Body Heat Energy Generation

BuzzSkyline writes "Researchers in Belgium have developed devices to harvest the waste heat our bodies throw off in order to convert it to electricity to run devices such as a wristband blood oxygen sensor and an electrocardiogram shirt. As a side benefit, the power sources help cool you down and keep you looking cool, all while running sundry micropower devices. In fact, the researchers mention that the energy harvesting head band works so well that it can get uncomfortably cold. In that case, they say, 'This problem is solved in exactly the same way as someone solves it on the body level in cold weather: a headgear should be worn on top of the system to limit the heat flow and make it comfortable.' But it would be such a shame to cover up the golden heat-harvesting headband with a hat."

Comments

Truely Fremen fashion

[gzipped_tar]

What's next? A body-movement powered (or better, heat & movement hybrid power), fully functional stillsuit?

Re:Truely Fremen fashion

[Forge]

You do if you want to drink the water expelled in your pee and sweat without any of those pesky toxins.

As for me, electricity costs are getting so high that a human sized hamster wheel attached to a basic generator coil looks really attractive right now. Additional benefits like exercise and looking cool on that thing should clinch the deal.

Re:Truely Fremen fashion

[camperdave]

As for me, electricity costs are getting so high that a human sized hamster wheel attached to a basic generator coil looks really attractive right now.

Of course, the problems involved in acquiring and caring for a human sized hamster tend to outweigh the benefits.

Re:Truely Fremen fashion

[supernova_hq]

Dean Richmond will also contest that they are DANGEROUS!

Re:Truely Fremen fashion

[davester666]

As a bonus, it could help power your strength-enhancing exo-skeleton!

Re:Truely Fremen fashion

[couchslug]

"What's next? A body-movement powered (or better, heat & movement hybrid power), fully functional stillsuit? "

This could prove useful in the US.
A heat-powered liposuction pump could harvest fat to be pyrolized into lipo-diesel, ensuring a limitless supply of fuel for our SUVs.

An accumulator bladder could be worn off-vehicle, with a quick QD on the seatbelt to harvest each each time the vehicle is driven. Passenger connections and harvester plumbing on children's car seats would ensure efficient collection.

Re:Truely Fremen fashion

[Forge]

I disagree. The Human Sized Hamsters I have right now are quite harmless as long as the wheel is kept oiled and the food tray loaded.

Re:Truely Fremen fashion

[Sulphur]

Or your exo-skeleton could power a generator using more motion than a bicycle.

--

We are so poor that we cannot afford a language. Mel Brooks

Re:Truely Fremen fashion

[supernova_hq]

And for the love of god, never hide under a fur coat!

There is no spoon.

[TravisHein]

Great, now in the future when robots and machines rule the earth, they can use this to harvest energy from all of us, just like the Matrix.

Re:There is no spoon.

[sakdoctor]

Thanks to the laws of physics, they will only be micro-power overlords.
Though perhaps they won't need massive amounts of force to subdue humanity; from what I've seen, most people would choose the blue pill.

Re:There is no spoon.

[jggimi]

Or the woman in the red dress. :)

Re:There is no spoon.

[iamapizza]

I think it's all a steaming pile of crap. Get it? waste. heat. Oh, I slay myself.

Re:There is no spoon.

[Gilmoure]

I, for one, welcome our Micronaut body-heat harvesting overlords.

Screw that

[elrous0]

You're wasting the real potential of this thing. I live in an area that gets hot as hell in the summer. If it really does get "uncomfortably cold," I'd pay good money for a whole suit made of the stuff.

Re:Screw that

[dintech]

Good idea and hurry the hell up with that next shipment of Spice.

Re:Screw that

[Thelasko]

Unfortunately, the summary and the Physics Buzz article grossly misrepresent the research being done here. The device only becomes "uncomfortably cold" when ambient temperatures are below what are considered comfortable by most people. The AIP article also notes that it is unlikely that this device will ever be able to harvest enough energy to power current portable devices. They instead suggest that future devices be designed around the power output of this device.

Re:Screw that

[StikyPad]

Right, that's the problem.. you can't "harvest" heat unless you have a significant temperature differential, and a 20F difference (~95 to ~75) is laughable.

Also, I question the idea of "waste" heat. The body heats itself enough to keep the extremities functional, and little beyond that. Making the body work harder could potentially result in hypothermia, although it could also result in a higher "resting" metabolic rate, so it really depends on whether or not the user has extra calories to spare.

There are already better/more efficient ways to convert the body's energy into electrical power; namely hand cranks. They're not passive, but they also don't require constant use, they can potentially provide *far* more power, and they don't require ideal environmental conditions to operate.

Re:Screw that

[timeOday]

Not even a wristwatch? Some run 10 years on a button battery.

Re:Screw that

[Xtravar]

Yeah, I find it kind of scary that there's a headband that will sap your brain of heat. That can't be good for your brain, can it?

Still waiting for the devices that run off sugar in the blood stream so we can all stop being fat.

Re:Screw that

[Hognoxious]

it really depends on whether or not the user has extra calories to spare.

Given tthat it's coming from a country where the diet consists of chocolate, beer, waffles (with chocolate on) and fries (with mayonnaise) I'd say they aren't exactly anorexic.

Re:Screw that

[yurtinus]

Given tthat it's coming from a country where the diet consists of chocolate, beer, waffles (with chocolate on) and fries (with mayonnaise) I'd say they aren't exactly anorexic.

Interested in losing weight without changing your diet? Boy have I got the product for you! The HeadFlex 3000 will burn calories while you go about your day, no exercise needed, and power your iPod, cell phone, or portable dialysis unit! Just strap it on, plug it in, and burn those calories!

Re:Screw that

[interploy]

Also, I question the idea of "waste" heat. Making the body work harder could potentially result in hypothermia, although it could also result in a higher "resting" metabolic rate, so it really depends on whether or not the user has extra calories to spare.

I question your relative activity level. Have you ever shoveled a driveway clear of snow? I can go out in 10F in coat/gloves/hat/scarf and have to strip down to just a sweatshirt inside of thirty minutes. I give off so much heat that my clothes are literally steaming. You're talking as if the body has a finite amount of heat to give, but that's not the case. The heat output is equivalent to the amount of energy expended. If this thing can't power a gameboy, there's no way it can sap so much heat it risks giving someone hypothermia. To do that, it'd not only have to be able to harvest more heat than the body can produce at any given level, it'd have be able to do it over an extended period of time and without the user noticing he/she's freezing.

Re:Screw that

[popeye44]

The Ice must Floe... See whut i did thar?

Re:Screw that

[Thelasko]

Not even a wristwatch? Some run 10 years on a button battery.

The article notes that this technology out performs human mounted solar cells. Seeing as there are currently solar powered wrist watches, I believe this new device is capable of powering a wristwatch, but that's about it.

Re:Screw that

[Thelasko]

So the laws of thermodynamics still apply, even in Belgium?

Yes, even in Belgium!

Re:Screw that

[Wardish]

Sorry to say, since it's a heat engine, it moves heat from warmest to coolest. In hot weather YOU are the coolest. The device would warm you up.

Re:Screw that

[demonlapin]

If you're careful - and I mean, really careful - you can go get some 2,4-dinitrophenol (I forget why, but we used this stuff pretty frequently in chemistry classes) and use it to uncouple the Krebs cycle from ATP production. You'll lose weight... quickly... extreme caution is advised. On the plus side, you can turn the heat down.

Cold?

[Hatta]

I don't understand how it can get cold. You can harvest energy from a temperature gradient, but once the headband is at ambient temperature, there's no more gradient. How does it get cold?

Re:Cold?

[oodaloop]

It feels cold because it's sucking heat out and using it. So it's constantly leaching heat out. Hence it would feel cold. Simple, really.

Re:Cold?

[Anonymous Coward]

Compared to your body temp, ambient temperature is cold. Try putting a piece of ambient steel against your skin and tell me if it's cold.

Re:Cold?

[Thanshin]

If it gets as cold as the ambient, it's as unconfortable as not wearing anything on that clothing slot. Which, beyond the polar circle, for example, can be between "quite" and "fucking".

Re:Cold?

[sakdoctor]

Those of us who descended from the mammalian evolutionary tree, keep our bodies warmer than ambient temperatures.

Re:Cold?

[Thanshin]

It feels cold because it's sucking heat out and using it. So it's constantly leaching heat out. Hence it would feel cold. Simple, really.

Heat can't be turned directly into energy, only difference in heat.

Re:Cold?

[confused one]

It's better at conducting heat away from your skin than air; and, because it's extracting energy and using a small radiator as a heat sink, it remains colder than the skin. It only feels cold. It would never actually reach ambient because your body is keeping it above ambient, with the asumption that "ambient" is well below body temperature. From the article:

"At 22C, it produces about 30W/cm2, i.e., close to the theoretical limit of power generation on people at this temperature in a compact device. There is, however, a drawback of such high power generation: at lower ambient temperatures, the heat flow rapidly exceeds the sensation of discomfort and the device turns into uncomfortably cold object. For example, at 19C, the TEG already produces 3.7 mW, but the sensation of cold becomes too annoying. "

Re:Cold?

[TummyX]

If it is constantly sucking heat energy away from you then it will feel cold. Your body doesn't feel cold from the cold but rather from change in temperature. Metal at ambient temperature feels cold because it conducts the heat away from your body more efficiently than wood for example. This device must be efficient at sucking heat away from your body in order to generate electricity.

Re:Cold?

[Issarlk]

The headband is at ambiant temperature, but your body is much warmer. Heat flow from your body to the headband and leaves a cold sensation on your skin. The material of the headband applied to the body is probably a good conductor of heat ; it's like with a piece of metal that feels cold to the touch and a piece of wood that doesn't while both are at room temperature.

Re:Cold?

[Hatta]

It's not sucking heat out, that would actually require extra energy input. It's not a pump, it's more like a water wheel.

But my question has been answered. It doesn't get below ambient temperature. We just don't feel ambient temperature as cold as it actually is, because air is a pretty good insulator.

Re:Cold?

[Mr. Slippery]

You can harvest energy from a temperature gradient, but once the headband is at ambient temperature, there's no more gradient.

Unless the ambient temperature is equal to your skin temperature, there's a gradient.

Or are you confused by the idea that something at ambient temperature can feel uncomfortably cold? A surface at 19 C (66 F) right against your forehead, actively conducting away heat, is a different sensation than air at the same temperature. It's not just the temperature, but the thermal conductivity For example, air at that temperature is fairly comfortable (little chilly for my taste), but water at the same temperature can (with long exposure) cause mild hypothermia.

Re:Cold?

[vegiVamp]

So in warm countries (or during a heat wave), when ambient is *above* body temperature, do yo wear it inside-out ?

Re:Cold?

[Thangodin]

Yeah, I was wondering the same thing. Either the ambient temperature has to be pretty cool, or the thing has to be fitted with liquid coolant--which makes it essentially a battery. Leaving this out of the explanation makes all the claims pretty underwhelming.

Re:Cold?

[confused one]

That might work with some modification but you could see how that might not be a good idea (hyperthermia bad). They did mention an increase in power production when the wearer moves from outdoors to an air conditioned indoor environment.

Re:Cold?

[carvalhao]

Although I can't name it, there was a movie in the 80's about a building that recycled human body heat for energy... until the computer went awry and started killing everyone for their body heat.

Re:Cold?

[lazn]

How about those who live in a desert where the ambient temperature is HIGHER than body temp?

Re:Cold?

[Thelasko]

It feels cold because it's sucking heat out and using it. So it's constantly leaching heat out. Hence it would feel cold. Simple, really.

From TFA:

at lower ambient temperatures, the heat flow rapidly exceeds the sensation of discomfort and the device turns into uncomfortably cold object. For example, at 19C, the TEG already produces 3.7 mW, but the sensation of cold becomes too annoying.

At 19C you would start to become uncomfortable whether you were wearing this device or not.

Re:Cold?

[Thelasko]

TFA states that the headband only becomes uncomfortable below 19 degrees Celsius, which is below common room temperatures. One could argue that a human would be uncomfortable below room temperature wheather they are wearing this device or not.

However, you are correct. Humans are not good at judging temperature. We are good at judging heat transfer, which is why metal objects seem colder at the same temperature as nonmetals.

Re:Cold?

[mcgrew]

Seventy degree air (21.11 C) is comfortable. Jump into a pool of eighty degree (26.66 C) water and it feels like it's freezing. Water that comes from your cold water tap in the summer is close to the ambient temperature, but soak a rag in it and wrap it around your neck and it will cool you off quickly (until the water in the rag raises its temperature to match yours).

Re:Cold?

[Rhacman]

As long as it isn't the same as your body temperature you would still have a thermal gradient to work with. Your body would be cooling itself by sweating and the device would be harvesting the heat energy that is flowing into your head through the headband rather than the other way around. http://en.wikipedia.org/wiki/Thermopile

Re:Cold?

[Yamata no Orochi]

If it gets as cold as the ambient, it's as uncomfortable as not wearing anything on that clothing slot. Which, beyond the polar circle, for example, can be between "quite" and "fucking".

You play too many video games.

Re:Cold?

[selven]

As you said, the headband approaches ambient temperature. In the winter, ambient temperature is -4, ie. cold.

Re:Cold?

[lena_10326]

We just don't feel ambient temperature as cold as it actually is, because air is a pretty good insulator.

Also, we are warm blooded so heat generation is constant like a treadmill. In order to prevent heat buildup and feel comfortable, the heat has to transfer from the body to the environment which requires a temperature difference, which is why 98.6F ambient temperature feels hot to us, but 72F feels comfortable because the air conducts away heat at a balanced rate of exchange. As you mentioned air is an insulator so heat conduction is slower than with solids such as metal or plastic. Exposed to open air the skin's surface temperature drops a little but does not reach ambient temperature because of body's continual heat generation. A head band with plastic or metal contacts would conduct away more heat so the skin's surface temperature will drop further, which is why solids feel colder to the touch.

Re:Cold?

[Arthur Grumbine]

Those of us who descended from the mammalian evolutionary tree, keep our bodies warmer than ambient temperatures.

What about those of us who were brought to life from the primordial marinara soup by the touch of His Noodley Appendage, you insensitive clod!

Re:Cold?

[ceoyoyo]

At a comfortable ambient temperature your body is usually a good deal warmer than the air. I'm sitting in a room with about a temperature of 22 degrees right now, and that's a little warmer than I'd like, but there's still a healthy temperature gradient between that and my 37ish degree core temperature.

Try sitting in a bath where the water is at ambient air temperature and see if it feels cool or not.

Re:Cold?

[ceoyoyo]

Your quote dropped a "micro" symbol. 30 W/cm2 is enough to power my laptop from a bit of skin about the size of my thumb nail.

Re:Cold?

[srobert]

That would include almost everyone on Slashdot.

Re:Cold?

[RsG]

Broadly speaking, I'd expect those living in deserts to find other solutions. You don't wear the same clothes in two diametrically opposite climates - why would that change simply because the cloth is high tech?

The obvious, not yet developed choice for people in a hot environment would be cloth with embedded solar collectors. If you want to hedge your bets, bring some of each, and dress for the climate as needed. Of course, all of this takes for granted the affordability of such solutions, but to be blunt I don't see either one becoming the norm in the next 10-20 years anyway.

Re:Cold?

[lewiscr]

You must live up north. In the Southern US, we try very hard to keep our bodies below ambient tempature. It avoids all that nasty dizziness, coma, and death business.

Re:Cold?

[hesaigo999ca]

Actually, as funny as you are trying to be, mod points to you for that, there is an episode (on sg1) which brought light to this issue, that there was such a device that sucked up heat, used in the middle of the desert. All the scientists had come to see it, so in essence, was supposed to play out like it should,
however for x reason something failed, and there was no counter measure except an air shield to keep the base which was hosting the experiment secluded from the rest of the globe.

The error was fixed, but not before seeing what sucking out all the heat from the atmosphere could do
in terms of damage, and at some point, if the shields had failed, it would have continued globally.

The technology used here is using body heat for its use, but as you say, what happens when we use it in an atmosphere where the air is hotter then body heat, would there be no need for the body to begin with...
as well, if this WAS the case, why not create these to harness the full extent of the heat in a desert or the like.

Re:Cold?

[JWSmythe]

    That all depends on where you usually live. Here, our "normal" comfortable days are about 78F. Our "warm" days are about 90F. Our "it's hot" days start at about 100F. Right now, it's 68 degrees outside, and you don't see anyone without a jacket, and all buildings are heated to at least 75F.

    It usually takes me a little while to acclimate to traveling to northern states. After a few days, I look perfectly at home standing in the snow, but for those few days until I get used to it, I'm freezing.

Re:Cold?

[JWSmythe]

    But that depends on your time of year, and altitude. :)

    Here's it's a downright cold 68F now. It's the two weeks a year to wear a jacket. :)

Re:Cold?

[JWSmythe]

    I don't remember that episode. Of course, as soon as I watch it, I'll remember it.

    I remember Carter was on a planet with two suns, and a dead DHD, so they were trying to figure out how to make it cooler for them to survive. "Well, we could send these reflective blankets...." did go over so well. :)

    Of course, O'Neill had the entire ancient database in his head, so he sent over instructions on how to fix it just in time. Funny, how they always manage to save the day, just in time. :)

Re:Cold?

[LanMan04]

Exactly. A metal pole outside in the winter "feels" a hell of a lot colder than the air does at the same temp.

Hooray for that little micro-layer of air that stays close to your skin to keep you toasty (and when it gets blown away by wind, you feel colder, hence "wind chill").

Re:Cold?

[Mordstrom]

Fricking MOVE its a DESERT you morons!

Re:Cold?

[hesaigo999ca]

I think it was the atlantis one, where McKay comes to earth to visit his sister or something like that , and gets involved with a whole bunch of his ex friends....in the middle of the desert to see this new toy.

Re:Cold?

[Zagnar]

I would highly recommend this episode, if only to see Bill Nye slap someone.

Re:Cold?

[JWSmythe]

Are we talking about Stargate Atlantis, Season 5 Episode 16, "Brain Storm"? I don't think I've seen this one. There were some gaps in my viewing of Atlantis, and I suspect this may have been one of them.

Re:Cold?

[lena_10326]

It also explains why you get hypothermia faster submerged in water when compared with exposure to air of equal temperature.

Re:Cold?

[treeves]

Yeah, I remember Sam Kinison too.

Re:Cold?

[hesaigo999ca]

A worth while one to download and watch

Ah, the joys of biofuels

[bradm]

I suppose now we'll all wear parkas and cram energy bars during our kernel compiles?

Anyone know the cost per KWH of corn syrup?

A personal airconditioner?

[rolfwind]

If this is true:

In fact, the researchers mention that the energy harvesting head band works so well that it can get uncomfortably cold.

Wouldn't it be extremely marketable? Especially for the military with troops in hot places and with bulky body armor and probably all types of personal electronic equipment to keep charged?

Re:A personal airconditioner?

[DallasMay]

Probably wouldn't work in Iraq. If this does work, it would pull heat from you and into the ambient environment. That means that there has to be a temperature drop between you and the air for it to work.

Re:A personal airconditioner?

[dvoecks]

That only works if the air temp is lower than 98.6. This sort of thing works by harnessing the difference in energy between the "hot" side and the "cold" side. Sure, it would work well at room-temperature, but who needs cooling at room-temp? About the only time you really need cooling when the air is significantly below normal body temperature outside is when you've got a fever, or are heavily exerting yourself. I definitely could get behind a headband that powers an mp3 player when I'm on a jog. It could have military applications, but it would be fairly limited. When it's 120 degrees in Iraq, this thing wouldn't work even if the soldier was running a marathon while dragging a broken down Humvee.

Re:A personal airconditioner?

[Adhemar82]

Time to invade Siberia!

Re:A personal airconditioner?

[Thelasko]

Wouldn't it be extremely marketable? Especially for the military with troops in hot places and with bulky body armor and probably all types of personal electronic equipment to keep charged?

This also defies the laws of thermodynamics. Allow me to explain:

1. In Iraq, the surroundings are hotter than the human body. Therefore, it is impossible to harvest energy from human waste heat because heat is flowing to the human, not away from it.

2. The temperature gradient between a humans body and it's surroundings is not large enough to generate significant amounts of electricity. If it was, internal combustion engines would be a hell of a lot more efficient than they are today.

3. If the temperature gradient between a human body and it's surroundings were large enough to generate significant amounts of electricity, you might want that energy to keep warm!

Re:A personal airconditioner?

[vegiVamp]

You'd still have a temperature gradient, just the other way round.

Re:A personal airconditioner?

[Jake Griffin]

Which means it would feel uncomfortably hot rather than uncomfortably cold. Kinda defeats the purpose of cooling off the soldiers.

Re:A personal airconditioner?

[Jake Griffin]

Sorry for the double post, but I had another thought. I honestly don't believe that this would work as well with the hotter ambient temperature because of how much better our skin is as a conductor as opposed to the air... I could be mistaken however, as I'm not totally sure how this works.

Re:A personal airconditioner?

[mcgrew]

Sure, it would work well at room-temperature, but who needs cooling at room-temp?

If you live in a dry climate, over a hundred degrees F isn't bad unless you're in the sun. In a humid climate eighty five is uncomfortably hot, as your sweat won't evaporate as well. It probably wouldn't work well in Arizona in the summer, but it would be great in a place like St Louis or (moreso) Thailand.

It would have worked well in Viet Nam, probably wouldn't work at all in Iraq.

Re:A personal airconditioner?

[dintlu]

While human core temperature is generally 98.6, our skin temperature is typically between 85-95 F, depending on environment and where on the body the temperature is measured.

Re:A personal airconditioner?

[Locke2005]

It only makes you feel colder if there is a significant temperature differential between your body and the surrounding air. In places where the surrounding air is warmer than your body temperature, it wouldn't work at all. Also, just mounting a heat sink on your head would be more effective at cooling you then this device, which has more thermal resistance since it is trying to extract energy from the heat transfer. ("Look at me! I've got aluminum fins on my head!")

not usually how it works

[v1]

As a side benefit, the power sources help cool you down

Typically if you take something that's trying to dump waste heat, and install something that recovers power from that heat, it creates an insulating effect, reducing the cooling the object was receiving. Heat can't be turned directly into energy, only difference in heat. Adding a heat reclamation system doesn't help cool something down because the power it's getting is from the temperature difference, not the heat itself. Instead it takes power from the temperature gradient, and as such reduces the temperature gradient, thus reducing cooling efficiency.

Re:not usually how it works

[maxwell demon]

Well, unless they built a perpetual motion machine of the second kind. :-)

But actually, it may be due to the fact that normally you don't really feel the real temperature, but when it's cold, the temperature of the air directly at your skin is still higher than the surrounding air (unless there is wind, which is why you feel cold faster when there's wind). If this device has better heat transport to the surrounding air (e.g. because the surface to air is larger than the surface to you skin), you may feel colder that normally.

Re:not usually how it works

[maxume]

They are also attaching a big radiator to people's foreheads.

And the actual paper doesn't really talk about a cooling effect, it simply states that the contact with the device becomes uncomfortable in ambient temperatures much below 22 Celsius.

Re:not usually how it works

[jollyreaper]

Typically if you take something that's trying to dump waste heat, and install something that recovers power from that heat, it creates an insulating effect, reducing the cooling the object was receiving. Heat can't be turned directly into energy, only difference in heat. Adding a heat reclamation system doesn't help cool something down because the power it's getting is from the temperature difference, not the heat itself. Instead it takes power from the temperature gradient, and as such reduces the temperature gradient, thus reducing cooling efficiency.

This would be the reason why fremen stilsuits would be impossible, right? Even as a kid it struck me that someone was trying to have a free lunch.

Re:not usually how it works

[JerryLove]

Yes. Power is generated when heat is moved from an area of high concentration (your head) to an area of low concentration (the air).

If the device facilitates that transfer in order to get more energy from it; then it would indeed cool you down. It requires only tha the headband be more effective at radiating heat than your skin is.

Re:not usually how it works

[vlm]

This would be the reason why fremen stilsuits would be impossible, right? Even as a kid it struck me that someone was trying to have a free lunch.

The part that kills the stillsuit is there is an inherent minimum energy requirement to separate drinkable water from uh, bodily output, and there is also an inherent minimum energy requirement to condense water out of the air. Unfortunately, to generate that energy, the human body requires MORE water than would be produced by either process... Healthy human kidneys already do a pretty near optimal job of "recycling water".

Human powered camping filters only work because only a small fraction of the water is filtered, most bypasses into the waste outlet. Getting "all the H2O" would be way too hard. Hence the lack of commercially available human powered distillation apparatus. As for condensation, human powered bicycle air conditioners are not commercially viable, nor are human powered dehumidifiers... The navy would probably find a human powered exercisebike/dehumidifier to be useful, but it just doesn't work, you'll exhale/excrete more water than you could realistically condense.

This might make a weird mythbusters episode... can someone boil away a quart of water using an exercise bike hooked up to a generator without eating/drinking/sweating/excreting more than a quart of water? Answer appears to not only be "no" for boiling, but "no" for condensing too.

Re:not usually how it works

[Shotgun]

As a side benefit, the power sources help cool you down

Typically if you take something that's trying to dump waste heat, and install something that recovers power from that heat, it creates an insulating effect, reducing the cooling the object was receiving.

Unless, the device dumping the waste heat originally had a very inefficient path for dumping the heat. You can come in, install a more efficient "heat dumping" path and then bleed off some of the difference in the form of useful energy.

Re:not usually how it works

[dintech]

Drinking your own pee has always been free.

Re:not usually how it works

[v1]

yep I forgot to mention that the statement depends on what the existing cooling situation is. If it's already wrapped in a perfect insulator, then of course the heat reclamation will improve cooling. OTOH if it's already attached to a good heat dissipator, (and sweat evaporation is very effective) then you're going to reduce cooling efficiency, and that's what this thing is doing as far as I can tell.

Re:not usually how it works

[dwiget001]

Well, there are wrist watches that wind from simple body motion.

If you combined the device this article covers with something that "winds" from simple body motion, the combination of the two might be more practical, either generating energy from motion or from temperature differential.

Of course, carrying around the batteries to keep a good store of the energy on hand might be a pain too.

Re:not usually how it works

[drinkypoo]

Actually, there's no reason stillsuits have to be impossible. I've been thinking a lot about this and the only conclusion I've come to about them is that if they're black, there must be some kind of magic insulating layer in between that and the wearer. That, or that you would never ever wear them outside without some covering. The black, presumably, is for protection from UV. But there are other possibilities; you could cover it in solar cells, and do electrolysis of water (or operate a desalination system)

Re:not usually how it works

[khallow]

OTOH if it's already attached to a good heat dissipator, (and sweat evaporation is very effective)

Dump someone naked in a cold body of water. Then you'll see very effective heat dissipation. Sweat evaporation isn't as effective as conduction of heat directly into a heat sink.

Re:not usually how it works

[tlhIngan]

OTOH if it's already attached to a good heat dissipator, (and sweat evaporation is very effective)

Sweat works when it can evaporate. In humid places, all sweat does is bead and make you wet and smelly without being effective at cooling you. So in the desert, it works great. On the coasts or places where hot and humid is the norm, not so much. It's why it can be 100F in Arizona in the shade and still feels cool, while New York is stifling and it's only in the 80s. It's also why air conditioned places feel so much better even if you don't set the temperature much lower than outside - the lack of humidity makes the place feel cooler.

It's the reason for the "humidex" readings. (Unfortunately, it also works in reverse - cold and humid places feel colder than drier places).

Yeah, I find it kind of scary that there's a headband that will sap your brain of heat. That can't be good for your brain, can it?

The brain is a huge consumer of energy, and it's very exothermic. In the winter, it might not be terribly good for your brain as cold causes blood vessels to shrink and the like, but in the heat of summer, anything that helps cool your head down will aid in alertness and improved mental capability. Heck, the simple act of cooling your forehead has been shown to relieve tiredness in the summer. So if you're nodding off at your desk, maybe apply a cold wet towel to your forehead and it'll help perk you up a bit.

All I have to say...

[ultraexactzz]

Welcome to the desert of the real...

Free Energy?

[lobiusmoop]

FTFA:
"Imagine portable electronics that run on a free, reliable energy source."

Um, I'm already practically there. I can get a KWh out of the wall for 5p (10c), charge up an iPhone from dead to full for a quarter (5KWh battery capacity there) and can get as many cheap chargers as I like. On my list of concerns right now, body-heat chargers are pretty far down.

Re:Free Energy?

[Shikaku]

Brown energy is the new green! The brown energy is the product of human heat generation. This brown energy can be used to fertilize crops.

Re:Free Energy?

[Anonymous Coward]

http://en.wikipedia.org/wiki/Battery_(electricity)#Rechargeable_battery_chemistries

I'd love to know where you get 5 kWh from an iPhone battery. Li-Ion batteries have an energy density of 128 Wh/kg, so your iPhone battery must weigh 39 kg.

Granted, a 5 kWh Li-Ion battery will cost a fortune, so for something of that capacity, you're more likely to use a lead-acid battery of car/alarm/emergency light fame. That battery would weigh 129 kg. My brother-in-law has an iPhone; I'll ask him if it came with a dolly for the battery.

Now, it would make more sense if that was a 5 Wh battery; then we're talking about 39 grams, which is probably a bit easier to carry around. And your charging cost is down to 0.005p, but will likely be a good deal higher due to energy loss.

Re:Free Energy?

[jeffb (2.718)]

Um, I'm already practically there. I can get a KWh out of the wall for 5p (10c), charge up an iPhone from dead to full for a quarter (5KWh battery capacity there) and can get as many cheap chargers as I like.

Um, I think you're off by at least three orders of magnitude there.

On my list of concerns right now, body-heat chargers are pretty far down.

Well, as long as you spend your whole life no more than a few hours away from a power outlet, that makes sense.

I'm still not buying the body-heat solution, though. Let's get something that runs off blood sugar instead.

Re:Free Energy?

[Hoi Polloi]

Or it can be used to power the Matrix for our computer overlords.

Re:Free Energy?

[oodaloop]

And once your phone never needs to be re-charged again, you'll wonder how you ever lived with something as archaic as plugging it in when it was low. Also, it may be cheap to you, but that doesn't mean it's cheap to, say, the environment. Having the population of the UK charge their devices off of coal-fired power plants instead of human generated heat isn't exactly optimal.

Re:Free Energy?

[lobiusmoop]

LOL, sorry, my bad. Need more coffee...

Re:Free Energy?

[vlm]

Also, it may be cheap to you, but that doesn't mean it's cheap to, say, the environment. Having the population of the UK charge their devices off of coal-fired power plants instead of human generated heat isn't exactly optimal.

Its a "well known fact" that it takes about 10 kcal of petroleum products to make about 1 kcal of food, on average. Natgas turned into fertilizer, diesel powered everything, processing plants, shipping, etc. And the efficiency of the conversion device is probably not too good. And the efficiency of the human body at turning food into heat is not too good.

So, ignoring capital costs, unless the UK power system is substantially below 1% efficient, you'll end up environmentally ahead using wall outlet power. On the other hand, environmentalism has replaced the old catholic church system of feeling guilty and being inconvenienced, and this tech might work for that, in which case it could be extremely "environmentally optimal" in a sociological sense.

Re:Free Energy?

[Skater]

Flaw in your argument: people already exist and eat that food anyway. This idea is to take heat that already exists and is being wasted (sometimes) and make it do useful work for us.

Re:Free Energy?

[mdarksbane]

Of course, if this device is pulling heat faster than the surrounding air, you will need to burn more calories than before to continue powering it.

If you're in a situation where your body is already dumping heat as fast as it can (ie, you're sweating) it's recapturing waste energy. If you're in a cooler environment, though, the heat will need to be replenished by burning calories to maintain temperature. Users would either lose weight or eat more.

Of course, all of this is a fair amount of bullshit since the effect of any such device is so small as to be completely pointless in environmental terms.

Re:Free Energy?

[mcgrew]

It's only "free" in the sense that an empty potato chip bag is free. You paid for the bag when you bought the chips, and you also paid for the waste heat when you bought the chips.

Re:Free Energy?

[Xtravar]

It's called Milorganite. http://en.wikipedia.org/wiki/Milorganite

Wait, What happens if your head gets too hot?

[Anonymous Coward]

If your head gets too hot with the hat on, simply put another heat absorber around your hat. If your head gets too cold again, put on another hat.

Re:Bullshit

[jdunn14]

I was going to just mod you down, but the summary at least never said anything about lowering any part of the device below ambient. It said that the headband will "feel cold". Touch a piece of wood at room temperature. It will sometimes "feel" warm. Do the same thing with a piece of steel. It will "feel" cold. This is true even if both are at the exact same temperature. Heat conduction

The kids section of my local science museum even has hand-shaped pieces of different materials to demonstrate the effect.

Canada

[Galestar]

I live in Canada... I need all of my body heat as it is.

Re:Canada

[TheGreatOrangePeel]

I live in Canada... My wife needs all of my body heat as it is.

There. Fixed that for you.

Re:Canada

[josh61980]

Amen.

They've come a long way!

[Lord Lode]

I was a student at this university, some 5 years ago all students who visited IMEC had to do an experiment for them, namely wear a watch with this technology and then it'd generate a few microwatts out of the difference between the outside and body temperature. They even gave a funny speech related to The Matrix before the experiment. It seems they've improved a lot in the meantime, though it's a shame the article doesn't mention how much power it currently generates.

Re:They've come a long way!

[confused one]

Ummm, yeah it did. The pulseox meter required 62 uW. A watch sized device could theoretically generate between 100 and 600 uW per the article. The headband was generating 30uW/cm^2 for 3.7mW at 19C during their testing. The shirt required 0.5mW, was generating 0.8 to 5.5mW. All depending on the users activity level and the ambient conditions.

Overrated

[ooctav]

Hamsters are overrated.

Re:Overrated

[Locke2005]

Is that why you always use gerbils instead?

Wristband blood oxygen sensor?

[wcrowe]

While that's pretty interesting, I'd like to see a non-invasive wristband blood glucose sensor. Now that would be something.

Re:Wristband blood oxygen sensor?

[quercus.aeternam]

If you need continuous monitoring, you probably need more accuracy than non-invasive means will get you.

As of 2003 (when I spent a summer internship at Sensys Medical), the best non-invasive method (near-infrared spectroscopy) would get you within 20% of the actual value - and that's with an initial blood sample for calibration. IIRC, most consumer devices are accurate to 10-15%, with cheaper clinical devices being accurate to 5%.

Knowing the hardware necessary for even that degree of accuracy as well as the difficulties we had getting a clean signal while trying to shrink stuff down to shoebox size, there's no way that this would work - not with IR, anyway.

The accuracy should have improved since then, and these numbers are purely from memory. That said, you are right. That would be something - but given accuracy and demand, don't plan on it in your lifetime.

Re:Wristband blood oxygen sensor?

[wcrowe]

Hey, thanks for the post. I've never talked with anyone who has worked in the field before, so it was interesting.

Re:Wristband blood oxygen sensor?

[eheldreth]

While I agree with the sentiment of your statement, I'm not sure it's completely accurate. Such a device could be useful in driving the basal rate of insulin delivery in a pump. It may also allow for the detection of a spike in blood sugar and the automated administration of a bolus to deal with it. If you are doing continuous monitoring you may also be able to boost the accuracy of the device by averaging blood sugar levels instead of relying on any one reading. Don't underestimate how much non-invasive testing would improve the quality of life for diabetics.

Not a heat pump!

[burisch_research]

Any heat harvesting system relies on a temperature differential - in this case, the temperature difference between your body and the air. If the device were a perfect conductor of heat, a) it would generate no power at all (because there is no temperature differential) and b) this would be pretty much identical to not wearing the device at all.

In reality, all such devices must be imperfect heat conductors (i.e. they insulate heat), and as such your skin temperature will always be higher than it would be if you were not wearing one of these. (obviously this ignores the comparison between how efficiently your skin dissipates heat, vs how quickly the 'cold' end of the thermopile does.)

It has begun

[quatin]

Morpheus: What is the Matrix? Control. The Matrix is a computer-generated dream world built to keep us under control in order to change a human being into this. [holds up a Duracell battery]

But in all seriousness. There were previous articles about physical implants into the body that run on body heat. The idea isn't so new, this is just less invasive.

Re:It has begun

[mcgrew]

There were previous articles about physical implants into the body that run on body heat. The idea isn't so new, this is just less invasive

I would think that would only be used to power devices that needed to be implanted; pacemakers, etc. It would actually be less invasive, because you wouldn't require periodic surgery to replace the power supply, and you wouldn't have to have wires hanging out of your body.

The device implanted in my left eye* is powered by the eye's focusing muscles. It seems that a pacemaker that was powered by your heartbeat, like my implant is powered by focusing muscles, would be more practical.

* CrystaLens IOL

Blue Smarties. . .

[Fantastic Lad]

Though perhaps they won't need massive amounts of force to subdue humanity; from what I've seen, most people would choose the blue pill.

I've long believed that the physical reality we live in, being entirely a product of energy and thus little more than an illusion, the idea of matter and as such is inherently linked to consciousness. . , that all things in our reality can be observed as and understood to be metaphors for systems and conflicts we are experiencing in our conscious awareness.

-You have to plug humans into the Matrix at the start of their lives when kids are most inquisitive. Red Smarties are the most popular color, and the battle over Blue Smarties rages on. . !

In 2006 it was announced that Nestlé were removing all artificial colourings from Smarties in the UK, owing to consumer concerns over the effect of chemical dyes on children's health. Nestlé decided to replace all synthetic dyes with natural ones, but as they were unable to source a natural blue dye, the blue Smarties were removed from circulation, and white Smarties were introduced in their place. White Smarties were later removed from the range, and blue Smarties were re-introduced in the UK in February 2008, using a natural blue dye derived from the cyanobacteria spirulina.

Dieticians [...] said that the blue coloring was the one which was most likely to cause intolerance in kids. "The thing about blue is there are no natural equivalents. All the others can be obtained from natural sources," said Linda Hodge, a dietitian. "I believe the Brilliant Blue causes the worst symptoms of chemical intolerances."

She added that when consumers are being tested for intolerances, the first color tried out is yellow. "When we are trying to determine if a person is sensitive to food coloring, we test them first on yellow. If there is no reaction we then use red, then blue. We don't start off with blue because it is a the strongest color and gives the worst reactions," she observed.

Humans naturally try to reject the Matrix. "Entire crops were lost."

Neat, huh?

-FL

Re:Blue Smarties. . .

[camperdave]

Back in the 1960s, or perhaps the 1970s, before the "When you eat your Smarties, do you eat the red ones last?" campaign, Smarties were marketed with a song that included the line: "You'll see red, two shades of brown, but you'll never, ever, ever see blue". To this day, I feel betrayed every time I eat a blue Smartie.

Re:Blue Smarties. . .

[Anonymous Coward]

Sounds like a vague prelude to some crazy scientology rant. Don't go down that rabbit hole, pal.

Re:Blue Smarties. . .

[brianerst]

Interestingly, Brilliant Blue can help treat spinal cord damage. That makes sense, though - in order for the Matrix to work, you'd need a good way to fix the trauma caused by adding the headjack. Take the Blue Pill...

Re:Blue Smarties. . .

[Fantastic Lad]

Sounds like a vague prelude to some crazy scientology rant. Don't go down that rabbit hole, pal.

Dude. . , "Follow the White Rabbit!"

Scientology is messed up and evil, but so what? The universe is beautiful and terrifying and it is not for the meek. Blue Smarties are for the meek.

-FL

Re:Blue Smarties. . .

[OglinTatas]

Humans naturally try to reject the Matrix. "Entire crops were lost."

I don't reject the Matrix so much as I reject The Matrix 2 and 3.

Re:Blue Smarties. . .

[hal9035]

"..........so rational folks can develop a proper avoidance strategy. " not avoidance, but exploitation, strategy ready, GO!

Re:Blue Smarties. . .

[Fantastic Lad]

Scientology, like all religion, exists to get the idiots to willingly identify who they are, so rational folks can develop a proper avoidance strategy.

Well put.

-FL

Re:Blue Smarties. . .

[gid]

Nonsense--Matrix 2 and 3 were never made. Too bad, as The Matrix was such a good movie.

Re:Blue Smarties. . .

[plasticsquirrel]

You are reinventing Buddhism, actually, which is mostly what the Matrix copies as well. The Buddha taught 2500 years ago that you don't have a body, the entire world is an illusion, and that mind is the only reality that human beings have ever experienced, or could even hypothetically ever experience. That all reality is observable through eight consciousnesses, some of which are associated with sense organs, and others which are more fundamental. There is a complete model of the mind all of its faculties, including the conception of thoughts. At the most fundamental level is a consciousness that is the complete non-duality of mind and matter.

If you want the details, the consciousness-only school developed them in India and then in China. However, most academics cannot understand the texts because they are heavily dependent on logic, technical terminology, and a model of the mind based on empirical observation of thoughts and phenomena in meditation. However, if anyone is interested, the basic text is quite short and is called the Sandhirnirmocana Sutra. However, the most technical text in English, is the book written by the Chinese master Xuanzang Treatise on the Perfection of Consciousness-only. Even for Lisp or Haskell-breathing intellectual programmers, these texts should prove quite challenging. And I fear westerners who pride themselves on their understanding of western philosophy would have no chance at all. There are extremely few people who read and understand this material, sadly.

Re:heat can be used to power stuff

[blai]

The news here is how small the heat gradient we're working with.

Internal use?

[srothroc]

I'd really be interested in seeing if this could safely be used inside the body somehow. You could use it to power pacemakers. More relevant to my own interests, it could possibly power an internal assembly for a cochlear implant processor. It would be nice to get rid of all of the external bits so I could run, jump, swim, and wear hats normally.

Re:Internal use?

[confused one]

You have to have a heat sink as well as a source. Some component would have to remain outside to act as a radiator.

Re:Internal use?

[TubeSteak]

I'd really be interested in seeing if this could safely be used inside the body somehow.

Probably not very useful internally because you need a temperature differential.
Unless you're willing to poke a permanent hole in the skin for a radiator,
existing (rechargeable) battery technology is much better for internal use.

Re:underpants

[Shotgun]

Yeah, and the underpants will be good for playing contact sports also, because they will be made of metal. Give new meaning to the "Under Armour" brand of sportswear.

Re:uh oh

[Richard Dick Head]

The matrix is coming......

No. We're already in the Matrix. What we're talking about here is a Matrix inside a Matrix. Its kind of a neat concept, and kind of meshes with the whole idea of the age old "tree of life" concept, where this ephemeral god concept is the head node, which branches to child archangel nodes, which then branch to angels, which all fan-in to a single child "heaven" object, or love-area. Some of the angels "fell", meaning their head nodes became the heaven object, and instead of this interesting god-angels-heaven circle, the branching continued, ultimately leading to the creation of this universe.

I would point out that we as consciousness-seeking race are busy playing god, and creating universes, such as can be found in games, puzzles, stories, religion, books, mathematics, science. And those developed in precisely that order. Games is to god, as puzzles are angels, as stories are to people, as religion is to angels, as mathematics and science are to god. Its all one big recursive refinement loop.

How many watts is this?

[selven]

How many watts would this kind of thing provide? Would it be enough to power a basic computer? I suppose it depends a lot on ambient temperature, wind speed (which constantly renews the temperature differential) and body heat (higher when you're physically active).

Re:How many watts is this?

[slicerwizard]

OMG. How many watts will this supply? NONE.

That stupid gold headband produces less than 4 milliwats (0.004 watts).

A small solar cell by a window will blow it away. You will not be using it to power a computer - or even an MP3 player.

Re:How many watts is this?

[selven]

Ok, wow. Is that even enough for a watch?

We could make an entire suit out of this stuff and put solar panels on top of it. Could that give half a watt at least?

Re:How many watts is this?

[slicerwizard]

Watches draw very little power, so yes you could.

Half a watt? Sure - with solar panels alone. But exactly watt would be the point?

Re:uh oh

[sorak]

The matrix is coming......

Only if you think that the care and maintenance of a human is the most efficient way to power a wristwatch.

Re:I'd prefer a cock ring.$

[Xaedalus]

God bless you, Adolf. I needed that this morning :-)

Fashion?

[govt-serpent]

Headbands? Wristbands? Welcome to the 80s...that's gonna look so cool

Best PR Slogan for Sustainable Energy Campaign

[hashax]

Hmm call me a perv but judging from an activity when people get quite hot and sweaty and release body heat...

Power the Future. From your Bedroom.

Or:

The Future Generation is in Your Hands.
  - double pun whammy.

yes yes I know, but...hehe.

Oh! Dear me!

[TheGreatOrangePeel]

"Researchers in Belgium..."

Oh my! Such profanity!

I wonder

[OpenSourced]

If they can make an appliance that gets electricity from body heat and can be "uncomfortably cold", could they turn it into an air-conditioning device that run on its own, or even generate electricity while cooling? _That_ would be an invention.

Re:I wonder

[jameskojiro]

The Laws of thermodynamics don't work that way....

Wrong "true potential"...

[denzacar]

Turn on your TV during the "infomercials".
Half of those are for some kind of device or chemical that will let you burn "all that fat" in days with minimal effort.

These devices siphon the energy from your body in order to work.
And you get that energy from food.
See where I'm going with this?

How many heat-harvesting headband do you need to burn out a single twinkie?
Who cares! I've seen them sell patches made out of "green tea extract" that should "burn calories" when you wear them.
10 to 1 that you get to burn more calories from a simple cup of green tea.
And that is just the things that actually have a measurable effect.

Golden heat-harvesting headbands that burn fat? Those things would sell like hotcakes.

Re:heat can be used to power stuff

[Gilmoure]

I'm thinking I may finally be able to put those poop machine cats to work. If there's a way to make a power generator band for animals that can broadcast power to a house receiver...

Re:uh oh

[Anonymous Coward]

Good day, young lads! :)
 
This is ac's mother, Shirleena. What this man says is true & I love him for it. Coppertop.

matrix

[gellern]

Oh no, its matrix!

Just one problem...

[Locke2005]

How well does it work when the ambient temperature is above 98.6 F? I think the answer you're looking for is "not at all!"

Re:uh oh

[Locke2005]

Man, what have you been smoking? I gotta get me some of that stuff!

But Is it powerful enough... ?

[TerrenceCoggins]

Is it powerful enough to charge an ipod? I'll wear the cold hat for an hour to get my phone another hour of life - but any more than that and you're pushing it...

Feel cooler?

[PPH]

This doesn't make any sense. For a Carnot cycle heat engine or a thermopile to work, you have to have a temperature difference between the source and the sink. Assume that the radiating or convecting sink that this device uses is no more or less efficient than that of your clothing or forehead: The resulting delta T that does the useful work would mean that the source (i.e. your skin) must be hotter than the sink. Or hotter than it would have been had you not strapped this gadget on.

This would be great for use in cold climates. In fact, if the system could be throttled and that in turn changes the heat flow through the device, you could 'climate control' yourself in much the same way as adding or removing layers of clothing. But in hot climates, the 'source' (you) would have to be hotter than it would otherwise. Not good. And for ambient temperatures above around 80F, the principle method of heat elimination is perspiration and evaporation. I don't see how this system could help keep you cool, let alone work at all, in these temperatures.

Re:Bullshit

[HEbGb]

Wrong.

Read the summary:

"In fact, the researchers mention that the energy harvesting head band works so well that it can get uncomfortably cold."

It "gets" cold; it doesn't just start that way. If it's cold to start with, your body will warm it very quickly, even with a good heatsink. Then it's no longer cold. Just like the science-museum materials you mention.

They clearly imply that they're effectively drawing heat away, which is just wrong.

Then they go on to suggest a hat/insulation to reduce the effect? Well, that brings the whole apparatus higher in temperature, reducing the differential, and reducing the effect.

This thing is worthless.

Waste heat?

[l00sr]

Isn't this a bit like creating a device that captures the 'waste cold' of a refrigerator?

What about power plants?

[okmijnuhb]

Don't power plants dump excess heated water back into rivers? Could this be used to capture some of this large scale energy waste as well?

Fondly Fahrenheit

[Anomalyst]

All reet, all reet
So jeet your seat
Be fleet be fleet
Cool and discreet
- Alfred Bester

Re:I'd prefer a cock ring.$

[gid]

Caution, Avast! detects this link as a trojan.

Re:I'd prefer a cock ring.$

[gregarican]

Not unless you consider the GNAA Last Measure a trojan :-/

It's been awhile since I've been Goatse-ed, and I should've known better to check the link first. Very nice way to round out my afternoon with my cube-mates...sigh...

Not much power generated

[physburn]

If you read the paper, they get between 7 and 30 microwatts per square centimeter of body, thats a tiny ammount, thats not going to power your laptop, and it isn't going to get much better. The human body is only slightly hotter than the room its in, say 38 Celius versus 20. That leads to a tiny Carnot efficenty which is the best physics allows, then you need to factor in that thermocouples and thermoelectric generators are only a few percent efficient, so you end up with a tiny ammount of power generated, it might run a very efficient wrist watch but nothing more.

---

Thermodynamics Feed @ Feed Distiller

Re:Not much power generated

[Foske]

You are true, but:

The main reason why not more power is extracted is the loss of comfort for the human being. You can compare it with cooling down quickly when standing in a cold breeze after doing some exercise.

Your laptop is not very efficient with power. IMEC (and especially the Dutch department in the Holst Centre) is not only working on the energy harvesters, but also on more efficient electronics, both digital and analog. Ok, powering your laptop is not possible in the near future, but more than a wristwatch should definitely be possible. For example heart problem or epileptic detection devices. The power budget we aim at is an average power consumption in the magnitude of hundreds of microwats, which is more than enough for some applications.

Disclaimer: I work at the Holst Centre, but anything I write here is my own opinion and is not necessarily the official opinion of my employer.

You know what I've come to realise...

[noisyinstrument]

ignorance is bliss.

Re:uh oh

[Thing 1]

To expand on your idea: well before the movie was created, I was convinced that we were living in a simulation. And, one of our goals is to create a perfect simulation of our current reality, so that we can have game machines in which you wouldn't be able to tell whether it was real or artificial. But then, if we could create such a program for our (future) computers, then perhaps everyone will be running one, and that taxes the existing simulation.

And then, let's assume that the existing simulation is just a prototype, running on some grad student's adviser's computer. Once we've achieved sufficient technology to have "a Matrix on every desktop", and the simulation starts to approach 100% of the CPU cycles, the adviser will decide that enough is enough, and pull the plug on his grad student's program (so that the adviser can do useful work with his hardware).

We will then cease to exist.

What I really like about this thought experiment (yeah, like your other responder one could ask, "what the hell were you smoking when you came up with this"), is that we strive for something that will ultimately destroy us. Of course, this theme is rife throughout our art and culture -- it's where Luddites come from, and it's also described in various religions via "hubris", i.e., "his pride was his downfall".

Re:uh oh

[Richard Dick Head]

Well, thats the neat part.

Assuming you are descending down the tree, searching for yourself, or your nearest match (which is what most people do). If the node that is "you" is removed from the dataset, then:

a. Your match and your nearest match are now identical, and that result is meaningless. b. You may realize that you can be in the tree, and outside it as well, hence you can select your position in the tree at will. This type of exterior view is called a soul, and it is the part of you that can be anyone or anything at any time. That is why spiritual teachers profess that love is the answer, because otherwise you wouldn't want to put your heart and soul into the world around you long enough to learn more about how people really are, how things work, and how to meaningfully exist outside of the tree.

Re:heat can be used to power stuff

[Golddess]

Silly human, cats are also heat-powered much like these devices. Why do you think they spend so much time on laps, over register vents, and in sun beams?

Sunlight is not consistent, so you'd need a backup power source to power your cat. But whether it's
1) You power cat, cat powers house, house converts power to heat to warm you.
Or
2) House register vent powers cat, cat powers house, house converts power to heat to warm cat.
All you'd be doing is converting the energy in a circle.

Reminds me of the "battery powered recharger that's only good for recharging its own battery" from an episode of the old Garfield and Friends cartoon.