The Nuclear Regulatory Commission (NRC) has approved a nuclear reactor designed by Westinghouse Electric Co. that could power the first nuclear plants built from scratch in the U.S. in more than three decades.
The U.S. government regulators unanimously approved the AP1000 reactor on Thursday. The certification, effective immediately, will be valid for 15 years.
NRC Chairman Gregory Jaczko said the newly approved design would ensure safety through simplified, passive security functions and other features. He said plants using the design could withstand damage from an airplane crash without significant release of radioactive materials - an issue that gained attention after the 2001 terrorist attacks.
Approval of the design is a major step forward for utility companies in four southern states that have billions of dollars riding on plans to build AP1000 reactors in the Southeast. Without NRC approval, the utilities could not have obtained a license to build their plants.
Federal officials approved an earlier version of the AP1000 reactor in 2006, but it was never built in the United States. Four AP1000 reactors are now under construction in China.
Aris Candris, Westinghouse president and chief executive, said the road to receiving design certification of the AP1000 "has been long and sometimes arduous."
The NRC vote brings the U.S "one step closer to constructing AP1000 units and putting thousands to work to ultimately provide future generations with safe, clean and reliable electricity," he said.
The biggest difference between the AP1000 and existing reactors is its safety systems, including a massive water tank on top of its cylindrical concrete-and-steel shielding building. In case of an accident, water would flow down and cool the steel container that holds critical parts of the reactor - including its hot, radioactive nuclear fuel.
An NRC taskforce examining the nuclear crisis in Japan said licensing for the AP1000 should go forward because it would be better equipped to deal with a prolonged loss of power - the problem that doomed the Fukushima Dai-ichi plant.
Marilyn Kray, president of NuStart Energy Development, a nuclear industry consortium that has worked to demonstrate the design's effectiveness, said she was pleased to see the design move forward.
"The AP1000 is the reactor design that will set the foundation for the next generation of nuclear plants in the U.S.," Kray said.
A nuclear watchdog group called the vote disappointing, saying the NRC should have done a new analysis in the wake of the Japan crisis, which occurred after a March 11 tsunami sent three reactors at the Fukushima Dai-ichi plant into meltdowns in the worst nuclear crisis since Chernobyl in 1986.
A new study could have helped identify and correct any vulnerabilities based on lessons learned from Fukushima, said Edwin Lyman, a senior scientist at the Union of Concerned Scientists.
"It would be more efficient and cost-effective to address problems that could be corrected at the design stage now, before any new plants are constructed," Lyman said.
After plants are built, any new safety requirements would have to be addressed through costly retrofits and other actions, Lyman said, adding that he was "far from convinced" that the AP1000's passive safety features would be effective in coping with severe accidents.