comparisons which are starting to annoy
Aug. 11th, 2009 02:43 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
walkitoutI recently remarked that since food and fuel are both measured in kCal, it is possible to figure out, for a particular human, what their equivalent miles per gallon is, altho I definitely left the details as an exercise for the reader.
In any event, the other day GM announced the mpg for the upcoming Volt, which somewhat mystified me. I mean, it's an electric car that you can plug into the wall and has a 40 mile range (really? hills or flat? going how fast? stop-and-start or highway? AC or not? and how many people in the car. I mean, is this one of those, it gets 30 mpg in our testing, but you'll never do better than 22 -- or you'll average 44?). Apparently, there are government rules about how you would calculate mpg for such a vehicle (where the gas part of the equation only kicks in after that 40 (odd) miles, and then only to recharge the battery). And those rules came up with over 200 [ETA: previously typo-d as 300] mpg, thus assuming that the juice coming out of the wall doesn't count towards running the car. In much the same way the transportation decision makers figure it's a benefit, not a cost, that bicycling and walking consume food energy.
I mean, if you're going to engage in some sort of calculation that comes up with 200 [ETA: previously typo-d as 300] mpg, how much harder would it be to engage in a calculation that produced an equivalency between kCal and kwh?
ETA: It's all the fault of crappy coverage. That's my story and I'm sticking to it. The EPA did, indeed, address this issue:
http://www.greencarcongress.com/2009/08/230-20090811.html
ETAYA: Oh, and it's _up to_ 40 miles. Which is not as helpful as it could be. After all, both our gas-only cars travel up to 40 miles on a charge. That would be zero, of course, unless your trip is entirely downhill...
In any event, the other day GM announced the mpg for the upcoming Volt, which somewhat mystified me. I mean, it's an electric car that you can plug into the wall and has a 40 mile range (really? hills or flat? going how fast? stop-and-start or highway? AC or not? and how many people in the car. I mean, is this one of those, it gets 30 mpg in our testing, but you'll never do better than 22 -- or you'll average 44?). Apparently, there are government rules about how you would calculate mpg for such a vehicle (where the gas part of the equation only kicks in after that 40 (odd) miles, and then only to recharge the battery). And those rules came up with over 200 [ETA: previously typo-d as 300] mpg, thus assuming that the juice coming out of the wall doesn't count towards running the car. In much the same way the transportation decision makers figure it's a benefit, not a cost, that bicycling and walking consume food energy.
I mean, if you're going to engage in some sort of calculation that comes up with 200 [ETA: previously typo-d as 300] mpg, how much harder would it be to engage in a calculation that produced an equivalency between kCal and kwh?
ETA: It's all the fault of crappy coverage. That's my story and I'm sticking to it. The EPA did, indeed, address this issue:
http://www.greencarcongress.com/2009/08/230-20090811.html
ETAYA: Oh, and it's _up to_ 40 miles. Which is not as helpful as it could be. After all, both our gas-only cars travel up to 40 miles on a charge. That would be zero, of course, unless your trip is entirely downhill...