Nuclear reactors that are about a third the size of those now used by power companies may have a safety edge over larger units after Japan’s reactor crisis, the U.S. Energy Department said.
The small modular reactors proposed by some manufacturers have a “lower power level” and “require less cooling after shutdown,” John Kelly, a deputy assistant energy secretary, said today at a hearing of the Senate Energy and Natural Resources Committee. They can be built underground “which should improve their security profile and may enhance their seismic safety,” Kelly said.
The Senate panel is discussing legislation that would help companies build a new generation of nuclear power plants. A bill from the committee’s chairman, Senator Jeff Bingaman, a New Mexico Democrat, would direct the Energy Department to help win regulatory approval for small-reactor designs by 2021.
Bingaman introduced his measure three days before a 9-magnitude earthquake and tsunami on March 11 crippled Tokyo Electric Power Co.’s Fukushima Dai-Ichi plant with fires, explosions and radiation leaks in the worst nuclear incident since the 1986 Chernobyl disaster. The crisis in Japan has put U.S. reactors under scrutiny by lawmakers and regulators.
Smaller reactors could be built in retooled U.S. factories and sold to domestic and international customers, according to the Commerce Department. While most existing reactors can generate from 800 megawatts to 1,200 megawatts of electricity, the smaller plants would be 300 megawatts or less, according to the department.
The plants would be similar to the reactors used in the U.S. Navy’s submarines and ships, Joe Colvin, president of the La Grange Park, Illinois-based American Nuclear Society, said at the hearing.
New reactor designs are being developed by companies such as Westinghouse Electric Co., a unit of Tokyo-based Toshiba Corp., and Babcock & Wilcox Co. of Charlotte, North Carolina.
President Barack Obama wants Congress to approve $67 million in fiscal 2012 for the Energy Department to start helping small-reactor developers. Obama’s proposed program is similar to the concepts outlined in Bingaman’s bill.
The cost of building a conventional two-reactor nuclear plant exceeds $14 billion, Bingaman said. Smaller-scale reactors “hold the promise of reducing the cost of nuclear-plant construction,” he said.
Smaller plants may give the nuclear industry opportunities for expansion, Senator Lisa Murkowski, an Alaska Republican, said at the hearing.
“Not every utility or operating site needs, or even can handle, a thousand-plus megawatts of nuclear capacity,” said Murkowski, a co-sponsor of Bingaman’s bill.
The Nuclear Regulatory Commission, which will decide whether small atomic-power plants can be built in the U.S., started a 90-day safety review of the nation’s existing 104 commercial reactors after the Japanese disaster. The agency’s post-Fukushima task force is due to release the results of the review next month, according to the NRC.
Backers of small reactors want the NRC to issue rules that are weaker than the regulations for larger plants, Edwin Lyman, a nuclear specialist with the Union of Concerned Scientists in Cambridge, Massachusetts, said at today’s hearing.
If smaller plants get breaks on “emergency planning, control room staffing and security staffing,” then they “will not necessarily be safer than large reactors,” Lyman said.
Bingaman’s bill is S. 512.