Electric cars are destroying our environment
The recipe for perpetual ignorance is: be satisfied with your opinions and content with your knowledge.
Elbert Hubbard
The Problem
One of the newest fads in automotive design has been the all-electric vehicle. You might have seen billboards for the electric RAV4, or perhaps you've heard about Honda's newest electric car? Either way, you know the marketing scheme. Save the enviornment, buy electric. Protect the earth from the horrors of fossil fuels.
Now, I'll admit, the concept of electric cars is a neat one, but not for its environmental implications. Electric cars have a number of advantages over standard gasoline vehicles:
- Potential to support more advanced electornic equipment. Current gasoline engines are a terribly unreliable source of power, requiring car devices to be specially engineered and (therefore) very expensive.
- Being switched to electric vehicles will be great when our oil supply finally does run out. You know, in 1979...I mean 1989....I mean 1999...you get the idea.
- Reducing oil consumption reduces our economic dependency on the Middle East, and reduces the likelihood of re-electing war-mongering idiots based on such dependencies.
So, if any of those reasons were what you were thinking about when considering an electric car purchase, read no further! I support you 100%. But for those of you thinking that you were doing mother nature a favor, read on.
Electricity Sources
At the root of the problem is the source of your electricity. According to the most recent publication by the US Department of Energy, it comes from:
| Fossil Fuels | 81.218% |
|---|---|
| Nuclear Power | 11.201% |
| Hydroelectric | 03.100% |
| Solar and Wind | 00.172% |
| Other Sources | 04.314% |
So, ignoring little details like uranium waste, "clean" energy sources only make up 18.8% of the electricity produced in the US. Sure, the pollution from the other 81.2% is being produced somewhere you can't see it, so maybe its okay.
The Second Law
The laws of thermodynamics are quite clear when they state that you cannot get energy out of nothing. The second law, in particular, is interesting because it implies that for all natural (irreversible) processes, entropy increases. That means that natural processes are never 100% efficient, and some energy is always lost in the form of heat. Yes, perhaps you took an Intro. Chem. course in college and this is a familiar idea to you. What I'm getting at is that all devices, including your heart, car engines and batteries, lose energy when operating.
Charging and discharging a car's battery are both natrual processes, and both release heat. The best batteries today are about 90% efficient. Charging and then discharing the battery lowers the efficiency to 81%. Then, the electric motor's efficiency must be taken into account (anywhere from 50%-80% efficient, depending on the type of motor). Assuming 80% efficiency, that reduces the overall efficiency of the electric car to 64%.
So, ultimately, 36% of the electric energy put into the car is lost to heat dissipation. Ultimately, you end up wasting a large portion of the energy you thought you were saving. Not only that, but consider the inefficiency of the fossil fuel power plants (~40%) that you use to power your electric vehicle.
If you were naive, you might cry "but gasoline powered cars are much less efficient than electric ones!" To that I reply, take a look at this article, that estimates the efficiency of an electric car to be within 6% of a gasoline powered engine. Also, realize that the author is making an argument for electric fuel cells, and so has taken the lowest possible efficiency for a gasoline powered engine as his reference point. Petrol engines can be anywhere from 20-30% efficient, while diesel engines can be 30-40% efficient.
Encourage Fossil Fuels
Perhaps the most important point to get out of all of this is what will happen when more people switch to electric cars. There hasn't been a new nuclear power plant built since Chernobyl, in the US or elsewhere. Solar and wind plants generate negligible amounts of energy and hydro plants are expensive and limited by location. If more people were to switch to electric cars, the demand for electricity would be filled by--you guessed it--more fossil-fuel plants. That defeats the purpose, doesn't it?
That's All Folks
Next time you see an environmentalist touting their new electric SUV, please, put them in their place with your good-old gasoline powered nature-saving vehicle that happens to go twice as fast and doesn't need to be plugged into a wall socket at night.