The U.S. Nuclear Regulatory Commission (NRC) on Sept. 16 issued design certification for GE Hitachi’s Economic Simplified Boiling Water Reactor (ESBWR), the company announced.
The ESBWR is a Gen-III+ advanced boiling water reactor (BWR) that employs true passive safety systems and a simplified design utilizing natural circulation. These attributes allow the reactor to cool itself for more than seven days without operator intervention or the need for on- or off-site power.
GE Hitachi said that based on core damage frequency, the industry standard measure of safety, the ESBWR is the world’s safest approved nuclear reactor design.
NRC design certification means that an application for a nuclear power plant license referencing a certified design need not submit safety information for that design. Instead, the license application and the NRC’s safety review would focus on site-specific safety issues for the proposed plant.
The ESBWR has a net rated power of 1,520 MWe and a 24-month fuel cycle. In the event of a shutdown and site power failure, the reactor employs isolation condensers, a gravity driven cooling system, and a passive containment cooling system to remove decay heat. The systems work automatically in concert to maintain core water levels.
The design is substantially simpler than earlier BWR models, requiring 25% fewer pumps, valves, and motors. The core is also shorter than earlier designs to reduce pressure drop over the fuel.
Though GE Hitachi has been developing the ESBWR for many years (the application for certification was filed in 2005), the risks of a station blackout to BWRs rose significantly in profile after the Fukushima Daiichi disaster in Japan in 2011. Safety systems in the BWRs at Fukushima Daiichi were unable to remove decay heat after the tsunami destroyed the plant’s backup diesel generators, resulting in substantial core damage.
Two NRC license applications that would employ ESBWR technology are currently pending. DTE Energy has proposed using the ESBWR for its Fermi 3 expansion; NRC license approval is expected in 2015. Meanwhile, Dominion Virginia Power selected the ESBWR for its North Anna Unit 3 Nuclear Power Plant project, with license issuance expected in 2016.
Overseas, the Nuclear Power Corporation of India Ltd. has selected a site in the Kovvada region in the state of Andhra Pradesh for the eventual construction of multiple ESBWRs. Other potential projects include sites in Finland, Poland, Saudi Arabia, Sweden, Vietnam, and others. NRC approval opens the door for the ESBWR to be built in other locations around the globe.
“Achieving design certification means the ESBWR, the world’s safest reactor, can now become a reality,” said Caroline Reda, president and CEO of GE Hitachi. “Design certification will not only benefit our U.S. customers, it marks a crucial step forward for the ESBWR’s commercial advancement globally.”
—Thomas W. Overton, JD is a POWER associate editor.