BWRX-300
Overview
300 MWe Gen III+ boiling-water small modular reactor derived from the NRC-certified ESBWR, using natural circulation and passive safety systems, a 60-year design life, and proven GNF fuel. Designed for a power block that fits within two soccer fields and 24–36 month nth-of-a-kind construction. The first grid-scale SMR under construction in the Western world.
Unit 1 under construction at OPG's Darlington site (construction began May 2025; in service by end of 2030, four units planned); TVA Clinch River construction permit in final NRC review with the mandatory hearing set for August 13, 2026; up to 10 further US units planned under the $40B US–Japan program; selected or down-selected in Poland, Sweden, Estonia, Hungary and Saskatchewan; UK Generic Design Assessment completed December 2025.