This is part of IEEE Spectrum's ongoing coverage of Japan's earthquake and nuclear emergency. For more details on how Fukushima Dai-1's nuclear reactors work and what has gone wrong so far, see our explainer and our timeline.
Each of the major reactor accidents has had a major negative impact on global nuclear prospects, and Fukushima will be no exception.
The most immediate effect was in Germany, which immediately shut down its older reactors and put the rest under review. For a decade, Chancellor Angela Merkel has been trying to negotiate an "exit from the nuclear exit"--the plan adopted by a socialist-green government in the 1990s to phase out reliance on atomic energy completely. But she appears now to have thrown in the towel. Even more importantly, though nuclear-dependent generators have been trying to fight the reactor shut-downs, the national association of electricity generators has parted ways from that effort and seems to be acknowledging that nuclear power is basically dead in Germany.
In the meantime, China has suspended approvals of new nuclear reactor projects, the United States has inaugurated a review of existing plants, and proposed plants in India have suddenly become much more controversial. All older plants are subject to suspicion, and naturally the same is true of any plant proposed for a coastal site on the Pacific or Indian oceans and any in an area susceptible to severe earthquakes. As a result, the number of nuclear plants shut down in the coming years is sure to exceed the number of new plants brought into operation.
But that's nothing new. According to a Worldwatch Report released last week, in the three years from 2008 to 2011, eleven plants were closed worldwide while nine new plants were finished. Worldwide, the share of electricity generated from renewable resources now exceeds the fraction obtained from nuclear reactors. "In 2010 . . . worldwide cumulative installed capacity of wind turbines (193 gigawatts), biomass and waste-to-energy plants (65 GW), and solar power (43 GW) reached 381 GW, outpacing the installed nuclear capacity of 375nGW prior to the Fukushima disaster," says Worldwatch.
All this does not mean, of course, that there's no future role whatsoever for nuclear energy. Growth in wind energy may run into limits as the most attractive sites are exhausted. Sharply increased reliance on natural gas already is raising questions about the integrity of water supplies; because of chronic leakage of methane from gas distribution systems, the climate benefits of switching from coal to gas may be overrated. Photovoltaic electricity still is far from competitive in grid-scale applications, and may never be. So, in many instances, as countries and regions seek to cut carbon emissions and replace high-carbon energy sources, reactors will still look like the best alternative in some instances.
This last week, interestingly, the Tennessee Valley Authority (TVA) almost simultaneously announced plans to shut down 18 coal generating plants in response to tighter environmental regulation and, because of Fukushima, to upgrade infrastructure at six nuclear power plants.