant process for dehumidification and air conditioning that is considerably more efficient and effective than other air conditioning and /dehumidifying solutions. DuCool systems can be configured as a standalone solution or they can be coupled with existing conventional systems to provide a superior energy saving solution.

Starfish reinvests in solar company

2009-05-06T21:14:00.001-07:00

Joins managers to set up equity funding facility

By Alice Uribe
Thu 07 May 2009

Starfish has joined with five other managers to establish an equity funding facility for Ausra.

Venture capital manager Starfish Ventures has reinvested in California-based solar thermal energy company Ausra.

The Melbourne-headquartered manager is part of a group of five that has ploughed $25.5 million into an equity funding facility for the company.

Other members of the group are Al Gore-founded Generation Investment Management, Ausra founding investors Khosla Ventures and Kleiner Perkins Caufield & Byers, and Kern Partners.

Funds from the equity facility will be available to Ausra for acceleration of the company's solar thermal energy equipment supply business.

Ausra said the group had committed the funds to support global expansion opportunities for existing power generation and industrial steam applications.

Starfish Ventures has had a number of institutional investors, including Westscheme and MTAA Super.

The Secret to Low-Water-Use, High-Efficiency Concentrating Solar Power

2009-05-03T21:21:00.001-07:00

Joe Romm
April 30, 2009 12:08 PM

Many readers have expressed interest in learning more about the water consumption of concentrating solar power and how measures to reduce it might impact system efficiency and cost. After my recent CSP post, "World's largest solar power plants with thermal storage to be built in Arizona," Michael Hogan wrote in the comments (here) about a low-water-consuming cooling system he had experience with. I asked Hogan, a long-time power industry executive and currently the Power Programme Director for the European Climate Foundation (bio here), to write a longer piece for Climate Progress. Here is what he put together, with links and figures (click to enlarge).

EXECUTIVE SUMMARY: If concentrating solar power ("CSP") is a core climate solution, indirect dry cooling systems (also known as "Heller" systems) will be a crucial enabling technology, since large-scale CSP will be located in desert regions. US power companies have long favored direct dry cooling systems for fossil plants, probably because of the visual impact of Heller systems. But Heller systems have long experience in certain regions and will probably play an important role in the success of large-scale CSP. This is due to their higher efficiency, smaller footprints, quieter operation, lower maintenance, higher availability, and more flexible site layout. Heller systems can reduce water consumption in a CSP plant by 97% with minimal performance impact. The height of the cooling towers should be less of an issue in remote desert locations, especially since the central tower in power tower facilities will be of comparable height.

Concentrating solar thermal power plants ("CSP") have been identified a number of times in Climate Progress as a core climate solution due to their almost unique potential to replace coal as the dominant supplier of baseload and/or firm dispatchable capacity to the world's power grids. It is said that CSP could represent 3 of the 12-14 wedges in the 450ppm solution –- 20-25% of global mitigation potential. I concur wholeheartedly with that view, and I applaud CP for its efforts to educate readers on the singular challenges of eliminating coal-fired power production at scale. But if CSP is a core climate solution, dry cooling technologies, and in particular Heller systems, will be a crucial enabler (see note at the end regarding the status of the name "Heller" system).

One of the concerns often cited about CSP is water consumption, particularly because the technology's reliance on direct normal insolation means that it is most economically located in desert regions. Because most CSP systems rely on Rankine cycle steam turbine-generators to produce electricity, they face the same requirements as fossil-fired power plants for condensing large volumes of saturated steam back into boiler feedwater. (Parabolic dish systems use Stirling or Brayton engines to produce useful energy, each of which has its own advantages and disadvantages) Where an abundant and cheap supply of water is available, the most efficient way to accomplish this is by evaporation (or "wet cooling"), which is what produces the large plume of water vapor one often sees rising from power stations. Convective cooling using ambient air ("dry cooling") requires higher capital costs and can reduce plant performance, and thus planners of fossil plants have sought to locate them close to adequate supplies of cooling water whenever possible.

In the desert areas where CSP will thrive, the consumption of large amounts of water by conventional wet cooling systems is clearly unsustainable. Dry cooling alternatives will be required, and CSP will have to demonstrate its commercial viability despite the capital cost and performance penalties this will entail. Fortunately this is an eminently manageable problem.

[Acronyms: "LEC" = levelized electricity cost; "O&M" = operation & maintenance]

Deutsches Zentrum fur Luft- und Raumfahrt e.V. ("DLR"), a German government research agency, presented a study in 2007 comparing a particular dry cooling technology, the Heller system, with wet cooling for CSP plants in Spain and in the California desert (see figures above). Water consumption was reduced by 97%, and the performance impact was quite minimal. Indeed the impact on performance in the higher desert temperatures of California was overwhelmed by the benefits of better annual insolation. They also noted that the potentially negative impact of high daytime temperatures is mitigated by the use of thermal storage, which uses energy collected during peak daytime insolation to produce electricity when temperatures are considerably lower. One interesting aspect of the DLR study was their focus on Heller systems over more familiar (at least in the US) direct dry cooling systems, and that is worth a closer examination.

Two basic types of dry cooling systems have long been employed where necessary -– "direct" air cooling (usually called an "air-cooled condenser" or "ACC") and "indirect" air cooling (often referred to as the "Heller system", after Laszlo Heller, the Hungarian thermodynamics professor who pioneered this approach in the 1950s). In ACC systems, the saturated steam from the steam turbine exhaust is carried directly to a very large array of A-framed fin-tube bundles, where large mechanical fans force air over the tubes, convectively condensing the steam.

ACC system

In Heller systems, the steam is condensed by spraying water directly into the exhaust flow in a ratio of about 50:1 (called "direct contact jet condensing"), creating a large volume of warm water, some of which is pumped back to the boiler as the working fluid and the rest of which is pumped to bundles of tubes arrayed at the base of a natural-draft hyperbolic cooling tower. The warm water circulating around the base of the tower and the cooler air at the top of the tower, combined with the tower's hyperbolic shape, stimulate a powerful updraft that draws ambient air over the tube bundles, thereby convectively cooling the water before it is returned to the condenser. Both are closed systems.

Heller system [Acronyms: "CW" = cooling water; "DC" = direct contact]

While the Heller system has been widely used elsewhere, there are none in the US. This is probably because the much lower auxiliary power requirements of Heller systems come with the visual impact of a large hyperbolic cooling tower (typically 150m high and 120m in base diameter), often a difficult sell given that most fossil power stations are located in the vicinity of the populated demand centers they're intended to serve. The auxiliary power required to run an ACC system is roughly twice the power required run a Heller system, and the Heller system is considerably quieter, but these have apparently been considered prices worth paying for the lower profile (a typical ACC system can be 40m high), particularly when it was cheap coal-fired power. Simple lack of familiarity could be another factor in the hidebound world of US power utilities.

The Electric Power Research Institute has kicked off a comparative study of indirect dry cooling (due to be completed in mid 2010), on the theory that it is the most economic dry cooling solution for large-scale thermal applications. The prospect of large amounts of CSP being built in the world's deserts calls for a reconsideration of the relative merits of these two approaches, since it would require dry cooling to be deployed in a different application and to a far larger extent than has ever been the case.

Three Bechtel engineers published a paper in 2005 (Digital Object Identifier reference DOI:10.1115/1.1839924) (originally presented at an American Society of Mechanical Engineers conference in 2002) that compared cooling technologies for combined-cycle gas power plants. They cited the following comparison of installed costs for various cooling systems, including ACC and Heller.

[Acronyms: "WSAC" – wet-surface air condenser]

They also note that the footprint of an ACC system is larger than that required for a Heller system, though specific data is not offered. Overall system efficiency of a Heller system is in the range of 2% better than an ACC system. That performance improvement meant one thing in a fossil power plant in the bad old days of cheap dirty power, but when it means 2% less land area covered by solar collectors, and lower auxiliary consumption of much more costly power, it takes on a much greater significance. The same sources note that since the Heller systems are mechanically far simpler than ACC systems, maintenance is much less of an issue and system availability is significantly greater. In the remote areas where these plants will be located, and given the large land areas over which they will spread, these are far more significant considerations than they were for compact fossil power plants located close to the populations they served. Another factor noted in these sources is that an ACC must be located next to the steam turbine it serves, because of the cost of transporting saturated steam over any distance, whereas the Heller system has much more flexibility in where the cooling tower is located. This will be much more important to CSP, where one can envision clusters of power tower complexes in a given area each with its own steam turbine, than it was with fossil plants. And finally, the feature that most worked against Heller systems in US fossil plant applications – visual impact – should be far less of an issue in remote desert sites, especially with solar power tower complexes where the central towers will likely be of similar height.

I should note that as a senior executive of the private power company InterGen in the late 1990s I oversaw the deployment of a Heller system on our 2,400 MW gas-fired combined cycle plant in Adapazari, Turkey (see below), which is still the world's largest installation of an indirect dry cooling system and continues to work extremely well. I trace my enthusiasm for the technology to that personal experience.

One final note on the term "Heller" system. A German engineering company, GEA, appears to own the trademark rights to the name "Heller", which they acquired when the bought EGI, the Hungarian company that commercialized indirect dry cooling systems. Indirect dry cooling is a generic technical solution that is often referred to as "the Heller system". I have no affiliation with GEA.

This piece originally appeared in Climate Progress.

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I am happy to see it pointed out that large amounts of water are not needed for solar power. Thanks.

There seem to be two design decisions here: whether to use direct or indirect condensation, and whether to use a cooling tower or forced cooling. Only 2 of the possible 4 combinations are discussed. Lets say I've decided I will use a cooling tower. What advantage is there to using the Heller system over placing a direct condensing system in my tower? (Other than less steam piping, I get that).

I see one advantage to direct: The steam is hotter than the water will be in the Heller system, so the fluid to air heat exchanger will be smaller, and hence cheaper.

Posted by: Bart Hibbs on May 1, 2009 8:52 AM

Gemasolar 17MW Power Tower with 16 hour heat storage

2009-05-02T03:29:00.000-07:00

Torresol Energy a collaboration of Sener, the Spanish Engineering Group, and the Masdar Initiative in Abu Dhabi is building Gemasolar a 17MW power tower solar thermal plant in Fuentes de Andalucia, just to the East of Seville, Spain

Gemasolar will be built so that it can run autonomously for 16 hours without any sunlight, effectively having an annual capacity factor 74% or 3 times that of a conventional power tower with no aftehours storage.

The system will directly heat a mixture of Potassium and Nitrate salts which then go through a heat exchanger to produce steam. This allows steam to be produced from the salt storage anytime day or night.

Gemasolar Solar Tres will consist of 2493 glass-metal heliostats (96m squared) with higher-reflectivity glass than what was used on a prototype in California named Solar Two that it is based on. Because of simplified design 45% reduction in manufacturing costs. It will consist of a thermal energy storage system, storing 6,250 T of molten nitrate salt (16 hours, 600 MWh). Add to this new advanced pump designs that will pump salt directly from the storage tanks, eliminating the need for pump sumps.

It will also consist of a steam generator system that will have a forced-recirculation steam drum. A more efficient, higher-pressure reheat turbine, and a simplified molten-salt flow loop that reduces by 50% compared to Solar Two California the number of valves.

Tower of power: Abengoa starts operation of second Spanish solar-thermal plant

2009-04-27T19:30:00.000-07:00

PV Tech - www.pv-tech.org

Abengoa Solar has begun commercial operation of its second solar power tower plant. Located near Seville, Spain, the 20-MW PS20 tower recently went through three days of production and testing, during which the facility surpassed the predicted power output.

The PS20 features a number of significant technological improvements compared to the 10-MW-capacity PS10, the first commercial concentrated solar thermal power tower, which is also located in the Solucar Solar Park. Abengoa says the enhancements include a higher-efficiency receiver, various improvements in the control and operational systems, and a better thermal energy storage system.

PS20 consists of a solar field made up of 1255 mirrored heliostats designed by Abengoa Solar. Each heliostat, with a surface area of 1291 square feet, reflects the solar radiation it receives onto the receiver, located on the top of a 531-foot-high tower, producing steam which is converted into electricity generation by a turbine.

The CSP plant, which was built by Abener, will produce enough electricity to power approximately 10,000 homes.

PS10 and PS20 are part of the Solucar platform project, which will eventually generate 300 MW of energy produced by a combination of trough, tower, and dish Stirling solar thermal concentrator installations as well as a modes deployment of photovoltaic modules.

http://www.pv-tech.org/lib/printable/5143/

Published: 28 April 2009

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Masdar City: A Source of Inspiration

2009-04-02T19:06:00.001-07:00

April 2, 2009

by Edward Milford

Abu Dhabi, UAE [Renewable Energy World Magazine]

Abu Dhabi's zero-carbon, zero-waste Masdar City is the focus of a much wider – and well funded – sustainable energy initiative from the heart of oil and gas world, as Edward Milford reports.

Money may not make the world go round, but the lack of it is most often what hampers a lot of renewable energy projects. In many respects, the multi-faceted Masdar initiative looks and sounds like a lot of other renewable energy master plans. However, it does have that key ingredient, money – and plenty of it. As a result, it is able to move forward rapidly and purposefully across a whole range of projects.

Abu Dhabi, part of the United Arab Emirates, sits on about 10% of the world's oil, and 5% of its natural gas. In just a couple of decades it has built up and profited from a large pool of energy expertise, centred round the oil and gas sector. The rulers of the Emirate are keen to maintain their global position in the energy business, and have recognized that in order to do this they will need to invest seriously in a range of new energy skills, particularly those around the renewable energy sector.

As a result, with the active support of the Crown Prince of Abu Dhabi, Sheikh Mohammad bin Zayed Al Nahyan, a decision was made to set up the Masdar initiative, and to support it with an investment of US$15 billion – making it currently the largest, single government, investment of its kind in the world.

The initiative is driven by the Abu Dhabi Future Energy Company (ADFEC), which in turn is a wholly owned company of the government of Abu Dhabi through the Mubadala Development Company.

The goal of the initiative is ambitious. It seeks to establish 'an entirely new economic sector in Abu Dhabi' one that will diversify the economy, be a knowledge-based industry and 'play a decisive role in Abu Dhabi's transition from a technology consumer to a technology producer.' More specifically, it will seek to position the country as 'a world-class research and development hub for future energy technologies' and 'drive the commercialization and adoption of ... technologies in sustainable energy, carbon management and water conservation.'

All of this could simply sound like unexceptional platitudes, just like many another renewable energy masterplan that gets on to, but not off, the drawing board. However, and crucially, the country not only has substantial expertise in global energy markets, it also has substantial resources. Using its cash, it is able to push forward rapidly, significantly and visibly in the areas it has identified.

Masdar City initiative

The initiative has several different strands. One of its most eye-catching elements is the construction of Masdar City, a zero-carbon, zero-waste development aiming to house 40,000 people with employment for an additional 50,000 commuters. Another aspect of the initiative is its utilities and asset management programme, which is both building a portfolio of operating assets and taking strategic equity stakes in companies around the world through the Masdar Clean Tech Fund.

Yet another strand is the development of the Masdar Institute of Science and Technology, being developed in co-operation with the Massachusetts Institute of Technology (MIT). The Masdar Institute will be sited in Masdar City, and another unit – the Industries Unit – is looking to invest in bringing renewable energy production to Masdar City.

A further component is Masdar's Carbon Management Unit to look both at carbon reduction and monetization, and also carbon capture and storage. The final piece, for now, is the World Future Energy Summit, together with the Zayed Future Energy Prize. It is an impressive and comprehensive list of activities, and many of them are also moving forward apace.

As the geographical core of the initiative, Masdar City has been one of the elements to move forward the most quickly. The concept is simple but radical; zero-carbon and zero-waste. This involves a radical rethink of everything about the way that the city will function, and has also led on to the adoption of the principles behind the WWF 'one-planet living' guidelines.

Sir Norman Foster, the British Architect, is behind the design of the city, and detailed planning and preparation has been done by a range of international consultants and experts, including Pooran Desai from BioRegional, the UK consultancy WSP and US-based CH2M Hill.

The seven square kilometre site chosen is near the airport and about 17 km from the city of Abu Dhabi, and, were it not in the desert, it would be classified as a 'greenfield' site. The fundamentals of the plan have been agreed, ground broken and phase one is underway. Over $300 million of procurement is in place, and an additional $1 billion is expected to be committed by the end of 2009. The city is due to be built in seven years, at a total cost of $22 billion. The first $4 billion of this is coming from the Masdar Initiative, with the remaining $18 billion being raised through direct investments and other financial instruments.

Much of the design will adopt local, vernacular architectural principles, but this will also be mixed with a lot of cutting-edge technology, some of it still in the experimental phase. The city will incorporate traditional medinas, souks and wind towers, and make use both of open, public squares and narrow shaded walkways to connect homes, schools, restaurants and shops. The buildings themselves will then adopt a wide range of passive measures, and should consume well under a quarter of the energy used by comparable buildings elsewhere in the region.

There will be no cars in Masdar City; indeed, no internal combustion engines of any type. Instead, there will be a network of electric trams (an LRT or light rail transit system, which will also link to the planned Abu Dhabi LRT system), and smaller, 'personal rapid transit' vehicles, effectively an automatic, driverless system of electric taxis controlled by a central computer. These will be programmed so that, once occupied, the passenger has privacy and no other passenger can board along the route.

All the energy used in Masdar will be renewably generated, not only the electrical power, but also that for heating, cooling and transport. The bulk of this is likely to come from solar of one form or another. There will be power generation for a smart grid from solar thermal power and concentrating PV, and also distributed PV throughout the city. The wind resource in Abu Dhabi is generally poor and will contribute little to the overall mix, but some geothermal and waste-to-energy, particularly from biowaste, are also likely to be significant contributors.

If you build it, will they come?

Masdar City expects to house a population of 90,000 people made up of 40,000 residents and 50,000 daily commuters. It has already announced its first major tenant; General Electric will site its new 4000 m² regional 'Ecomagination' centre in the city. This will support the development of energy-efficient products, and also showcase GE technologies in renewable energy, water treatment and other sectors. Importantly, it will also facilitate research and development work with the nearby Masdar Institute.

Other companies are likely to follow quickly. Abu Dhabi has offered to host the secretariat for IRENA – the newly-launched International Renewable Energy Agency – at Masdar. Many of the companies that the initiative will be investing in are also likely to site regional offices at Masdar. The financial benefits can be very significant: the city is designated as a 'Special Free Zone' and so there will be no restrictions on foreign ownership or capital movements, no taxes or import tariffs, and strengthened protection for intellectual property. A significant, global drive to attract industry partners to participate in the initiative is underway.

As well as providing a regional location, there are also numerous partnership opportunities for companies with technologies that may be used at Masdar. Among the energy technologies they expect to source are both PV and solar thermal power generation (concentrating PV, parabolic trough and parabolic dish generation); advanced thermal waste treatment plants; geothermal systems that can be used for district cooling; and smart grid management systems. They are also looking at a range of other district cooling systems, together with water desalination and grey-water treatment plants, and waste handling systems, including plasma and pyrolysis. More widely, procurement is also underway for IT systems, the transport infrastructure, and facilities management and services. A web-based portal is at: www.masdarprocurement.ae.

Investing in renewables

Masdar City is just one strand of the overall initiative. Another one that is already making its influence felt is the Industries Unit, which has been investing directly into a range of renewable energy companies. The flagship investment has been the creation of Masdar PV. This aims to become a top-three, global, thin-film PV company. They have recruited Dr Rainer Gegenwart as the CEO, and Joachim Nell as the COO. The company broke ground on a new factory near Erfurt in Germany in August 2008, and will shortly start building its Abu Dhabi plant using the same model. It expects to have final acceptance of its German plant by October 2009, and of its Abu Dhabi plant by March 2010. The Abu Dhabi plant will be the first high-tech semiconductor manufacturing facility in the region.

The initial target is to get the output up to 420 MW per year across the two sites (210 MW at each site) with an investment of $600 million. It has chosen thin film for its better performance at higher temperatures, and expects to sell mainly to integrators for systems of 100 kWp or larger. Its products will be modules that are 1.4, 2.8 or 5.7 m².

Masdar PV is also serving as the anchor client in the solar manufacturing cluster being established in Abu Dhabi. In the medium term, this aims to house crystalline, thin-film and concentrating PV manufacturing, as well as the supplier base to support these companies.

Several other renewable investments have been made, with major stakes taken in solar PV companies, such as Solyndra and Nanogram. Masdar is a significant investor with Abengoa in the Spanish solar thermal power company Torresol, which is just starting to build some new projects. In wind, Masdar purchased the Finnish company WinWind – and after Shell pulled out – Masdar took on a one-third stake in London Array – the large, offshore wind farm planned for the Thames Estuary in the UK.

Another strand to the Masdar initiative that should be visible very soon is the Institute of Science and Technology. This is being developed in Masdar City in co-operation with MIT. The Institute is launching its first Master of Science programmes in September 2009, and aims to have PhD programmes going by 2011. Recruitment of faculty staff has been carried out with MIT's assistance, and research will take place both in the US and in Abu Dhabi. Among the topics to be looked at will be hybrid solar energy conversion, high performance PV cells, wave power and integration of renewable energy into grids. Further details are at: www.masdar.ac.ae.

Other strands to the Masdar Initiative are Carbon Management, the World Future Energy Summit and the Zayed Future Energy Prize. The carbon management unit aims to monetize carbon reduction projects under the CDM, and support the development of carbon capture and storage.

The World Future Energy Summit has now been held twice in Abu Dhabi and is planned to be an annual event. It has attracted notable, high-profile speakers with former British Prime Minister Tony Blair giving the closing address at the 2009 event. A companion event, the European Future Energy Summit, is being launched in Bilbao, Spain, in June this year, see: http://www.europeanfutureenergyforum.com/home. The Zayed Future Energy Prize, associated with the Masdar Initiative and the World Future Energy Summit, was awarded this year to Dipal Barua, founding managing director of Grameen Shakti, who won $1.5 million, with Professor Martin Green of the University of New South Wales winning the runners-up prize.

The Arabic word 'Masdar' was chosen as the name of the project, as one definition of the word is 'source' – in the sense of the root or spring from which things originate. For years, many good renewable energy projects have suffered through lack of access to sources of funding. The Masdar initiative is showing that the combination of good projects and a plentiful source of funding can result in very rapid development of even the most ambitious plans. As such, it may also be a beacon for other places that are contemplating whether large-scale investment in renewables really can pay off.

Edward Milford is former publisher of Renewable Energy World magazine and is chairman of Earthscan, which publishes books and journals on renewable energy and other sustainability subjects. www.earthscan.co.uk

e-mail: edward.milford@earthscan.co.uk

http://www.renewableenergyworld.com/rea/news/article/2009/04/masdar-city-a-source-of-inspiration

Coming, solar thermal power unit

2009-04-02T19:05:00.000-07:00

CHENNAI: Tamil Nadu will soon have a solar thermal power station in Sivaganga district, chairman, Tamil Nadu Energy Development Authority (TEDA), Mohan Varghese Chungath told a meeting on 'Low Carbon and High Growth' organised by the State Planning Commission here on Wednesday. He said the Coimbatore based KG group had been showing an interest in the solar thermal unit. Permission was granted to them by the State Government to set up a 1 MW unit at Manamadurai in Sivaganga district, and the power plant was likely to come up in about 10 months, he added.The TEDA chief said Tamil Nadu had a good potential to harness solar power and the State was making all efforts to increase the renewable energy share. The future was with solar power and the state had been making remarkable strides recording the highest share of 32 per cent in renewable energy. Director, Centre for Climate Change and Adaptation Research, Anna University, A Ramachandran stressed the need for collaboration with developed countries like the UK to develop technology and devices to make significant progress in producing renewable energy. Though the potential to harness solar power was high, the cost was a prohibitive factor. Hence, photovoltaic cells that had a long life with cost effective technology was important. Deputy High Commissioner, British High Commission, Mike Connor, and Counsellor, Climate Change, British High Commission,Owen Jenkins, participated. Vice-chairman, State Planning Commission, M Naganathan told reporters that the meeting on low carbon was intended to offer a glimpse of the energy situation in the State to officials from the UK High Commission. " UK has been showing an interest in supporting a pilot project to help decarbonise the energy sector here and this is the first meeting,"he pointed out.

Action Plan for 50%: How Solar Thermal Can Supply Europe's Energy

2009-04-02T19:02:00.001-07:00

April 2, 2009 by David Appleyard, Associate Editor

In presenting a research agenda, the solar thermal sector sets out a strategy to reach a 50% contribution to Europe's space and water heating requirements by 2050. David Appleyard summarizes the document, which reveals what must be achieved if this ambitious goal is to become reality.

The research efforts and infrastructure needed to supply 50% of the energy for space and water heating and cooling across Europe using solar thermal energy has been set out under the aegis of the European Solar Thermal Technology Platform (ESTTP). Published in late December 2008, more than 100 experts developed the Strategic Research Agenda (SRA), which includes a deployment roadmap showing the non-technological framework conditions that will enable this ambitious goal to be reached by 2050.

A strategy for achieving a vision of widespread low-temperature solar thermal installations was first explored by ESTTP in 2006, but since then the SRA has identified key areas for rapid growth. These focus points include

the development of active solar buildings, active solar renovation, solar heat for industrial processes and solar heat for district heating and cooling. Meanwhile, amongst the main research challenges is the development of compact long-term efficient heat storage technology. Once available, they would make it possible to store heat from the summer for use in winter in a cost-effective way.

The ESTTP's main objective is to create the right conditions in order to fully exploit solar thermal's potential for heating and cooling in Europe and worldwide.

As a first step for the development of the deployment roadmap and of the Strategic Research Agenda, ESTTP developed a vision for solar thermal in 2030. Its key elements are to establish the Active Solar Building – covering 100% of their heating and cooling demand with solar energy – as a standard for new buildings by 2030; establish the Active Solar Renovation as a standard for the refurbishment of existing buildings by 2030 (Active Solar renovated buildings cover at least 50% of their heating and cooling demand with solar thermal energy); supply a substantial share of the industrial process heat demand up to 250°C, including heating and cooling, desalination and water treatment; and achieve broad use of solar energy in district heating and cooling.

'The benefits of increased solar thermal energy usage are immense', explained ESTTP chairman Gerhard Stryi-Hipp, adding: 'Supporting R&D into the next generation of solar thermal applications must have a high priority for governments everywhere in Europe, because solar thermal is a key to reaching Europe's goal of 20% renewable energy by 2020.'

Market drivers

Heating accounts for a significant proportion of the world's total energy demand with the building sector alone consuming 35.3%, of which 75% is for space heating and domestic water heating (IEA, 2006). In Europe, the final energy demand for heating and cooling at 49% is higher than for both electricity at 20%, or transport at 31%.

Despite these figures, for a long time low-temperature solar thermal only played a minor role compared to other renewable energy sources. It was mainly considered suitable for water heating needs and consequently, in future energy strategy scenarios, renewable heat generation frequently played only a small role.

However, the situation has changed dramatically. Without doubt, the European goal of covering 20% of energy needs with renewable energy can only be reached with a significant increase in the renewable heating sector. Within this sector, it is low-temperature solar thermal technology that has the greatest potential.

The large technological development potential of low-temperature solar thermal has been triggered not only with enhancements to system types and components, but primarily in the development of new uses for the technology, such as solar heating, process-heating generation, district heating and solar assisted cooling. Volatility in crude oil and natural gas prices, along with increasing import dependency, have further increased public attention and interest.

It is expected that the energy and climate crisis will drastically change the heating market over the next two decades. In new buildings, a tightening of energy performance requirements, including obligatory use of renewables, will be increasingly required. In the existing building stock, energy savings will become the key driver for renovations, and district heat operators will become more interested in, and possibly be forced to, increase the share of renewables.

For industrial process heat and cooling, the key driver will be the need to reduce growing energy costs, and possibly the cost of emission allowances at the carbon market.

All these developments will lead to a sharp increase in the use of solar thermal, and the subsequent need for new technologies.

Active solar buildings

The ESTTP vision is to establish the Active Solar Building as a standard for new buildings by 2030. For existing buildings, the aim of the ESTTP is to foster Solar Active Renovation. The aim is also to cover substantially more than 50% of the remaining heating and/or cooling demands with active solar energy.

There are already many Active Solar Buildings with a proven track record in Central Europe. The first one-family house covering 100% of its heating requirements with solar energy was created in Switzerland back in 1989. More recently, the first multi-family buildings with 100% solar thermal coverage were introduced.

Cost-effective and practical solutions to heat storage represent a key technological challenge, since the widespread deployment of Active Solar Buildings largely depends upon it. The ESTTP vision assumes that, by 2030, heat storage systems will be available with an energy density eight times higher than water.

For solar collectors, significant improvements are still possible, particularly in terms of cost reductions and design. However, low temperature collectors, which are usually used on buildings, are already very efficient.

High energy efficiency values can be reached through high insulation standards, which reduce losses, and optimal architecture which integrates passive solar measures, such as active windows, shading or ventilation systems.

Furthermore, the productivity of solar thermal systems is enhanced by heating and cooling systems that require a low temperature difference between the supply system and the indoor temperature, such as radiant surfaces, floor heating and cooling, ceiling heating and cooling, and heating/cooling of ventilation air. Most of these solutions already exist, but there is still the potential for cost reductions, increased performance and easier integration.

The demand for cooling in buildings is growing dramatically; and not only in Southern Europe. Despite the impressive growth rates, solar-assisted cooling is still in the very early stages of development. Over the next decade, the first systems supplying domestic hot water, space heating and cooling for buildings will be installed.

However, significant R&D must be carried out in order to exploit the potential for further technological development, which will pave the way for the large-scale deployment of solar cooling.

In the future, solar active systems, such as thermal collectors, PV-panels and solar hybrid systems, will be obvious components of roofing and facades and they will be integrated into the construction process at the earliest stages of planning. Walls may also function as a component, supporting thermal energy storage through the application of, for example, phase change materials. One central control system will lead to an optimal regulation of the whole heating, ventilation and air conditioning (HVAC) system, maximizing the use of solar energy. Heat and cold storage systems will play an increasingly important role in maximising solar thermal contributions.

While a very small number of Solar Active Buildings have already been showcased, making this a mainstream building standard by 2030 will only be possible if significant technological progress is achieved in high-efficiency solar collectors that will increase the energy gained under winter conditions, while maintaining high levels of durability and increasing the cost efficiency of the manufacturing and installation process.

Other key developments include compact, time indifferent thermal storage technologies that significantly reduce the space required for heat storage devices. This will lead to cheaper and more practical seasonal heat storage. Improved solar thermally driven cooling systems will make it possible to cover much of the rising demand for air conditioning with solar energy, while intelligent control systems of the overall energy flows in buildings will contribute to a reduction in energy consumption and the optimization of solar energy usage.

Industrial heating and cooling

Solar Heating for Industrial Processes (SHIP) is currently at the very early stages of development. Less than 100 operating solar thermal systems for process heat are reported worldwide, with a total capacity of about 24 MWth. Most of these systems are of an experimental nature, and are relatively small-scale. However, there is great potential for market and technological developments, as 28% of the overall energy demand in the EU27 countries originates in the industrial sector, and much of this is for heat of below 250°C.

In the short term, SHIP will mainly be used for low temperature processes, ranging from 20°C to 100°C. With technological development, more and more medium temperature applications, of up to 250°C, will become market feasible. Around 30% of the total industrial heat demand is required at temperatures below 100°C, which could theoretically be met with SHIP using current technologies, and 57% of this demand is required at temperatures below 400°C, which could largely be supplied by solar in the foreseeable future. In several specific industry sectors, such as food, wine and beverages, transport equipment, machinery, textiles, pulp and paper, the share of heat demand at low and medium temperatures (below 250°C) is around 60%. Tapping into this potential would provide a significant solar contribution to industrial energy requirements.

Substantial potential for solar thermal systems exists in the food and beverages, textile and chemical industries, as well as in washing processes. Among the industrial processes, desalination and water treatment (such as sterilization) are particularly promising applications for the use of solar thermal energy, as these processes require large amounts of medium-temperature heat, and are often necessary in areas with high solar radiation and conventional energy costs.

Clearly, the use of solar heating for industrial processes should be part of a comprehensive approach, which also takes into account: energy efficiency measures; the integration of waste heat into processes; and a reduction in heating and cooling demand through the use of a heat exchange network.

An ample choice of solar thermal collectors is commercially available for low temperatures (operating temperatures up to around 80°C–90°C) and for high temperatures (>250°C, mainly used for electricity generation). The development of cost-effective and reliable medium-temperature collectors, which can meet the requirements of most industrial processes, is now required.

Other components of solar systems also need to be adapted to this range of temperatures. For example, development of the industrial solar market would benefit from the development of a new generation of compact and/or seasonal heat storage systems, and from advanced controllers.

Furthermore, despite the fact that many processes in the industry operate at temperatures below 100°C, the heat supply of most industrial machines is currently provided by steam networks operating at between 140°C and 180°C. This makes the use of solar thermal less attractive, or even impossible. Switching to lower temperatures would imply significant investment on infrastructure and network modification and process redesign, which reduces the attractiveness of solar energy. Nonetheless, new technologies can be developed, which allow processes to operate at lower temperature. One example is the reduction of bath temperatures in pickling plants. In some cases, processes can also be efficiently redesigned to make them more compatible with the daily and/or seasonal cycle of solar energy supply. Moreover, when new, long-term industrial process facilities are planned, there is always the possibility of subsequent solar add-ons.

Integrating solar thermal into industrial processes will be a complex process, requiring support from energy agencies and other public players, dedicated to specific industrial sectors. Research is necessary in a number of fields, including stagnation behaviour and management of large collector fields; monitoring; and system optimization methodologies.

Another requirement is the need for dedicated design guidelines and tools. Currently only a few engineering offices and research institutes have experience with SHIP installations. Planning guidelines and tools for typical industrial uses need to be made available to a wider community of experienced engineers. This would mean that other potential users could be offered a solar solution, system design costs would fall, and the broader experience would increase the effectiveness of such installations.

However, solar systems are capital intensive, as costs are mainly up front, and industrial companies often optimize their processes with short-term return on investment expectations that cannot currently be met by solar systems. The wide market development of industrial and process solar would also require dedicated financing and contracting solutions, the lack of which is currently an important barrier to growth. It is crucial, therefore, to rapidly create a market, in order to reach the minimal critical mass required to start benefiting from economies of scale. While R&D can increase potential and reduce costs in the medium term, financial incentives and widespread public-funded demonstration projects are an absolute necessity.

District heating and cooling

Currently, around 9% of the total heating needs in Europe are covered by block and district heating systems. This share is much higher in a number of countries, especially Eastern Europe and Scandinavia.

Within district heating systems, solar thermal energy can be produced on a large scale and with particularly low specific costs, even at high latitudes, such as in Sweden and Denmark. However, only a very minor share (less than 1%) of the solar thermal market in Europe is linked to district heating systems, which together account for less than 0.5% of EU installed solar thermal capacity. However, their combined capacity is still higher than that of 25,000 small solar domestic hot water systems.

The prevalence of Scandinavian countries is surprising, since solar radiation is lower in this region. Central and Eastern European countries and district heating systems in Southern Europe offer much better conditions.

Typical operating temperatures range from low (30°C) to high (around 100°C) for water storage. The majority of plants are designed to cover the heat load over the summer months (hot water and heat distribution losses) using diurnal water storages. However, some are equipped with seasonal storages and cover a larger part of the load. The seasonal storages comprise water in insulated tanks, the ground itself, aquifers and a combination of ground and water. More than 80% of Europe's existing plants are equipped with flat-plate collectors, mostly large module collector designs. Most plants also have pressurized collector systems with an anti-freeze mixture – usually glycol and water – while a few plants in the Netherlands have drain-back collector systems.

Several solar district heating systems, especially in Sweden and Denmark, have ground-mounted collector arrays. This can be a very cheap solution, when surfaces are available and solar is connected to a network serving existing buildings.

In the short-term, the broader use of solar energy within district heating (and cooling) systems is mainly a question of policy – namely, incentives, regulation, and the demonstration of existing technologies. In the medium- and long-term, considerable R&D efforts are needed to utilize the full potential of large-scale solar systems linked to district heating. The need for basic and applied research is mainly related to the development of durable and cost-effective (plastic) liners and water resistant insulation materials for long-term (seasonal) storage. Basic and applied research is also required to further develop large-scale solar collectors, as well as dedicated control devices and optimization strategies.

Widespread deployment of solar thermal

Compared to other continents, Europe has the most sophisticated market for different solar thermal applications, with a relatively wide mix of different applications such as hot water preparation, space heating of single- and multi-family homes and hotels, large-scale plants for district heating as well as a several pilot systems for air conditioning, cooling and industrial applications. However, also in Europe, the majority of the new solar thermal systems are installed on residential homes for heating domestic hot water only, with solar typically providing 40%–80% of demand. Nevertheless, there is already a clear tendency towards combined systems for hot water and space heating in countries like Germany and Austria, where 50% or more of the newly installed systems are combined systems.

Additionally, in markets like Spain, France and Austria, large systems for multi-family homes have a significant share. The systematic development of the market for collective systems is important to reach the short to medium-term goals, since the majority of the European population lives in such dwellings.

Of course, deployment must go hand-in-hand with substantial improvements in the energy efficiency of buildings and of heat consuming processes. It is imperative that both pathways develop as rapidly as possible to dramatically increase efficiency and to replace the remaining heating and cooling demand with renewables.

Higher efficiency values create the necessary conditions for a fully renewable supply of thermal energy demand, freeing scarce fossil fuel resources for other purposes where they are less easily replaceable.

While oil and gas prices may have dropped in the current downturn, using fossil fuels or electricity for heating and cooling buildings is likely become too expensive for most people in the longer term and will be seen as an unacceptable squandering of resources.

By overcoming a series of technological barriers, it will be possible to achieve a broad-scale market introduction of advanced solar thermal applications at competitive costs.

ESTTP predicts that with political support mechanisms and technical developments based on increased R&D, realistic growth rates of 20% in the solar thermal market are achievable. These growth rates would lead to an installed capacity of 970 GWth by 2030 in the EU, supplying about 8% of the total heating demand.

Combined energy conservation measures and increased efficiency in buildings that could slice some 40% of total heat demand would enable solar thermal systems to supply about 20% of the overall heat demand in the EU-27 by 2030.

The long-term potential of solar thermal is to provide about 50% of EU heat demand by 2050, an installed capacity of 2576 GWth or 8 m² per inhabitant.

The strategy concludes that low-temperature solar thermal must play an important role in the research programmes of the EU and its member states. The funding for solar thermal research must be significantly increased and the research capacities must be systematically expanded.

'Solar thermal can provide much more than just domestic hot water', says ESTTP chairman Gerhard Stryi-Hipp, adding: 'Already today solar thermal systems combining hot water preparation and support to space heating are in wide-spread use in Central and Northern Europe. But to reach our goal of 50% of heating to be supplied by solar thermal energy, new applications have to be developed and deployed.'

David Appleyard is associate editor of Renewable Energy World.
e-mail: rew@pennwell.com

http://www.renewableenergyworld.com/rea/news/article/2009/04/action-plan-for-50-how-solar-thermal-can-supply-europes-energy

Eleven Cool Names and Concepts to Watch in Air Conditioning

2009-03-31T17:33:00.001-07:00

by: Michael Kanellos

March 31, 2009

Ice Energy's Ice Bear air conditioner cooling system creates ice at night when power is cheap.

Ice Energy

Air conditioning management.

In most circumstances, it's not the kind of job that attracts groupies. Nonetheless, the subject will begin to occupy a greater portion of the energy debate as energy efficiency and green buildings expand. Building operations consume 39 percent of the energy in the U.S. and HVAC gobbles up a big part of that. Air con and ventilation account for 15 percent of the energy used in commercial buildings, while heating accounts for 36 percent. Air conditioning represents about 16 percent of the electricity consumed in homes. The percentage of homes with air conditioning rose from 27 percent in 1980 to 55 percent in 2001.

Worse, the air conditioners come on during the hottest days in the year en masse, when power is at its peak price and brown-danger looms. Secretary of Energy Steve Chu, in his previous assignment at Lawrence Berkeley Labs, oversaw one of the premier research centers for building management.

Although companies such as Johnson Controls and Honeywell have continually improved the efficiency of their products, the design and operation of buildings, the aged install base and other factors leave a lot of room for improvement.

The following is a guide to startups and others trying to crank down the high cost of cooling.

1. AC Research: Formerly known as Viridis Earth, AC Research has effectively devised a computer-controlled misting system for residential air conditioners. The product essentially sprays water vapor into the air around an air conditioner, the same way misters at outdoor cafes keep patrons cool. The goal of the system is to keep the air around the air conditioner around 80 degrees, which in turns leaves less for the air conditioner to chill. The trick is getting the sensors and control systems to work together, says founder Tuyen Vo. Vo came up with the idea after the 2001 blackout. He learned about cooling when working with cryogenic pumps at a semiconductor maker.

Pre-cooling can save a home in a hot region around $500. AC will conduct trials with two utilities later this year.

2. Octus Energy: The company is trying to commercialize a technology out of UC Davis called WicKool that collects the condensate (i.e., water drops) extracted from the cool air flows created by an air conditioner and uses that to pre-cool incoming air. Octus Energy's design also lets building managers get rid of a condensation ejection system. It's a passive system but can improve air conditioner efficiency by 3 percent to 5 percent. It's been tested at a Walmart and Target in the Sacramento, Calif. area. WicKool may license to other companies.

3. Smart Cool Systems: Smart Cool Systems has algorithms that optimize the compressor in commercial or residential air conditioners, the component that can account for up to 70 percent of the power consumed by some systems. More than 26,000 of its energy saving modules have been installed. Smart Cool Systems has been around for nearly 20 years and is still small.

4. Chromasun: Chromasun has developed a solar air conditioner from Ausra co-founder Peter Le Lievre (see Ausra Co-Founder Returns With Solar Air Conditioner). Solar air conditioner? Heat is captured with a rooftop device similar to a solar thermal power plant. The heat is then used, instead of natural gas, to boil a refrigerant in a solution in a sealed chamber. Through heat exchangers and manipulating the pressure inside the sealed chambers, the refrigerant is re-condensed into a low-temperature liquid and employed create cold air. The evaporation-condensation cycle goes as long as the sun provides enough heat.

Fifty percent of the demand for power during peak periods in California and 70 percent of the power in Dubai can be attributed to air conditioners, according to Le Lievre. Peak power typically comes when air conditioners are cranking their hardest.

"Ninety-five percent of that can be tackled by a solar thermal air conditioner on the roof," he said. "The biggest market is for peak AC."

5. Ice Energy: This one is best understood without technical talk. Ice Energy's Ice Bear makes ice at night, when power is cheap. The stored energy (i.e., chilly vapor) then runs the air conditioner at night. Remember sticking your head in the fridge on sunny days and breathing? Similar principle. The company says its systems collectively have performed for two million hours in the field and that it is currently bidding on twenty utility projects.

6. GroundSource Geothermal: Sandblasting with steel. GroundSource Geothermal has devised a way to drill holes for geothermal cooling systems with steel sand, rather than a drill bit. The drilling unit, which relies in part by ideas from some of the same people who brought you the hot rock geothermal technology at Los Alamos National Labs, can also take advance acoustic readings of soil to improve drilling efficiency. The technology is also being improved so you can drill through the foundation of your house. it can also be used for heating and cooling.

While Lord Kelvin first studied ground temperatures, Robert Webber invented the first shallow geo heat pumps. Throughout most of the U.S., the temperature of the ground about five feet below the surface remains roughly constant throughout the year: 45 degrees to 50 degrees Fahrenheit in the northern parts of the country and 50 degrees to 70 degrees in the south.

7. PhotoSolar, Sage Electrochromics: Technically, PhotoSolar and Sage Electrochromics are not air conditioner companies, but they keep heat from entering buildings, which reduces the strain on the air conditioner. Denmark's PhotoSolar has a film that keeps out 50 percent of solar radiation. Sage has windows that dynamically change tint with daylight: after several years of development Sage is moving toward a wider commercial release.

In this same vein, more things you can add to the list are LED and energy efficient lighting companies like Bridgelux (less waste heat – less air conditioner work), contractors selling white roofs (heat reflectors), data center efficiency experts, and industrial waste heat specialists like Recycled Energy Development.

8. Maglev compressors: This isn't a company name, we're just listing the concept. The same technology that allows high-speed trains to float in Japan is now being used to run compressors. "They are really incredible compressors," said David Leathers, a VP at Limbach, one of the country's larger engineering contractual firms. (Limbach has done work for the both the Detroit Lions and the NRDC, which will not be playing each other in the playoffs.)

9. Optimum Energy: The company thinks in tons. It has created software that dynamically adjusts the activity of water chillers in large buildings. Optimum Energy says it can cut the energy required for a ton of water in a large building's chiller system down to 0.5 kilowatts (see Better Cold Water Through Software). Older buildings can consume 1.4 kilowatts. Even LEED platinum buildings can consume 0.7 kilowatts, said founder Nathan Rothman, CEO. The software adjusts the activity of the chiller by looking at occupancy data, temperature, etc.

10. Cimetrics: Instead of controlling the water, Cimetrics controls what goes on inside your building. It monitors thermostats, carbon monoxide sensors and other systems. It then matches the performance of the HVAC system against a simulation that determines how it should be performing.

"It is like data mining for buildings," says CEO James Lee, who says the way Americans heat and cool buildings is "absolutely ridiculous."

11. Comverge, EnerNoc and other demand response companies: Although you've heard about the smart home, those smart meters and other wireless devices right now are primarily connected to the heating and air conditioning system.

And bonus number zero. Nothing. This is perhaps the ultimate system for reducing air con power. In some areas such as Seattle and Northern California, architects like Perkins + Will are just leaving out the air conditioners. It cuts power and gives developers a nice bonus of LEED points. This can be supplemented with air side economizers that draw in scrubbed ambient air. (These devices can also be used to cool data centers in cold climates like Ireland.)

An Interview With eSolar's Bill Gross

2009-03-31T17:28:00.000-07:00

By Chris Morrison | March 31st, 2009 @ 4:40 am

Bill Gross might just be the quintessential inventor / entrepreneur. Born in the late 1950s, Gross began inventing gadgets in high school, and had founded a company by college. After graduating he started making software; among his various innovations, Gross could be called responsible for the advertising concept that has made Google so rich. In 1996, he founded Idealab, an incubator for new tech startups.

Today, Idealab houses or has investments in electric car company Aptera, concentrating solar system designer Energy Innovations, Infinia (which I just covered in Fortune Small Business), and other cleantech companies. Then there's eSolar, which Gross heads up personally. With money from Google.org and Oak Investment Partners, the company is one of only a small handful of solar startups that may be close to competing with fossil fuels on price.

The technology that eSolar uses is a form of solar thermal, in which many mirrors focus sunlight on water enclosed in a pipe or chamber, which then turns to steam, driving a turbine. For eSolar, that means 16 fields of 12,000 mirrors each focusing on "power towers", which send their steam to a central turbine, producing 46 megawatts of power. The first eSolar plant will produce steam next month and electricity in May; if all goes according to plan, partners will then begin building full-scale solar thermal plants.

BNET: What led to founding eSolar?
Gross: I was in high school during the energy crisis of 1978, reading Popular Science, loving trigonometry. So I decided to build a parabola. I took metal shop and worked on ways to make it cheaper. I decided to advertise my plans, and sold them for $4 after copying them for $1. Over the next 3 years, I sold 10,000 copies, and they paid my way through CalTech – actually, they probably got me accepted to CalTech.

Then when I graduated, the energy crisis was over. And an IBM PC had come out, so I bought one and started writing software. After 2000, I dusted off my parabola plans and saw what had happened over 20 years. I was surprised — it wasn't much at all.

BNET: You've quoted prices for electricity from eSolar plants that are lower than what competitors claim. So how do you make solar cheaper?
Gross: Mirrors are two thirds of the cost. In the early days, people built fields with 10 square meter mirrors and said hey,it's too expensive. So how do we make it cheaper? Let's make it bigger! They went to 20, 50 meters. In Spain they're over 100 square meters. And every single parabola needs to be hand-tuned.My conclusion was, you need to go smaller, not bigger. When that happens you have less up in the wind. For the same reason wind mills go high, you want to stay low.

The only problem when you get smaller is software control. We can't afford to have a human survey 24,000 locations. You couldn't have done this product 10 years ago. Even 5 years ago, what we're paying $5 for a microprocessor would have been $1,000. Our breakthrough has been to use flat mirrors and software to direct them. Now the field costs just a third of the total.

BNET: What are you projecting your costs to be?
Gross: We can build and install these plants for between $2.50 and $3 per watt. The levelized cost of energy will then depend on the sunshine. That will also vary. The combination of cost per watt to build and sunshine will yield levelized energy costs in the range of 10 cents. In some areas we can compete with natural gas with no subsidies, today. The areas that make sense are the southwest United States, western India, Australia, Mediterranean Europe / Northern Africa and the Middle East are ok. Outside of that you'll want thin-film or solar PV.

BNET: Are you concerned about competition?
Gross: The market is so large, we almost don't view anyone as competitors. It's in the hundreds of gigawatts, if not terawatts, if we can get the price right.

All of us are going at a way of getting the cost of construction and deployment low enough to compete without a subsidy. The other companies are all taking slightly different approaches. And I think solar thermal in general is the cheapest way of doing solar. It means people can get electricity with less of a rate increase. I sort of want us all to succeed, because that will convince governments that we deserve investment.

BNET: Companies hoping to build big solar thermal plants in the desert are running into political and environmental roadblocks. Is that a problem for eSolar?
Gross: Of the $130 million we raised, we spent $30 million on land. We went and bought, specifically, previously disturbed farmland near transmission. So we don't have to worry about wildlife migration patterns. We bought private land, so we don't need special permission. Our 46 megawatt plant takes up a quarter square mile, much smaller than other power tower plants. And one other benefit of going smaller is that the towers are smaller; that's important for neighbors. If you're above 180 feet, the FAA comes into play and neighbors may complain. We stayed lower than 180, around the height transmission towers are anyway. So we can locate much closer to the city.

But [society] still can't decide that we want clean energy, but not make some other sacrifice to get it. We're building power plants with zero emissions or ill effects on the environment. Even if you don't believe in global warming, there are still bad things about coal plants. I think we need some relavitism. We should make the least impact possible, and not ruin pristine wildlife. But people have ruined pristine wildlife with coal plants that kill 10,000 people in the neighborhood yearly. I think coal plants have better lobbyists.

BNET: Financing troubles have hurt other renewables. Will solar thermal be able to buck the trend and keep growing through the recession?
Gross: About a year ago, you could build a solar plant and get money at 5-7 percent interest. As financing rates have gone up to the 12-14 percent range, every point of interest rate cuts about 5 points of gross margin for the company doing the install. If it was 6 and now it's 11, that ate your 20 percent margin. That's why for PV it's not happening. We're very lucky because of the cost of our technology. We're economic even at 12-15 percent interest. We make less profit, but at least we're still profitable. As interest rates come down, it will get better.

But not only are the interest rates high, some banks still aren't lending. They're too scared. Outside of solar, we have this building in Pasadena that eSolar is in. What if you borrowed against the building – just half? Wells Fargo won't even loan for that. The climate is so bad for borrowing money on projects, everyone is looking for loan guarantees from the Fed.

But you don't want to rely on the government. You need private capital. Unfortunately, the banks aren't acting like banks, they're acting mattresses.

Power-up for clean technology

2009-03-31T17:25:00.001-07:00

John Dyson
April 1, 2009 - 12:09AM

AMID the gathering clouds of the global economic storm, clean technology innovation can offer Australia a ray of hope.

Clean technology is more than energy solutions for a polluted planet. It is promoting innovation in all industry sectors, from water preservation and quality to housing, food supply and security.

Australia was behind the first wave of clean energy innovations now powering the world. Twenty years ago, solar photovoltaic cell technology left for Spain. Shortly after, evacuated tube technology went to China. Then evacuated glazing technology went to Japan.

In 2001, Dr Shi and his solar cells developed at the University of NSW went to China — and his company Suntech is now the world's biggest producer of solar panels. In 2002, crystalline glass technology went to Germany. In 2007, the solar thermal compact linear Fresnel reflector from the University of NSW went to the US.

If we can develop the next wave of clean technology industries, we will be rewarded with hundreds of thousands of green infrastructure and manufacturing jobs, export industries, and investment and re-investment in Australian science and entrepreneurs.

Australia has abundant resources when it comes to wind, solar, tidal and geothermal power generation. Despite past losses, we have a new crop of clean technology companies poised to become world leaders, capable of growing into huge export-earners and job-creators.

We are world class in developing solar thermal technology, concentrating photovoltaic systems, developing thin-wafer solar cells and harnessing wave and tidal energy, with companies such as Ausra, Solar Systems, Oceanlinx, BioPower and CETO garnering attention overseas, and geothermal companies such as Geodynamics, Petratherm, Green Rock and Panax leading the field. We need to invest in these industries to enable them to become competitors with wind technology — an important industry, with imported technology and equipment. As yet, however, most of the benefits are flowing to other countries.

But to create these new industries, we need the right national investment structure to nurture our scientific research, support on-shore commercialisation and establish standards.

Globally, clean technologies have attracted serious investment. New Energy Finance found new investment in energy technologies expanded by 4.7 per cent, from $US148.4 billion ($A216.5 billion) in 2007, to $US155.4 billion in 2008. This includes venture capital, project finance, public markets and research and development expenditure. And some clean technology investments have already justified their early investment. Global revenues from the solar photovoltaics, wind power and biofuels sectors increased 53 per cent in 2008 — and are predicted to reach US$325 billion in the next decade, the latest Clean Energy Trends report shows.

Yesterday Australia's clean technology investment leaders met in Melbourne to review the return on investment potential and how governments and the private sector could support the growth of this national asset. Starfish Ventures, among other venture-capital firms, is investing in clean technology and searching for companies with the technology and leadership to ensure Australia develops the next crop of leaders.

In recent weeks, the Federal Government has committed itself

to an $83 million Innovation Investment Follow-on Fund to help more than 20 venture-capital fund managers licensed by the Commonwealth under existing programs. This is a welcome move and a step in the right direction.

Federal and state governments are also playing a key role in creating the right regulatory structure to attract investment for local and international firms. This so far includes the proposed emissions trading scheme and renewable energy target.

While it is important to get these policies right, the investment community urgently needs regulatory clarity so investors can plan funds allocations and nurture current investments for the years ahead.

In the latter part of the last century, Australia developed strong manufacturing, construction and natural resources sectors. It is now time to seriously commit to a clean technology innovation and commercialisation program — and keep backing these companies until they grow into national brands.

By supporting research, innovation and entrepreneurship, Australians stand to reap the much-needed financial and intellectual benefits for decades to come.

John Dyson is investment principal at Starfish Ventures.

This story was found at: http://business.theage.com.au/business/powerup-for-clean-technology-20090331-9idf.html

The producers of photovoltaic modules with thin layers lower their production costs and become more competitive

2009-03-29T06:36:00.001-07:00

THIS POST WAS WRITTEN BY ON MARCH 29, 2009

POSTED UNDER: ENERGY

The production of electricity from photovoltaic (PV) could compete with conventional power plants earlier than expected: for the first time, the production costs of the American company First Solar, which produces thin-film cells in telluride Cadmium (CdTe), have fallen below a dollar per watt ($ 0.98 / W). The success of the U.S. serves as a landmark reference in terms of competitiveness by PV solar electricity. Until now, PV technologyis not competitive vis-à-vis conventional energy sources, because its production was too expensive, particularly because of the cost of silicon (Si), a material that generates electricity in the current PV cells. Experts were expecting the "parity network" in Germany for 2015 at the earliest. Thanks to recent progress, this parity network seems to be in time, according to Holger Krawinkel, energy expert at the Federation of Central consumers . According to him, "the First Solar modules could already produce electricity for an equivalent of 0.20 to 0.25 euros per kilowatt hour." But the current price of electricity in Germany currently around 0.20 euros / kWh.According to the company's CEO, Mike Ahern, First Solar has reduced production costs due to a rapid increase in production and a better product and process. "Our production has increased by 5000% between 2005 and today to reach 1000 MW. At the same time, the demand for materials has decreased and the performance of the modules has increased. First Solar is one of the few producers of thin film cells on an industrial scale. The company replaced the Si layer by a hundred times smaller made of a semiconductor CdTe. It captures many photons, such as Si, but its production is less expensive while technology crystalline silicon blocks are first sliced, then worked in several stages to provide solar cells, First Solar files directly to the semiconductor from a few micrometers thick on the glass. A disadvantage of thin film modules is their relatively low yield (11%) are less efficient than crystalline silicon modules, which convert about 15% of light into electricity. In addition, CdTe PV cells need a surface larger than the crystalline Si cells to produce the same amount of electricity. High prices offset installation and negative, in part the low cost of production. However, along with First Solar, increasing competition and other companies engaged in the production of PV modules with thin layers: - The U.S. AVA Solar has invested $ 150 million in a new facility, which should begin in April 2009 the production of CdTe modules. AVA Solar will soon be in production costs below $ 1 / W. - Berlin Inventux The company pursues the same objective. It happened since late 2008 modules if said "micromorphe. The technique is a further development panels to thin film cells marketable, made from simple amorphous Si. With the help of an additional absorber microcrystalline Si deposited on the amorphous layer, the producer has improved the electrical efficiency of more than 8%. The savings will be, above all, due to economies of scale associated with increased production. The company doubled the capacity of its facility in Berlin from 33 MW in the next 2 years. - The U.S. company Nanosolar has developed a production process that prints on a film of tiny nanoparticles of copper, indium, gallium and selenium (CIGS) and possibly sulfur. The producers want to reduce costs only 0.30 to 0.35 dollars with their innovative method of printing. The plants are ready to start series production. In a 430 MW plant in San Jose, California, Nanosolar producing cells to be transformed into modules Luckenwalde near Berlin. Despite growing competition, First Solar is confident in its position as market leader. "With expansion coming, we want to reduce costs 0.65 to $ 0.70 / W by 2012," said the businessman Ahern. According to experts, the techniques for thin film PV will win many shares in the coming years thanks to their high potential for development. However, the effectiveness and costs of silicon solar cells are still capable of improvement.

China experiments with solar-thermal power

2009-03-26T20:55:00.001-07:00

Mar 26, 2009

Power from the sun in China

Construction is due to start later this month on an experimental solar–thermal power plant in the shadow of China's Great Wall that will bring clean energy to 30,000 households by 2010. Built on the outskirts of Beijing at a cost of £10m, the 1.5 MW Dahan plant will cover an area the size of 10 football pitches, and will serve as a platform for experiments on different solar-power technologies.

Unlike photovoltaic solar panels, which produce electricity directly from sunlight, solar–thermal power is based on an array of mirrors that focus the Sun's rays onto a receiver. Several solar-thermal plants are already operating elsewhere in the world — notably in California's Mojave Desert and in Granada in Spain — but the Dahan facility will be the first of its kind in Asia.

"The actual amount of power generated is small, but it is a big step for China to go into solar-thermal power generation using its own designs," says Christoph Richter, site manager of the German Aerospace Centre at the Plataforma Solar de Alméria, a solar-power research centre in Tabernas, Spain.

100 'heliostat' mirrors

The Chinese design relies on 100 curved "heliostat" mirrors that track the Sun's movement across the sky and redirect light onto a receiver atop a 100m–high central tower. Water flowing through the receiver is transformed into superheated steam, which can then drive electricitygenerating turbines as in a conventional power plant. Surplus energy is stored as heat, with a tank of synthetic oil serving as a reservoir for the high temperature (350^oC) heat needed to produce superheated steam, and a second system "downstream" to store heat at lower temperatures.

Such two stage thermal storage boosts the plant's efficiency, notes Zhihao Yao, a researcher at the Laboratory of Solar Thermal Energy in Beijing and member of the Dahan design team. The oil used in the Dahan storage system is also cheaper than the molten salts used to store heat at the Spanish facility, in part because the salts' high melting point means that such systems must be drained when the plant is not in use.

Favourable sign

Keeping costs down is important. "In China, the cost for using their own coal is unbeatable, unless you factor in the environmental damage," says Richter. Another snag is the large amount of land needed. David Faiman, director of Israel's Ben-Gurion National Solar Energy Center, notes that China's energy demand increased by about 430 terawatt–hours in 2007, and simply keeping up with this expansion would require devoting about 3000 km² of the Gobi desert each year to solar-thermal power. Still, the fact that China is investing in solar power on any scale is a "favourable sign", he adds.

The next step for the Chinese will be to enlarge the Dahan plant to 5–10 MW. This will happen by 2015, deputy project leader Li Xin toldhysicsworld.com. A separate 1000 MW plant is being planned for the Chinese province of Inner Mongolia, with support from Solar Millennium, the German firm that built the plant in Granada, but this commercial–scale facility is still a few years away.

About the author

Margaret Harris is Reviews and Careers Editor on Physics World

Salt-Free Solar: CSP Tower Using Air

2009-03-13T17:51:00.001-07:00

March 12, 2009

Concentrating solar power (CSP) is an emerging technology that offers the potential to supply utility-scale peaking power competitively.

by Mark Schmitz, Solar Institut Julich

London, UK [Renewable Energy World Magazine]

In December 2008, a 1.5 MWe solar thermal central receiver system was declared operational by plant construction company Kraftanlagen Munchen. Although solar tower technology had been built as early as the 1970s and a second commercial tower is now close to completion (see REW magazine July/August 2008) the so-called Test and Demonstration Power Plant Julich, in Germany, is the world's first solar thermal power plant erected which uses air as the medium for heat transport.

In all previous plants liquid media such as molten salt or oil have been used for the obvious reason of their high specific heat capacity, which in turn results in low volume flow rates and low pumping losses.

The great disadvantage of these concepts is that the solar radiation concentrated by the heliostat field to fluxes of 500 to 1000 suns is in air and that to transfer the heat it has to pass through a wall. This results in exchanger surface temperatures substantially higher than the fluid temperatures within. And, as the absorber surface faces the ambient environment it suffers thermal losses due to convection and – increasingly important for high temperatures according to the Stefan-Boltzmann law – re-radiation.

In contrast, the Jülich power tower uses the so-called volumetric effect to increase efficiency. Ambient air is sucked through a blackened porous structure on which the solar radiation is focused. The air cools the outer parts of the receiver and is heated up gradually to the design temperature level at the inner surface. Under ideal conditions, the temperature of the radiating outer surface can even be below that of the working fluid. Air also has the additional obvious advantages of being both environmentally benign and free.

The hot air is then fed into a state-of-the-art heat recovery steam cycle, conventionally used for the exhaust heat of gas turbines in combined cycle plants.

Professor Bernhard Hoffschmidt, Head of the Solar-Institute Jülich (SIJ) – part of the Aachen University of Applied Sciences – and initiator of the project, points out this implies another potentially big advantage, saying: 'Gas turbines driven by fossil or biogenous fuels are easily integrated into the solar system and can supply power at times of no solar radiation, allowing for 24 hour operation.' The SIJ is currently investigating different modes of hybridisation for various power levels and environmental conditions.

Alternatively, heat storage may be used to align supply and demand and the Jülich plant features a storage system consisting of honeycomb-type ceramic blocks, through which air passes in one direction for charging, and in the other for discharging. As the discharged air has the same temperature as when charging, no energy is lost, making the system highly efficient.

While considering the solar resource Jülich is not the ideal location for a solar power facility, it is when regarding the scientific and industrial resource. Situated in the Rhineland it is close to the German Aerospace Center (DLR), and the University of Aachen, with its institutes of high expertise regarding conventional power plants, as well as the SIJ. For that reason those mentioned have founded the Virtual Institute of Central Receiver Power Plants (vICERP) in order to set up a detailed dynamic simulation model of the power plant, used for testing advanced control strategies. A first enterprise has been founded aiming at the promotion of the technology.

This spring will see the first solar runs, but even today the list of up-coming improvements and innovations is long and many ideas are currently under investigation at the SIJ. These include:

New heliostat concepts and new means of control.
The absorber structure has been mainly designed for the reliability required of a prototype plant. In commercial plants designs with higher efficiencies can applied.
At the edge of the receiver, radiation of relatively low concentration is lost (the so-called spillage). Specially designed edge modules are to make use of this energy.
Storage concepts based on sand have been studied with promising results.
Custom-made boilers for the integration of gas turbines will be developed.

The biggest rise in efficiency, however, will be due to scaling up the plants to power levels where steam cycles can operate more efficiently. With big industry and foreign governments standing in line for the construction of the next plant, the step in this direction seems to be at hand.

Mark Schmitz is head of the Regenerative Systems unit of the Solar-Institut Jülich.

http://www.renewableenergyworld.com/rea/news/article/2009/03/salt-free-solar-csp-tower-using-air?src=rss

Plan To Set Up 10 MW Thermal Power Plant-Lucknow-Cities

2009-03-13T09:07:00.001-07:00

The Times Of India 21 Feb 2009

LUCKNOW: After inviting private concerns to set up coal fired thermal power plants, the UP Power Corporation Limited (UPPCL) is toying with the idea of setting up a solar thermal power plant in the state. The 10 MW plant, to be set up by a private company, is likely to come up in Unnao district.

Additional managing director, Narendra Bhooshan, in a letter sent to Aswani Kumar, director, ministry of non-conventional energy sources, government of India, on February 19 said that UPPCL has agreed in principal for installation of a 10 MW plant subject to terms set by UP State ElectricityRegulatory Commission (UPSERC).

According to the letter, M/s Power Cube Pvt Limited has indicated their interest in setting up a 10 MW plant in Unnao and have submitted their application for processing and finalising the power purchase agreement accordingly.

This would be the first such plant in the state once the UPSERC gives its nod to the power purchase conditions put forth by UPPCL. The commission had scrutinised the conditions on February 11. A final decision is yet to be taken on that regard.

The plant would work on the principle of conversion of sunlight into heat to boil water and turn a turbine to generate the electricity.

Chairman-cum-managing director, UPPCL, Navneet Sehgal said that the corporation is committed to encouraging the non-conventional sources ofenergy in the state. The corporation, had earlier asked the sugar mills owners to focus on energy production through bio-fuel. The mills, he said, would be given incentives and the problems faced by the mills would be solved.

UPPCL sources said that the power produced in the plant would be purchased directly by the corporation for being put into the northern grid. Small though, setting up of such a plant may herald a new era in the power production in the state which has largely restricted itself on conventional and exhaustible energy sources.

Ausra, United Technologies, Yeda R&D Among Leaders in Thermal Energy Storage Patent Landscape for Grid-Scale Concentrating Solar Thermal (CST)

2009-03-13T08:52:00.001-07:00

IP Checkups announces the release of its Sector Patent Landscape report entitled, Grid-Scale Concentrated Solar Thermal: Thermal Energy Storage Technologies. The report highlights key players, patents and filing trends in the emerging thermal energy storage patent landscape.

Berkeley, CA (PRWEB) February 26, 2009 -- IP Checkups' Sector Patent Landscape report, Grid-Scale Concentrated Solar Thermal: Thermal Energy Storage Technologies identifies key patent holders for important CST thermal energy storage solutions including compressed steam, phase-change materials and molten salt. The report concludes that in order to protect new grid-scale thermal energy storage technologies, companies must carefully navigate a handful of patents with broad claims as well as a significant body of non-patent literature.

According to the report, United Technologies (UTX), together with subsidiaries Hamilton-Sundstrand and Pratt & Whitney Rocketdyne, have obtained the broadest patent protection for molten salt thermal energy storage. SolarReserve is poised to take advantage of UTX's portfolio of patents through an exclusive licensing deal. In addition, a slew of up and coming companies and R&D labs including, Abengoa, Ausra, Bell Independent Power, Larkden Pty. Ltd., MeV Technology, SkyFuel, Solar Millennium, and Yeda Research & Development have aggressively filed patents on a variety of thermal storage technologies that will shape the patent landscape going forward.

Thermal energy storage is a key component to the long-term acceptance and success of grid-scale Concentrating Solar Power technologies (parabolic trough, linear fresnel, power tower, and dish-engine) by providing a means to remove the intermittent nature of the sun's energy and increase plant utilization. It is crucial for companies and investors to understand what technologies the key players in this space are protecting.

This 100 page in-depth Sector Patent Landscape Analysis identifies the fundamental patents, key players and emerging trends relating to patent coverage of various thermal energy storage technologies for CST applications. In all, 221 patent documents from the US, EP, JP and WO patent offices were uncovered that comprise the patent landscape.

The report breaks down the documents by filing date, geography, inventor, assignee and technology to identify key players, trends and fundamental patents in the field. In addition the report analyzes the level of patent protection including claims assessments, technology breadth and licensing agreements.

To learn more or purchase the report, visit www.ipcheckups.com/CST.

IP Checkups is a boutique Patent Analytics firm based in the Bay Area. The firm provides clients with customized competitive patent landscape analysis, technology sector overviews, and company patent portfolio profiles. IP Checkups' patent analysts combine traditional qualitative analysis with sophisticated software tools to dig deep into competitors' patent portfolios to understand how companies are positioned relative to each other in particular technology areas. Services include custom and off-the-shelf patent landscape overviews, company portfolio evaluations, patent monitoring and alerting services among others.

For more information contact Matthew Rappaport at (510) 981-1030 or visit www.ipcheckups.com.

Storing Solar Power in Salt

2009-03-13T08:47:00.001-07:00

By MATTHEW L. WALD

SolarReserve

What if it were possible to have solar power even when the clouds close in, or in the middle of the night? What if it were so reliable, it could fill the gap when the wind dies down and turbines stop spinning?

It's all possible, said Terry Murphy, president of SolarReserve. The company's design uses the sun's heat to boil water and spin a turbine — not unlike other "solar thermal" concepts that are now common. But where a typical system uses mirrors to concentrate sunlight and heat water; SolarReserve uses them to heat a salt, which melts into a liquid about twice as dense as water — and here's the catch: stored in thermal silo, the melted salt is able to maintain vast amounts of heat, which can be tapped later for use in power production.

The company received a second round of financing — $140 million — just last fall, and hopes to break ground next year.

SolarReserve's heat concentrators are not terribly different from other similar systems. It includes a tower that resembles a tall smokestack at a coal plant. At the top is a black cylinder that absorbs heat, and surrounding that are 17,000 mirrors, each six meters by seven meters, and each mounted on a stanchion that looks like a short lamp-post, and controlled by a computer that turns it to reflect sunlight unto the cylinder, regardless of season of the year or time of day.

The big difference is in the two storage tanks at the base of the tower. They can hold salt with enough heat to run the generators for hours. A demonstration deployment in the 1980s generated about 10 megawatts – enough to run about ten small shopping centers. The design SolarReserve hopes to break ground on next year would generate up to 300 megawatts.

"People talk about baseload capacity as the holy grail," Mr. Murphy said, referring to plants that can run dependably around the clock, supplying the minimum expected demand. "But the real holy grail is dispatchability,'' he said.

He compared it to pumped hydro, in which water is pumped up hill in the middle of the night, so it can run back down during the day when power is used. In this case, he said, it is "pumped solar."

A German company, Solar Millennium, is currently building a plant in Spain that also stores heat in molten salt. But the United States may be a better market, said Mr. Murphy, because prices paid by utilities vary so much; it might even pay to gather heat in the morning and sell it as electricity in the afternoon, when the prices — and demand — are much higher.

Mr. Murphy, who said he had 40 plants under development, also suggested that as the penetration of wind power increased, there would be more demand for "dispatchable" power from low-carbon sources, like his solar thermal design, when the wind stops blowing.

eSolar to build 1,000MW of solar power plants in India

2009-03-13T08:31:00.001-07:00

Published:06-March-2009

By Datamonitor staff writer

Names ACME as a master licensee of its modular, scalable technology and grants exclusive right to represent eSolar in India

eSolar, a producer of modular, scalable solar thermal power plants, has announced an exclusive licensing agreement with the ACME Group to build up to 1,000MW of solar thermal power plants in India over the next 10 years.

eSolar names ACME as a master licensee of its modular, scalable technology and grants the company the exclusive right to represent eSolar in India developing its own utility-scale solar thermal projects and working with other companies that want to build solar thermal power plants in India using eSolar technology.

The agreement combines both companies' resources to enable complete project capabilities, ranging from technology development and component manufacturing to power plant construction and operation. Additionally, ACME will make a $30 million equity investment in eSolar.

As a master licensee, ACME will build, own and operate solar thermal plants in India using eSolar's modular and scalable design and will work with other companies to build solar thermal power plants in India using eSolar technology. ACME has already signed power purchase memoranda of understanding for 250MW. Construction will start later in 2009 on the first 100MW of eSolar power plants.

Bill Gross, CEO of eSolar, said: "eSolar has produced the first solar energy that is competitive with fossil fuels. ACME's $30 million commitment demonstrates their confidence in eSolar's technology. We are committed to working with the very best partners, such as ACME, to scale deployment as quickly as possible around the world."

Solar-Thermal Energy Could Reduce Coal Plant’s Carbon Footprint

2009-03-13T08:24:00.001-07:00

FEBRUARY 12, 2009

Using solar-thermal technology at coal-fired power stations could turn out to be the cheapest way to simultaneously expand solar energy use and reduce coal plants' carbon footprint. Or at least that's what the Electric Power Research Institute (EPRI) is hoping to find out with a nine-month study, Technologyreview.comreports.

The nonprofit organization recently launched a $640,000 study to understand the scale of the opportunity and the engineering challenges involved with making the two technologies work together. The study will examine the potential use of solar-thermal technology at two coal-fired power stations in New Mexico and North Carolina.

Last month, five electric utilities in the U.S. and Canada joined EPRI to host studies of the impacts of retrofitting carbon capture technology to existing coal-fired power plants.

The idea is not entirely new: about six new and existing natural-gas power stations are being designed or adapted to incorporate solar-thermal technology. However, the overall efficiency of retrofitted hybrid solar-gas plants is still limited – when the sun goes down, a gas steam turbine that has been modified to accommodate waste heat plus solar heat will suffer an efficiency penalty from running at partial load.

However, for the hybrid technology to work, power plants will need a combination of strong sun and flat, open ground to host a solar thermal collector field. Moreover, governments need to put a firm price on carbon emissions from coal to justify trading cheap coal for more costly solar-thermal energy.

In January, EPRI noted that energy efficiency programs in the U.S. could realistically reduce the rate of growth for electricity consumption by 22 percent over the next two decades - if key barriers can be addressed.

Solar Water Heating Pays For Itself Five Times Over

2009-03-13T08:11:00.001-07:00

ScienceDaily (Mar. 13, 2009) — An analysis of the engineering and economics for a solar water-heating system shows it to have a payback period of just two years, according to researchers in India. They report, in the International Journal of Global Energy Issues, on the success of the 1000-liter system operating at a university hostel.

The current focus in the developed world is on advanced technological approaches to alternative energy sources, such as photovoltaic cells for solar power and harnessing wind and wave with elaborate systems to generate electricity. However, the cost of such systems may be prohibitive for some applications in the developing world. They also often ignore the fact that a mundane process such as heating water might best be carried out using direct heat from the sun rather than including a waste energy-conversion step.

Vivek Khambalkar, Sharashchandra Gadge, and Dhiraj S. Karale at the Dr Panjabrao Deshmukh Agricultural University, in Maharashtra, India, explain how they have evaluated the various costs and benefits involved in solar hot-water production. They have compared solar hot-water production per liter with electrical energy approaches and found that solar heating is 57 percent of the internal rate of return.

"Solar energy is the only renewable energy source that has wide range of uses with commercial viability. Solar energy provide water heating, air heating and electricity through various modes of applications. The use of solar energy for thermal purposes is the most cost-effective way of utilizing the resource. A solar water heating system satisfies the need of warm water," the researchers explain.

Importantly, the payback time for the initial investment in equipment and installation is just two years. This compares very well to a photovoltaic system used for electricity generation if it were only being used to heat water. Photovoltaics have a payback period of several at least a decade and sometimes double that.

The solar hot water system used in the study is installed at the Jijau hostel, part of the Dr Panjabrao Deshmukh Agricultural University campus, in Akola, Maharashtra state, India. The team estimates that the system will effectively pay for itself five times over, given an estimated working life of about twenty years.

Journal reference:

. Solar water cost and feasibility of solar water heating system. International Journal of Global Energy Issues, 2009, 31, 208-218

Adapted from materials provided by Inderscience Publishers, via EurekAlert!, a service of AAAS.

ACME to Invest $30 Million in eSolar for 5% Stake and Technology License to Develop 500 Megawatts in India

2009-03-12T22:52:00.001-07:00

ACME to Invest $30 Million in eSolar for 5% Stake and Technology License to Develop 500 Megawatts in India

BANGALORE, INDIA--March 12, 2009--Researched by Industrial Info Resources (Sugar Land, Texas)--ESolar (Pasadena, California), a developer of modular solar thermal power plants, recently entered into an exclusive licensing agreement with the ACME Group (Gurgaon, Haryana), a developer of innovative energy-efficient solutions, to develop up to 1,000 megawatts (MW) of solar thermal power stations in India over the next decade. ACME will invest $30 million for a 5% ownership stake in eSolar.

ACME has been named the master licensee of eSolar's modular technology and has been granted exclusive rights to represent eSolar in the Indian market. According to the licensing agreement, ACME will be permitted to use eSolar's modular, scalable technology to develop solar thermal projects in India by itself or in collaboration with partner firms. ACME has already entered into memorandums of understanding to buy 250 MW of solar thermal power. Construction of 100 MW of solar power plants based on eSolar's technology is expected to start later this year.

The agreement will enable the two firms to combine resources in project capabilities, technology development and component manufacture to develop and operate solar thermal power plants in India. The collaboration, which represents eSolar's first international licensing contract, is part of the firm's strategy to promote global deployment of its technology by entering into licensing agreements with local firms. ESolar is looking to license its technology in Australia, Spain and the Middle East.

The company claims to have developed an innovative technology for developing utility-scale concentrating solar power (CSP) plants ranging in capacity from 46 MW to more than 500 MW. ESolar's solution employs a field of heliostats that reflects solar heat to a thermal receiver mounted on a tower. The concentrated heat energy is used to boil water stored in the thermal receiver and produces steam. Steam is used to rotate a turbine, thereby generating power. The steam is then cooled to produce water and directed back to the thermal receiver, and the cycle continues. A 46-MW CSP unit based on the technology comprises 16 towers on which thermal receivers are mounted, a turbine and generator set and a steam condenser, spread over 160 acres of land area.

The sun-tracking heliostat is a mass-manufactured component and is the basic building block of the solution. The company has designed heliostats for easy deployment in pre-fabricated "heliostat sticks" that can be installed faster than other CSP solutions with minimal requirement of skilled labor. Thousands of heliostats are systematically spaced in a modular field layout that is optically designed to maximize the amount of solar power harnessed. This eliminates the need for high-precision surveying and individual installation and alignment of mirrors, thereby reducing the overall cost of power generation. The technology allows for multiple units of 46 MW each to be set up for higher power generation requirements. All these factors make eSolar's solution cost-competitive with traditional power plants based on fossil fuels. Coal-based power generation costs about U.S. 6 cents per kilowatt-hour (kWh), whereas the cost of solar thermal energy ranges from U.S. 8 cents per kWh to U.S. 15 cents per kWh.

ESolar was established in 2007 by Asif Ansari and Bill Gross, founders of Idealab Incorporated (Pasadena, California), an incubator founded in 1996. Idealab founded Picasa, which was acquired by Google (NASDAQ:GOOG) (Mountain View, California) in 2004. In April 2008, eSolar raised $130 million from Idealab, Google.org, the philanthropic arm of Google, and Oak Investment Partners (Palo Alto, California). The firm is currently developing a 5-MW plant in Lancaster, California, for commercial demonstration of its technology.

In February 2009, eSolar entered into an agreement with NRG Energy Incorporated (NYSE:NRG) (Princeton, New Jersey), a wholesale power generation firm, to develop solar power plants of up 500 MW in California and in the southwestern U.S. NRG Energy will invest $10 million in eSolar for an ownership stake, development rights to use eSolar's technology for three projects, and a technology license to develop, build and operate up to 11 CSP units in these regions based on eSolar's modular technology. The proposed power plants have an estimated capacity to provide 100% clean solar power to more than 400,000 homes in the region. The first of these plants, expected to come into operation in 2011, is a 245-MW project in Kern County in southern California for which eSolar had entered into a power purchase agreement last year with Edison International (NYSE:EIX) (Rosemead, California), one of the largest power distribution utilities in the state.

ESolar intends to utilize the cash inflow from its deal with ACME to fund its power development projects in the U.S. It plans to focus on developing utility-scale power plants in the U.S. while adopting the technology license route to make inroads in overseas markets. Because of the global economic recession and the credit crunch in the market, several of the firm's peers in Silicon Valley including Ausra (Mountain View) and OptiSolar (Hayward, California) are moving out of power plant construction projects and focusing on less-risky solar equipment sales. However, equipment sales are more susceptible to market fluctuations and face strong competition that drive down prices. On the other hand, despite heavy investments, successful power plant construction projects enable developers to draw a consistent stream of revenues through long-term contracts with utilities.

Founded in 2003, the ACME Group provides energy-efficient solutions in wireless telecommunications, wastewater treatment and cold-chain storage. ACME Tele Power Limited (Gurgaon), the group's flagship company, pioneered the "Green Shelter" concept, which provides management systems for optimal power utilization and cooling facilities at telecom sites without the use of backup systems such as diesel generators. The system is known to reduce operational costs by 40% compared to conventional shelters and reduces greenhouse gas emissions by saving about 2 million kWh of power and 100 million liters of diesel oil every year.

Industrial Info Resources (IIR) is a marketing information service specializing in industrial process, energy and financial related markets with products and services ranging from industry news, analytics, forecasting, plant and project databases, as well as multimedia services.

Review starts for Central Valley solar thermal-biomass plant

2009-03-11T18:37:00.001-07:00

COALINGA

March 11, 2009 12:08pm

• Would be built in Fresno County

• Could generate over 100 Megawatts

Architect's rendering of Martifer's Central Valley plant

The official review has started by the California Energy Commission for what is believed to be the first solar thermal-biomass hybrid electric generating facility in the state.

The commission on Wednesday found the application for certification of the 106.8-megawatt San Joaquin Solar 1&2 hybrid power plant project "data adequate."

This means the commission has received enough information from the applicant for the two plants, a wholly owned subsidiary of Martifer Inc. of San Francisco, a unit of Martifer Group of Lisbon, Portugal, to start the year-long certification process.

The commission has named Julia Levin to lead the committeec to review the project. Commission Vice Chairman James Boyd is the associate member.

The committee makes sure the project meets the requirements of the California Environmental Quality Act and will examine public health and safety, environmental impacts, and engineering aspects of the proposed power plant.

The project will be located six miles east of Coalinga in Fresno County. It will be comprised of two hybrid plants with a solar field and a biomass facility capable of producing 53.4 MW net of solar electricity each. During nighttime and periods of cloud cover, the solar production will be supplemented by the biomass facility fueled by agricultural wood waste.

If approved by the commission, the project is expected to be on line by the first quarter of 2011.

How to Use Solar Energy at Night

2009-02-18T17:20:00.001-08:00

Features - February 18, 2009

Molten salts can store the sun's heat during the day and provide power at night

By David Biello

Near Granada, Spain, more than 28,000 metric tons of salt is now coursing through pipes at the Andasol 1 power plant. That salt will be used to solve a pressing if obvious problem for solar power: What do you do when the sun is not shining and at night?

The answer: store sunlight as heat energy for such a rainy day.

Part of a so-called parabolic trough solar-thermal power plant, the salts will soon help the facility light up the night—literally. Because most salts only melt at high temperatures (table salt, for example, melts at around 1472 degrees Fahrenheit, or 800 degrees Celsius) and do not turn to vapor until they get considerably hotter—they can be used to store a lot of the sun's energy as heat. Simply use the sunlight to heat up the salts and put those molten salts in proximity to water via a heat exchanger. Hot steam can then be made to turn turbines without losing too much of the original absorbed solar energy.

The salts—a mixture of sodium and potassium nitrate, otherwise used as fertilizers—allow enough of the sun's heat to be stored that the power plant can pump out electricity for nearly eight hours after the sun starts to set. "It's enough for 7.5 hours to produce energy with full capacity of 50 megawatts," says Sven Moormann, a spokesman for Solar Millennium, AG, the German solar company that developed the Andasol plant. "The hours of production are nearly double [those of a solar-thermal] power plant without storage and we have the possibility to plan our electricity production."

Using mirrors to concentrate the sun's energy is an old trick—the ancient Chinese and Greeks both used it to start fires—and modern power plants employing it might provide a significant source of renewable energy without any greenhouse gas emissions.

That is a step forward in its own right, but such power plants are limited to generating energy only when there is sunshine. So engineers have tried a number of different technologies to store the sun's energy so that such power plants can be more broadly employed. They have tried batteries but too much of the energy that goes in is not returned, and they tend to be too expensive, according to an analysis from the National Renewable Energy Laboratory (NREL) in Golden, Colo. Compressing air or pumping water uphill are more promising, but the opportunities to do that are limited by the number of caverns and the availability of water and reservoirs.

Melting salts at temperatures above 435 degrees Fahrenheit (224 degrees Celsius), however, can deliver back as much as 93 percent of the energy, plus the salts are ubiquitous because of their application asfertilizers.

"There's a term called round-trip efficiency. Basically, it's a measure of how much electricity is produced if the thermal energy that's generated is first stored and then used compared to just directly taking the energy. That number is around 93 percent," explains NREL senior engineer Greg Glatzmaier. "[For] things like compressed air and mechanical type storage, there's more significant losses," an average of at least 20 percent over all the various technologies.

The Andasol 1 power plant, which cost around $380 million (300 million euros) to build, is the first to actually use the technology, so it remains to be seen how it will work in commercial practice. But U.S. government laboratories—NREL as well as Sandia National Laboratory in Albuquerque, N.M.—have already proved the technology can work in demonstration projects that employed it, like the Solar Two power tower outside Barstow, Calif.

Solar Millennium is so confident the technology will work that a twin solar-thermal power plant (Andasol 2) is already near completion. "It will start operations at the beginning of summer—May or June," Moormann says.

And Arizona Public Service Co. (APS) has contracted with Abengoa Solar to build a 280-megawatt solar thermal power plant—dubbed Solana or "sunny place"—70 miles (110 kilometers) southwest of Phoenix on nearly 2,000 acres (800 hectares) of land. "One of the great things about molten salt technology is that you can get more out of the pure solar resources, more energy out of the same facility," says Barbara Lockwood, manager for renewable energy at APS. "It's an alternative that provides us with additional green energy," as much as 1,680 megawatt-hours when cloudy or after sunset.

But that extra energy comes at a cost. First, the power plant has to be enlarged so that it is both generating its full electrical capacity as well as heating up the salts. In the case of Andasol 1 that meant covering 126 acres (50 hectares) with long rows of troughs and pipe. And then there is the additional expense of the molten salt storage tanks, according to Moormann.

All told, that means thermal energy storage at Andasol 1 or power plants like it costs roughly $50 per kilowatt-hour to install, according to NREL's Glatzmaier. But it doesn't add much to the cost of the resulting electricity because it allows the turbines to be generating for longer periods and those costs can be spread out over more hours of electricity production. Electricity from a solar-thermal power plant costs roughly 13 cents a kilowatt-hour, according to Glatzmaier, both with and without molten salt storage systems.

That price is still nearly twice as much as electricity from a coal-fired power plant—the current cheapest generation option if environmental costs are not taken into account. But Arizona's APS and others can then use solar energy to meet the maximum electricity demand later in the day. "Our peak demand [for electricity] is later in the evening, once solar production is trailing off," Lockwood says. That's "the reason we went that direction and are so interested in storage technology."

As efficient as solar-thermal power plants using parabolic troughs with molten salt storage systems like Andasol 1 or Solana are, they don't capture as much of the sun's heat as is possible. Above 750 degrees F (400 degrees C), the synthetic oils used to capture the sun's heat in the troughs begin to break down, but the molten salts can take in much more heat than that.

To allow the salts to get hotter, some companies, such as SolarReserve in Santa Monica, Calif., are developing so-called power towers—vast fields of mirrors that concentrate sunlight onto a central tower. Because of the centralized design such a structure can operate at much higher temperatures—up to 1,000 degrees F (535 degrees C)—and use molten salts directly as the fluid transferring heat in the power plant. "We are heating the salts to more than 1,000 degrees F and that results in the same inlet conditions that utilities see today on a coal-fired or nuclear power plant," says Terry Murphy, SolarReserve's president.

But such a power plant—and Murphy says the company has some 50 such projects in the pipeline and expects at least one (in the U.S. or Spain) to be operating by 2013—would cost as much as $800 million for a 200-megawatt power tower. "The first molten salt power tower built is going to be a real trial," says Thomas Mancini, manager of Sandia's Concentrating Solar Power Program. "It's going to take someone progressive enough to finance it or take a little more risk."

So researchers are also looking into salts that could be used instead of the oil in parabolic trough power plants, such as those that melt at lower temperatures and therefore would not freeze as readily during cold nights, according to Hank Price, a vice president for technology development at Abengoa Solar.

Solar Millennium is working on such a salt, according to Moormann, and Sandia has developed small quantities of a new mixture of salts, including calcium nitrate and lithium nitrate, that melt below 212 degrees F (100 degrees C). "With the lithium nitrate, it's as expensive as all the other constituents combined. Though still a lot cheaper than organic heat-transfer oils," says chemical engineer Bob Bradshaw at Sandia in California, who is leading the research. "You don't get something for nothing."

And long-term research projects are looking at other thermal storage technologies, such as storing heat in sand or creating single-tank molten salt storage. "The main goal is to find a storage technology that may reduce the actual capital cost" of adding it to a power plant, says Phil Smithers, technical services leader for renewable energy at APS, which is researching those technologies under a U.S. Department of Energy grant.

Ultimately, it will come down to how much value policymakers and consumers put on electricity that is renewable and emissions-free. "If we start valuing carbon and force a coal plant to go carbon-free via sequestrationthen we're at or over 10 cents per kilowatt-hour from coal," Mancini says. "Any of these technologies can get to that same 10 cents level with [molten salt] storage. Then the market will make the call."

And should Andasol 1 spring a leak or otherwise fail to deliver as expected, the damage would not be confined to a pile of salt fertilizer on the ground—it could be a setback for the entire effort to store solar energy. "We had to build the first [commercial] plant [with molten salt storage] and that's what Andasol is," Mancini says, in order to prove the technology. "It doesn't have to be perfect, but they've got to make it work."

Israel's renewable-energy dreams set to awaken at Eilat parley

2009-02-01T19:51:00.001-08:00

Feb. 1, 2009
WESLEY PINKHAM and MATTHEW KRIEGER , THE JERUSALEM POST

It is not news that the US government has consistently supported Israel as its primary economic and diplomatic partner in the Middle East. But the reasons for continued investment in the region are based on more than lofty democratic and ideological similarities. American dollars sent to Israel have resulted in stable and significant returns on investment. That this economic partnership is now expanding into the field of alternative energy comes as no surprise.

From the wispy, year-round winds in the North to the sun-drenched desert in the South, Israel's climate and technological ingenuity are proving to be successful launching points for a widespread and sustainable green-energy movement. The US government and private investors - Americans and Israelis - have taken note of this and have already begun investing deeply, both monetarily and politically.

In July 2006, the US House of Representatives voiced its approval for HR 2730, the United States-Israel Energy Cooperation Act, which will authorize funding for joint ventures between US and Israeli businesses in the alternative-energy sector. The cooperative partnership is expected to be launched at the Eilat-Eilot International Renewable Energy Conference this February 17-19. It seeks to invest millions of US dollars in "research, development, or commercialization of alternative energy, improved energy efficiency, or renewable energy sources."

The conference will serve as a forum for local and international sustainable-energy leaders to plan the future of the renewable-energy market. It will feature local Israeli businesses, including: Arava Power Company, a firm that is trying to get 10 percent of Israeli households powered by solar technology, primarily through alliances and land owners; and AORA, a leading developer of applied ultra-high-temperature-concentrating solar power (CSP) technology.

AORA recently announced that it has begun construction on the world's first gas-turbine solar thermal-power station in Israel at Kibbutz Samar in the Arava. The company's modular energy-generating system is designed to require less land while generating more usable power and heat at a lower cost than other solar-energy systems; its revolutionary hybrid approach enables the system to run on solar-radiation input and almost any alternative fuel, including biogas, biodiesel and natural gas, guaranteeing an uninterrupted green-power supply 24 hours a day.

During the conference, AORA will conduct an exclusive tour of its Samar power station, which is scheduled to be completed by the end of March. The power station is situated on two dunams of land in the Arava and consists of a field of 30 tracking mirrors (heliostats).

Each heliostat will follow the sun and direct its rays toward the top of a 30-meter-high tower housing a special solar receiver along with a 100-kilowatt gas turbine. The patented receiver will use the sun's energy to heat air to a temperature of 1,000 degrees Celsius and direct this energy into the turbine. The turbine will in turn convert this tremendous thermal energy into electric power that will be fed directly into the national grid.

The international business community has also taken notice, with names such as Google-backed eSolar and German-based Concentrix attending. Last week, Deutsche Bank, one of the world's largest and most well-respected financial institutions, formally announced its intention to seek renewable-energy partnerships and investments with both local and international companies who will be attending the event.

"We enthusiastically support the future growth of the Israeli renewable energy industry and very much look forward to taking an active role in its development," said Boaz Schwartz, Deutsche Bank's managing director for Israel. "I strongly believe that the combination of efficient utilization of natural resources and advanced technologies, coupled with Deutsche Bank's know-how and experience, is a win-win proposition for the renewable-energy markets here in Israel and around the world."

Deutsche Bank is very active in the global renewable-energy arena and has been involved with numerous energy projects as a financial advisor and an equity investor.

The news was met with much excitement, with renewable-energy leaders hailing it as a landmark moment for the development of the country's local energy market.

"Through their pursuit of investments in Israeli infrastructure and Israeli technology, Deutsche Bank is underscoring its commitment to advancing the local renewable-energy industry," said Shimon Klein, managing partner of Jerusalem-based EZKlein Partners, a leading renewable-energy service provider. "To have a company such as Deutsche Bank actively invest in the growth of the Israeli energy market is a very significant and important milestone for the local sector."

The Deutsche Bank announcement follows the statement released last week by SCHOTT Solar, another large German-based corporation, which said it would use the event to officially launch its Israeli operations. With more than 50 years of experience in the solar market and 18,000 employees, SCHOTT Solar has targeted Israel and its history as a technological pioneer as a great opportunity to expand its business.

The conference also will focus on the development of the Timna Renewable Energy Park initiative, a huge undertaking that will be this country's "alternative-energy Silicon Valley."

Israel suffers from hostile relations with many oil-producing countries, and a consistent flow of oil and natural gas is of great concern. These same geopolitical issues have become critical for Western countries. Major resources are held at the whim of tumultuous regimes. The war in Iraq was at least partially motivated by this fear of limited resources.

Sustainable, alternative energy has become so widely accepted as the way of the future in the US that even writing about its importance has become cliché. In Israel, we are slowly coming to the realization that alternative energy is a major stabilizing force, both outside and inside the Middle East.

By developing a sustainable-energy infrastructure and market, Israel can be freed from the shackles of foreign oil and further develop its own economic independence. The recent issuing of the country's first solar licenses is a sign that the government is finally catching on to the importance of harnessing and developing the country's renewable energy resources.

Israel currently boasts more than 600 companies in the clean-tech industry, many of which have already made significant advances in solar energy, utilization and management of water resources, geothermal technologies, energy management and conservation and desertification. These advancements are partly attributable to Israel's academic institutions, which boast the highest number of PhDs per capita.

Like its desertification efforts, Israel continues to create something out of nothing, to sustain the unsustainable. These efforts will take a major step forward at the conference. While Israel may be lacking in water resources, the southern part of the country is drenched almost year-round with an abundance of sun. Harnessing this natural resource presents the country with both a unique challenge and immense opportunity.

"Let there be light."

wpinkham@ucla.edu

mattkrieger@gmail.com

Wesley Pinkham is a student at University of California, Los Angeles, where he majors in world arts and cultures. He is currently studying at the Hebrew University of Jerusalem.

Matthew Krieger is a senior account executive at Ruder Finn Israel and a former business and economics reporter for The Jerusalem Post.

Acme to set up 100MW solar thermal power plant

2008-12-10T01:24:00.001-08:00

Published on Dec 8, 2008
Acme Energy Solutions plans to set up India's first 100MW solar
thermal power plant.

N. Venkataraman, executive vice president of the company's energy
solutions division, reportedly said that Acme plans to set up a 100MW
solar thermal project either in Rajasthan or Gujarat in about a year.
Venkataraman told IANS that the cost of power generated by his company
would be among the lowest for solar thermal plants. "The cost of
electricity would be around Rs. 8 per unit (US$1 = Rs. 50 approx.),
which is among the lowest in the world for such kinds of projects," he
reportedly said.

In August this year, the Ministry of New and Renewable Energy, too,
had indicated about Acme's plans.

The Ministry has also been suggesting to various Central Ministries
and Government departments to maximise the use of solar energy devices
and systems at their establishments.

To encourage participation of the private sector for development of
solar energy, the Ministry is providing various fiscal and financial
incentives which include soft loans to manufactures for technology
up-gradation, concessional or nil duty on import of various equipment,
exemption of excise duty, accelerated depreciation, generation based
incentive for setting up of grid power plants based on solar thermal
and photovoltaic technologies etc.

The quantum of subsidy / support being given to the private sector
includes: Soft loan at an interest rate of five percent to
manufactures through IREDA for technology up-gradation on solar water
heating systems; Up to Rs.10/- per KWh for electricity generated from
solar thermal and Rs.12/- per KWh from solar photovoltaic power plants
of capacities 1 MW and above.

Source:CSP Today

BrightSource Energy Signs Contract With Siemens for Largest Ever Fully Solar-Powered Steam Turbine Generator

2008-12-10T01:21:00.001-08:00

Turbine Generator to Be Operated at BrightSource's Ivanpah Solar Power Complex

Last update: 6:00 a.m. EST Dec. 9, 2008

OAKLAND, Calif., Dec 09, 2008 (BUSINESS WIRE) -- BrightSource Energy,
Inc., developer of large-scale solar thermal energy plants, has signed
a contract with Siemens to purchase the steam turbine generator for
BrightSource's first 100MW plant at its Ivanpah Solar Power Complex in
California's Mojave Desert. The purchase marks another key step in
BrightSource Energy's path to construct the state's first large-scale
solar thermal power plant in nearly thirty years.
The contract with Siemens is for the supply of a 123 MW fully
solar-powered steam turbine generator. When completed, the turbine is
expected to be the largest fully solar-powered steam turbine generator
to date.
"This contract marks another significant milestone in building
California's first large scale-solar power plant in decades," said
John Woolard, CEO of BrightSource Energy. "The Siemens high quality
solar-powered turbine generator offers additional certainty that the
project will deliver cost effective, reliable, and clean solar power."
Due to a lengthy production process, turbine generators must be
ordered approximately three years in advance of the planned delivery
date. The Siemens turbine is slated to be delivered in early 2011, and
BrightSource expects this first phase of its Ivanpah Solar Power
Complex to be operational and supplying solar energy to utilities in
the fourth quarter of 2011.
"Our extensive experience in optimizing our steam turbines for solar
thermal applications puts us in a leading position to help customers
provide clean solar power," says Markus Tacke, CEO of the Siemens
Energy Oil & Gas Division's Industrial Applications, Steam Turbines
business unit. "Siemens is proud to be building the largest fully
solar-powered steam turbine generator to date for BrightSource's
Ivanpah solar power plant."
BrightSource's Ivanpah Solar Power Complex will be comprised of three
separate solar plants and will produce a combined total of 400 MW of
power. Upon completion, the Ivanpah Solar Power Complex will produce
enough clean energy to power the homes of 140,000 PG&E customers and
reduce carbon dioxide (CO2) emissions by over 500,000 tons per year.
BrightSource is scheduled to begin construction on the Ivanpah site in
2009.
BrightSource Energy's solar thermal energy plants are built on the
company's proven Luz Power Tower (LPT) technology. The system uses
thousands of small mirrors called heliostats to reflect sunlight onto
a boiler atop a tower to produce high temperature steam. The steam is
then piped to a conventional turbine inside a power block, which
generates electricity. The electricity is then connected to the
transmission grid for consumption. The steam is air-cooled and piped
back into the system in a closed-loop, environmentally friendly
process.
This fully integrated energy system offers the highest operating
efficiencies and lowest capital costs in the industry. The result is a
large-scale solar system that reliably delivers solar energy at a cost
competitive with fossil fuels.
BrightSource has achieved numerous milestones in the past nine months.
In March, BrightSource entered into a series of power purchase
agreements with PG&E for up to 900MW of electricity. In May,
BrightSource announced that it had secured $115 million in additional
corporate funding from its Series C round of financing, bringing the
total the company has raised to date to over $160 million. In June,
BrightSource dedicated their Solar Energy Development Center (SEDC),
an operational solar field that will provide the company with the
ability to test equipment, materials and procedures as well as
construction and operating methods.
For its technological leadership, the company was recently selected as
a 2009 Technology Pioneer by the World Economic Forum. The only solar
company to win this year's prestigious award, BrightSource Energy was
recognized for helping global utility and industrial customers reduce
their dependence on fossil fuels by providing clean, low-cost and
reliable solar energy.
About BrightSource Energy, Inc.
BrightSource Energy, Inc. provides clean, reliable and low cost solar
energy for utility and industrial companies worldwide. The
BrightSource Energy team has more than thirty years of experience
designing, developing, and operating solar energy plants. BrightSource
Energy helps its customers reduce their dependence on fossil fuels and
is a leader in environmental stewardship. Headquartered in Oakland,
Calif., BrightSource Energy is a privately held company with
operations in the United States and Israel. To learn more about
BrightSource Energy and solar thermal energy, visit
www.brightsourceenergy.com.
(C) BrightSource Energy, Inc. All rights reserved. All trademarks are
the property of their respective owners.
SOURCE: BrightSource Energy, Inc.
Hill & Knowlton for BrightSource Energy
Kristin Hunter, 415-281-7161
kristin.hunter@hillandknowlton.com

Largest Solar Thermal Storage Plant to Start Up

2008-10-03T08:24:00.001-07:00

By Peter Fairley

PHOTO: SOLAR MILLENNIUM
1 October 2008—A few weeks from now, the Andasol 1 solar thermal power
plant in Andalucía, Spain, will begin charging the largest
installation built expressly for storing renewable energy (other than
the tried-and-true hydroelectric dam, of course). Heat from the solar
thermal power station's 510 000-square-meter field of solar collectors
will be stored in 28 500 tons of molten salt—enough to run the plant's
50-megawatt steam turbine for up to 7.5 hours after dark.

It's pretty strange for solar power to generate electricity in the
dark. Stranger still for a renewable-energy project is the fact that
Andasol 1's developers—German renewable-energy firm Solar Millennium
and Madrid-based engineering and construction firm ACS/Cobra—believe
the energy storage that makes the plant's output more predictable will
also make it more affordable. The developers say Andasol 1's
electricity will cost 11 percent less to produce than a similar plant
without energy storage—dropping from 303 euros per megawatt-hour to
271 euros per MWh.

The lower cost of production is actually a by-product of Andasol 1's
energy-storage system, according to Paul Nava, a managing director of
Flagsol GmbH, the Cologne, Germany–based engineering subsidiary of
Solar Millennium that designed the plant. Nava says storage is a means
of maximizing the net energy production from each plant and thus
maximizes the revenues paid under Spain's generous incentive program
for renewable-energy generation. A feed-in tariff for solar thermal
power pays 2.5 to 3 times the average power price for every MWh of
energy generated for 25 years (though new rules will reduce the rate
for future projects) but limits the capacity of qualifying facilities
to 50 MW. Storage enables Andasol 1 to run its 50-MW turbine for more
hours.

Nava estimates that Andasol 1 will generate 178 000 MWh of renewable
electricity per year, whereas the same field of solar collectors and
turbine would turn out just 117 000 MWh sans storage—a difference
worth more than 24 million euros per year (US $36 million) at today's
power prices.

At Andasol 1, generating this clean energy surplus starts with 24
kilometers of trough-shaped mirrors concentrating sunlight on solar
collector tubes and heating the synthetic oil flowing within as high
as 400 degrees Celsius (the safety and durability limit for the oil).
To put power on the grid, hot oil is circulated to the plant's "power
block," where the heat is converted to steam and drives the turbine.
However, when the sun is strongest, Andasol 1's oversized collector
field should gather almost twice as much heat as the turbine can
handle. This extra heat will be dumped into the storage system: a heat
exchanger connecting two insulated storage tanks, each 14 meters high
and 36 meters in diameter, holding molten potassium and sodium nitrate
salt.

The tanks are kept at different temperatures. Molten salt pumped from
the "cold" tank (maintained at a not-so-chilly 260 °C to keep the salt
molten) into the heat exchanger picks up heat from the oil and then
flows into the hot tank (which will reach 400 °C when fully charged).
To discharge the stored energy, the process is reversed, with molten
salt pumped from the hot tank to the cold tank to reheat the oil.

One problem with running a molten-salt storage system is that the salt
could freeze during cold snaps, necessitating an injection of heat
that reduces the plant's power output. But Nava says Andasol 1 has
some improvements over earlier experimental designs to minimize the
need to warm the salt. Andasol 1's valves are fewer in number, and
both the valves and the heat exchanger are designed to drain when not
in use, eliminating the need to keep them hot. The pumps, which cannot
be drained regularly, sit submerged within the tanks instead of
outside the tanks, where they would have to be heated separately. Nava
estimates that, overall, annual energy losses from the storage system
will be just 5 percent.

More such plants are on the way in Spain. Solar Millennium and its
Spanish partner expect to start up a twin plant, Andasol 2, next
spring and plan to begin building a third 50-MW plant early next year.

Spain's Abengoa Solar and Sener, meanwhile, are each testing solar
thermal plants with integrated molten-salt storage. Both use a "power
tower" configuration in which arrays of mirrors direct sunlight onto a
central solar receiver where the light directly heats a molten salt.
This configuration matches that of Solar Two, a 10-MW solar thermal
demonstration plant at Sandia National Laboratories, in New Mexico,
built in the 1990s. The power-tower design makes energy storage
cheaper and more compact because the salts can be safely heated well
beyond the limit of the synthetic oils.

"Using the molten salt as both the working and storage fluid gave us
high heat capacity," says Sandia concentrating solar-power program
manager Thomas Mancini. "Instead of 260 °C to 390 °C, you're going
from 260 °C to 560 °C. It's a bigger temperature difference, so you
need less salt to store the same amount of energy."

At present, most of the anticipated U.S. solar thermal projects, which
are driven by state-level renewable-energy mandates rather than a rich
feed-in tariff, are focused on minimizing upfront costs, and few
projects plan to integrate energy storage. But Mancini and Nava say
that may change as utilities adopt time-of-day electricity pricing.

Nava says a pricing scheme already introduced by Southern California
Edison should encourage what he calls a "solar booster" thermal power
plant. The California utility pays 3.28 times its base rate for
electricity delivered between noon and 6 p.m. on summer weekdays. A
solar booster would use an undersized collector field and storage to
focus generation on that sweet spot. "In the morning, you use the
solar field only to charge the storage, and then from noon on, when
you have that factor of three for the electricity rate, you discharge
the storage and use the field in parallel to drive the steam turbine,"
says Nava.

About the Author
Contributing Editor Peter Fairley has reported for IEEE Spectrum from
Bolivia, Beijing, and Paris. In May 2008 he wrote for us about China's
rapid gains in wind power.

SPV Data from Earth Policy Institute

2008-09-04T04:54:00.001-07:00

World Annual Photovoltaic Production, 1975-2007 (figure and table)

World Cumulative Photovoltaic Production, 1975-2007 (figure and table)

Annual Photovoltaic Production, Select Countries and Europe, 1995-2006 (figure and table)

Annual Thin Film Photovoltaic Production, Select Countries and Regions, 2003-2006 (figure andtable)

Annual Photovoltaic Installations, Select Countries and Regions, 2000-2007 (figure and table)

Photovoltaic Production by Top Ten Producing Companies, 2006 and First Half of 2007 (table)

World Average Photovoltaic Module Cost per Watt, 1975-2006 (figure and table)

World Photovoltaic Production, 1975-2007
Year	Annual Production	Cumulative Production
	Megawatts
1975	2	2
1976	2	4
1977	2	6
1978	3	9
1979	4	13
1980	7	20
1981	8	28
1982	9	37
1983	17	54
1984	22	76
1985	23	99
1986	26	125
1987	29	154
1988	34	188
1989	40	228
1990	47	275
1991	55	330
1992	58	388
1993	60	448
1994	69	517
1995	78	594
1996	89	683
1997	126	809
1998	155	964
1999	201	1,165
2000	277	1,442
2001	386	1,828
2002	547	2,375
2003	748	3,123
2004	1,194	4,317
2005	1,786	6,103
2006	2,521	8,623
2007	3,800	12,423
Source: Compiled by Earth Policy Institute from Worldwatch Institute, Vital Signs 2005(Washington, DC: 2005); Worldwatch Institute, Vital Signs 2007-2008 (Washington DC: 2008); Prometheus Institute, "23rd Annual Data Collection - Final," PVNews, vol. 26, no. 4 (April 2007), pp. 8-9; REN21, Renewables 2007 Global Status Report: A Pre-Publication Summary for the UNFCCC COP13 (Paris: December 2007).

Annual Photovoltaic Production by Country, 1995-2006
Year	United States	Japan	Europe	China	Taiwan	India	Others	Total
	Megawatts
1995	34.8	16.4	20.1	NA	NA	NA	NA	77.7
1996	38.9	21.2	18.8	NA	NA	NA	NA	88.7
1997	51.0	35.0	30.4	NA	NA	NA	NA	125.8
1998	53.7	49.0	33.5	NA	NA	NA	NA	154.9
1999	60.8	80.0	40.0	NA	NA	NA	NA	201.3
2000	75.0	128.6	49.8	2.5	NA	10.5	10.5	276.8
2001	100.3	171.2	73.9	3.0	3.5	12.5	21.6	386.0
2002	120.6	251.1	122.1	8.0	8.0	19.1	18.2	547.1
2003	103.0	363.9	200.2	9.0	17.0	23.1	32.2	748.4
2004	138.7	601.5	311.8	35.0	40.0	31.1	35.4	1,193.5
2005	154.0	833.0	476.6	134.0	88.0	35.5	65.0	1,786.1
2006	201.6	926.9	678.3	369.5	177.5	43.4	123.6	2,520.8
Note: NA = not available or negligible.
Source: Compiled by Earth Policy Institute from Worldwatch Institute, Signposts 2004, CD-Rom (Washington, DC: 2005); Prometheus Institute, "23rd Annual Data Collection - Final,"PVNews, vol. 26, no. 4 (April 2007), pp. 8-9.

Annual Thin Film Photovoltaic Production, 2003-2006
Year	United States	Japan	Europe	Rest of World	Total
	Megawatts
2003	14.1	5.0	7.7	6.0	32.8
2004	23.0	17.5	15.6	7.0	63.1
2005	46.0	36.2	19.6	6.0	107.8
2006	92.5	54.7	12.4	11.0	170.6
Source: Prometheus Institute, PVNews, vol. 26, no. 4 (April 2007), p. 10.

Annual Photovoltaic Installations, Select Countries and Regions, 2000-2007
Country/Region	2000	2001	2002	2003	2004	2005	2006	2007
	Megawatts
Germany	44.0	78.0	80.0	170.0	500.0	700.0	1,050.0	1,260.0
Japan	74.4	91.0	141.0	201.0	256.0	320.0	350.0	402.5
United States	16.8	28.4	49.1	71.7	89.9	108.0	141.4	259.0
Rest of Europe	1.0	3.0	10.0	11.0	24.0	60.0	118.0	234.0
Rest of Asia	13.0	19.0	43.0	33.0	47.0	55.0	81.0	131.9
Note: Installations for 2007 are estimates.
Source: Travis Bradford and Paul Maycock, "PV Market Update: Demand Grows Quickly and Supply Races to Catch Up," Renewable Energy World, July 2007.

Photovoltaic Production by Top Ten Producing Companies, 2006 and First Half of 2007
Company	2006	First Half of 2007
	Megawatts
Sharp (Japan)	434	225
Q-Cells (Germany)	253	160
Suntech (China)	158	145
Kyocera (Japan)	180	108
Sanyo (Japan)	155	87
Motech (Taiwan)	102	85
Deutsche Solar/Shell (United States, Germany)	86	66
First Solar (United States)	60	61
Mitsubishi (Japan)	111	55
SunPower (Philippines)	63	54
Source: Prometheus Institute, "Asian Cell Producers Swamping the Boat: A Look at the First Half of 2007," PVNews, vol. 26, no. 9 (September 2007), pp. 6-8.

World Average Photovoltaic Production and Module Cost per Watt, 1975-2006
Year	Annual Production	Cost per Watt
	Megawatts	2007 U.S. Dollars
1975	2	99.61
1976	2	78.39
1977	2	58.92
1978	3	41.18
1979	4	32.89
1980	7	27.79
1981	8	21.16
1982	9	17.92
1983	17	14.80
1984	22	12.88
1985	23	10.68
1986	26	8.67
1987	29	6.73
1988	34	7.30
1989	40	7.40
1990	47	7.47
1991	55	7.18
1992	58	6.29
1993	60	5.79
1994	69	5.32
1995	78	5.33
1996	89	5.11
1997	126	5.26
1998	155	4.71
1999	201	4.29
2000	277	4.21
2001	386	3.79
2002	547	3.73
2003	748	3.65
2004	1,194	3.55
2005	1,786	3.70
2006	2,521	3.84
Note: 2001 and 2003 prices are estimated by Earth Policy Institute.
Source: Compiled by Earth Policy Institute from Worldwatch Institute, Vital Signs 2001(Washington, DC: 2001); Paul Maycock, "Boomer," PVNews, July 2007, p. 12. Prices adjusted to 2007 dollars using U.S. Department of Commerce, Bureau of Economic Analysis, "Implicit Price Deflators for Gross Domestic Product," atwww.bea.gov/bea/dn/nipaweb/TableView.asp#Mid.

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Nagpur to have Asia's biggest solar thermal power plant

2008-09-04T04:27:00.001-07:00

Nagpur (PTI): The second capital of Maharashtra will soon have the privilege of having a 10 mw solar thermal power plant, which will be the biggest such plant in entire Asian continent, thanks to the initiative of union ministry of new and renewable energy.

" The unique 10 mw solar thermal generation facility will also serve the purpose of demonstration for solar energy enthusiasts across the country, being the only plant coming up here," Union Minister for New and Renewable Energy, Vilas Muttemwar told PTI.

Nagpur has been selected because of high sun radiation besides its central geographical location, the minister said adding the solar energy generated is environmental friendly and free from any polution.

Moreover, there are no transmission and distribution losses unlike the traditional methods of coal-fired energy in most electricity generation units.

The plant load factory is between 80 to 90 percent of the installed capacity, he said.

" The generated power will be put on the national grid. It's small step but a big leap in solar energy generation world," Muttemwar, the lone congress MP from entire Vidarbha said.

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