Nuclear reactors can't take the heat
France's soaring temperatures have forced the heavily nuclear-dependent country to take the unusual step of importing electricity, as nuclear reactors slowed down in the summer heat.Many of France's 44 riverside reactors were banned from releasing cooling waters into rivers to protect flora and fauna, already affected by low water levels and high temperatures.
Electricity production slowed and some reactors shut down altogether, while the increased use of ventilation and air conditioning drove up demand by 3%.
With 80% of France's electricity coming from its 58 nuclear reactors, the heat wave put significant pressure on the grid. Increased activity at reactors near the sea helped ease the crisis.
But French company EDF still had to import 2,000 megawatts from Switzerland and Italy. This is despite the government authorising the operators of several reactors to release water warmer than the usual limit.
EDF assures that the discharge of cooling waters does not affect wildlife, quoting scientific evidence from the last time a similar situation occurred in 2003.
Environmentalists question these results, and blame the need for imports on France's "energy unilateralism".
Greenpeace said that the over-reliance on nuclear is both harmful and unwanted, quoting a recent public survey which found only a third of the French want further development of nuclear in response to the energy crisis. This compares with 84% who favoured renewables.
Nuclear reactors' poor performance in the heat also provides a counter-argument to their promotion as part of the global warming solution.
In Britain, the heat wave also affected electricity demand as air conditioning went into overdrive, leading to last week's blackouts in central London.