Saturday 19/9/2009 Page: 2
WHEN Lindsay Tanner says greenies are "obsessed" with solar energy, he's right. And it's obvious why.Clean coal is a myth. Nuclear has radioactive waste and security issues and (read Helen Caldicott) it's not as efficient as they say. It would also be impossible to commission a nuclear reactor in Australia within a decade - especially near anyone's backyard - and we haven't got a decade to lose.
Natural gas is a huge opportunity in the transition to renewables, offering quick emissions reductions compared with coal. Gas-fired power stations are a good companion to renewable energy supply, because they can be turned on quickly to make up any shortfall without a lengthy start-up. But gas worn t get us the emissions cuts we will need by 2050.
Wind power is intermittent and the best sites have been snaffled up. Another 7000 MWs-plus of wind generation capacity will be developed over the next decade as we strive to hit our 20% renewable energy target. That'll help. Of the other renewable energy sources, wave, tidal power and geothermal are promising but unproven in Australia. Solar technology has been around for decades, the resource is abundant and the costs are coming down.
How abundant? This month's National Geographic cover story on solar energy estimated that the amount of electricity that could be generated by solar photovoltaics (PV) and concentrating solar thermal (CSP) each year was roughly 40 times the world's present electricity use. (In round figures, 745,000 terawatt hours a year of solar energy is available, and the world generated 19,000 terawatt hours in 2006, mostly from fossil fuels).
But the promise of solar has been around so long people don't believe it any more. NG's reporter quoted from a magazine article published in America in 1953, titled Why Don't We Hare... Sun Power? That old piece included this: "Every hour the sun floods the earth with a deluge of thermal energy equal to 21 billion tons of coal."
Adelaide-based scientist Monica Oliphant is president of the International Solar Energy Society. She has been a staunch advocate for solar energy since the Arab conflict and oil shock in the early 1970s, when she heard Nobel-prize winning Australian virologist Sir Macfarlane Burnet on the radio.
"I remember the day I was in the kitchen, [he] was saying: 'If we had solar energy we wouldn't have to fight over oil.' For Oliphant, who worked for South Australian utility ETSA for 18 years, supporting solar became "a philosophical thing". "Now is different to back in the '50s. We just had so much coal, oil and gas. Solar could never compete against those because they were heavily subsidised."
But investment in renewable energy increased by 17% between 2007 and 2008 and, despite a dip earlier this year, is climbing again. As well as supporting the installation of solar photovoltaic panels, Oliphant says: "If we're going to have a low-carbon economy, we have to have large scale generators."
The best thing out of the last federal budget was the $1.6 billion "solar flagship" fund to develop two to four solar energy stations with an expected 1000 MWs of combined generation capacity. The funding is to be matched 3:1 by private and state partners.
Boston Consulting Group was commissioned to design the flagship programs tender criteria and has reported to the Government. The BCG report hasn't been released but indications are the announced funding may not be enough to start 1000 MWs worth of projects, and other submissions, including from the Victorian Government, have recommended winding back the size of the power stations to a less risky, more bankable scale.
Oliphant says the funding available under the solar flagships program "probably isn't enough". The projects will have to be staged, she believes. Over-promising creates the risk of under-delivering. "Some of the new technologies shouldn't go too fast. If they're brought on too fast, before they're proven, and then they fail, it gives solar a bad name."
Californian company eSolar, backed by a $US10 million ($A11.5 million) investment from Google.org, the charitable arm of Google, believes stations generating 1000 MWs could be built for an overall cost of $US3 billion - the kind of ballpark figure the Australian Government envisaged.
Taking a unique approach, eSolar focused on getting the costs down to allow rapid deployment at scale. Its "power tower" technology uses off-the-shelf steam turbines, located on the ground rather than up in the air, like rivals. The mirrors used are standard oblongs, flat and low to the ground to avoid wind loading. The supporting frames are cheap. The towers are based on standard towers for wind turbines. The design is modular: if you want 50 MWs you build one, and if you want 500 MWs you build 10 - side by side.
The real brilliance of eSolar is in the tracking software, which uses high-definition video cameras on each mirror to adjust orientation constantly, maximising energy pointed at the target pipes atop the tower containing water to generate steam. So far eSolar has built one five-MW power plant in the US and has signed power purchase agreements for another 429 MWs. Earlier this year it signed an agreement with Acme, an Indian developer, that will see one GW of its solar thermal developed there.
A privately held technology licensing company led by dotcom (and tech-wreck) entrepreneur Bill Gross, eSolar is talking to potential Australian partners, including utilities AGL and Origin Energy, about submitting a proposal for funding under the flagship program. Precise costings are confidential, but eSolar vice president Raed Sherif says: "In parts of the US we are now competitive with natural gas."
The relative cost of solar is tied up with government support and subsidies - on both the renewable and fossil fuels side. Sherif spoke to BusinessDay from Berlin, where the SolarPACES industry conference was held this week. He said the conference mood was "mixed" amid fears that the Spanish Government, which has fostered a boom in solar energy, would withdraw support.
"If you look at the number of installations today, CSP or PV, is a good industry to be in. But it is true that this industry is not yet at a price level where it can compete with fossil fuels. It needs government subsidies, and these are sometimes not clear, and sometimes have been interrupted over the years."
paddy.manning@fairfaxmedia.com.au
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