Yes, I agree long-haul diesel trucks will be the first. They use so much fuel / year that system can pay back the capital cost. I think the first car use of exhaust heat will probably be for AC. The old Servel gas refrigerator is not a lot of capital (no motors, etc) and the exhaust can replace the gas flame. BTW, Einstein made some refinements to it, AFAIK, they added too much capital cost to eve be used. It is a very clever system, with no moving parts - would last longer than the car, trouble free. It may be best to just let it run year round and over whelm it in the winter with "free heat." As far as getting electric power, perhaps a little via solid state devices. Their efficiency is low (<5%) but that not too important as the exhaust heat was going to be thrown away. Mainly any exhaust heat system must not increase the back pressure.