Likewise, there are plenty of plug-in hybrid cars which ought to be great home emergency backup generators (ie. they have a 40+ kilowatt generator and 7+ kilowatt inverter), but very few have this functionality even if the hardware in most cases supports it and would simply require a firmware update.
I had good luck with telling claude to rewrite my laptop bios to enable various power modes which were theoretically possible but disabled by firmware, like powering a fullsize screen from the laptop battery over usbc.
Maybe I'll tell claude to rewrite the car firmware too...
I know someone that did this with an old Prius. No software hacking required. Just leave the ignition on, and wire into the high-voltage system (not at the same time, of course!). The engine auto-starts when the battery gets too low.
The more interesting approach is to do it with a used EV. You can get a 100-133 kWh car used for $20-30K. The last time I checked, that was below the price of a house backup battery with a quarter the capacity.
Be sure to alert the fire department ahead of time.