Sunday, June 17, 2007

How much does it cost to drive an Electric Car?

I often am asked how much it costs me to charge my electric car and how that compares to a gasoline powered car. There is no question that the electricity required for my 30 mile commute costs much less than the gasoline required for the same commute. This is largely because an electric vehicle is much more efficient than a gasoline vehicle, but also because electricity in the Pacific Northwest is not nearly as volatile as gasoline prices. Using my latest bill from Tacoma Power I see that our electric rates are .03 cents per KH for consumption and .03 center per KH for delivery. I have no idea why they break the bill up like that, I don't think I'd feel any better if they charged me $1.00 gallon for milk and $1.00 for delivery to the grocery store, but oh well, I'm sure there is a great reason for it. I know from a recent cool device I purchased for $20 called the "Kill-o-watt" how much electricity it takes to charge the car on a daily basis. Using the "Kill-o-watt" which plugs in to your wall, and then allows a device to plug in to it, and measures the current passing through I know that it takes 14 KWH of electricity to charge the Electrc Saturn. So, my total daily cost is $0.84 for the 30 mile round trip. Hmm, now lets compare that to what I got in my 1996 Plymouth Voyager which gets 22 miles to the gallon. 22 miles to the gallon, at $3.50 per gallon (yes I know that regular has dropped below that, but who believes it will stay there long? And I'm a physicist so I believe in liberal rounding) I find that the same trip cost me $4.76 per day. So, I have a savings of $3.92 per day when driving my electric vehicle. Wow, not bad!! Since I drive at least 30 miles per day 6 days a week (usually I drive between 30 and 40 on Sat/Sun combined) I find that my weekly savings is: $23.52.

Is that the last word? No, because I still have to factor in regular battery replacement, but that is still good enough for today, and I'll factor in the batteries when I have a better idea of how long they will last.