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Could Earth's Infrared Emissions Be a New Renewable Energy Source?

samzenpus posted about 6 months ago | from the power-up dept.

Earth 78

Zothecula (1870348) writes "Could it one day be possible to generate electricity from the loss of heat from Earth to outer space? A group of Harvard engineers believe so and have theorized something of a reverse photovoltaic cell to do just this. The key is using the flow of energy away from our planet to generate voltage, rather than using incoming energy as in existing solar technologies."

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Power density? (4, Insightful)

gregor-e (136142) | about 6 months ago | (#46541203)

Just how many watts per square meter are capturable this way? Enough to power a small LED?

Re:Power density? (1)

invictusvoyd (3546069) | about 6 months ago | (#46541327)

Is this even remotely comparable to raw sunlight?

Re:Power density? (4, Insightful)

busstop (36269) | about 6 months ago | (#46541389)

The diurnal mean of the energy emitted is equal to the energy received (otherwise the oceans would quickly boil away).

The difference is that the energy emitted has a much higher entropy than the energy received: solar energy comes from a source with a temperature around 6000 K, i.e. low entropy, Earth emits the same amount of energy at a temperature of around 300 K, i.e. high entropy.

Hence, it is much harder to get any useful work from the emitted than from the received energy.

Re:Power density? (2, Informative)

BlackPignouf (1017012) | about 6 months ago | (#46541913)

Score 5: Interesting/Insightful. WTF?

*) Diurnal. Does it mean what you think it means?
*) Energy received and energy emitted by the Earth aren't equal. You might have heard of global warming.
*) The energy emitted by the Earth isn't all infrared radiation.( http://en.wikipedia.org/wiki/F... [wikipedia.org] and http://www.eoearth.org/view/ar... [eoearth.org] )
*) Temperature doesn't have color, pressure doesn't have speed and energy doesn't have entropy. You can only define entropy for a thermodynamic system (i.e. Earth, or Earth + atmosphere).
*) Entropy more or less describes the disorder of a system. All oher things being equal, the entropy goes up with the temperature (0 at 0K, higher at 6000K than at 300K)
*) You're probably talking about exergy : http://en.wikipedia.org/wiki/E... [wikipedia.org]

Thermodynamics is hard. You have to define everything and understand the underlying mathematical concepts.

Re:Power density? (0)

Anonymous Coward | about 6 months ago | (#46542019)

Diurnal - Daily
The daily mean of energy emmited is equal to the energy received.

It not exactly equal, but it very close. Yes global warming is real, but the absolute difference in received and emmited energy it makes is minute. It's affect however is huge.

Temperature can be described by colour, when in a certain range. You probably just didn't think of it: http://en.wikipedia.org/wiki/Planckian_locus, when you were giving your example.

Im not sure of the phisical validity, but busstop was probably using Entropy in an information theory sense. A hot body emmits electromagnetic radiation that is less spread out in wavelenght than cooler bodies. Therefore you could say there is less uncertainty in the wavelenght of a single photon emmited at higher than there is at cooler temperatures.

A stupid idea. (2)

Geoffrey.landis (926948) | about 6 months ago | (#46542543)

Correct: it's a mostly useless idea.

The problem really is in the laws of thermodynamics.

The total energy radiated is indeed equal to the sunlight energy (although the power density is less by a factor of 4: the Earth absorbs sunlight on an area pi r^2, but radiates heat over an area 4 pi r^2)-- but usable energy is produced not by a heat source, but by the transfer of energy from a heat source to a heat sink-- the Carnot efficiency. The difficulty is that in intercepting the outgoing radiation, you necessarily put a thermal resistor into the circuit. Basically, they end up converting at efficiency characterized by the difference in temperatures of daytime and nighttime. The efficiency is terrible.

The efficency is indeed terrible. (0)

Anonymous Coward | about 6 months ago | (#46546695)

I never get why people are so set on Solar-> Electricity.

Solar -> Heat is a lot more efficient and takes a lot less technology. My father reduced his heating oil bill by 80% by putting thermal collectors on the roof and insulating the old building better. A friend who build a new house with a heat pump that basically in winter pumps heat from the ground into the house, and in summer heat from the house back into the ground.

At least in countries that have hot/cold "seasons" that seems much more efficient way to use that heat difference than trying to generate electricity from the heat difference.

Re:The efficency is indeed terrible. (1)

Geoffrey.landis (926948) | about 6 months ago | (#46547183)

I never get why people are so set on Solar-> Electricity.

Solar -> Heat is a lot more efficient and takes a lot less technology.

Absolutely. Solar heating (and hot water) is low tech, and easy to do-- it's been cost effective for quite a while.

Re:Power density? (4, Informative)

blueg3 (192743) | about 6 months ago | (#46542209)

Energy received and energy emitted by the Earth aren't equal. You might have heard of global warming.

True, they're not equal. To a reasonable approximation, they are equal: the heat picked up via global warming is tiny compared to the amount of heat added by the Sun each day (and subsequently lost to space by radiation).

The energy emitted by the Earth isn't all infrared radiation.( http://en.wikipedia.org/wiki/F [wikipedia.org] ... [wikipedia.org] and http://www.eoearth.org/view/ar [eoearth.org] ... [eoearth.org] )

True, though it's mostly infrared and albedo.

Temperature doesn't have color

No, but a distribution of radiation does. When, in physics, someone says that radiation is "X Kelvin", it's shorthand for "a distribution of radiation very close to the ideal black-body radiation at X Kelvin". The great bulk of the Sun's and Earth's radiation is black-body radiation.

You can only define entropy for a thermodynamic system (i.e. Earth, or Earth + atmosphere).

Radiation certainly does have entropy. See, for example, Planck's "the Theory of Heat Radiation" or some more modern text.

All oher things being equal, the entropy goes up with the temperature (0 at 0K, higher at 6000K than at 300K)

This is just a misunderstanding of the meaning of 6000K vs. 300K light. Though it's incorrect to just assume zero entropy at 0K.

Entropy more or less describes the disorder of a system.

It's enormously more complicated than that. That's a Brian-Greene-level description.

You're probably talking about exergy

... Are you an engineer?

Re:Power density? (1)

mdsolar (1045926) | about 6 months ago | (#46543659)

Sunlight is captured over pi*r^2 (the crossection of the Earth) but it is re-emitted over 4*pi*r^2, the surface area of the Earth, so there is a factor of four down. There is also a question of how well you can make use of the emission. The Carnot limit gives about 85% for concentrated solar power (T(Sun)-T(receiver))/T(Sun) http://en.wikipedia.org/wiki/T... [wikipedia.org] The effective temperature of the Earth at the top of the atmosphere is about 250 K while the effective temperature of a space based passively cooled infrared telescope is about 30 K http://en.wikipedia.org/wiki/S... [wikipedia.org] so the Carnot efficiency comes out about the same unless you consider just how hard it would be to get that kind of cooling. In TFA, they are on the ground and can't get too far below the ambient temperature so they at just a couple of Watts per meter.

Re:Power density? (1)

Framboise (521772) | about 6 months ago | (#46541563)

The total heat produced by radioactivity in Earth is 44.2 TW (Wikipedia).
The total solar power received by Earth by the upper atmosphere is 174 PW (Wikipedia).
This means 3937 more solar energy is received by Earth than produced by radioactivity in its interior.
Furthermore geothermal energy is high entropy energy in regard of solar energy since the temperature difference between
ground (~287K) and nearby space (>10K) (DT=277K) is much less than the temperature difference between
sunlight (5778K) and ground (DT=5491K).

In short the whole idea of converting Earth heat into electricity is completely inefficient in regard of solar energy.
The only way to use efficiently geothermal energy is to find hot spots where it is concentrated by thousands with respect to average.

Re:Power density? (1)

abhi_beckert (785219) | about 6 months ago | (#46541777)

The total heat produced by radioactivity in Earth is 44.2 TW (Wikipedia).

Which means if we can capture 5% of it, that would be enough energy to power the entire world's energy needs.

Re:Power density? (0)

Anonymous Coward | about 6 months ago | (#46541997)

The total heat produced by radioactivity in Earth is 44.2 TW (Wikipedia).

Which means if we can capture 5% of it, that would be enough energy to power the entire world's energy needs.

It would be interesting to see if such an energy source could be harnessed and yet somehow break through the corruption to deploy it to the masses without the greedy elitists locking the entire damn thing up in litigation for the next 50 years while humanity consumes itself with traditional sources of dying energy.

Think about it. If the numbers here are correct and we can achieve 5 or even 10% efficiency, such a power generator design could essentially put every power company on the planet out of business.

With a global shift of power like that, it would be 50 years before the damn patent is released, let alone coming to terms with licensing.

Sadly, building this device and capturing 5% will be easy compared to deploying it.

Re:Power density? (0)

Anonymous Coward | about 6 months ago | (#46542653)

There is no elite conspiracy stopping you from deploying it now or even years ago. Plenty of people have their own geothermal setup if the geology of your local region supports it. Although with current energy costs, it is usually cheaper to still buy electricity and just use geothermal setup as a source of warm water and heating. But if you want to try to extract electrical energy from it, especially in the winter when there is a larger temperature difference in many northern places, there is nothing stopping you from using a bunch of off the shelf generating solutions, even ones that work at low temperature difference (not cheap per watt though, and limited in efficiency by thermodynamics).

Re:Power density? (1)

Immerman (2627577) | about 6 months ago | (#46543585)

Check your numbers - 2008 global energy usage, 142,300TWh(wikipedia) /365/24 = 16.2TW average instantaneous energy consumption.
We'd need to capture 37% to satisfy 2008s energy requirements, and today's are even higher.

Then we need to worry about efficiency - assuming we could manage to get up to 10% efficiency, we'd need to blanket 370% of the planet with thermal energy collectors to satisfy current energy demands from georadiothermic sources.

Re:Power density? (1)

TapeCutter (624760) | about 6 months ago | (#46542943)

I don't think they are talking about geothermal, they are talking about infrared that is radiated back into space at night from ground/water heated by the sun during the day.

Re:Power density? (1)

Anonymous Coward | about 6 months ago | (#46541615)

If nothing else, it's surely enough to power a small TED.

Re:Power density? (1)

VortexCortex (1117377) | about 6 months ago | (#46542093)

Hmm, well, I have a hand held sterling engine that runs a dynamo and lights up several LEDs. It runs off the thermal difference between my hand an the room temperature air.

Re:Power density? (1)

bill_mcgonigle (4333) | about 6 months ago | (#46543227)

Just how many watts per square meter are capturable this way?

It seems that if you're after the earth's heat energy, you drill a deep enough hole and get it.

No space lift required.

Dyson Sphere? (1)

Nethead (1563) | about 6 months ago | (#46541211)

A mini Dyson Sphere around the earth?

Re:Dyson Sphere? (2)

Ingcuervo (1349561) | about 6 months ago | (#46541249)

wouldnt this... avoid the sun energy to get to the earth????

Re:Dyson Sphere? (2)

Nethead (1563) | about 6 months ago | (#46541255)

Yes, we become a world of programmers and gamers. The whole is is our mothers' basement.

Neckbeards (0)

Anonymous Coward | about 6 months ago | (#46541537)

Pesky fedoraed neckbeard earthlings living in their Moon's basement.

Re:Dyson Sphere? (4, Funny)

michelcolman (1208008) | about 6 months ago | (#46541451)

We might use some system that lets most of the sun's rays pass through but that blocks the infrared from getting back out. You know, like a greenhouse. Maybe we could produce some kind of gas that has these properties?

Re:Dyson Sphere? (0)

Anonymous Coward | about 6 months ago | (#46541495)

You sure thats how greenhouses work?

Re:Dyson Sphere? (0)

Anonymous Coward | about 6 months ago | (#46541527)

You sure thats how greenhouses work?

woooosh

Re:Dyson Sphere? (0)

Anonymous Coward | about 6 months ago | (#46541551)

What was the joke? A greenhouse does not "use some system that lets most of the sun's rays pass through but that blocks the infrared from getting back out".

Re:Dyson Sphere? (0)

Anonymous Coward | about 6 months ago | (#46541637)

Glass (of a greenhouse) does pass solar radiation but reflects thermal radiation. Of course the glass also traps the warmed air inside a greenhouse. The greenhouse effect (of the atmosphere) just considers the radiation part. And we already produce gases that have those "greenhouse properties".

Re:Dyson Sphere? (0)

Anonymous Coward | about 6 months ago | (#46543439)

So the glass decides which to be transparent to based on the radiation source?

Re:Dyson Sphere? (2)

Immerman (2627577) | about 6 months ago | (#46543911)

>Glass (of a greenhouse) does pass solar radiation but reflects thermal radiation

Actually, mostly not. notably IR-reflective glass is a very recent invention that is still generally considerably more expensive that normal glass, much less plastic, etc. Most greenhouses primarily rely on retaining a mass of heated air separate from the outside environment, a job done fairly efficiently by gravity on Earth. Basically as an analogy "greenhouse gasses" is an unfortunate misnomer created by someone apparently ignorant of how greenhouses actually work.

A more accurate analogy:
* Gravity retention of atmosphere Greenhouse glass : retains air heated by contact with soil, drastically slowing the rate of heat loss by convection - the primary thermal channel.
* "greenhouse gasses" IR glazing applied to glass : partially reflects infrared radiation, slowing heat losses due to radiation, as well as gains from IR-band sunlight.

And there's no meaningful analogy at all to the primary mechanism of heat loss in a greenhouse: conduction through the glass. You can't conduct into vacuum.

Re:Dyson Sphere? (1)

Nethead (1563) | about 6 months ago | (#46541251)

For this to work we'd may need to have a "hindmost" central world that was almost all arcologies. Nothing we need to worry about soon. I mean, I've been to Montana.

Better way (1)

aralin (107264) | about 6 months ago | (#46541223)

I've got a better way, lets release some greenhouse gases, trap the heat until the oceans boil, reuse old steam engines. WIN!

Re:Better way (1)

Nethead (1563) | about 6 months ago | (#46541265)

Then we could put steam vents at 90 degree angles and spin the earth faster. The increased spin could then be used to generate power off of the magnetic field of the Van Allen belt.

Profit!

Seems like a bad idea, intuitively (1)

Anonymous Coward | about 6 months ago | (#46541547)

If you're capturing the earth's radiant energy...
Wouldn't you already have needed to solve the climate change problem?
Because this seems guaranteed to cause manmade global warming - that thermal radiation never escapes, we're harvesting the energy which creates heat...

Re:Seems like a bad idea, intuitively (2)

Hognoxious (631665) | about 6 months ago | (#46541607)

We'll just use some of the energy to run giant refrigerators.

Sheesh, it's tiring doing all the thinking.

Re: Seems like a bad idea, intuitively (0)

Anonymous Coward | about 6 months ago | (#46542615)

Nope,heaters,elimination of the suns energy would kill all living things on the surface of the planet. Just a minor drawback. So maybe a superlarge freezer in the basement, and a sub basement to live in.

why not photovoltaic ? (0)

Anonymous Coward | about 6 months ago | (#46541227)

And how is this supposed to be more efficient and financially better than traditional photovoltaic ?

Re:why not photovoltaic ? (1)

American Patent Guy (653432) | about 6 months ago | (#46541289)

No. It's supposed to work day AND night. That's its advantage.

Re:why not photovoltaic ? (0)

Anonymous Coward | about 6 months ago | (#46541319)

Solar works night and day ... just not in the same places

Re:why not photovoltaic ? (0)

Anonymous Coward | about 6 months ago | (#46541367)

Yup. At day photovoltaics uses daylight and at night it uses nightlight.

Re:why not photovoltaic ? (0)

Anonymous Coward | about 6 months ago | (#46541379)

The idea of these energy sources is not that you pick one of them and forgo the others, but that you use multiple renewable sources in tandem. It doesn't (really) matter how efficient A is compared to B.

Re:why not photovoltaic ? (1)

WaffleMonster (969671) | about 6 months ago | (#46543671)

It doesn't (really) matter how efficient A is compared to B.

In the real world it (really) matters how much each option costs. Given use of term "nanofabrication" and lack of available energy density likely this costs more than anyone is willing to pay into foreseeable future.

The answer: (1, Interesting)

Anonymous Coward | about 6 months ago | (#46541259)

No!

Re:The answer: (0)

Anonymous Coward | about 6 months ago | (#46541391)

I would say "no" to this too. I am fine with the way the world operates right now. Bringing new technological advancements only unnecessarily breaks the way we are used to doing things.

Re:The answer: (1)

JWSmythe (446288) | about 6 months ago | (#46541417)

Actually, the answer is "yes", but isn't very efficient. It sounds like he's stumbled upon the idea of peltier coolers (or TEC). It could convert the released heat energy into electricity. It would work great, if we could build a wall roughly the size of the planet. :)

Just get (1)

rossdee (243626) | about 6 months ago | (#46541293)

Just get Congress to abolish the Laws of Thermodynamics

Re:Just get (0)

Anonymous Coward | about 6 months ago | (#46541837)

...well, eh - are they not still occupied with the simplification of the value of Pi ?

Re:Just get (0)

Anonymous Coward | about 6 months ago | (#46541953)

Look, I've told you before, it's very very important that we get it right. Is it 3 or 4 - you can't rush a question like that.

Re:Just get (0)

Anonymous Coward | about 6 months ago | (#46544201)

I might expect a decision following the Paris(F) administration's initiative for the environment: 4 on even days, 3 else...with Pi=12 on Feb, 29th

Re:Just get (0)

Anonymous Coward | about 6 months ago | (#46543011)

They did already. It happened under the "Patriot Act"

pure spindoctored BS (-1)

Anonymous Coward | about 6 months ago | (#46541309)

yep, BS in the extreme.

What are these people smokin?!

Re:pure spindoctored BS (0)

Anonymous Coward | about 6 months ago | (#46541421)

Exactly. A bachelor's degree is not sufficient for people working in this kind of sophisticated project.

By rule (2)

WinstonWolfIT (1550079) | about 6 months ago | (#46541323)

No.

Not New (4, Informative)

Urgelt . (3586487) | about 6 months ago | (#46541349)

This is not a new idea. http://web.mit.edu/newsoffice/... [mit.edu]

a photovoltaic cell converts light into electrical (1)

Anonymous Coward | about 6 months ago | (#46541383)

a reverse photovoltaic cell converts electrical current into light, i.e. a light bulb!

Is this a case of stupid journalism?

Re: a photovoltaic cell converts light into electr (1)

ewanm89 (1052822) | about 6 months ago | (#46541993)

Partly though thermovoltaic cells do exist.

Cue the bad sci-fi movies... (1)

Improv (2467) | about 6 months ago | (#46541439)

It'd be amazing if there were a hollywood blockbuster that theorises that doing this will make the Earth run out of rotational energy and fall into the Sun.

Re:Cue the bad sci-fi movies... (1)

VortexCortex (1117377) | about 6 months ago | (#46542117)

That's kind of what happened to my machine-planet powered by the tidal forces of its moon. It eventually just slung the moon away.

In a simulation of course. There's no sentient machine race monitoring this planet's technical progress. Nope, this isn't a violation of any galactic statutes (not like I wouldn't need a vacation if it were though).

Re:Cue the bad sci-fi movies... (1)

blueg3 (192743) | about 6 months ago | (#46542215)

Orbital energy. Or, you know, just forward motion.

Rotational energy maintains the night/day cycle.

Re:Cue the bad sci-fi movies... (1)

Farmer Tim (530755) | about 6 months ago | (#46543631)

You obviously have axes to grind...

Reverse photovoltaics exist (0)

Anonymous Coward | about 6 months ago | (#46541461)

They are called LEDs.

Faster Maxwell Daemon (0)

Anonymous Coward | about 6 months ago | (#46541535)

Higher frequency = higher energy, I suppose this is why infra-red capture beats radio-wave capture for energy harvesting. As TFA states, the primary hold up is getting diodes that can switch fast enough (multiple THz) to rectify the captured signal. It's probably better to stick to visible-light capture via PV, way higher energy density there.

moD do3n (-1)

Anonymous Coward | about 6 months ago | (#46541565)

house... pathetic. llok at your soft, guests. Some people ass of them all, We don't sux0r as *BSD has lost more plainly states that Some intelligent Here, please do

thanks harvard (0)

Anonymous Coward | about 6 months ago | (#46541601)

Seriously. Capture the heat that is escaping our planet? Wow. Why don't you go to Iceland and learn what geothermal energy is instead of wasting our time. Oh yeah, and the least slashdot can do is fix the thorn in beta!

Yes (1)

The Cat (19816) | about 6 months ago | (#46541791)

We've been told for years there is no such thing as perpetual motion. Except the moon's orbit is a perpetual motion machine.

We could have tidal energy that is renewable forever. We could have solar-powered desalination. We could have wind power without the windmills. We could have convection energy by building hydrogen recapture machines in the deserts.

For man to sit under the sun and cry about energy shortages must be highly amusing to the intelligent life in and out of the universe.

like reverse polarity on our new toilet turbine? (0)

Anonymous Coward | about 6 months ago | (#46541861)

flip a switch & radio activated poop starts flying everywhere? what a gig...

Very useful ON THE MOON (1)

wisebabo (638845) | about 6 months ago | (#46541867)

Ok, even if this is just marginal on earth (because of the low temperature gradient due to the atmosphere), it should be GREAT on the moon.

During the long lunar night when temperatures drop hundreds of degrees, it should be much easier to generate significant power from the still warm lunar soil. Coupled with the solar power from the long lunar day, it should make long term lunar exploration much more feasible (and prevent problems like the shutdown of "Jade Rabbit" due to freezing).

Re:Very useful ON THE MOON (2)

Overzeetop (214511) | about 6 months ago | (#46541969)

I'm not sure this is actually going to get you that far. The difference in radiant flux (moon vs sun) is T^4, so you're talking about a 200-300K source vs a 6000K source, or (if I inverted correctly) about 8.7mW per m^2 power at 100% efficiency, compared to 1400W/m^2 of solar.

To help Jade Rabbit "not freeze" would have required (?) an acre of array, I'm guessing. It would have been better to use a deployable MLI canopy as a secondary shield against the radiative losses to space and capture the heat directly from the ground under the rover. Again, not that it would help much as you're then prevented from moving except within the canopy.

Scientists love their hammer (1)

Jmc23 (2353706) | about 6 months ago | (#46542671)

So basically they're proposing an extremely inefficient, extremely expensive, tech heavy, and impractical solution to recapturing a tiny fraction of that energy.

Or you know, we could just use the basics of passive solar heating. Capture the sun's energy with a large thermal mass and then use the concentrated energy.

I don't know, covering a quarter of an acre of land to heat my place, or some nice statues inside the greenhouse half of my dome with passive piping to a large thermal mass underground. One of them just sounds nicer and less expensive and less of a drain on the planets resources and it extends my growing season and zone.

Suburban rooftops (1)

Applehu Akbar (2968043) | about 6 months ago | (#46542739)

Bedouins used to make ice by leaving shallow pans of water open to the desert night air, with a blanket under the pan to keep the heat of the ground from soaking into the water. This idea is essentially using a thermocouple in place of the blanket and exploiting the temperature differential to generate electricity.

Can we dream of suburban rooftops that harvest photoelectric power by day plus whatever small amount of back-seepage of heat into the air can be reclaimed at night?

Runaway heating (1)

bluefoxlucid (723572) | about 6 months ago | (#46543477)

So, the earth is too hot. It absorbs energy, and then radiates it away. It reaches an equilibrium so it maintains a cyclical average temperature.

So you want to capture the radiating energy and release it on the earth?

Do you see a problem here?

Source temp is 300K. Carnot efficiency is zero. (1)

140Mandak262Jamuna (970587) | about 6 months ago | (#46543547)

Earth is emitting energy in the 300K temp range. Sun is emitting at 6000K range. Classical thermodynamics defines the maximum possible efficiency of conversion purely based on source and sink temperatures. With earth emitting at 300K which is nearly the ambient, where are we going to find a sink? The sun/earth ratio is 6000/300 = 20. To get the same efficiency as the present solar collectors, you need a sink at 15K.

For all this theoretical work, we could think of putting a huge thermocouple with one end in deep space pulled up by the space elevator. Hey! Let us build the space elevator using two different metals and the rungs using non conducting material. Dual project both space elevator and a space thermocouple! It is totally useless except may be it can sell one more issue of Popular Mechanics with cool graphics.

Solar Panals & Global Warming. (1)

Kaenneth (82978) | about 6 months ago | (#46544881)

My understanding (based on a youtube video I saw once...) is the photovoltaic cells don't capture all the energy of the photons that strike them.

They absorb some energy, converting the visible wavelength photons into infrared wavelength photons.

My question is, does this basically create heat pollution, which is trapped by CO2; while if the same area were covered by white/mirror surface, more energy would exit the atmosphere into space?

How about photocells that convert UV light into energy, and give off visible light (like Florescent materials, that also produce electricity...)?

Applied To ..... (1)

theManInTheYellowHat (451261) | about 6 months ago | (#46545901)

If this could be applied to my checking account I might be able to pay for my kids education before they graduate!

If it was applied to my weight I would loose the weight of the snack before it hit my stomach!

Hair loss could be a thing of the past?

Next up: capturing fuel in auto exhaust (0)

Anonymous Coward | about 6 months ago | (#46545905)

Um... why not capture more of the Sun's energy on the way *in*, instead of suffering through the lossy process of absorption and re-emission? This sounds like the opposite of "blowing your own sail".

And some environmentalist proposed this? (1)

MouseTheLuckyDog (2752443) | about 6 months ago | (#46546885)

So the idea is to trap infrared for energy. But infrared is effectively heat ( crudely spoken ). So you are trapping heat. Doesn't that add to global warming?

This is why people look down on environmentalists.

But what about... (0)

Anonymous Coward | about 5 months ago | (#46550321)

Given were all concerned about global warming and that the ultimate form of energy is heat, it seems a little silly to reintroduce "heat" that is escaping from the atmosphere back into the atmosphere.

Whilst clever, I don't think this is a particularly good idea in the big scheme of things.

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