Ontario's flagship small reactor runs late, over budget

Small modular reactors are compact nuclear plants built to be cheaper and faster than traditional ones. They were supposed to be the fast, affordable answer to the world's power crunch. Ontario Power Generation just admitted its first one won't be either. On Nov. 11, the utility said its BWRX-300 reactor at the Darlington site will miss its October 2030 target. It will also blow past its $7.7 billion Canadian budget.

This is the reactor type utilities keep pointing to as the answer to AI's soaring power demand. Small, modular, supposedly quick to build in a factory and ship to site. Ontario's version is the first BWRX-300 ever built, anywhere. OPG blames its partner, GE Vernova Hitachi Nuclear Energy, for the delays, citing 'ongoing engineering' work. First-of-a-kind reactors almost always run late and over budget. That alone doesn't kill the technology. But it should lower expectations for every other SMR project promising to come in cheap and on time.

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Does this spook AI companies counting on new nuclear power? Probably not immediately. Tech companies keep signing nuclear deals even as costs climb, betting the power is worth almost any price. But each delay like this pushes the timeline for new nuclear capacity further out. That's happening right as data centers need power now. The gap between when AI needs electricity and when new reactors can deliver it just got wider.