Electricity: Not Magic

electric_emperor The official story is that the “electric” car is going to save capitalism.

I put “electric” in quotation marks because electricity is always made from something other than itself, usually fossil fuel combustion or nuclear fission.

But it is also important to notice that denial of sources is not the only layer of magical thinking inherent to the growing cult of the electric car.

The second layer has to do with the inherent inefficiency of electricity generation and use.

To understand that, take a look at this excellent article by Kris De Decker at Low-Tech Magazine. De Decker explains the basic physical facts about the inescapable problems with burning energy to make electricity:

First of all, it is important to know that generating electricity is far from the most efficient way to apply pedal power, due to the internal energy losses in the battery, the battery management system, other electronic parts, and the motor/generator.

These energy losses add up quickly: 10 to 35 percent in the battery, 10 to 20 percent in the motor/generator and 5 to 15 percent in the converter (which converts direct current to alternate current). The energy loss in the voltage regulator (or DC to DC converter, which prevents you from blowing up the battery) is about 25 percent.

This means that the total energy loss in a pedal powered generator will be 42 to 67.5 percent (calculation example for highest loss: 100 watt input = 80 watt after 20% loss in motor/generator = 57.5 watts after 25% energy loss in voltage regulator = 37.5 watts after 35% loss in battery = 32.5 watts after 15% loss in converter = 32.5 watts output = efficiency of 32.5% or energy loss of 67.5%).

De Decker also touches upon another decidedly non-magical aspect of electric machinery — the ecological and energy problems with batteries and steel:

[T]he embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles, you are basically pedaling to produce the energy required to manufacture the battery.

Lead acid battery Of course, it also takes energy to manufacture a pedal powered machine that does not take the intermediate step of generating electricity. This concern lies mainly with the production of steel, and quite a lot of it. The commercially available Fender Blender mentioned earlier weighs 25kg (55 pounds).

If made from recycled steel, and using these figures to calculate the embodied energy of steel, this comes down to an energy cost of at least 41,625 Wh, slightly more than the battery needed for the electricity generator. If freshly made steel is used, the embodied energy is at least 138,750 Wh (3.7 times the embodied energy of a single battery).

De Decker’s conclusion?

When operating a bicycle generator you are basically pedaling to produce the energy required to manufacture the battery.

All these costs apply to automobiles, too, despite their indispensability to capitalists. Imagine how that pencils out!

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