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Rao, D. V.

Publications and source records attributed to Rao, D. V..

Special Purpose Application Reactors: Systems Integration Decision Support

Microreactors, also known as very-Small Modular Reactors (vSMRs) or Special Purpose Reactors (SPRs), are being considered for use in unique applications where other methods of megawatt level energy production are uneconomical or unavailable. For the purposes of this report, a microreactor is defined as meeting the following criteria: • Factory manufacturable • Easily transportable by truck, plane, train, and/or ship • Produce no more than 20 megawatt thermal (MWth) energy, in order to qualify as Hazard Category 2 under 10CFR830 • Maintains neutronic simplicity, allowing semi- or fully-autonomous operation In the United States (U.S.), there are two general types of microreactors under development: high-temperature gas reactors (HTGRs) and heat pipe reactors. These two reactor types may, due to their differences in working fluid temperatures, be more effectively suited to different use cases. Additionally, they will require different interfacing components depending on their intended use. This report identifies a broad range of use cases for micro-reactors. Additionally, multiple reactor technologies are examined with an emphasis on the reactor sub-systems and interconnections. Using this information, a decision framework is developed to guide future efforts.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Database of Previous Research Supporting Microreactor Designs

This report provides a list of previous research supporting microreactor designs. For the purposes of this report, a “microreactor” will be defined as a reactor designed to produce less than 20 MW thermal while ensuring that the system is factory manufacturable, transportable (via truck, rail, or aircraft), and maintains neutronic simplicity (e.g., external controls) that can enable safe operation under semiautonomous or autonomous operation. The 20 MW thermal limit is based on the U.S. Department of Energy limit for a Hazard Category 2 (per 10 CFR 830 and DOE-STD-1027). Above the Hazard Category 2 limit, licensing activities would be required to be more detailed and robust. This does not eliminate higher-than-Hazard Category 2 reactors from consideration, but an increase in requirements typically means increased cost and time for development. Similarly, neutron simplicity is vital for minimizing the number of on-site operators; in turn, this enhances cost-competetiveness. Complicated designs do not eliminate reactors from inclusion in this report.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗