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Experimental device generates electricity from the coldness of the universe
- pella 7y ago(research) Full Text : https://aip.scitation.org/doi/10.1063/1.5089783 https://aip.scitation.org/doi/10.1063/1.5089783
- delecti 7y agoSo a thermoelectric generator? Saying this is using the "coldness of the universe" is technically true, but it's a bit of a grandiose way of describing the fact that nighttime is colder than day. It would be pretty neat to harvest the natural nighttime cooling of panels though. https://en.wikipedia.org/wiki/Thermoelectric_generator https://en.wikipedia.org/wiki/Thermoelectric_generator
- DEADBEEFC0FFEE 7y agoDoes it perhaps have applications in the Space Industry?
- amelius 7y agoFrom that linked wiki page: > Another application is radioisotope thermoelectric generators which are used in space probes, ...
- notimetorelax 7y agoI don’t think it’s grandiose at all, this TED talk explains the effect pretty well https://youtu.be/7a5NyUITbyk https://youtu.be/7a5NyUITbyk Radiative cooling functions both during night and day.
- satori99 7y agoNot sure if it is mentioned in the video you linked, but a Stanford team has been doing interesting research into this type of thing in recent years; https://news.stanford.edu/2017/09/04/sending-excess-heat-sky/ https://news.stanford.edu/2017/09/04/sending-excess-heat-sky... https://www.technologyreview.com/s/532826/material-cools-buildings-by-sending-heat-into-space/ https://www.technologyreview.com/s/532826/material-cools-bui... http://web.stanford.edu/group/fan/ http://web.stanford.edu/group/fan/
- jessriedel 7y agoNo, this doesn't rely on the nighttime being colder than daytime. So long as you were using a wavelength in which the atmosphere is transparent, you could run the same system at any time of day even if you were in a temperature-controlled bubble that had no daily heat fluctuations. The only reason this system operates at night is because the atmosphere is not actually transparent to the frequencies used; during the day, the sky is just too hot to use as a cold sink.
- Retric 7y agoThat’s close to the same energy solar panels should produce from starlight. So, hard to find a useful application.
- owenversteeg 7y agoYeah, I don't understand why they mention that as the main application, there are a ton of far more impressive and important applications I can imagine off the top of my head if they can improve efficiency.
- leshokunin 7y agoWhat would be those applications?
- RIMR 7y agoRenewable energy generation above the arctic circle during winter?
- Retric 7y agoSystem is even worse in a cold environment.
- cypherpunks01 7y agoWhat about improving refrigeration?
- RIMR 7y agoThey also said that theoretically they should be able to generate one million times more wattage given improvements to the design. Sure, it'll be 25-50 times less efficient than solar power, but it's certainly something. Maybe we could make double-sided solar panels: One for the daytime, one for the nighttime. 4 microwatts per square meter is pretty useless. 4 watts per square meter is a breakthrough.
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- inflatableDodo 7y agoI've thought of trying this before with a toy sterling engine and a tinfoiled satellite dish. You can make ice that way when the air temp is up to 9 or 10 celcius if you put a shot glass of water in polystyrene foam with an opening at the focal point of the dish.
- TheSpiceIsLife 7y agoWait what? Wouldn’t the infrared reflectivity of the parabola concentrate heat energy in to the focal point?
- inflatableDodo 7y agoYou point it at an empty patch of sky. edit - have a go at pointing an infrared thermometer at an empty patch of sky on a clear night.
- TheSpiceIsLife 7y agoOh, right, I understand now, thanks.
- inflatableDodo 7y agoI love radiative cooling. When you first realise what the hell is going on, it is one of those 'aha' moments of real deeper appreciation of a subject.
- duckymcduckface 7y agoMy favorite demo is an electric stoves, turn it on and stare at it from a point along the plane that it's on and you start to marvel at how much heat can be transferred by radiation.
- TheSpiceIsLife 7y ago
- p1mrx 7y agoGood thing the universe is expanding, or else the void would be overflowing with photon waste from projects like this.
- inflatableDodo 7y agoPerhaps that's why it is expanding.
- jacobush 7y agoOh... messing with the ontology. I like it.
- inflatableDodo 7y agoWe'll probably find out eventually that the whole cosmic accelleration thing is a side effect of the use of FTL drives by advanced civilisations. edit - with pan-galactic tickets getting a little bit more expensive every visit.
- TeMPOraL 7y agoBetter than (minor spoiler for Cixin Liu's Three Body Problem trilogy) finding out that the universe used to have many more dimensions, but in some past wars, dimensionality reduction weapons were used.
- inflatableDodo 7y agoI just like the idea that somewhere out there in the universe, there is a minor business envoy to the q'Zickl floating in a waiting lounge, complaining that 'There's much less tentacle room these days than there was a millennia or two ago when hopping business class to Miami. Yes, that Miami, the one in the Horsehead Nebulae. I know, they've made the shuttle smaller due to the greens regulating inertial mass per passenger again. I'd feed those greenshifters to unts.'
- Florin_Andrei 7y agoSo they're cooling the Earth to make energy. You could imagine a dystopian sci-fi novel where "at the end of times" the only source of energy available is this - slowly leech heat out of your planet to make some energy. Decisions, decisions...
- jessriedel 7y agoI don't think you need to increase the heat flow to capture the free energy? If I find a hot bath that is just haphazardly dumping heat into a cold bath, increasing entropy unnecessarily, it's perfectly possible for me to stick a heat engine in between them and capture the free energy from that flow (averting entropy creation) without actually changing the heat flow (joules per second) between the baths.
- taneq 7y agoI've always wondered if some far future civilisation grappling with the heat death of the universe will judge me harshly for mixing hot and cold water together just to make warm water.
- pranjalv123 7y agoIsaac Asimov's "The Gods Themselves" has a similar plot point, except one universe is dumping its excess entropy into another.
- AtlasBarfed 7y agoLike... a war with robots where man covers the sky in clouds to cut off their power supply so the robots take the humans for a power supply and simulate 1990s to keep them distracted, while remaining free humans dig into the earth?
- jacobush 7y agoI so hoped the article was about how somehow, someone stumbled upon a null field generator and that it worked.
- dexen 7y ago>slowly leech heat out of your planet It's a gloomy scenario, but we wouldn't run out of the energy too quickly: >Nearly half of the Earth's heat comes from the radioactive decay of materials inside [1] [1] https://phys.org/news/2011-08-radioactive-key-ingredient-earth.html https://phys.org/news/2011-08-radioactive-key-ingredient-ear...
- supernova87a 7y agoThis isn't new. In fact the same authors already started a company called Skycool that was featured here in a story like 2 years ago. It uses a special coated/layered radiative plate that's specially tuned to an atmospheric transparency window to dump heat to the sky. The problem is that where this would be economically viable, you would generally already choose to use solar panels for the electricity -- cheaper and similarly/more efficient.
- Zenst 7y agoWhilst the raw efficiency of peltiers and solar panels weigh in the favour of solar panels - this design just has to point to the sky. Which for some situations, may make it more viable after all. Ships may be a use for this. But then I'm not up to date on the state of play in peltier advances. I've read some fascinating developments in rectenna's, though no efficiency numbers jumping out. But something that could completely change this whole area of electricity generating. Could this design be adapted to any new tech though if something wow around the corner jumps out as being x better than the best peltier. Maybe from what I can tell, but for now it has some niche uses without a doubt, but you won't see them in your neibours back yard or roof anytime soon if ever.
- HillaryBriss 7y agovis a vis global warning, would it be better to just let that energy go out into the universe without harvesting it?
- dwg 7y agoAssuming there is a demand for energy (given) than generating energy to meet that demand (e.g. by burning coal or gas) has a much larger negative impact I would imagine. It's sorta like capturing braking energy. This used to be dissipated as heat but now can be turned into energy which improves MPG and therefore reduces the need for fossil fuels, no?
- HillaryBriss 7y agoThanks. I follow your reasoning. The "if" is key: will humanity just add, or actually substitute, this source of energy?
- gwbas1c 7y agoI always thought someone would make a device that can suck heat out of the air to make electricity. (Kind of like a heat pump, only that it could completely power itself from the heat in the air instead of needing to consume electricity.)
- derekdahmer 7y agoElectricity cannot be generated from ambient heat. There must be a temperature differential.
- gwbas1c 7y agoIs that a physical limitation, like the speed of light? Or is that a limitation of our current knowledge?
- newsbinator 7y agoMaybe one reason we can't detect advanced civilizations is because they're capturing and recycling all their waste heat & waste EM. We could start looking for cold spots that should be warm.
- raverbashing 7y agoCould be. I never bought the whole Dyson spheres idea. A truly advanced civilization wouldn't need that much energy (they would be very efficient), and certainly wouldn't need to "kidnap" a start for that. A single digit percent of the Earth would need to be covered with solar panels with today's technology for our energetic consumption, I don't see why advanced civilizations would need let's say 10% of the energy of a star (let alone need to capture it)
- newsbinator 7y agoOne reason to harness a star might be replicator or transporter technology. It takes a lot of energy to make an omelette. Or a lot more energy to make a person-sized person.
- ajuc 7y ago> they would be very efficient https://en.wikipedia.org/wiki/Jevons_paradox https://en.wikipedia.org/wiki/Jevons_paradox > In economics, the Jevons paradox (/ˈdʒɛvənz/; sometimes Jevons effect) occurs when technological progress or government policy increases the efficiency with which a resource is used (reducing the amount necessary for any one use), but the rate of consumption of that resource rises due to increasing demand.[1] > In 1865, the English economist William Stanley Jevons observed that technological improvements that increased the efficiency of coal-use led to the increased consumption of coal in a wide range of industries. He argued that, contrary to common intuition, technological progress could not be relied upon to reduce fuel consumption.[4][5] With enough energy crazy things are possible. Terraforming planets, human-lifespan interstellar travel, swarms of space habitats allowing everybody to have their own ecosystem changing to their will. Assuming people won't do it because they don't do it now (when energy is limited) is unwise. Don't you think some rich people would like to have their own space habitat where they can change gravity, day-night cycle, and the whole ecosystem at will? It's possible with current technology, just very expansive. It creates new real estate from scratch. With enough energy everybody could have one. I don't see any point at which people decide "this is enough". Always there will be some people that want more. BTW I agree it won't be a Dyson sphere, it will probably be a Dyson swarm. Much easier to start, cheaper, and has all the benefits of a sphere.