The NRC license "creates a standard of performance there, and Southern Company expects to exceed it," Fanning said.
Allison Fisher, an energy expert for the consumer advocacy group Public Citizen, called the NRC's action — less than a year after the Japan crisis — a step in the wrong direction.
"It is inexplicable that we've chosen this moment in history to expand the use of a failed and dangerous technology," she said.
While other countries such as Germany are reversing their commitment to nuclear power, "the U.S. is approving new reactors before the full suite of lessons from Japan has been learned and before new safety regulations that were recommended by a task force established after the meltdown crisis at Fukushima have been implemented," Fisher said.
The NRC approved a new reactor design for the Vogtle plant in December. Utility companies in Florida and the Carolinas also plan new reactors that use the same design by Westinghouse Electric Co.
Jack Spencer, a nuclear expert for the conservative Heritage Foundation, called approval of the Vogtle project "good news," but added: "I don't think this is the beginning of a full-scale renaissance" for the nuclear industry.
"Too many questions remain" about nuclear waste, government regulation and development of nuclear technology, Spencer said.
Associated Press writer Kate Brumback in Atlanta contributed to this story.
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