Re: "GM is projecting an all-electric future..."
"Generator != Engine"
The generator is a motor attached to an ICE - an engine.
Well done, you've just designed the vauxhall ampera.
Also a 3kW generator isn't going to do you much good, you'll want at least 15kW, probably 20kW (70mph at 5m/kWh is 14kW, at 4m/kWh it's 17.5).
And now you have an engine, a fuel tank, and all the servicing that is associated with those.
A 10kW generator (the largest "small" unit I could easily find) masses 150kg.
That's enough for 40+kWh of LiIon (or 160 - 200 miles of additional range)
And battery prices are ~£100/kWh, so that's a £4k battery pack, rather than a £2-3k underpowered generator.
It just doesn't add up in favour of a generator.
Add the opportunity for using vehicles with "oversized" batteries as grid storage - and getting paid for that. Let the grid charge/discharge your vehicle, with a lower limit to ensure you have enough juice to go anywhere you need. Just raise that limit on the day before a long journey.
Or as a domestic UPS for the house...
Or .... plenty of things I haven't thought of.
"Also your 100kW charges ain't going to happen because where has an electric supply that will support that? You'd have to replace the local substations, the cables to the house, and the internal fuseboxes which will no doubt happen at the same time as fibre to the premises (aka; never) due to the absurdly high costs involved for most properties."
Well at home you don't need more than 7kW (and only ~5kWh/day on average).
At service stations, you need a decent power supply - but they already have decent power supplies.
I'd like to see SMR deployment at all 150 motorway services, free heat for the services, locally produced energy for the chargers, export surplus power to the grid, import if you suddenly have a huge number of cars pulling power.