Feasibility Study of Supercritical Light Water-Cooled Fast Reactors for Electric Power Production

The use of supercritical light water as the coolant in a direct cycle nuclear reactor offers potential for considerable plant simplification and subsequent capital and O&M cost reduction compared to current LWR designs. In addition, very high thermal efficiencies of the power conversion cycles are possible. Because no change of phase occurs in the core, the need for steam separators as well as for BWR-type recirculation pumps is eliminated. Similarly, in a direct cycle the steam generators typical of PWRs are not
needed.

In this work, which represents a collaboration involving The Uhlig Lab, the University of Michigan, Westinghouse Electric Company and INEEL, the focus will be on corrosion and stress corrosion cracking testing of candidate fuel cladding and structural materials. During the first year of the project, we will conduct initial corrosion tests using the instrumented tube facility in our supercritical water autoclave facility. Unlike SCWO systems for waste destruction, these SCW systems will involve a high purity water coolant that will be exposed inservice to radiation that is likely to produce oxidizing species (O2, H2O2, etc.) that might significantly affect the corrosion resistance of the materials of construction.