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Large Light Water Reactors

Large Light Water Reactors (LWR) are reactors generating at least 700 MWe using ordinary water as coolant. This includes boiling water reactors (BWRs) and pressurized water reactors (PWRs), the most common types of operating reactors in the United States.

Currently there are no large LWR designs under review by NRC staff. Applications for certification of large LWR designs include the ABWR, APR1400, AP1000, ESBWR, US-APWR and the U.S. EPR. The ABWR, APR1400, AP1000 and ESBWR have been certified in Appendices A, F, D, and E of 10 CFR Part 52.