Standing out in the increasingly crowded solar energy space isn't easy these days. But Australian-American startup Ausra seems to have managed to do just that. Named after an ancient Indo-European goddess of the dawn, Palo Alto, California-based Ausra is a solar thermal technology company that, unlike many of its rivals, touts a means to produce electricity from sunlight that requires less fuss than conventional methods and could lower the cost of generating utility-scale power.
"You'd be mad to build a gas plant or a coal plant when there are technologies like this around," said CEO Peter Le Lièvre, who helped form the company late last year. Solar thermal power plants capture heat from sunlight and use it to generate electricity.
Ausra uses relatively inexpensive 40-foot-long flat plate mirrors–called Fresnel reflectors–to concentrate the sun's rays directly on water pipes, boiling the water to run steam turbines, which, in turn, generate electricity, according to a company representative. The system, which the company says has the potential to generate electricity for two-thirds the cost of its competitors, has attracted more than $40 million in funding from Khosla Ventures and Kleiner Perkins Caufield & Byers, Ausra said Monday.
Concentrated solar power plants generally use trough-like structures whose curved mirrors focus sunlight onto tubes of oil. The heat from the oil is then used to create steam and to drive the electricity-generating turbine. But the mirrors must be precisely shaped and mounted on sun-tracking devices, requirements that make them more costly to make and repair, according to Ausra's executive vice president, John O'Donnell.
Ausra says its system can bring down the cost of solar power-generated electricity to be competitive with conventionally generated electricity. Ausra's Freshnel reflectors are flat, unlike the curved, finely tuned mirrors of the traditional trough design, according to the company. "It's a mindset that's much more like Toyota than like NASA," Mr. O'Donnell said. Ausra also directly heats water to generate steam, rather than first heating oil to generate heat. But the system is less efficient at converting solar energy to electricity than trough systems because it generates lower-temperature steam, Mr. O'Donnell said.
Ausra was originally founded in 2002 as Solar Heat and Power in Australia by David Mills, who originated the technology in the early 1990s at Sydney University, and Graham Morrison, who helped him develop it from 1995 to 2001. Solar Heat and Power built a one-megawatt pilot project in Australia for Macquarie Generation in New South Wales in 2004. The company, which changed its name to Ausra and moved to the United States in February, is also working on a second 38-megawatt capacity power plant it expects to have finished by 2009.
The company plans to build a 180-megawatt power plant at an undisclosed United States location, and is beginning construction on a 6.5-megawatt plant in Portugal, according to Messrs. Le Lièvre and O'Donnell. The company also plans to open offices in California, Colorado, and Arizona and to double its staff to 100 by the end of the year, they said.
After Gutenberg also has some comments on Ausra, noting the system is still dependent on water availability - though this is purely for turning turbines rather than cooling as in many coal and nuclear plants, so presumably this could be a nearly closed loop system (more at San Jose Mercury, Clean Break and The Energy Blog).
Ausra's core technology is the CLFR (Compact Linear Fresnel Reflector). Instead of the parabolic troughs or mirrors used in other solar thermal systems, this form of CSP (Concentrating Solar Power) uses flat reflectors moving on a single axis plus Fresnel lens to concentrate the solar thermal energy in collectors. Flat mirrors are much cheaper to produce than parabolic ones. Another advantage of CLFR is that it allows for a greater density of reflectors in the array. David Mills originally conceived of the approach in the early 1990s while at Sydney University.
Currently, Ausra is building a 30 MW solar thermal electric power plant, and in the process of scaling up to 2,000 MW over the next three years — enough power for two million homes in the United States. Founded by Dr. David Mills (who has spent the past three decades in Australia), Ausra got its big break last summer; Mills got to meet solar thermal advocate and venture capitalist, Vinod Khosla. "It's a great story, really," observers Toronto Star reporter, Tyler Hamilton1. "After years of trying to attract serious interest in his technology in Australia, Mills says he was getting ready to throw in the towel and retire." ...
"Worldwide, the electric power industry creates 40 percent of total carbon emissions, and electricity use is rapidly growing. Ausra's technology serves a critical need for utilities seeking large-scale affordable sources of clean power to meet the dual challenges of economic growth and carbon constraints," said Vinod Khosla, founder of Khosla Ventures and Ausra investor and board member.
One solar thermal electric power plant, the 354 MW SEGS (Solar Energy Generating Systems), which covers 1000 acres in the Mojave Desert in Southern California, produces 90% of the world's commercially produced solar power. One might perceive such a major effort as an impetus for new investors to believe in the potential of solar thermal.Ausra aims to expedite the utility industry's transition to clean energy, helping utilities meet renewable portfolio standards while keeping rates low and the power on for consumers day and night. "Economic development around the world, coupled with recognition that carbon emissions must rapidly be eliminated, has created an enormous market opportunity for companies that can deliver solar power at large scale and at reasonable cost," says KPCB Partner and Ausra investor and board member Ray Lane.
Lane sees solar thermal electric power generation as a "main event in renewable energy". It may be, provided that potential water shortages are addressed. As with other steam turbine systems, solar thermal is susceptible to a shortage of water.
The press release did answer one question. I wondered why, since investors were willing to put $40 million into CSP, specifically the Ausra Compact Linear Fresnel Reflector, then had foregone the combined technology developed at MIT. "We had been working on a wide range of alternatives and kept finding that simpler, cheaper approaches outperformed higher-temperature, more sophisticated designs," says Ausra Chairman David Mills.
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