Something I've long wondered about was why nobody has used the diesel locomotive paradyme, where an auto would have a smaller diesel motor than would be required for the car, which actually supplies power to an electric motor, which drives the car.
Mark
Energy is lost when you convert it from one form to another. In the case of diesel locomotives, this is necessary to produce the very high torque you get from the electric motors that move them. In cars, it is simply more efficient to directly drive the car from gasoline combustion, rather than have the engine drive a generator to create electricity which then is used to drive the car.
I have wondered, however, how the numbers would play out if you used a high efficiency gas turbine engine rather than a standard ICE. That would bring with it other issues though...
Anytime you transform energy from one type to another you incur losses. The Diesel engine converts chemical to kinetic energy with great losses (~50%). If you then convert the kinetic to electric you get even more losses. You then convert electric back to kinetic, even more losses.
Locomotives do it for 2 reasons. They need instantaneous torque to move all that weight from a standstill and they need to be able to shift while under load, so designing a traditional gearbox for the diesel engine is pretty difficult. An electric motor gives you instantaneous torque and needs no gearbox. So they trade the conversion losses for the 2 gained benefits. But if you made a car with this concept you would get even worse gas mileage than this poor deluded Honda owner.
That is called a series hybrid. The Chevy Volt does that, except in severe conditions where the engine is directly linked to the transmission. Most of the time, it only drives a generator which feeds the batteries and thereby the electric motor.
While it is true that conversions of energy entail losses, it is also true that a gasoline engine is very inefficient when it has to push a variable load as all regular automobiles do. When it runs under a steady load, it is much more efficient — this is why your best mileage in a regular car is at moderate speeds on flat ground with no stops. A series hybrid is enough more efficient that the losses in charging the battery and driving the electric motor still result in lower fuel consumption.
It is probably a matter of scale.
Diesel electro-motive works well in industrial apps like locomotives and drilling rigs (yes, THAT is how the well is drilled) but in something as small as an automobile? Probably not.
If it did we’d have tractor trailer rigs powered that way.
Check out the Wave Disk Engine. It’s like a combination turbine & rotary engine that will be used to power the next generation hybrids.