G:TB is generally concerned with the critical topics of our time, like ensuring that TJ gets enough beauty sleep and merrily skewering people far more famous than us. But every once in a while we come across a nugget of real-world import that strikes our fancy. Ruminate on this:You save more fuel switching from a 15 to 18 mpg car than switching from a 50 to 100 mpg car.
Don't believe it? Check out the math here. This is really reassuring. We don't have to go get that Prius now when our Durango shuffles off this mortal sparkplug. We can get by with another SUV that gets thismuch better mileage and still look Al Gore in the eye.
it's from a 16mpg car to a 23 mpg car, versus a 32 to a 47-- and all that means is that there's a greater percentage of change from 16 to 23 (almost 50%) than from 32 to 47 (a bit less than 50%) but if you think about it with easy numbers, you realize that it's not enough. if you drive 100 miles a year, with a 50 mpg car you need two gallons of gas. with a 20 mpg car you need 5 gallons. with a 25mpg car you need 4. of course there's diminishing returns as you get to the super-car, but the energy required to make a new car that saves a gallon of gas every hundred miles outweighs the cost of saving that gallon of gas. if you're going to buy a new car, it needs to save a LOT of gas to offset the manufacturing process-- that's why it still takes way too long to save money and energy with a prius. some scientists also did some math and often it's better to drive than walk-- because you burn more energy walking and have to eat more food, which leads to greater carbon emissions somewhere int he world where they're raising the meat you will eat because you walked.
ReplyDeletethere's another reason that curve is wrong (these kind of things bother me). it LOOKS more dramatic at the low end, but that's only because all of the miles per gallon are represented. if it were evenly spaced plots for 16, 23, 50, and a hundred then the line would look far different and the percentage change would be reflected more accurately. 50 to 100 is actually a larger leap than 16 to 23 (and of course 15 to 18) but it LOOKS less dramatic when you plot every mpg in between-- that smooths out the curve.
ReplyDeletein terms of marginal fuel used, the math is accurate and the curve is correct. over 15,000 miles you'd save 167 gallons going from 15 mpg to 18 mpg and only 150 going from 50 mpg to 100 mpg. i think the point of the article is that we'd be wise to push for increased fuel efficiency standards at the lower end of the scale, because that's where so many more vehicles on today's roads reside.
ReplyDeleteof course, the 100 mpg vehicle is the best option, but a) they don't exist, and b) they won't anytime soon. let's make progress where it's most achievable in the short term.
read the new wired magazine-- there's a contest going on now to build a mass market 100 mpg car-- and there are already ones that do it-- they're just not ready for manufacture. and i guess i shouldn't say the curve is wrong, but it just makes things look more dramatic-- the reason more gas is saved at that low end is because you're still using a shitload of it.
ReplyDeletesure - that's right. i guess i'll take progress anywhere i can get it. our grandchildren will wonder how the fuck we ever got ourselves into this mess, as they drive their hydrogen cell hovercars around.
ReplyDeletethat's a cool article - i like the idea of competition driving innovation. still many years away from having those things commercially viable, though.
ReplyDeletei'm hoping our next car-- barring complete breakdown of our current one, will be something like that-- and going from a 25 mpg car to even a 50 mpg car-- which is what most people who are heavy drivers will hopefully do-- DOES save more gas than going from a 15 mpg. car to a 20 mpg car-- 2 gallons saved every hundred miles versus 1.6 saved every hundred miles . . .
ReplyDeletei also read something that said if everyone really did start walking then there would be pollution problems from all the particles from the shoe soles. seriously, so we can't win.
Wow, so serious. I'm just trying to keep one of my dogs from humping the other.
ReplyDeletenow if you could harness some of that humping action, you could power your household for the next year or so. that's a whole new source of clean energy.
ReplyDeletehumping is not clean. neither is porking, fucking, banging or screwing. making love is clean.
ReplyDeletethere is no appropriate transitive verb for porking. you have to use a prepositional phrase: i made love TO wanda; i had sex WITH gertrude. maybe impregnated? but that's different.
How about "I boned Mrs. Pellicane?"
ReplyDeleteDon't overlook the amount of energy required to make the gasoline itself. We have to drill for oil, extract it, transport it to a refinery, refine it, then ship the refined material to your local filling station. This all takes energy. I have no idea how this affects consumption on the margin though.
ReplyDeleteI pumped Zoltan's mom in the gashole.
ReplyDeleteI distributed my fuel into her crankshaft.
ReplyDeleteI also slipped my dip-stick into her oil slot.