It is a criticism frequently leveled at those promoting wind or solar power as an alternative to fossil fuels: what happens when the wind doesn't blow or the sun doesn't shine?
Well, now there is a smart answer, at least in Europe -- we'll simply and instantly switch to another source of clean, green power.
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The gird should mean that when one source falls short, another takes up the slack to ensure continuity of supply.... It is seen as an essential step towards the European Union's pledge to source 20 percent of its electricity from renewables by 2020.
Kirt

