The following is just a small excerpt of an interesting piece by Australia’s Climate Spectator on why Australia doesn’t need coal. It was shared with me by a reader awhile back. It offers a particularly well-noted summary of why we don’t need baseload power, and why it can even “get in the way” — I think more diversity is needed than just solar thermal and wind, but overall points on baseload power are good (and note that some U.S. utility company CEOs have made essentially the same points). Anyway, here’s the portion of that article to which I’m referring:
… Mills last year released the first version of his ground-breaking research that showed that the entire US grid could be powered by just wind and solar thermal, and he provided an update on that research at the Solar 2011 conference on Wednesday. Mills challenges the very concept of baseload power, the sort provided by coal and nuclear.
“People say we need baseload plans, but we don’t,” he says. Instead, grids can work perfectly well with a mixture of inflexible supply (wind that blows whenever it wants), and flexible supply (solar thermal with storage). Mills has yet to release the financial modelling for his scenario, but notes that wind is already cheaper than new-built coal in the US, and solar thermal with storage, and used as a peaking plant, will be competitive with peaking gas.
Mills did not factor in PV in his scenario, but it would have the same impact as wind. As wind and PV fills up the energy stack (they go first because they have the lowest short run marginal cost – wind and solar radiation is free), what is needed to complete the requirements is flexible generation. Coal doesn’t fit the bill.
The first impacts of this have already been seen in South Australia, where wind has provided more than 20 per cent of annual output last year and much higher on occasions. In Germany, where wind and PV capacity amounts to 45GW, Statkfraft has announced this week that it may close two gas-fired power stations, amounting to one gigawatt of capacity, because of this impact. And this in a country which has just shut down half its nuclear fleet and will soon close the rest.
A UNSW team of Ben Elliston, Mark Diesendorf and Iain MacGill has just released its own study of how Australia could power its entire grid on renewables. And like Mills, they also see solar with storage as a type of peaking plant. “The whole concept of baseload becomes redundant,” Elliston told Climate Spectator. “It’s worse than redundant, it gets in the way.”
Coal power plant via shutterstock
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