Small Modular Reactor Design Considerations

Abstract

With growing worries about climate change and greenhouse gas emissions, issues and risks associated with hydrocarbon supplies, many government agencies are working to push the development of licensing for Small Modular Reactors (SMRs). SMRs are part of a new generation of nuclear power plants being designed all over the world. The objective of these SMRs is to provide a flexible and cost-effective energy alternative. Small reactors are defined by the International Atomic Energy Agency as those with an electricity output of less than 300 MWe, although general opinion is that anything with an output of less than 500 MWe counts as a small reactor. Modular reactors are manufactured at a plant and brought to the site fully constructed. They allow for less on-site construction, increased containment efficiency, and heightened nuclear materials security. The NRC’s licensing process (NUREG-800) up to this point has focused mainly on large commercial reactors. The design and safety specifications, staffing requirements and licensing fees have all been geared toward reactors with an electrical output of more than 700MWe. Licensing for SMRs has been an ongoing discussion, with workshops in October 2009 and June 2010 about licensing difficulties, and a congressional hearing in May 2010. A discussion of these design and licensing aspects and relative importance as it pertains to the NuScale Small Modular Reactor design is provided.