Solar thermal energy can `replace coal in US'

Canberra Times
Monday 21/4/2008 Page: 3

Solar thermal electricity can be the "big gorilla on the grid", replacing coal-fired power stations across the United States - the world's biggest greenhouse polluter - over the next 40 years, a leading Australian scientist says. California-based solar energy entrepreneur and former Sydney University physicist David Mills told a US energy conference solar power was the only technology capable of ''almost eliminating" global warming caused by electricity generation by 2050.

Solar thermal electricity could supply "the great majority" of the US electricity grid and " by logical extension those of China and India", as well as eliminating carbon emissions from cars by powering fast-recharging electric vehicles. Earlier this month, federal Energy Minister Martin Ferguson described Australia as a fossil fuel dependent economy, adding there was no alternative to building new coal-fired power stations.

Frustrated by a lack of federal funding for renewables, Dr Mills left Australia last year to base his solar energy company, Attsra, in California, after venture capitalists offered $ U S40 million ($A43 million) to bankroll his world-first technology. The company is currently building a 177-megawatt solar thermal plant to supply the Pacific Gas and Electric Company, with California Governor Arnold Schwarzenegger launching the project last November.

Addressing an International Energy Agency conference in California, Dr Mills said peer-reviewed research showed 90 per cent of US electric grid and car energy needs could be met by solar thermal power. "The US could nearly eliminate dependence on coal, oil and gas for electricity and transportation, drastically slashing global warming pollution without increasing costs for energy.

This new study shows that our daily and annual energy needs closely snatch 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." Dr Mills called for " a rethink of the function and forth of electricity grid networks" to include solar thermal arrays, which use lines of computer controlled mirrors to capture the still's energy to boil water and drive steam turbines.

During a visit to Australia this month, Dr Mills said China "clearly favours solar thermal far above airy other resource" for electricity generation and had already held high-level discussions with his company. CSIRO National Solar Energy Centre research leader Wes Stein said solar thermal energy could make a "substantial and positive" contribution to cutting Australia's greenhouse emissions.

"The technology is certainly there and we can do it, but there are complexities and a lot of pragmatics to consider because it takes time for large solar installations to be designed and built." It would only require a solar thermal array built across an area about "50km by 50km square in the centre of Australia somewhere" to supply all of Australia's electricity needs by 2020, he said. "solar thermal is really taking off globally and there is an opportunity for Australia to get on board as a maker, rather than a taker, of technology."