Believe it and we can do it

Age
Saturday 27/2/2010 Page: 2

LAST October, after an interview with Australian solar pioneer David Mills, this column previewed a Stanford University study showing that renewable sources - principally wind and solar - could meet all of our energy needs.

The co-author of that study, Mark Jacobson, Stanford professor of civil and environmental engineering and director of the university's atmosphere and energy program, appeared by videoconference at last weekend's Sustainable Living Festival in Melbourne. He spoke to the findings of his study, which was the cover story in November's Scientific American magazine and has generated plenty of debate in the US (and some here too).

Jacobson and Mark Delucchi, a research scientist at the University of California, compared available world renewable energy resources - wind, water, sunshine - with maximum forecast energy demand, including transport, of about 16.9 terawatts (1 terawatt e(equals a trillion watts) in 2030 - up from 12.5 terawatts now. Eliminating fossil fuel and biomass combustion would reduce overall demand to 11.5 terawatts, the study found, because electric power is more efficient.

Could this prodigious amount of energy be met by available renewable resources? Yes, with a massive building program. The world would need 3.8 million 5MW wind turbines to provide 51% of supply. We would need 49,000 large-scale 300MW concentrating solar energy stations, plus 40,000 large-scale 300MW solar photovoltaic power stations, plus 1.7 billion 3kW domestic-scale rooftop PV systems, to provide another 40% of supply. Less than 1% of this wind and solar energy infrastructure is in place already. The remaining 9% of the world's power supply would come from 900 hydro-electric power stations (mostly built); 5350 geothermal plants, each generating 100MW (mostly not built); and thousands and thousands of small tidal power and wave installations.

Given they are intermittent power sources, can wind, wave and solar meet demand as it arises? Yes. First, renewable energy power plants generally suffer less down time. Second, with extensive interconnection between geographically dispersed sources, a lack of wind or sunshine in one place can be substituted by power from another.

As Jacobson and Delucchi wrote in their magazine article: "Because the wind often blows during stormy conditions when the sun does not shine and the sun often shines on calm days with little wind, combining wind and solar can go a long way toward meeting demand, especially when geothermal provides a steady base and hydroelectric can be called on to fill in the gaps." Third, a smart grid allows demand to be shifted into off peak periods - so electric cars are charged overnight while demand is lower, for example. The cost? The scientists estimated the overall construction cost would be in the order of $US100 trillion over 20 years, not including transmission.

Professor Jacobson told me transmission would add about 10% to the total cost. He says power lines last over two or three generations of power plants and are a relatively smaller part of the upfront cost per kWh generated. That's the bill for a whole new, clean and efficient energy system and (if we move quickly) massively reduced bills for climate adaptation. The bill would be recouped by charging a forecast US4¢-US10¢ per kWh, competitive with existing fossil fuel and nuclear sources, which average US7¢/kWh in the US, and rising.

Last Sunday, Jacobson dismissed the nuclear alternative. Based on a full lifecycle analysis, nuclear is not clean, producing nine to 17 tines the carbon dioxide equivalent per kWh generated by wind energy. Nuclear is getting more expensive, not cheaper, unlike wind and solar. It seems a rapid transition to 100% renewable energy is not only possible, it may be cost-competitive with the touted "clean coal" and nuclear alternatives. In our national and state capitals, and probably in our boardrooms, it would be dismissed as a pipe dream. In the real world - the planet we live on - it will soon enough become a necessity.

Relative to the rest of the world, Jacobson describes Australia's clean energy resources as "amazing". Appearing alongside Jacobson last weekend were Philip Sutton, co-author of Climate Code Red, and Matthew Wright, executive director of Beyond Zero Emissions. Both are working on plans to switch Australia over to renewable energy. BZE's recently released "Transition Decade" (or T10) plan estimates a complete switch by 2020 would cost $40 billion a year or 3-3.5% of GDP.

The linchpin of BZE's plan is to build a dozen concentrating solar thermal sites around Australia, each generating 4000mw, to provide 60% of our power needs. The technology to generate solar energy, with up to 16 hours of storage so it can run overnight, exists now and is being used in Spain. Wind power would provide the remaining 40%. Wright told the audience that T10 - a plan, not the only plan - was meant to rebut the "can't do mantra" of the fossil fuel lobby: renewable energy cannot supply baseload power, is too expensive, will wreck the economy, and will cost jobs. What rubbish. Wright has a "can do" mantra, and it's what we need.

paddy.manning@fairIaxmedia.com.au