Scientific American: A Solar Grand Plan

New scientific findings from Ausra show solar can affordably power our cars, homes, factories and economy

PALO ALTO, Calif.—March 6, 2008—Ausra Inc., the developer of utility-scale solar thermal power technology, has published a peer-reviewed study showing that over 90 percent of the U.S. electric grid and auto fleet's energy needs could be met by solar thermal power.

Solar power is the nation's largest primary renewable energy resource, offering many times total U.S. energy needs. Solar thermal power stations use fields of mirrors to capture the sun's energy as heat to boil water and drive steam turbines. Solar thermal's low-cost, efficient heat storage makes solar thermal power uniquely able to provide a reliable energy supply from ever-varying sunshine.

The Department of Energy's Energy Information Administration projects over 70 percent total growth in the nation's electricity demands by 2025, and analysts predict a further increase in electricity needs as plug-in electric hybrid vehicles come to the market.

"The U.S. could nearly eliminate our dependence on coal, oil and gas for electricity and transportation, drastically slashing global warming pollution without increasing costs for energy," said David Mills, chief scientific officer and founder at Ausra. "This new study shows that our daily and annual energy needs closely match the energy production potential from solar thermal power plants with heat energy storage, and our models show solar thermal power will cost less than continuing to import oil."

Mills is the inventor of the absorber surfaces used in the majority of the world's solar hot water heaters and the pioneer of Ausra's compact linear Fresnel (CLFR) technology. He presented his findings yesterday at the IEA SolarPACES solar research conference in Las Vegas (http://solarpaces.org). He co-authored the new paper with Robert Morgan, Ausra's chief development officer. A copy of the complete findings can be found at http://ausra.com/technology/reports.html.

Converting the national electricity grid to solar thermal power would reduce overall American global warming pollution by 40 percent. The combination of plug-in hybrids and solar thermal power would eliminate the importation of 13 million barrels of fuel per day. The study finds that because the seasonal and daily patterns of solar radiation already correlate strongly with electricity use, just 16 hours of thermal storage can provide reliable, load-following electric power.

"Near-zero pollution technology has to replace most of our current electricity generation by mid-century to prevent the worst global warming outcomes," said Stephen Schneider of Stanford University, who was a principal author of the 2007 Intergovernmental Panel on Climate Change Synthesis Report. "We've got to cut pollution 80 percent by mid-century, and that means transforming both our electric power and transportation sectors."

Solar thermal power complements other technologies such as wind, solar photovoltaic and geothermal generation. "Historically, our country has moved rapidly to build generation to meet market opportunities and grid needs," said Robert E. Fishman, Ausra's chief executive officer. "Between 1996 and 2005, the decade of gas, we built over 250 gigawatts of natural gas-fired power plants, a quarter of total U.S. generating capacity. As the solar thermal power industry moves to scale now, we are entering the decade of solar and building a reliable, affordable source of power to meet both the needs of our growing economy and the challenge of eliminating pollution."

About Ausra Ausra Inc. develops and deploys utility-scale solar thermal power technology to serve global electricity needs in a dependable, market competitive, environmentally responsible manner. Located in Palo Alto, Calif., Ausra is a privately held company funded by Khosla Ventures and Kleiner, Perkins, Caufield & Byers. To learn more about Ausra and solar thermal power in general, visit www.ausra.com.