Impact of Testing Activities on Small Modular Reactor Total Capital Investment Cost

Abstract

The use Total Capital Investment Cost (TCIC) as a figure of merit to evaluate the design of a Nuclear Power Plant can help lead to more economically competitive designs. TCIC includes costs of equipment, labor, materials and the associated time value of capital. The team developed the software tool EVAL, which is capable of determining TCIC impacts for any nuclear island (NI) of any design. EVAL was first used to estimate the effect of modularization on TCIC in constructing the Westinghouse Small Modular Reactor (SMR). In particular, three different construction cases were identified. In the first case, modules are manufactured in the fabrication facility and assembled into Super Modules (SMs) in the on-site assembly area, while SMs are assembled in the hole to form the NI. The second case differs from the first case in the fabrication process, as modules are manufactured in the on-site assembly area. In the third case, the NI is ‘stick built’; i.e., the modules are assembled in the hole, where all connections are performed and the structures are built. The analysis highlighted the positive impact of off-site modular construction on TCIC. EVAL is based on an open evaluation methodology. In this paper, we present an extension of EVAL that aims to analyze the impact of testing on TCIC. As only few Nuclear Power Plants (NPP) were built in the recent years, testing costs and durations are characterized by a high uncertainty. EVAL was used to evaluate the impact of testing on TCIC, considering a range of realistic data points. Testing costs were expressed as a percentage of total labor costs and TCICs were calculated for the three construction strategies. EVAL was also used to evaluate the impact of modular testing on TCIC. Modularization allows functional testing and system testing activities to be moved from the installation stage to the fabrication and assembly stages, with a subsequent reduction in labor cost and total construction time. TCIC sensitivities were performed on the fraction of testing activities that can be moved from the installation stage. The number of these activities is dependent on both the design and the technologies used during construction. The analysis showed the positive impact of modular testing on TCIC and demonstrated how EVAL can be a tool capable of helping stakeholder decisions.