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How to Charge Your Cellphone Using Wasted Heat
Ilya writes "Companies such as BMW are investing in Thermoelectric Generators to make their cars more efficient by replacing the alternator. Thermoelectric Generators convert wasted heat from the engine into electrical power. This green instructable shows how you can use the same technology right now at home to harvest expelled heat from home appliances to charge your cellphone and other gadgets. Also features a lego racer powered by the roaring flames of a tea candle."
BWM makes awesome cars
I like to work out in my rec. room with various exercise equipment. My favorite? The Carnot cycle (http://en.wikipedia.org/wiki/Carnot_heat_engine)
I just hop on and convert all the waste heat in the room to useful energy
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I could probably power a small village :-)
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Given that the average American consumes 13,500KWh per year, getting a couple of Watt-hours into your phone from wasted heat instead of the grid isn't going to make a damn bit of difference.
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finally someone invents a use for the formerly useless lego mindstorms thermal sensor. Use it to let your mindstorms bot find a recharging stations
Some drink at the fountain of knowledge. Others just gargle.
laptop heat? can that be used to charge it self?
Seriously: major typo in the summary, folks.
Many years ago, I worked with an ad exec who had (much previously) pitched a campaign to BMW. His agency lost the bid to another agency, even though they thought they had an innovative ad concept. Some months later, he was reviewing the posters and realized they had printed "BWM" in multiple places, in very large type, and nobody at the agency had noticed prior to the presentation. Ooops.
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This is something I never quite grasped from physical chemistry class. Obviously you can reclaim some energy from heat, but you can't reclaim it all, as that would break the 3rd law of thermodynamics. How much energy can you actually reclaim from a given amount of heat? Is it a constant fraction, if so where does that number come from? Is it variable? If so, what does that number depend on?
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No. See the laws of thermodynamics.
If the geiger counter does not click, the coffee, she is not thick.
That would be the second law, that would be broken if you could recover all the heat. The third law is a bit more obscure and basically means that the first two laws apply to everything.
The amount you can recover varies according to the efficiency of the device you use to recover it, and depends completely on the details of your setup. Obviously no device is 100% efficient (that's the second law again), so you will never be able to recover all of the lost heat. It is possible to get remarkably high efficiency in some setups.
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That heat is traditionally used for roasting nuts
AT&ROFLMAO
but you will get longer life out of it then?
You already have to use a radiator to get rid of the heat so you might as well do something useful with it.
I guess farts are funny anymore.
Having to work for a living is the root of all evil.
Yes, you will get longer battery life if you turn some of the "heat" into electricity. There are some problems to look out for, though. The thermocouples don't really convert heat into electricity. It's the temperature difference between the hot and the cold side which creates the electricity, so you have to have a heat source and a heat-sink capable of sinking the heat without warming up too much. Since the cool side has to stay cool, the temperature difference between the air and the heat-sink is low, which means you need a much bigger heat-sink than normally. (The instructable shows a thermocouple with heat sink mounted on the side of a bike exhaust: the additional drag probably costs more energy than the device can extract from the heat difference...)
Haha, good one. How about this? Leftist terrorists were discovered - their plot was to dress as police and then open fire, but they spelled police wrong on their motorbikes, and were arrested when real cops spotted the mistake.
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"It was the G1-1.4-219-1.14 $75 from tellurex."
Using "waste" sure is expensive...
I was visiting Illinois State University's physics department because I am planning on attending this fall. They were working on a material along these lines with a fairly high efficiency rate but they were just starting actually trying to make small amounts of the material.
Their intended use of the material would be in steel foundries, etc. where millions of dollars are spent on power and even something not very efficient could save a ton of money.
From what I gathered talking to the professor there the same efficiency increasing techniques could be used even with smaller temperature differentials as long as you had different materials used.
Sorry but they don't have too much information on their website. They had a few posters with information in the building but not much online.
http://www.phy.ilstu.edu/programs/research.html
A link to the professors bio:
http://www.phy.ilstu.edu/facandstaff/marx.html
Keep the hot side hot and the cool side cool... don't tell me McDonalds had the secret to providing a minuscule increase in energy efficiency and only used it to make a crappy burger!
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I wanna use my huge bank of toasty little wall warts to charge my cell phone. If I can do that the lazy little power-sucking tribbles might finally justify their existence.
Peltier Junctions are really old news, they're not very efficient at all, they don't last forever, and they're not particularly cheap. TFA doesn't have anything new to say or any links that have anything new to say. Mod the entire post down to -1, Useless post and move on.
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You should get in touch with the GP, Bill Winston Ministries may be interested in helping your friend clear some of those old BWM posters out of his warehouse. I'm assuming, of course, that Bill Winston might think it a nifty idea to sell his "Ministries" by proudly featuring fancy cars.
I have a secret plan to run ipods off of the Cosmic microwave background radiation.