Regenerative breaking on MMM

That's the idea.

Originally Posted by BrianG

Could use a BL motor and use a 3-phase bridge rectifier, since that is somewhat how an alternator works...

No matter what, the energy you expend will be more you capture because of efficiency losses. But, if your biodiesel engine can be freed from the stop and go part (and the inefficiencies that entails), maybe it will overcome the inefficiency of the added electric motor drag.