With green power comes great responsibility - It's time politicians listened to scientists on wind and solar energy.

Age
Saturday 10/10/2009 Page: 5

CLIMATE change is a diabolic problem, but the brightest minds are working fiendishly to find genuine solutions, and they will carry the day. One such is David Mills, one of our most successful scientists, formerly from the Sydney University who quit Australia a decade ago to launch solar energy company Ausra in California. It was one of our best brain-drain moments. Dr Mills is participating in a US study that will soon put paid to that old chestnut- let's quote Malcolm Turnbull from 2007, but it could have been any mainstream Australian politician today - "you cannot run a modern economy on wind farms and solar panels".

In a project funded byAl Gore's Alliance for Climate Protection, America's energy utilities gave researchers at Stanford University a data dump of all the electricity used across the country in 2006 - hour by hour-to get a full picture of the load that year. The scientists then calculated whether that demand could have been met using the available wind and solar energy. Without preempting the results, which will be released next month, Dr Mills this week gave a pretty clear indication- yes, it can.

"We are finding that solar and wind are a beautiful match for each other and together can carry almost the entire electrical load of a large economy," he said in a Deakin lecture in Melbourne on Tuesday. A key factor is connectivity of the power grid. With thousands of wind turbines installed across the country, for example, the wind will generally be blowing somewhere. Dr Mills says if interconnected wind is used on a large scale, a third or more of its energy can be used as reliable electric power. A key factor is energy storage, the hottest area of research with about 20 programs under way worldwide. The storage can allow solar thermal power stations to run into the night.

In a separate study two years ago, Dr Mills found that 93% of California's annual grid electricity could be supplied by solar thermal power stations with just 15 hours storage. solar thermal stations with storage could supply 95% of the US annual grid, using land of 140 kilometres square. OK, you ask, but how much does this interconnected wind and solar grid cost? Well, costs haven't been factored into the Stanford study. But Dr Mills won't enter the game of swapping cents-per-kW-hour forecasts for plants installed in future years based on theoretical cost curves and as-yet-unknown technological developments.

The comparisons are false anyway. Coal has all its development and infrastructure funding built in, and is taking a terrible toll on the planet. The nuclear industry, Dr Mills says, is highly secretive about its true generation costs, and it got huge subsidies and public investment during the Cold War. Anyway, the cost of renewable energy solutions is dropping quickly as competition intensifies; further, the cost of inaction is going up as governments squabble and climate change accelerates.

For example, among rival bidders for solar thermal development contracts including Australia's $1.5 billion Solar Flagships program (which aims to part-fund development of 1000 MWs of solar generation capacity) - Dr Mills says costs are going "through the floor". Dr Mills says Ausra has the cheapest solar thermal technology in the market. But recently the 850-MW Calico (Solar One) project in California, being developed by Tessera Solar and Stirling energy Systems, was costed at $US2.2 billion ($A2.4 billion).

That costing, he says, is aggressive and will be challenging for older technology. "It will drop the price bar of solar again if it's true," he says. It's exciting, and Dr Mills has no doubt wind and solar can power Australia as well, even though we have a smaller population (concentrated on the coast, where cloud increases) and fewer generators and wind speeds here are lower than in the US. "I believe this will bias Australia toward a larger fraction of storage solar and a smaller fraction of uncontrollable wind," he says. "It is becoming clear that [concentrating solar thermal] with storage is the logical future of electrical generation for Australia."

Dr Mills says concentrating solar thermal is going through a flowering of design and form, as did the development of cars and aircraft. The project pipeline is substantial. While only 600 MWs of solar thermal power is up and running worldwide, another 400 MWs is under construction and there are 14,000 MWs of "serious" concentrating solar thermal (CST) projects being developed. He says the solar thermal market as a whole is set for takeoff in 2015, but after a round of meetings he worries Australian politicians and executives are not up to speed on the progress being made in this field overseas. His observation includes representatives of our energy companies, who Dr Mills says "should know".

Compare Dr Mills' intelligence and vision for the future with that of two key figures in our climate change debate: federal Energy and Resources Minister Martin Ferguson and his Opposition counterpart (and Howard government predecessor) Ian MacFarlane (for his form, check Wikipedia). Whatever these two nowadays-closet sceptics negotiate for an emissions trading scheme, it won't work: it will try to prop up the industries of the past and it won't last, because a worsening climate crisis will quickly overtake it.

paddy.manning@fairfaxmedia.com.au