Design shortcomings in the reactor the U.S.' biggest nuclear supplier, Westinghouse Electric, intends to sell to India are likely to delay the conclusion of a commercial agreement by at least a year.
The U.S. Nuclear Regulatory Commission (NRC) is examining the modified reactor design submitted by Westinghouse after an assessment in October last. The NRC was not convinced that three aspects of the design shield would withstand earthquakes and tsunamis of a certain magnitude. It has held several public and closed-door meetings on the design changes to be introduced in the shield building (SB) of the AP1000 reactor.
Asked about the impact of the NRC's findings on the Nuclear Power Corporation of India Limited's (NPCIL) negotiations with Westinghouse, a senior government official said these were at a very preliminary stage. “In any case, commercial discussions have been stymied by the Part 810 issue,” the official said referring to a certification requirement that the U.S. sprung on India last year. After some deliberation, the NPCIL provided the necessary letter but Washington has not yet reverted to India.
“We are aware of the issue of safety concerns in the AP1000 reactors. These are not insurmountable but they will have to be addressed before they are brought to India,” the official said.
The Hindu contacted Westinghouse on e-mail and a response is awaited. On its website, Westinghouse acknowledged that the NRC issued a letter on October 15, raising issues regarding the AP1000's steel concrete composite, reinforced concrete construction and tension girder.
Enhancing safety
The company said it was addressing the NRC's comments about SB in an “integrated and complete fashion.” The design changes to enhance the safety of the structure are under way and will be described in the submittal to the NRC in early 2010. Westinghouse will demonstrate that the AP1000 SB design is safe and robust with ample safety margin to meet the NRC general design criteria and regulatory requirements through analysis, benchmarking and testing, it added.
“The company has given a basic description of the changes [on March 22]. We are waiting for an in-depth analysis. We have not reached any final decision. Once we have conducted an in-depth analysis we'll be able to set a firm schedule for completing the approval process,” NRC spokesman Scott Burnell told The Hindu over telephone from Washington while indicating that the examination could extend up to 2011.
India had promised to place orders for 10,000-MWe reactors from U.S.-origin companies in the run-up to the nuclear deal.
Mr. Burnell said the NRC's mandate was limited to reactors to be installed in the U.S. It was up to the country that imported the reactor to decide whether it wished to make an independent assessment or rely on the NRC's findings. “If some country asks the NRC about the safety concerns of a reactor we will provide that. It depends from country to country whether they want our approval or not.”
Asked whether the NRC had entered into a formal communication with the NPCIL regarding this, the spokesperson said he was not aware of any specific discussions with India regarding the design aspect of the safety shield.
“The U.S. and India have a formal agreement on nuclear technology. The NRC is closely working with its Indian counterparts.”
