“An on-board electrical generation capability, using some heat source to drive a Stirling-cycle hot air engine (or even a steam engine, we don’t care), which in turn drives a generator that supplies the electrical energy to drive the wheels would appear to be one of the better engineering designs to follow.”
Uhm-m-m ... whats with the exotic power sources for the generator? The Toyota Hybrids are already here and have a small ICE for the generator - no new engineering miracles needed.
I think Toyota has an hev. Hydrogen electric vehicle. They did a range test with it driving fairly slow. Got more than 600 miles. Uses hydrogen canisters. Trade in the empty canisters for full ones.