It should be continuing to generate electricity steadily for another 20 years, but early in May the Kewaunee nuclear power station on the Western, Wisconsin shore of Lake Michigan will close down for good, with the loss of some 650 jobs. The reason will not be wear and tear or the safety issues that often afflict reactors or, for that matter, predictable environmentalist opposition. Instead, its nemesis is something new and unexpected – shale gas.Dominion Resources, which bought the 39-year-old plant back in 2005, has been investing heavily to upgrade it, with the result that its operating licence has been extended for 20 years, allowing it to continue in production until 2033. But all for nothing; the tumbling price of natural gas, brought about by fracking, has meant that the company cannot make it pay its way.“It’s a fantastic plant,” the CEO, Thomas F Farrell, told The Washington Post. “Unfortunately the economics just don’t work.” The cheapness of gas, and its impact on electricity prices, meant the reactor just could not compete.The story is much the same right across the country, in Florida’s self-styled “home of the manatee”, Crystal River on the Gulf coast. Again the local nuclear power plant has a licence to operate well into the future, but again it is due to close for good. It has been offline since 2009, in need of repair, and last month its owner – Duke Energy – decided that it would be more economic to build gas-fired power capacity to take its place.