Energy solution is glaring at us

Courier Mail
Wednesday 25/7/2007 Page: 28

THE state which taught the world how to dig up coal faster than anyone else could be powered almost entirely by discarded sugar cane, radioactive rocks and the sun, a thought-provoking book claims. Greenhouse Solutions, launched earlier this month by alternative energy guru Mark Diesendorf, paints a radically different future for Queensland where it truly lives up to its moniker "the Sunshine State".

"Seven per cent of households in Queensland have solar hot-water heaters. That's astonishingly low," the University of New South Wales Institute of Environmental Studies expert said. "Potentially three-quarters of households could be fitted with them, which would substitute for one large coal-power station. "Commercial buildings could take a large amount, such as schools and hospitals and other low-rise buildings, and a lot of industrial heat is needed at the low temperatures generated by solar hot water such as in food processing."

While hot-water heater technology is already here, Dr Diesendorf said few people realised large-scale solar thermal power plant technology was also already in existence. "A large-scale demonstration plant was built in California 20 years ago and it's still going," he said. "The great advantage of this technology over photo-voltaics (solar panels) is it's fairly cheap to store heat in water, rocks or thermo-chemicals overnight, so you can generate 24 hours a day. In 10 to 12 years prices will come down to where wind energy is at today.

"It depends a lot on government, but I think beyond 2014 we will start to see large solar power stations in Australia, while there will be no clean-coal plants or nuclear-power stations significantly before 2020." Crop waste, particularly bagasse from sugar cane, was also likely to play a bigger role in coming decades. "There's a good 1600MWh (megawatt hours) of power in that. This is not negligible stuff, its the equivalent to two Kogan Creek-sized coal-power stations," Dr Diesendorf said. "It still needs a driver from government.

These power stations will be smaller because you can't afford to transport crop waste too far, so the power will probably be in the order of 10t a kWh (more than twice brown coal)." He predicted the first 1000MW geothermal power station would probably be on line by 2014, most likely in South Australia where the Olympic Dam uranium mine was tipped to be the first customer.

He said geothermal power from radioactive hot rocks buried kilometres underground in outback Australia was a serious source of baseload power, particularly for central Queensland, and could generate electricity for as little as 6C a kWh. Even wind had a future in Queensland, although the greatest potential was in southern states where winds were strongest. Experience in Denmark showed it could generate 20 per cent of its needs from wind without major problems on calm days. "South Australia has trouble at the moment only because all its wind farms are coastal and point in the same direction and they don't have enough interstate connections to share power when the wind isn't blowing," he said. "Large-scale wind farms spread over a large area tend to smooth out fluctuations."