You guys are right about heat and friction and loss, but forgot one thing . The concept that energy is NEVER "created" or even lost, it is just transformed into another form, ex gas has energy in chemical form and your ped changes it into mechanical enery and heat energy. The alternators on Duck's "car" can only transform the mechanical energy of the cars motion into electrical energy which is then stored in the batteries as chemical energy, it cannot create new energy, so you would have to use more power to keep the car rolling than if you didn't use the alternators at all. Now if you used a system to recapture some of the energy while braking you could help extend the battery life somewhat. I think this is called regenerative braking (or something close to that). If you want to hear my $.02 I think the key to the whole electric car thing is FUEL CELLS. All electric with no recharging time just replace the fuel in the cell and off you go again. I even saw where you can get a crude mini fuel cell to power your cell phone.