How? Well, that's what this blog is about. Much, much more on that later. But for a crash course, see www.p-r-o-system.com.
I have been writing an online email newsletter for about a year, which you can read on www.wallingup.com. Those of you who are long-time subscribers know that I have a low opinion of electric cars, and that's what I'd like to rant about today.
About every other week an inventor calls me up to say he's just invented the electric car. I am amazed when this happens. Really? You're phoning me from 1890? That is truly astonishing!
One fellow said he wanted my help attaching a generator to one of the wheels of his car so he can recharge the car's battery as it drives. To quote the Great Dave Barry, I am NOT making this up. How could I?
People assume that because a car is "electric" that it will be good for the environment. I disagree, conditionally. High-efficiency cars today are about as stripped-down as they can get. Just a motor, gearbox and wheels, with someplace none-too-comfortable to sit. Now take that highly optimized car and ADD to it a load of heavy, expensive gear. Three things happen when you do this:
1. The COST goes UP.
2. The weight goes up and therefore performance goes down.
3. The true efficiency goes down.
As evidence I cite a recent Top Gear episode in which they track-tested a Prius against a BMW M5 with a monstrous, ice-cap-melting, polar-bear-snuffing 4 litre V8 engine. The BMW was driven right behind the Prius and so did exactly the same distance, speed and time. The Prius was driven to the limits of its capability, and the BMW had no difficulty keeping up.
The results?
Pious Prius: 17 miles per gallon.
Global-Warming Mobile: 19 miles per gallon.
Electric and hybrid cars offer only one advantage over standard cars: Regenerative Braking. This is the ability to recoup around 50% of the cars' kinetic energy (1/2 m v^2) and put it back into the battery. This allows hybrid/electric cars driven in slow stop & go traffic to vastly outperform standard cars in the same setting. But is this how we really want to drive cars?
If traffic is that dense and the roads that ill-planned, I'd rather get out & walk or ride a bike. Where I want a car is on the freeways and out in the country. And then, I want to drive at least 1000 miles before suffering the inconvenience of having to stop and fill up! What electric car can offer me that?
The only ways to truly make a car more efficient and better performing is to decrease the weight, the air drag and the road friction. The problem is that decreasing drag makes a car less safe because it is also less visible to other drivers, and limits the driver's own visibility, too. Why? Because to get the ultimate low air drag, you are laying almost flat on your back inches from the road surface. Think, "Luge." Also, reducing the tyre friction makes a car less safe because it also reduces the grip that the wheels need for cornering and braking.
Therefore the main game in automotive efficiency without sacrificing safety is all about weight savings. Turbos for example allow smaller, lighter engines to make the same amount of power that bigger, heavier ones used to. Currently, batteries of a given energy storage capacity are vastly heavier than a fuel tank offering the same driving distance. That increased weight may be offset by very expensive carbon-fibre body work (again of questionable safety by comparison to steel), and perhaps by eliminating some of the mechanical hardware found inside and underneath a car.
It is essential then that an electric car, at the very least, have no transmission on board. This is not always the case in today's electrics and hybrids, and it still does not quite compensate for the extra added weight.
Nor does it compensate for the inconvenience of having to charge up or swap out battery packs every 100 or 200 miles.
And don't even get me started on the future environmental impacts of mass-producing all the batteries that will be required, as well as disposing of them after a year or two.
So, if you think you have invented a better electric car, I for one do not want to hear about it unless it directly addresses the issues raised here. If you really want to help, work on battery storage technology instead. Or electronic motor torque control to eliminate the need for gearboxes and brakes. Or chassis-integral suspension for further weight savings. Use your imaginations in areas where it will do some good!
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