Progress Marches On

Economists and politicians are often found putting more faith in technical progress than actually technically adept people do. Hope springs eternal. It’s a shame to neglect the possible role of technical progress in getting us out of our difficulties. Perhaps we should be rethinking our pessimism.

I was trying to track down the power consumption of a typical car in watt-hours per mile (this is oddly hard to do) when I came across this particularly striking example of techno-optimism in comments here. See what you think of it:

746 watts per Horsepower outdated
written by free energy now , April 18, 2007
Your comments in compairing the car to cold fusion means that you’re assuming that technology can’t change the 746w/hp. Is it at all possible that the cars engines are more efficient then your calculations allow for. There are also ways of using capacitors to increase efficiency in heavy load conditions. Technology is changing my friend, and in a lot of situations the nubers just don’t add up. My friend has designed a heater which can run indefinitly after a couple of days of being pluged in. He heats his whole house with them, no they don’t use cold fusion, just an ingenious design. So just because you can’t figure out the math, doesn’t mean it’s immposible. Peace out

That’s the way to do it. Now we’re really talking progress!


  1. Yes, some of the light escapes through windows (either directly or through multiple reflections inside) and thus is not changed to heat.This is especially bad with compact fluorescent light bulbs which produce a large amount of light energy compared to heat energy!;)

  2. I have to say (in a quibbling fashion) that converting electricity to heat isn't 100% efficient. Even at relatively low temperatures, some tiny amount of energy is radiated in wavelengths not producing heat. Even when converting everything to waste heat we can't quite break even.I doubt that this is the hurdle that has been overcome by "free energy now's" friend, however.

  3. True, actually. Now that I am in a hot climate I am trying harder to train myself to turn unnecessary lights off. It is a much bigger waste in air conditioning season than in heating season. Under any conditions where you actually use an electric heater you actually should run all your lights, TV, stereo, whatever electric devices you can get any utility out of. In Quebec where electricity is as cheap as and (being mostly hydro and nukes) cleaner than home heating fuel one should turn off as few lights as possible during the winter.

  4. OK, another electric efficiency idea: any electric power that doesn't go to its primary use ends up as heat. So 15 100W bulbs are as efficient as a 1500W electric heater; plus they make light! If we could get electric heaters that also do something useful (but not terribly efficient) then in some sense we'd make the underlying process nearly 100% efficient. Electrolysis? Home aluminum smelting?

  5. Nice resource, Ian. Thanks!My guess of a KW-hr per mile was in the right ballpark. So an evening of watching my big screen 300W TV is about the equivalent of driving a mile in a small car. I feel better about the TV. Worse about the car, though.Nice point about electric heaters, too. Electricity is the perfect heating fuel because it is 100% efficient, right?

  6. Ingenious design of an electric heater? Ha! You can't improve on 100% efficiency! Though if you had a heat sink and you were aware of variable electric rates, you could essentially store the spare electrical energy from the night and release it during the day.I think the data you want is here (if you want empirical data, not optimal numbers). Car BTU per vehicle mile is 5514 (1600 watt-hours per mile), and per passenger mile is 3512 BTU.

  7. Well, in the end nobody gets out of here alive. So there's really no winning and no losing.I think it would be good if civilization lasted for a good while longer. There's little telling where the best place to put our efforts are toward that end. I am willing to bet that getting more watts per hp (or is it the other way round?) is not the most productive effort we can make. On the other hand, I guess if you think about it, it's not the least productive either!

  8. Thanks Michael, it goes without saying (though I'm saying it) that that will end up in my semi-regular "A cornucopia of cluelessness" posts.If we finally converted to SI units and then, through technology, changed the number of kilometers/mile, we'd be able to go much farther on a gallon of gasoline. Changing the number of liters/gallon would help even more.

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