06/05/2026
Canada Has Connected a Small Modular Reactor to Its National Grid for the First Time — Making It the First Country in the Western World to Operate a Next-Generation Nuclear Power Plant at Commercial Scale
The global conversation about small modular reactors has been conducted almost entirely in the future tense for the past fifteen years — promising, planned, proposed, projected, targeted. Canada has moved that conversation into the present tense. Ontario Power Generation's Darlington New Nuclear Project has connected its first BWRX-300 small modular reactor unit to the Ontario provincial grid, delivering 300 megawatts of zero-carbon, fully dispatchable electricity to Canadian homes and industry in a milestone that positions Canada as the first Western nation to operate a next-generation SMR at commercial scale. The reactor, supplied by GE-Hitachi Nuclear Energy under a fixed-price engineering, procurement, and construction contract, was built in six years from groundbreaking to grid connection — less than half the construction timeline of comparable large nuclear projects — at a per-megawatt capital cost that Ontario Power Generation has confirmed came within 12 percent of the contracted budget, a cost performance unprecedented in recent Western nuclear construction history.
The BWRX-300 design achieves its cost and schedule advantages through radical simplification compared to conventional large reactor designs. It uses passive safety systems that rely entirely on gravity, natural convection, and compressed gas accumulators to achieve safe shutdown under all accident scenarios without requiring any active pumping or external power — eliminating the complex active safety system infrastructure that accounts for a large fraction of conventional nuclear plant capital cost. The reactor pool is built below grade, providing natural seismic protection and allowing a compact surface footprint of approximately 4 hectares including all support facilities. The containment structure uses a suppression pool design that passively condenses steam in accident conditions without requiring operator action or external cooling for a minimum of 72 hours.
Ontario's grid operator IESO has confirmed that the Darlington SMR's dispatchable output is already proving its value in the provincial electricity market by providing reliable baseload generation during the high-demand winter hours when Ontario's wind and solar resources are at their seasonal minimum. The federal government of Canada has approved loan guarantees for three additional BWRX-300 units at Darlington and is in advanced discussion with the governments of Saskatchewan and New Brunswick regarding SMR deployment to replace retiring coal generation. Poland, Estonia, and the Czech Republic have each signed technology cooperation agreements with GE-Hitachi following the Darlington grid connection, identifying Canada's successful SMR deployment as the proof of concept their own programs require. Canada did not just build a reactor. It built the template.
— Ontario Power Generation / GE-Hitachi Nuclear Energy, Canada, 2024