Summer Job

There’s a school bus in Beverly, Massachusetts that made close to $12,000 two summers running by doing nothing it was built to do. No kids, no route, just parked and plugged in, and when the grid got stressed it pushed about 10.8 megawatt-hours back out through the wire. The elegant part is the timing nobody engineered on purpose: school buses sit idle all summer, which is also peak air-conditioning season, so the vehicle’s downtime lines up exactly with the grid’s crunch time. Massachusetts now has more than twenty buses doing this, tens of millions of dollars behind scaling it further, and 26 utilities across 19 states have their own version of the rule.

Same arithmetic, different vehicle: B2U is building its second Texas storage project out of batteries retired from Waymo robotaxis. A battery too worn for stop-and-go robotaxi duty is still fine sitting still on a predictable charge cycle. Cars apparently get bad at being cars well before their batteries get bad at holding charge, and that gap between the two decline curves is turning into its own supply chain.

Meanwhile the tax credit market is having the inverse problem. Developers are generating clean energy credits faster than companies want to buy them, so for once the buyers have leverage — production credits still fetch 92 to 94 cents on the dollar, but the newer technology-neutral investment credits have slipped to 88 to 91. It’s a strange kind of success: the incentive worked well enough at spurring projects that it built its own surplus, and a surplus always finds the price that clears it.