Nukes suck for load following, France sells electricity at a loss off-peak and imports expensive peak-load electricity.
And when it gets hot, they have to shut the nukes down - something which has been happening more frequently,
with serious problems in 2003, 2006, and 2009:
http://business.timesonline.co.uk/tol/business/industry_sectors/utilities/article6626811.eceJuly 3, 2009
France imports UK electricity as plants shut
Robin Pagnamenta, Energy and Environment Editor
France is being forced to import electricity from Britain to cope with a summer heatwave that has helped to put a third of its nuclear power stations out of action.
With temperatures across much of France surging above 30C this week, EDF’s reactors are generating the lowest level of electricity in six years, forcing the state-owned utility to turn to Britain for additional capacity.
Fourteen of France’s 19 nuclear power stations are located inland and use river water rather than seawater for cooling. When water temperatures rise, EDF is forced to shut down the reactors to prevent their casings from exceeding 50C.
A spokesman for National Grid said that electricity flows from Britain to France during the peak demand yesterday morning were as high as 1,000MW — roughly equivalent to the output of Dungeness nuclear power station on the Kent coast.
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In 2003, the situation grew so severe that the French nuclear safety regulator granted special exemptions to three plants, allowing them temporarily to discharge water into rivers at temperatures as high as 30C. France has five plants located by the sea and EDF tries to avoid carrying out any repairs to them during the summer because they do not suffer from cooling problems.
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http://ipsnews.net/news.asp?idnews=34121ENVIRONMENT: Heat Wave Shows Limits of Nuclear Energy
By Julio Godoy
PARIS, Jul 27, 2006 (IPS) - The extreme hot summer in Europe is restricting nuclear energy generation and showing up the limits of nuclear power, leading environmental activists and scientists say.
The heat wave since mid-June has led authorities in France, Germany, Spain and elsewhere in Europe to override their own environmental norms on the maximum temperature of water drained from the plants' cooling systems.
The French government announced Jul. 24 that nuclear power plants situated along rivers will be allowed to drain hot water into rivers at higher temperature. The measure is intended "to guarantee the provision of electricity for the country," according to an official note.
France has 58 nuclear power plants, which produce almost 80 percent of electricity generated in the country. Of these, 37 are situated near rivers, and use them as outlet for water from their cooling systems.
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