Hmm, I was basing my thinking on what they are actually getting out of diesel engines vs gasoline engines. WOT wouldn't necessarily be what's needed either. The engine speed would need to be matched to the generator's most efficient RPM. If necessary, a gearset could be put between the engine and the generator to allow the diesel run at it's most efficient RPM level, and still turn the generator at its most efficient RPM level. Nice thing about this is, the genset does not have to run depending on vehicle speed. But as you guys say, could use gasoline too. My preference would be to run a diesel with a particulate filter on the exhaust, since this would give me the option to pick up veggie oil for 75 cents to a dollar a gallon provided I buy it by the ton (and a ton of oil is about 250 gallons).
Another nice thing about this idea, it looks like it could fit under the hood of my pickup. I did some searching around on the electric motor part of this, and found that the electric motors being used for conversions are not really any bigger around than my transmission body, so I could get a tranny with no bell housing, slide it back, and hook the electric motor directly to the trans with the motor sitting where my trans is now. Plenty of room for a genset then (and shows yet another advantage of the rear wheel drive vehicle ). There is even a few motors that come with Chevy TH400 output shafts installed, allowing a direct hookup to the existing driveshaft, no transmission needed at all. Not sure if that would produce enough power to get the speed I want though.