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To keep things organized I will try to respond to each post/point seperately.
MetroMPG - I had not seen that, very cool. I am a little bummed I wont be the first to complete such a project, but its almost strange that you don't see more projects like this because all the hardware is available "off-the-shelf" and its just a matter of putting it all together.
RH77 - Thanks for that link, I hadn't found that yet. You touched on an important point with the lpg - availability. I'd like to have the ability to take longer trips with this thing, and I don't want to have a massive fuel tank taking up precious space. That pretty much limits my options to diesel, and gas.
tjts1 - I hadn't really considered an off the shelf generator, though that would make things alot easier. My main reason for choosing diesel is the higher efficiency at turning fuel btu's into kw (do to lack of a throttle body for one). But my logic may have been flawed if each engine is running at WOT (minimal pumping losses) as a generator would be. Diesel does have the option of running off of straight vegetable oil. I am trying to keep my design as modular as possible so if this diesel/gen combo doesn't live up to my expectations I could always swap it out for a gas unit with minimal fuss. I do need around 10,000w continous (for 65mph cruising) and any normal generator of this size is going to be bigger and more expensive than I would like (my belt driven 10,000watt home made gen is about $800 total)
diesel_john - You make a good point about the direct coupled efficiency gain, I hadn't considered that. I bought a belt unit because it seemed like mounting would be much easier with a belt length that could be adjusted until everything fit in the rear nicely. The fact that diesel price has spiked recently is a bummer, the choice would be much easier if it were stil cheaper. As you probably know, a gallon of diesel contains more energy so this may make up for the price difference. As far as regen goes, my motor actually has interpoles already, which allows it to be used as a generator without arcing to death like a normal series wound would during regen. The main limitation is the motor controller. Mine does not support it, but if I'm willing to live with 1/2 the amp rating (500A peak) I could get a 144v controller with regen capability. I really, really want regen so I might make the swap at some point if it seems like 500A will be enough for decent acceleration. I suppose a generator in parallel with the motor would give me the same capability without the power sacrifice, at the expense of 100lbs. SO many possibilities....
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