h a l f b a k e r yBunned. James Bunned.
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Energy by cooling
Extract energy from the cold of space and counteract global warming as a side effect | |
Earth is around 300 degrees Kelvin. Space is around 3 degrees Kelvin. Run a heat engine from this heat difference, and you extract energy and simultaneously cool down the planet.
The hot side is easy. Run the waters of a reasonably warm ocean through a heat exchanger. The larger it is, the more efficient
it is going to be - in transferring heat. The larger it is, the more inefficient it is going to be - in wasted energy pumping fluid around. You, or at least those of you who care about such mundane things as putting ideas into practice, can draw two pretty graphs and find the point where the two curves meet - that is going to be the optimum heat exchanger size on the hot side.
The cold side is more difficult. There is nothing there. The heat has to be radiated away. So you need an efficient radiator.
As an aside, there are things inside most cars called "radiators". Misonomer. They should really be called "liquid-air heat exchangers". The heated water from around the engine cylinders is passed through pipes in intimate contact with metal plates and air is blown past these plates. At the temperature at which these devices operate, below (or just at) the boiling point of water, the dominant mode of heat transfer is by conduction to the large amount of air being blown past, partly by the movement of the automobile and partly by a fan either driven by a belt from the engine or electrically, on demand.
So, at the cold side, you need something of the opposite kind. It has to radiate away heat to the cold space, and at the same time not accept heat from the warm^h^h hot air around it. It would evidently be a "clear weather" device because clouds would obscure the cold sky, instead reflecting the hot earth.
So as not to gain heat by conduction from the surrounding air, it will have to be relatively small and yet efficient. For a heat exchanger, the efficiency may be measured by the temperature drop per unit of heat transferred - degrees per watt - the smaller this is, the more efficient it becomes.
In the search for an efficient radiator of heat, I've come across a halfbaked idea on the subject - IKECE by Vernon. Those of you who have scrolled this far will now realise why this idea is so long. Bear with me, it is going to get longer still.
Now, if you can get a reasonably large temperature difference across your heat engine it will generate energy. The efficiency of energy conversion cannot exceed the theoretical maximum given by the temperature difference devided by the temperature of the hot side, all expressed in absolute units (degrees Kelvin). Bung away a generous fifty degrees in the two heat exchangers each, and the temperature difference is still 200. The hot side is around 250. The efficiency is a respectable 80%. Allowing for the fact that our most efficient engines only approach about 30% efficiency this allows for an overall efficiency of about 24%. About a quarter. You will need to radiate away about four Megawatts of heat to generate each Megawatt of electricity, and you will be cooling the planet as a welcome side effect. Implemented in a large enough scale, this will cause the polar ice caps to grow and the land area of the Earth to increase. More land can be reclaimed from the sea, and the services of Hollanders well versed in such matters will be in high demand. Not that I know anything about THAT.
So we need a "cold sink". One that will radiate away megawatts of caloric fluid and become only about fifty degrees warmer than the cold space, thus becoming colder than ambient (on earth) by two hundred and fifty.
A highly conducting metal plate is coated with Aluminium Oxide, Al203. Hydrogen neuclei (protons) are embedded a few molecular layers inside by a process of ion implantation. This surface is exposed to Flourine. The Flourine atoms attracted by the positive charged protons stay on the surface, bonded weakly to it, and act as radiators. Thus this surface is a super radiator, more efficient than anything seen before. [Vernon's IKECE stripped off of verbiage and other ramblings.]
I propose that Vernon's IKECE can be made to act as the essential component of a heat engine able to give out unlimited energy and counteract global warming at the same time. Those freon powered spraycans are going to be popular once again.
(??) IKECE
IKECE
As mentioned in the main text. Thanks, [neelandan]! [Vernon, Nov 30 2005]
Inevitable Earth Warming
http://www.enterpri...yDayAfter-Part2.htm
Kinda foofy, but so is the Big Bang and Speed of Light, now. [subflower, Nov 30 2005]
Halfbakery: Cosmic Background Radiation
Cosmic_20Background_20Refrigeration
Also involves radiating heat into space, but uses that directly to cool, skipping the electricity step. [jutta, Aug 03 2006]
[link]
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[DrCurry], you have a point, but it is not quite so bad as you imply. If energy flows from ground to Space, and we extract some of that flow to use, then all we have done is diminished the flow by the amount we have extracted. When we use it it degrades to heat, and once again becomes PART of the overall flow to Space. There is no "pepetual" thing here because if you only consider the energy initially extracted from the flow to Space, the next time it flows in that direction, and we try to extract some of it, we only obtain a fraction of it, just as we obtained a fraction of the original Flow. OK? |
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[neelandan], your abbreviated description of the IKECE radiator is almost right. Fluoride IONS need to "hang out" at the surface of the proton-embedded aluminum oxide. Static electricity between the two keeps the ions hanging out, and it is ions that are supposed to do the work of efficiently converting molecular kinetic energy into radiant energy. |
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Next, I suspect you wrote this to imply an absurdity in the IKECE idea (why else did you claim "unlimited" energy in your last paragraph?), but other than the fact that the IKECE is a gadget needing to be built to see if the theory behind it works, it seems to me that what you suggest here is plausible (but not "unlimited"!). |
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As a test, consider the thermoelectric junction. If wires of two different metals are connected at their ends in a loop (half the loop of each wire), and if one junction is hotter than the other, then electricity will flow in the loop. SO: take two meter-square plates of each the two metals, and bond them so that we have two plates, each a meter-square junction. Now bury one plate a few inches under the surface of a desert somewhere, and lay the other plate on the surface. Connect the plates using appropriate wires:
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(air above the ground)
-------(AL plate bonded to)
-------(CU plate)
(a spacer may be a good idea, holding plate off ground)
(dirt at surface of ground)
-------(CU plate bonded to)
-------(AL plate)
(underground continues)
(connect the aluminum sides with aluminum wire, and the copper sides with copper wire)
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(I should note that I don't know the best pair of different metals to use, to maximize the power generated by a thermoelectric juction. The preceding is just an example, therefore.) |
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AT NIGHT, the surface of a desert becomes quite cool, usually. Heat from the ground radiates into Space through usually-cloud-free air. Here the warm ground surrounds one junction/plate, while the other is exposed and cools. Electricity should flow, and be extractable. Note that in the daytime we could imagine this thermoelectric device working in reverse, as the Sun heats the radiator and electricity flows because the shadowed ground is cooler. However, at the end of the day, the ground would not be as warm as if the radiator had not been in the way, and so the next nights' power availability will be lessened. Perhaps we shouldn't try to extract energy from this system in the daytime, to allow the ground to become as warm as possible (tip the radiator vertical so only its edge faces the sun all day). |
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If the IKECE idea works, that would merely increase the efficiency of the radiator/junction, allowing greater electricity generation. |
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I don't understand IKECE. More's the
pity,
but the rest of this sounds like fun. This
is
a way of dumping low grade heat into
space and making a little on the
bargain.
The infrastructure is horribly expensive,
but I like the payoff. If you were willing
to
forego the geostationary advantages of
the
equator you could build one of these ar
either pole and chill the icecaps. [+] |
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DrC: We want energy. We like energy.
It's the low grade heat that is the
problem. Plus we'd actually be dumping
energy. The amount of high grade
usable energy generated would be small
compared to the heat dumped into
space. |
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Hey now. Leave Canada out of this. |
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Why not build a huge solar sail and float it right in the path of sunlight, an earth visor if you will. |
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Construct trillions of tiny hollow carbon beads, and fill them with nothing. There’s probably a balance between the lift the vacuum would provide, and the strength of the carbon sphere. A tiny amount of hydrogen could be added if a larger sphere was required – just enough to prevent an implosion at sea level. |
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Coat one hemisphere with a layer of atoms that will act as a mirror to IR light, and weight the other hemisphere so that it's heavy enough to keep the ‘mirror’ facing space. |
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Release enough of them, and the result is twofold: carbon could be removed from the air, and then released back as little balloons, thus lowering the levels of this powerful greenhouse gas (CO2), and, the reflective carbon balloons will lower the amount of light reaching earth. |
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May be a problem though: less light = less photosynthesis = more carbon in the air = more contracts for building balloons!! |
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DrC, reby, TIB: The idea is to extract energy. The cooling is just a side effect which might, or might not, turn out to be desirable. |
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//So we need a "cold sink". One that will radiate away megawatts of caloric fluid and become only about fifty degrees warmer than the cold space, thus becoming colder than ambient (on earth) by two hundred and fifty.//
And there's one of the problems. To radiate at a decent rate, you need to get to about 1000K. But your radiator is at 50K. The difference in the heat radiation put out by the two is the ratio to the fourth power, i.e., 50/1000 ^4 = 0.000006. So the power you're radiating away is microscopic.
Another problem is the effective sky temperature is much higher than the effective temperature of space. It's probably not much below freezing, even at night in the desert.
Also, the concept of a 'super radiator' doesn't get you much. There are many materials that radiate at .85 and above, and the best you can do (even theoretically) is with a black body radiator, which has an emissivity of 1.0. |
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[TIB], I must have missed something. Vacuum provides lift? [goes off to experiment with vacuum-packed coffee flying machine] |
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Imagine the energy's like water, flowing from the sun into the earth, and then leaking slowly back into space. You're just going to poke a hole in that dam and put a flywheel on it. |
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Conceptually, it works elegantly.[+] |
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I have a really hard time imagining how you could poke that hole though, in the real world. It's a really long distance and any energy's going to want to leak out over that long a path. |
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If we really could go the distance with an energy pipe, then while we're at it, let's tap directly into the sun sometime too. |
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DrC: Subtitle updated as per your request. |
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ldc: The IKECE is a super radiator. Credit Vernon. I'm waiting for him to provide figures on its theoretical efficiency, because he seemed to be a bit hazy on how to build it. |
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I have one of these in my backyard junk pile. |
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Or maybe its a rusty toaster. |
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//ldc: The IKECE is a super radiator. Credit Vernon. I'm waiting for him to provide figures on its theoretical efficiency, because he seemed to be a bit hazy on how to build it. //
Oddly, neelandan shot down Vernon's IKECE idiocy before, most effectively--"And have fifteen Hawaian witch doctors do things with dolls and pins and images of the eyekeesh all night." |
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More of the same, ldchlr. |
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