OBSTACLES TO OVERCOME BY SMALL MODULAR REACTORS (SMRs)

摘要

The development of and support for small modular nuclear power plants (NPPs) is gaining strong momentum in USA. The reasons are that they could require reduced financing and shortened construction schedule. Also, they could address the reduced size need for electricity in some USA locations and, in particular, in developing foreign countries. However, the prevailing enthusiasm needs to be moderated until several potential obstacles are overcome. There are three principal USA obstacles: (1) the successful licensing and certification of the SMRs by the Nuclear Regulatory Commission (NRC) to confirm their safety; (2) SMRs ability to demonstrate that they can compete financially against less costly modular natural gas power plants or the limited purchase of electricity from new large light water reactors (LWRs); and (3) the need to work into the prevailing fuel cycle while not deteriorating spent fuel disposal or increasing proliferation. Clearly, Babcock& Wilcox's and Nu Scale Power's SMRs have the earliest chance for success because they would rely upon the present LWR regulatory and fuel cycle experience. Their main obstacle will be demonstrated costs from prototype plants and the willingness to accept fixed turnkey contracts for additional units. The more visionary SMRs such as GE-Hitachi PRISM or the Hyperion Power Generation smaller liquid metal closed fuel cycle reactors will have to overcome more difficult and lengthy regulatory assessments. Also, a complete fuel cycle infrastructure will need to be developed. Penetration of developing foreign countries will be the most difficult because it will demand the development and establishment of a nuclear safety infrastructure in those countries. The International Atomic Energy Agency (IAEA NG-G-31) has detailed the numerous actions and large time schedule and efforts to achieve an adequate safety culture. Also, several export licenses and monetary loans will be required. Furthermore, it will be necessary to overcome the lack of insurance for severe accidents and the anticipated USA refusal to accept domestic disposal of foreign High Level Waste (HLW). This means that government owned suppliers such as Russia have definite advantages over the USA private suppliers because of their willingness to provide loans and handling HLW. This paper first summarizes the power history growth of USA reactors and the recent momentum developed for USA SMRs; it is followed by available brief descriptions of USA LWR SMRs and some of their potential obstacles; more advanced USA SMRs designs and their potential difficulties come next; foreign applications are covered last and they are followed by a Conclusions section.