We simply took a standard BMW Mini One, discarded the engine, the disc brakes, the wheels, and the gearbox. These components were replaced by four of our electric wheels, a lithium polymer battery, a large ultra capacitor, a very small ICE with generator (so small it almost fits alongside the spare wheel), an energy management system and a sexy in-car display module.As you may remember my conception was that there should be one electric motor per wheel, no mechanical drivetrain, with power reservoir in the form of a battery. I did not consider the importance of supercapacitors in acting as a very short term rapid power sink and source.
Perhaps this is the time to mention a few things about the piston engine used in most cars and trucks. Its problem is that it isn't a very good machine for driving cars and trucks. That's why there are clutches and gearboxes, so that we can maintain driving conditions within the power band and not stray too near the 0 torque of 0 RPM. Furthermore, to provide the acceleration we desire they have to have a lot of power left in reserve, rarely used, and this makes them large and heavy. Electric motors have none of these drawbacks. They have plenty of torque from 0 RPM and can rev much faster than is usual for petrol engines. As such they can drive a car from stationary right up to a very reasonable top speed usually governed only by the rev limit. The only problem with them is that, obviously, the electricity has to come from somewhere. Trains and trams can receive power directly from the grid, but cars trucks and motorbikes will not be fettered by centralised power distribution. Therefore they must store electricity in some sort of battery or have on board electrical generation. Hydrogen fuel cell technology creates electrical power directly from the fuel, but it is also possible to use the old fashioned piston engine to generate power via a typical magnet and coil generator. Given the difficulty of storing hydrogen, and the expense of its componentry, and the fact that the petrol engine is here now and has the benefit of a hundred years of research and development and the monumental pile of research cash flow it has experienced due to the sheer number of cars produced, I believe it is the right tool for the job. Turbine engines would be more efficient in every way, but they are significantly more costly and given the expense already represented by the necessary electronics it seems to me that turbine powered consumer vehicles are perhaps beyond the reach of the average man.
The Mini mentioned in the story has a 250cc two-stroke engine, which seems odd since they're trying to prove that you can use this technology to save the environment and two-stroke engines have very dirty emissions. This does follow the principle, though, that you use a classical internal combustion engine to extend the range of an electric car, given that batteries do not yet provide the range of a petrol tank. I firmly believe that they never will. It will always take longer to recharge a battery than fill up a tank of petrol or diesel or, perhaps, one day hydrogen. We will never be able to store enough energy in them to consider pure battery power as an energy store for consumer vehicles, especially those that drive all the time, like trucks and vans. Some form of fuel will always be necessary; to think otherwise is silly. Removing and replacing batteries at some sort of battery swap station is also silly. That's going backward in techonological terms. When horses were all we had you had to change them when they were worn out, now they are talking of doing the same with batteries? How stupid. The average man will never go for it, so it will fail, no doubt in my mind about that.
So until the fuel cell becomes a cheap enough power source, we will be left with some sort of petrol- or diesel-electric system, and that is fine with me.
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