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How to Charge Your Cellphone Using Wasted Heat

ScuttleMonkey posted more than 4 years ago | from the diy-and-try-not-to-burn-the-house-down dept.

Hardware Hacking 214

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."

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214 comments

BWM? (1, Informative)

brian0918 (638904) | more than 4 years ago | (#27652283)

Bill Winston Ministries?

Re:BWM? (5, Interesting)

Anonymusing (1450747) | more than 4 years ago | (#27652523)

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.

Re:BWM? (0)

Anonymous Coward | more than 4 years ago | (#27653027)

Heh, my job classification is a "Bandwidth Manager." Not quite BMW though

HEY SCUTTLEMONKEY! SUCK MY MONKEY NUTS (-1, Troll)

Anonymous Coward | more than 4 years ago | (#27652869)

Almost as bad as KDAWSON at not reviewing submissions, eh? Suck them.

BWM makes awesome cars (2, Funny)

Anonymous Coward | more than 4 years ago | (#27652285)

BWM makes awesome cars

Re:BWM makes awesome cars (5, Funny)

Hognoxious (631665) | more than 4 years ago | (#27652527)

I prefer Adui. You can't beat their Quartto transmission on a wet road.

Re:BWM makes awesome cars (1)

Skyshadow (508) | more than 4 years ago | (#27652695)

Nor can you beat the cost of replacement once the thing goes.

Re:BWM makes awesome cars (1)

Gnavpot (708731) | more than 4 years ago | (#27653241)

Nor can you beat the cost of replacement once the thing goes.

Correct. Quartto transmissions are incredibly rare. But you could try using a Quattro transmission as a replacement

I charge my cellphone while riding my Carnot cycle (5, Funny)

thomasdz (178114) | more than 4 years ago | (#27652315)

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

Re:I charge my cellphone while riding my Carnot cy (1)

TerranFury (726743) | more than 4 years ago | (#27653067)

I just hop on and convert all the waste heat in the room to useful energy

If you're doing exercise, it'd be a Carnot heat pump, n'est-ce pas? One end would get cold, and the other hot...

Wish I could harvest the power from my farts..... (2, Funny)

Finallyjoined!!! (1158431) | more than 4 years ago | (#27652321)

I could probably power a small village :-)

Re:Wish I could harvest the power from my farts... (4, Funny)

d474 (695126) | more than 4 years ago | (#27652369)

Did you customize that sig to your comment, or should you go see a doctor about your explosive flatulence problem?

Sipping From a Firehose (4, Informative)

lobiusmoop (305328) | more than 4 years ago | (#27652403)

Given that the average American consumes 13,500KWh per year [nationmaster.com], 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.

Re:Sipping From a Firehose (1, Insightful)

palegray.net (1195047) | more than 4 years ago | (#27652511)

Everything starts somewhere.

Re:Sipping From a Firehose (5, Insightful)

Toonol (1057698) | more than 4 years ago | (#27652633)

It's vastly more efficient, and probably less expensive, to redesign the Dryer/Air Conditioner/whatever to waste less heat in the first place. So I'm not really disagreeing with you, but I feel that it's a bit more of a feel good effort than an actual relevant solution.

Re:Sipping From a Firehose (5, Funny)

chromas (1085949) | more than 4 years ago | (#27652965)

I used to have neighbors who would leave their air conditioners running all day, then, when they came home, they'd let the doors hang open for a while to let some warm in. Less stupid people could help, too.

Re:Sipping From a Firehose (2, Funny)

camperdave (969942) | more than 4 years ago | (#27652995)

Why do air conditioners not come with clocks, so they can be set to be on at specific times?

Re:Sipping From a Firehose (1)

afidel (530433) | more than 4 years ago | (#27653107)

$20 thermostats ARE programmable and pay for themselves in the first month or two, people are just too lazy to use them.

Re:Sipping From a Firehose (1)

silas_moeckel (234313) | more than 4 years ago | (#27653417)

Because that costs a couple extra cents per unit and causes people to call in because they can not set there clock or return them to stores because they are two complicated. Same logic as to why they still sell microwaves with just a dial. People are generally stupid and making a commercial product requires it to be idiot proof.

Re:Sipping From a Firehose (2, Interesting)

PitaBred (632671) | more than 4 years ago | (#27653547)

Some do. Actually, some of them even come with these nifty "thermostats" where you can have them come on only when it gets too hot. And if you look even more, you can find a thermostat coupled with a clock so you can set it to different temperatures at different times! Technology really is amazing.

Re:Sipping From a Firehose (1)

PitaBred (632671) | more than 4 years ago | (#27653587)

Fewer [reference.com] and less [reference.com] mean similar but very distinct things. Precision in language really helps people take you more seriously.

Re:Sipping From a Firehose (4, Insightful)

Rich0 (548339) | more than 4 years ago | (#27653603)

Additionally, such waste heat might not actually be "free" - depending on some of the implementation details.

The engine works by generating heat and then converting it to mechanical motion while dissipating that heat to a cold sink. If you don't "waste" that heat by sending it to a cold sink then the engine operates less efficiently.

Again, it depends on the details - the energy might be "free," or it might just rob the engine of power just as an alternator does. You can't get around the laws of thermodynamics, though...

Re:Sipping From a Firehose (0)

Anonymous Coward | more than 4 years ago | (#27652587)

Very true, assuming you'll only have one person sipping off that firehose. Even small things like this can make a huge difference.

Re:Sipping From a Firehose (3, Insightful)

Anonymous Coward | more than 4 years ago | (#27652661)

Yes, since we can't solve the problem in one step, we should never proceed

To restate your premise:

Given that the average American drives 8500 miles per year, spending one day a month bicycling to work isn't going to make a damn bit of difference.

Re:Sipping From a Firehose (1)

afidel (530433) | more than 4 years ago | (#27653083)

How about running the AC and all onboard electronics and going to electric power steering, that would probably increase efficiency by ~10%, the equivilant of pulling millions of vehicles off the road if done industry wide (electric power assist is already moving down market due to being an easy fuel efficiency gain).

Re:Sipping From a Firehose (1)

Gordonjcp (186804) | more than 4 years ago | (#27653213)

and going to electric power steering

Why would electric power steering help? If you've got enough torque to run an alternator, you've got enough torque to run a hydraulic pump.

Re:Sipping From a Firehose (1)

afidel (530433) | more than 4 years ago | (#27653359)

I think it has to do with the fact that you increase friction full time for something that is used some small percentage of the time.

Re:Sipping From a Firehose (1)

Capt.DrumkenBum (1173011) | more than 4 years ago | (#27653361)

The fact is that power steering is only useful at low speed.
It is easier to switch on and off an electric system than a mechanical/hydraulic system.

Re:Sipping From a Firehose (1)

bmwm3nut (556681) | more than 4 years ago | (#27653369)

The hydraulic pump is running all the time, even if you're not turning. It's much more efficient to have the electric power steering (which is much easier to make variable assistance too) only kick in when you need to turn.

Re:Sipping From a Firehose (1)

maxume (22995) | more than 4 years ago | (#27653087)

Those figures are per capita and include industrial and commercial consumption (a society sets the rules for industry and commerce and is responsible for their behavior, but it isn't as if the average American is sitting at home finding news ways to waste electricity, some clever sole is out there doing it for them, lighting a parking lot or whatever).

Re:Sipping From a Firehose (1)

FailedTheTuringTest (937776) | more than 4 years ago | (#27653183)

One person clapping in an audience of 2,000 doesn't make a damn bit of difference. So why do you bother to clap?

Re:Sipping From a Firehose (0)

Anonymous Coward | more than 4 years ago | (#27653459)

I sure don't, saves me energy.

Re:Sipping From a Firehose (1)

maharb (1534501) | more than 4 years ago | (#27653597)

Yes but clapping also doesn't compare well with this. Clapping is "free". This setup cost $100+ in parts to charge a cell phone and that is assuming you have a heat source to use to keep your phone charged all the time. I have not done the calculations but I am not quite sure this pays off. Plus putting these things on anything moving can't be efficient. You are adding tons of weight(requires a heatsink) to a vehicle in order to save energy?

Re:Sipping From a Firehose (1)

dontmakemethink (1186169) | more than 4 years ago | (#27653265)

Most "eco-friendly" energy sources in fact either cause the same amount of pollution per energy unit or often more, such as biodiesel, ethanol, geothermal, and most wind farms barely break even after huge investment and CO2 emmissions from building them. Solar-thermal is the best renewable source for truly beneficial energy production (except for hydro-turbine of course). All other eco-friendly power projects are just political boondoggles.

In case you're wondering - boondoogle: a project funded by a government body that is of no real value to the community, done merely to appear productive.

At last! (4, Funny)

goombah99 (560566) | more than 4 years ago | (#27652439)

finally someone invents a use for the formerly useless lego mindstorms thermal sensor. Use it to let your mindstorms bot find a recharging stations

but is it cost effective? (2, Insightful)

DomNF15 (1529309) | more than 4 years ago | (#27652455)

I read the article in Car & Driver the O.P. is referring to a while ago (if it's not already obvious the automotive company he is referring to is BMW). At least in automotive applications, it begs the question, is it worth the effort? The extra parts, weight, and cost you'd have to add to a vehicle would probably cause you to break even in terms of MPG or dollars per gallon. The situation is similar with diesel engine options, the extra initial cost of the diesel optioned vehicle is often times just not worth it, despite the MPG advantage.

Re:but is it cost effective? (1)

edittard (805475) | more than 4 years ago | (#27652591)

At least in automotive applications, it begs the question, is it worth the effort?

Let me assure you that in grammatical application it does nothing of the kind.

laptop heat? can that be used to charge it self? (3, Funny)

Joe The Dragon (967727) | more than 4 years ago | (#27652473)

laptop heat? can that be used to charge it self?

Re:laptop heat? can that be used to charge it self (1)

palegray.net (1195047) | more than 4 years ago | (#27652529)

Yes, but your battery will still go dead.

Re:laptop heat? can that be used to charge it self (2, Interesting)

Joe The Dragon (967727) | more than 4 years ago | (#27652863)

but you will get longer life out of it then?

Re:laptop heat? can that be used to charge it self (1)

maxume (22995) | more than 4 years ago | (#27653133)

Only if you run your computations in reverse some of the time.

Re:laptop heat? can that be used to charge it self (3, Interesting)

Anonymous Coward | more than 4 years ago | (#27653297)

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...)

Re:laptop heat? can that be used to charge it self (2, Funny)

geobeck (924637) | more than 4 years ago | (#27653649)

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! [wikipedia.org]

Re:laptop heat? can that be used to charge it self (4, Funny)

Linker3000 (626634) | more than 4 years ago | (#27652801)

That heat is traditionally used for roasting nuts

Re:laptop heat? can that be used to charge it self (0)

Anonymous Coward | more than 4 years ago | (#27652909)

I see you got a Lenovo T60 too!!!

Re:laptop heat? can that be used to charge it self (0)

Anonymous Coward | more than 4 years ago | (#27653109)

Sony had a pretty efficient line of nut-roasting batteries but too many people returned them because most people want their salted, too.

Re:laptop heat? can that be used to charge it self (0)

Anonymous Coward | more than 4 years ago | (#27652811)

Dunno about you, but my laptop uses regenerative breaking. Works well enough, but it's a real pain in the ass jogging behind the sucker.

Re:laptop heat? can that be used to charge it self (1)

cbiltcliffe (186293) | more than 4 years ago | (#27653185)

Regenerative breaking?

Does that mean hitting it with a sledgehammer recharges the battery?

Re:laptop heat? can that be used to charge it self (0)

Anonymous Coward | more than 4 years ago | (#27653619)

A Welsh phrase comes to mind: 'Malu glo man yn gnapiau' - smashing fine (small) coal into lumps. Now that's the kind of regenerative breaking that'll actually power your laptop!

Re:laptop heat? can that be used to charge it self (1)

Spyder0101 (1485837) | more than 4 years ago | (#27652905)

Some of the energy can be recovered, but not enough to charge the battery.

Re:laptop heat? can that be used to charge it self (1)

Cedric Tsui (890887) | more than 4 years ago | (#27653583)

It's also worth noting that these heat-to-electricity units impede the flow of heat. Just like putting a dam with a turbine in it makes the water levels upstream go up, a peltier style generator would increase your laptop's temperature.

Hopefully, the generator will provide the extra energy needed to power all the extra fans you'll need.

iPhone (1)

xpuppykickerx (1290760) | more than 4 years ago | (#27652495)

Great! Something to finally help the terrible battery life on my 3G.

Re:iPhone (0)

Anonymous Coward | more than 4 years ago | (#27653283)

Hey, go back to your 2G and wait minutes for each page load. I'll take the faster option with less battery, thank you.

Thermodynamics (2, Interesting)

Hatta (162192) | more than 4 years ago | (#27652567)

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?

Re:Thermodynamics (2, Informative)

edittard (805475) | more than 4 years ago | (#27652647)

It depends on the temperature difference between the heat source and the heat sink; the higher the difference, the more efficient the conversion.

P.S. Ever heard of google?

Re:Thermodynamics (4, Insightful)

jabithew (1340853) | more than 4 years ago | (#27653659)

P.S. Ever heard of google?

Please, it's a fairly esoteric piece of knowledge and this is as good a forum to ask it in as any. A bit of civility wouldn't kill you.

Re:Thermodynamics (1)

CSMatt (1175471) | more than 4 years ago | (#27652675)

Third law? I thought it was the second law of thermodynamics that says that not all heat can be converted back into energy.

Re:Thermodynamics (1)

HTH NE1 (675604) | more than 4 years ago | (#27653073)

At least it's easier than constantly muttering block transfer computations into charged vacuum emboitments to hold back the inevitable heat death of the universe.

Re:Thermodynamics (2, Informative)

mmontour (2208) | more than 4 years ago | (#27652677)

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?

http://en.wikipedia.org/wiki/Carnot_cycle [wikipedia.org]

For each unit of heat energy, the maximum amount of work (useful energy extracted) is (1 - Tc/Th), where Tc and Th are the temperatures of the cold and hot side of the process.

Re:Thermodynamics (1)

Toonol (1057698) | more than 4 years ago | (#27652703)

For some reason, I vaguely remember that the efficiency of extracting energy from heat is proportional to some power (4th?) of the relative difference in temperature between the object and its surroundings. As a practical matter, I think energy is generally reclaimed by using variations on the mechanical work expansion/contraction performs when temperature changes.

I'm sure somebody will come by in a few minutes to prove me wrong about everything I said.

"In this house, young lady... (2, Informative)

freejung (624389) | more than 4 years ago | (#27652733)

we obey the laws of Thermodynamics!" -- Homer Simpson

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.

Re:"In this house, young lady... (0)

Anonymous Coward | more than 4 years ago | (#27652809)

If I remember my physics correctly, to reach 100% efficiency, one would need to reach absolute zero with absolutely no energy expenditure.

Re:Thermodynamics (5, Funny)

AnotherBlackHat (265897) | more than 4 years ago | (#27652787)

Obviously you can reclaim some energy from heat, but you can't reclaim it all, as that would break the 3rd law of thermodynamics.

That's the 2nd law, not 3rd.

1st law - You can't win.
2nd law - You can't even tie.
3rd law - You can't get out of the game.

Re:Thermodynamics (3, Interesting)

TerranFury (726743) | more than 4 years ago | (#27652919)

As other posters have mentioned the physical limit you're concerned with is the Carnot efficiency.

One view of things not yet mentioned by posters is that energy is not what matters but exergy -- the capacity to do work. A bathtub full of lukewarm water contains a great deal of energy, but little exergy. In general, electrical and mechanical energy has a lot of exergy; thermal energy is as low-exergy as you can get, especially at low temperatures.

Note that the above is really just a rephrasing of the idea of entropy.

Re:Thermodynamics (1)

vlm (69642) | more than 4 years ago | (#27653085)

Another point not mentioned is the economics of the situation.
Inherently the home device is going to raise the temperature of the appliance.
Higher temp appliance means it wears out faster.
Wears out faster means lots of energy spent on replacement.
So, at first glance, what has been designed is a way to save cents of electricity at a cost of dollars of repair work.

I don't think the car makers will like replacing an alternator with thermoelectrics, because they are immensely big and heavy for the power required compared to an alternator, and they don't wear out as fast meaning less repair income.

The Matrix is right! (0)

Anonymous Coward | more than 4 years ago | (#27652671)

Once our electronic devices realize they can use us as a replacement for a Duracell battery, Zion is lost!

Is "Waste" Heat Really Free Energy? (1)

CodeBuster (516420) | more than 4 years ago | (#27652755)

While my own knowledge of thermodynamics is minimal to say the least (never really studied physics at university, got stuck deep in comp sci instead), I seem to remember something about heat tapping generators reducing the thermodynamic efficiency of an internal combustion engine. If an additional load is introduced on an internal combustion engine, whether that be a direct load such as an extra belt on the output shaft to run the alternator or an indirect one such as a "waste" heat conversion alternator, then wouldn't that also reduce the output power of the engine (necessary in the case of the alternator since gasoline engines will not run without one)? Perhaps I am missing something that a physics geek could easily explain or is there really a "free lunch" here with regard to waste heat?

Re:Is "Waste" Heat Really Free Energy? (1)

eepok (545733) | more than 4 years ago | (#27653015)

It's not "wasted" energy until we refrain from harnessing it. It's not free since we paid for it (by using the product that creates heat as a by-product).

What this is like, is the "5-second rule". This is scooping up perfectly edible M&Ms off the floor before they rot or the dog gets to it. This heat that is a by-product of reaction is still energy, so it's great that we have a way to pick it up and use it before it dissipates.

In the end, since we still want to eat M&Ms, we can reduce the overall number of bags bought in the year by making sure we eat as many of the dropped M&Ms as possible before the house pooch comes by and snatches them.

Re:Is "Waste" Heat Really Free Energy? (1)

TerranFury (726743) | more than 4 years ago | (#27653021)

There's no free lunch unless the food was going into the dumpster anyway. Practical engines throw away tons of heat. Heck, that's what your radiator is explicitly for. So since heat is leaking out of your engine at a prodigious rate anyway, you might as well use that flow to power another heat engine (a thermocouple in this case, I guess).

Re:Is "Waste" Heat Really Free Energy? (1)

Rabbitbunny (1202531) | more than 4 years ago | (#27653043)

cars have radiators for a reason. simply downsize/cover the radiator and the waste heat increases to a usable level.

Re:Is "Waste" Heat Really Free Energy? (1)

multipartmixed (163409) | more than 4 years ago | (#27653351)

> cars have radiators for a reason. simply downsize/cover the radiator and the
> waste heat increases to a usable level.

Cars have thermostats for a reason, too. It's so you don't have to cover the radiator to get the engine temp up. ;)

Re:Is "Waste" Heat Really Free Energy? (1)

zippthorne (748122) | more than 4 years ago | (#27653489)

So, you're going to cripple a 35 kW heat engine to make a 4 W heat engine more efficient?

Re:Is "Waste" Heat Really Free Energy? (1)

bored_engineer (951004) | more than 4 years ago | (#27653231)

If you reduce the temperature between the phases of the cycle, then the efficiency will go down. (In the ubiquitous Wikipedia article [wikipedia.org], that would be the difference between Th and Tc. In the case of every heat engine, some of that heat is going to necessarily go to waste. Your car has a big radiator out front to handle this waste heat. (Just for giggles, here's another Wikipedia article [wikipedia.org] about the Otto cycle.)

The little doodads they suggest in the article use heat that would have just gone away to the environment anyhow. The trouble with peltiers is that they have (or at least used to) have a fairly high $/watt up-front cost. The little buggers, in my opinion, are too expensive to bother.

Now for my question: Did the folks who made the silly devices find out how much energy is invested into building the peltier units and compare that to the electricity (or fuel) saved?

Re:Is "Waste" Heat Really Free Energy? (1)

cbiltcliffe (186293) | more than 4 years ago | (#27653291)

If you're taking heat away before said heat moves the piston down, then yes, you're reducing the efficiency, and therefore power output.

If you're taking heat out of the upper radiator hose, or the exhaust pipe, both of which are just dumped out to the atmosphere, anyway, then it really is waste heat, and you're not reducing the efficiency of anything.
Recover enough heat, and you might be able to do with a smaller radiator and cooling fan, though, which, while it wouldn't increase the efficiency of the engine, it would reduce both the engine load for cooling, and the weight of the car slightly, so have the same effect as an increase in power.

Re:Is "Waste" Heat Really Free Energy? (1)

Cedric Tsui (890887) | more than 4 years ago | (#27653745)

Yes.
There's a post above about the carnot cycle which is theoretically the most efficient engine for turning heat into useful energy. The carnot cycle efficiency is equal to 1-Tc/Th

Basically, the hotter your furnace and the colder your exhaust, the more efficient your system is. So if you have some powerplant's waste heat, it's not useful to you unless you have some reservoir of cold to dump that heat into while running your cycle. Obviously, it is more efficient to apply that cold reservoir to the original powerplant rather than building a separate cycle.

However. With a car, your exhaust temperature is almost completely controlled by the volume ratio of the engine cylinders. So the excess heat, and the difference in the temperature of the coolant and the air around the car is free for the taking. Just like the regenerative brakes used in hybrid cars harvest free energy.

Wasted heat? (1)

Turzyx (1462339) | more than 4 years ago | (#27652911)

Surely the primary objective of a combustion engine is to provide a means of propulsion, not heat generation?

Perhaps I'm missing something?

Re:Wasted heat? (2, Informative)

h4rr4r (612664) | more than 4 years ago | (#27653041)

You already have to use a radiator to get rid of the heat so you might as well do something useful with it.

Re:Wasted heat? (1)

maxume (22995) | more than 4 years ago | (#27653247)

The heat is an unavoidable secondary effect (of an internal combustion engine). If you have a device than can extract electrical energy from the heat without interfering with proper cooling, the energy is essentially free.

Re:Wasted heat? (1)

afidel (530433) | more than 4 years ago | (#27653319)

Most internal combustion engines average 18-20% thermal efficiency (that is only about 18-20% of produced BTU's are available mechanically). System efficiency is even lower due to friction in all the components between the engine and where work is done.

Power my computer! (1)

Myrcutio (1006333) | more than 4 years ago | (#27653011)

If only we could come up with some sort of mineral oil solution to absorb my body heat, i could power my computer from the heat my body generates! I could even get my neighbors to join in and we could pool our bodyheat to power a super computer. And maybe to relieve boredom we could all play in a "virtual world" so that we don't waste our energy on non-supercomputer related activities. Maybe the Matrix Online would be a good choice.

Power gain or loss? (1)

ACMENEWSLLC (940904) | more than 4 years ago | (#27653017)

How much energy is produced? I'd imagine not a lot. How much does it weigh? Does it cost more in fuel to lug these around than they can produce? You'd need one at the exhaust, one at the engine, one at the brakes..

Is this another deal where I spend $1000 and get 5w/hour?

good bar trick too (0)

Anonymous Coward | more than 4 years ago | (#27653125)

cell phone died but need a number? rub the battery between your hands quickly for about 30 seconds. it'll give your phone enough charge to load the contact list and jot down the number of the chick that stood you up. who needs BWM to come up with this "technology" stuff, i've been doing it for years.

Madness! (0)

Anonymous Coward | more than 4 years ago | (#27653273)

What's with all this "environment awareness" crap! God created all cars the way they are. Cars are meant to give off heat! Cars are MANLY. What kind of wussy car uses "environment friendly" ways and whatnot. What's next, telling us to "conserve energy" to "save the planet"?! Hah! Now if you'll excuse me I gotta get back to my Dodge truck!

Regards,
An Angry Texan.

Microvolt thermostat (0)

Anonymous Coward | more than 4 years ago | (#27653307)

I just want to comment that at one time my house had a microvolt thermostat. The power to run the thermostat came from the heat generated by the pilot light of the gas furnace. The advantage of this is that if the power went out, the heat could still turn on.

When I upgraded to an energy efficient heating system (with no pilot light) this was replaced.

one acronym (1)

WindBourne (631190) | more than 4 years ago | (#27653331)

JTEC [johnsonems.com]. Use this, drop the alternator as well as the serpentine belt and move towards an all electric system. This would allow them to move a GAS car to an electric powered steering (or perhaps a motor driving hydraulic pump), a heatpump that would also go into an electric car. This would allow a car company to more easily move towards electric cars.

$75 for an ipod charger? (2, Funny)

billybob_jcv (967047) | more than 4 years ago | (#27653415)

"It was the G1-1.4-219-1.14 $75 from tellurex."
Using "waste" sure is expensive...

Re:$75 for an ipod charger? (0)

Anonymous Coward | more than 4 years ago | (#27653545)

It might seem expensive if you don't use an iphone, but when you look to change the battery...

Saw research into much larger scale uses of this (2, Interesting)

Jared555 (874152) | more than 4 years ago | (#27653427)

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 [ilstu.edu]

A link to the professors bio:
http://www.phy.ilstu.edu/facandstaff/marx.html [ilstu.edu]

Re:Saw research into much larger scale uses of thi (1)

Jared555 (874152) | more than 4 years ago | (#27653435)

I THINK they said the calculated efficiencies would be along the lines of 15-25% depending on materials, temperature differentials, and the actual temperatures. It may have been higher than that though.

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