Nice. On Octopus Agile in GB the price already tracks the mix (roughly 2.2x day-ahead wholesale), so the carbon-aware tariff exists in the wild.

What bounds the response is not willingness but plumbing: which import/export products the supplier lets you pair, and the export limit on a single-phase connection (about 3.7 kW). I reconstructed a 200 kWh home battery on the published half-hourly rates for June to August: the exact optimum moves 50 to 60 kWh a day, and the connection is a bigger lever than the software by a factor of two to three.