Alright, I’m an advocate of not driving more than need be. I’m kind of lazy, so I’m not always a good advocate. However, you’ve got to use your body to keep it working. That’s the neat thing about a self-maintaining machine. Anyway, that said, let me get to my quick point. I’ve seen a number of comments from treehugger ecogeeks about the amount of calories a car consumes daily versus the amount of calories our bodies use. It’s interesting stuff, but there’s a point I see missing often times. Cars carry heavy stuff (if only itself) across long distances very quickly. So lets play with some numbers.
First, there’s this popular link over on GOOD showing the amount of calories in gasoline. Meanwhile there’s a considerably less popular link to NutriStrategy’s calories burned per exercise. From the first link, we know that gasoline has 31,268 calories per gallon. A Ford Escort gets upwards of 40mpg. Lets make the math easy and say it gets 31.268 mpg. (See what I did there?)
31,268 cpg / 31.268 mpg = 1,000 calories per mile
This car weighs almost 2,500lbs. The average American is slightly lighter. According to that NutriStrategy chart, running at 10mph for 1 hour burns 1126 calories for a 155lbs person. Can you run at 10mph for a full hour? Holy crap. Anyway, lets pretend you can. In 1 hour at 10mph, you’ll run (approximately, I’m no mathematician) 10 miles. (See, I’m doing it again.) So, lets do the math.
1126 c / 10m = 112.6 calories per mile
Neat.. so we’re looking at a car using somewhere between 8 and 9 times as many calories per mile. Now less toss weight in. The car was 2500lbs (not including the person) and our person is 155lbs.
2500lbs / 155lbs = 16.1
The car is moving the same amount of weight as 16 people. Now, you might say “but a lot of that car weight is the engine itself…” True, but the same is true for the human, no? So lets keep going a moment. Let see how many cpm per pound we’re using.
Car: 1000cpm / 2500 = 0.40 calories per mile per pound…
Human: 112.6 / 155 = 0.73 calories per mile per pound…
Assuming a car speed of around 60mph, that means a human uses almost twice as many calories per pound to move at 1/6th the speed of the car. That is assuming no extra load for either. Toss in another person or two and a couple of hundred pounds of gear, what do you think is the best way for you and your mates to travel over long distance?
Now that I’ve blogged in support of the automobile, I’d like to say that I’m not a big fan of America’s addiction to cars. I’d like to see better use of trains, actually. However, pretty pieces of art showing calorie use compared is kind of a load of crap. Speaking of crap, I wonder what kind of numbers you would get if you compared the emissions per calorie consumed for a car versus a human? Ewww….