Thursday, July 27, 2006

An EV as a second car

When the topic of electric vehicles (EVs) comes up, people always seem to think that they are a decade or so away from being good enough to be useful. They're thought of as interesting, as a good idea, but not something this is practical or that there is a market for right now. The reasons for that are something like this: 'They are too expensive', 'EVs don't have enough range, people need their cars to go farther than that.', 'They won't last long enough', or 'Electric cars aren't powerful enough'.

First of all, electric motors can be made more powerful than needed to move a car. Most diesel trains are actually electric trains with diesel generators. Most every engineer knows that you can get far more torque out of an electric motor than a engine of the same size.

Second, the longevity issue. Electric cars are more simple than their gasoline counterparts, due to the fact that they do not have any of the following: radiator, injection system, ignition system, gas tank, gas pump, timing system, belts, oil or cooling system, ETC. Because there are far fewer parts, lower pressures, and lower temperatures in an electric car, EVs tend to last longer. The batteries may need to be replaced every half decade or so, but thats how long some gas cars are kept anyway.

Third, the range and expense issue. The problems presented in these areas are quite correct, if the electric car is to be your primary or only vehicle. However, if it is a secondary car used for running errands, it would not need more the maybe a one-hundred-fifty mile range. By observation I would guess that, for most demographics, the great majority of the distance they travel comes from trips less than one-hundred-fifty miles long. If you had two cars; a regular fossil fuel one and an electric one, and the gasoline powered car were to be used only on the trips exceeding the electric car's capability, very little gasoline would be used.

Think about this example: A family has a SUV that works fine for everything they need, except for the fuel efficiency.
For the sake of simplicity lets say that the price of an electric minivan is the same as that of the normal minivan. Lets also assume that the price per mile driven in the cars is as follows: $.20 per mile for the SUV, $.12 per mile for the Minivan, and $.04 per mile for the electric car. Lets also say that 10% of the driving distance requires the SUV, 20% requires long range capabilities, and the remaining 70% can be done with the electric car. So, with these numbers let's calculate the cost per hundred thousand miles.

Option 1 (which is all that is currently available):
They buy a minivan seeking a more fuel efficient vehicle that can still fit all of them and their stuff. It works reasonably well; they only use the SUV for rough terrain and hauling large loads. The minivan in now used for almost all of the driving that takes place. Here, the SUV would only drive 10% and the minivan would drive the other 90%.
SUV: 10,000 miles times $.20 per mile equals $2,000.
Minivan: 90,000 miles times $.12 per mile equals $10,800.
Total: $12,800.

Option 2:
They get an electric car with a range of only one hundred fifty miles. They use the SUV for the long trips, such as vacation, in addition to the hauling. The SUV is driven more than in option 1, but the increased use is offset by the fact that it is the sole consumer of gas. In this scenario the SUV would be going 30% of the total distance and the electric car would take the remaining 70%.
SUV: 30,000 miles times $.20 per mile equals $6,000.
Electric car: 70,000 miles times $.04 per mile equals $2,800.
Total: $8,800.
Amount saved verses option 1: $2,000 per 100,000 miles. This figure does not reflect the reduced maintenance cost of operating an electric vehicle over one burning fossil fuel.

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