746 watts per Horsepower outdated
written by free energy now , April 18, 2007
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.
I thought you'd like that one, Rob.
But if we increase the number of kilometres per mile, then won't the number oof miles per kilometre decrease as a result? That won't be good, and we'll need additional TECHNOLOGY!!! to change the rules of logic so that both km/miles and miles/km can increase together.
[insert usual tripe about Galileo here]
-- bi
To maximize fuel efficiency, I've found it's best always to assure that my destination is at a lower elevation than my departure point and that the wind is at my back.
Logic and technology will get us through this.
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!
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.
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?
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?
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.
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.
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!
;)
"Car BTU per vehicle mile"
All these newfangled units do my head in :-)
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