> I have an islanding system for my (house) battery and solar, so in theory, I could have a bidirectional charger whilst being off grid. However both my car and charger don't support that (my charger is also deeply shit, and has no local API access

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> The amount of sysadminig to make that work reliably means that no normal person is able to achieve it. The problem for consumers is that there isn't any motivation for manufactures to work together on this. because they want to vertically integrate.

We are in a very similar position. The issue is every company in this area is like you say: deeply shit with limited local API access. Setting up bidirectional charging in the UK is technically, really not that hard, especially with islanding handled at the household level.

Good luck trying to get someone willing to put their career and certifications on the line to actually do it though.

Part of the challenge is finding an electrician willing to work like a sysadmin and do things because they know how they work, rather than only doing things they've explicitly been taught as in line with (dated) regulations.