To me it is obvious that the way to go would be to abstract out the power source by using an electric drivetrain regardless of the engine. When the car has elec

To me it is obvious that the way to go would be to abstract out the power source by using an electric drivetrain regardless of the engine. When the car has electric motors connected directly to drive shafts you can eliminate lots of the mechanical linkage and you are also free to redesign and relocate the power source as you wish. But, most importantly, once you accept the slight inefficiencies in converting energy to electricity and then to radial forces, you are free to experiment with whatever power source you like: - use batteries like Tesla: you can simply fill with batteries any compartments of the body that you wish. The car runs as long as the batteries have charge. - use fuel cells if those ever become viable. - design a small, self-contained turbocharged diesel engine that runs at the optimum RPM to drive a generator when the batteries need charging: put it in the boot or the front bay, but you don't need to consider how it connects with the wheels mechanically, and it can be lighter and doesn't have to support a wide range of RPMs like current engines. - or maybe linear generator engines powered by gasoline or diesel (like what Toyota has been developing) turn out to be optimal for mobile electricity generation for some period in the future. - or maybe a low-cost turbine engine hooked to a generator like the Whisper concept car: the engine can burn nearly anything and provides high power output at high RPM that would otherwise be in the impractical range for a car. But if you combine any power source and a small battery, that allows you to buffer energy and only use the combustion engine to occasionally recharge the battery. You can drive the rush hour traffic or a downtown route using mostly electric power only, and rely on the combustion engine to recharge the battery when parked (but not plugged in to mains) or while driving during longer trips. A reasonable compromise for range anxiety would be to drop down to limited power when the battery runs out and you need to rely on the combustion engine only. You could still reach your destination but at slower speeds. Nevertheless, the options are quite unlimited. Buffering of energy is more useful than raw power in the future just like an Android phone is more useful than a desktop PC in the general case even if it's slower and runs only a day or so without charging. Only serious usage warrants desktop PCs with stationary power supplies: most online activities can be done with a low-power device that runs on energy buffered in the battery.