Advanced Reactors

This article is the first in a series that will examine the history of small modular reactors.

Small and medium reactors have been an integral part of the U.S. nuclear power enterprise since the early days of the industry. Many of the designs for the next generation of reactors are rooted in the designs of the 1950s and ’60s, but the development and push for deployment have gained momentum only within the last decade.

This recent momentum led a reader of Nuclear News to suggest an article reviewing the history of small modular reactors. NN staff jumped on this idea, deciding a series of articles would do better justice to such a complex and interesting topic.

Dennis Henneke

The BWRX-300 is the 10th generation of boiling water reactor designed by GE Hitachi and has a number of evolutionary features. We learned from the design of the Economic Simplified Boiling Water Reactor (ESBWR), the BWRX-300’s predecessor, that implementation of a plant design that utilizes passive safety features can result in a relatively large containment. From the inception of the BWRX-300, our goal was simplification of the design and the reduction in overall size of the “safety footprint,” which includes both containment and the safety-related--component plant areas. The design team was empowered to consider any and all simplification efforts, which were evaluated by the GEH team. One key to implementing this goal—design of a plant that can be licensed anywhere in the world—is the use of a probabilistic risk assessment (PRA) that helps ensure the resulting plant risk is low.

The Advanced Reactor Codes and Standards Collaborative (ARCSC) held its second workshop on November 30, 2023, in Washington, D.C. The hybrid event had just over 200 participants, including representatives from standards development organizations (SDOs), the Electric Power Research Institute, the Nuclear Energy Institute, national laboratories, government agencies, vendors, advanced reactor designers, and consultants as well as representatives from other U.S. industry and international organizations, including the International Atomic Energy Agency. ANS Standards Board chair Andrew Sowder, senior technical executive at EPRI, welcomed attendees to EPRI’s offices, where the workshop was held.

The Gateway for Accelerated Innovation in Nuclear (GAIN) announced December 19 that seven firms will get vouchers to access the nuclear research facilities and expertise of the national laboratory complex in the first round of fiscal year awards. Each company is paired with one or more national laboratories to work on concepts from advanced reactor fueling to fuel recycling to climate forecasting.