Ontario’s premier said “everything is on the table” this week, including shutting off electricity exports to the US, after Trump’s new tariffs on Canadian goods took effect. He and the Canadian PM reportedly discussed a 25% tariff on power crossing the border. I read that with the specific déjà vu of rewatching an episode: Ontario tried the exact same move in 2025, enacted a 25% export tariff, then killed it a day after it took effect once tempers cooled. The whole arc, threat, brief enactment, retreat, ran about 72 hours last time. If electricity keeps getting treated as a bargaining chip that both sides already know will get folded back, that’s a strange way to run a grid that some other region is actually counting on for real megawatts. ISO New England is already fielding questions about what happens if Canada follows through this time. Grids don’t love surprises, comedy sketch or not.

Elsewhere, someone finally wrote up the July 22 PJM event properly: 3 GW of demand, about 3% of system load, vanished in an instant when Northern Virginia data centers flipped to backup power, then came back. At the time it was “no reliability impact,” system stable within minutes. The follow-up piece calls it a harbinger, and that tracks. The interesting failure mode was never a plant tripping. It’s thousands of megawatts behaving like one synchronized object, because nobody wrote ride-through rules for loads this correlated. PJM is drafting them now, the normal order of operations: build the fleet, discover what it does as a herd, then write the rule assuming it happens again.

And Commonwealth Fusion says its reactor is “about 80% complete” — a suspiciously precise number for a machine that has never once worked.

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