Another point: The electric motor has better low end torque, than a gasoline/diesel motor. The combination of electric/traditional motor, allows for better low end performance. Most hybrids, at least my Prius, always, first moves in electric mode, before switching to standard power. Battery technology has improved, manufactures are still a bit reluctant to use the LiPo, (Lithium Polymer) batteries, best stored electrical power to weight ratio. There is a fair amount of education required about this technology, that is just now part of marketing. A light duty truck, 20 or 30 miles per gallon, would sell. IMO, Mike CT.