Hendler posted something like that the other day. I'm very doubtful that there's any advantage to the on-board water cracking system. Cutting the water apart takes energy. Some of it gets lost. The H20 tank and cracking equipment weighs something and gets carried around. This is extremely unlikely to create any advantage.One way of utilizing heat is to heat up water and split the hydrogen and oxygen and feed into the range extender engine. Little electricity is needed if water is heated and you'll recover more from the heat energy.
Here's a new concept car recently shown that uses hydrogen on demand via onboard electrolysis of water:
Thanks. Here it is, Honda Rankine Cycle -click 1/3? And the rest. Having ancillaries all electric, then this would be feasible if sized properly. But it gets complicated. BMW claimed 20% better fuel consumption, by elimination of parasitic engine loses.
The efficiency is dire. That is why a small Stirling or Rankine unit is better to turn an alternator.I remember seeing articles on thermoelectric generators on the Chevy Suburban exhaust could provide 1 mpg and 800 watts at highway speeds. No mention of cost though. Searching around the web, it looks pretty expensive to add to the vehicle; maybe on the order of $10 per watt.
Depending on size, the cost will come down as they always do, it may be worth having a large version of this heated only by a small diesel oil burner to make electricity. All Solved!!You should be able to get a descent output from a thermal electric generator from the tailpipe. A 150hp car should produce several Kw of peak power from a well designed TEG. From what I understook one of the big drawbacks is the cost.
I found this while looking around for numbers. It looks like it could be very promising for making such a setup cost effective
Stripping heat from your exhaust has a cost too. The hotter your exhaust pipe, the thinner the air, the easier it can be expelled from the system.can run off waste exhaust heat. I believe Cadillac were using one.