ENERGY USE IN WH/MILE FOR THE FIRST 2,000 MILES
Here below is my energy use for the first 2,000 miles of driving. Below, I'll estimate the total cost based on my cost of kWh/mile, and I'll be happy to add what I actually paid when the bill comes, as the car is on its own meter.
About 800kWh to go 2,000 miles.
My average of 395 Wh/mile includes many inefficient test rides (sharing the Tesla Smile), some very cold weather driving (several days below 10 degrees, several below zero), mountain driving (read: Hills). At home, I pay - off peak - 5.5 cents/kWh. But I charged in Nh as well at about 16 cents/kWh. My average (a guess) would be about 8 cents/kWh, or about $64 to travel 2,000 miles. This does not account for mileage lost during cold days with the car sitting at my workplace, which I'd estimate is more considerable than I'd have guessed pre-onwership. But I think it fair to say I lose no more than 40 miles/ full charge cycle to the cold, or about 9 full cycles, or 360 miles lost to the cold. At 8 cents/kWh that is about $29, for a total estimated cost of $64 plus $29, before insensible (charging AC-DC conversion related) losses. If these are about 10%, then let's add $8.30 for that and call it $64 plus $29 plus $8.30 = Oh let's call it $90 for 2,000 miles.
$90 of gas = 26 gallons at $3.35/gallon, and my old car, RIP, would have gone 28 miles/gallon, so 28 miles/gallon x 26 gallons = about 750 miles, or about a 3:1 cost difference/mile.
That is, I think, the grimmest measurement I can do, optimizing the ICE costs and maximizing the electrical charging costs, driving INefficiently and at cold temps. When I estimate this in a more favorable light, I see a cost of about $70 total for 2,000 miles of driving.
Update: at 2,500 miles I had used almost precisely 1000kWh, or 2.5 miles/kWh. That, it appears, is my realistic winter mileage. Disappointing a bit that my mileage is well-below the 3.3 miles/kWh I'd anticipated, but warm-weather will improve mileage significantly. But, in reality, I drive this car much faster than I might have anticipated, and therefore, my mileage will not be as ideal as my driving experience...
Here's an update as of May 9, 2013, at 9,000 miles: I have got a total of 8843 measured miles (my actual mileage is 9177, but I did not start measuring my usage until a little after getting the car). I have averaged 367 watt hours per mile over that time, but that includes deep winter, much of it in New Hampshire and below or at 0°. During that time I averaged 395 watt hours/mile.
Over the past 3000 miles (about April 15th-now), I have burned over 900 kWhours (about $70 :smile
for a total of exactly
326 watt hours per mile. Even that is high compared to my more recent mileage, where I am averaging at or below 300 watt hours per mile. In fact, over the past three days,
I have averaged over 300 miles per charge. And though I'd like to tell you I drive slowly, I do not...
I think there are two reasons for this significant decrease in energy use/mile - one is the warmer weather, in which the car is about 10% more efficient, on my own experience. The second, however, is that the more I drive the car, the more I learn to be more more efficient in the way that I drive, while still fully enjoying this car's tremendous acceleration. In short, my driving is becoming more and more efficient although I fully enjoy the tremendous benefits this electric drivetrain provides. My total cost of charging for 9000 miles is about $200. Wow.
