Tuesday, April 29, 2008

Efficiency

I was watching Car of the Future on PBS (in HD, of course) and this struck me. Internal combustion engines run at an average efficiency of about 20% (compared to theoretical Carnot limits). Add to that the fact that we get into a 2,000 pound machine to move a 150lb human. Let's make the math easier and say we weigh 200lbs. If it takes 1 gallon of gas to move just a 200lb human at 100% efficiency x meters, it takes (2000/200)*(100/20) = 50 gallons to move 2,000lbs at 20% efficiency the same distance.

50X more resources than needed.

Meanwhile, a minister led a pray-in at a Chevron in San Francisco asking God for lower gas prices. We shouldn't be campaigning (or praying) for lower gas prices—we should be demanding better fuel economy and smarter means of transportation.

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