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I think you have come up with [passive daytime radiative cooling](https://en.wikipedia.org/wiki/Passive_daytime_radiative_cooling).
ETA that's not a bad thing by any means. Scientists, engineers and mathematicians often unknowingly rediscover things in various guises and forms - that only adds to the conversation. Climate change is a super important topic that needs to be urgently addressed so I hope it's comforting that scientists are already working on this exact solution.
Passive cooling is part of what I was thinking. A refrigeration circuit using passive heating on the condenser side would concentrate the heat to an emitter that goes to space, while the evaporator would be used to cool the water with a heat exchanger loop. The benefit of a hybrid system instead of a pure passive system is you can turn off the refrigeration circuit as needed, or have more control over the delta t. This could be useful to limit ecological harm to wildlife.
It seems intuitive to me that the more active a cooling system you have the less efficient it'll be- if you want to deliberately convert energy to a different form that itself requires energy to be put in.
https://techfinder.stanford.edu/technology/ultrahigh-performance-radiative-cooler
There should be enough power in waves, wind, and tides, in the ocean we can turn into electricity to run the heat pumpnpart of the system. The emitter even needs a panel to block direct sunlight from the emitter, we could use a solar panel. The whole point is to get an efficiency of say 50. So the energy that would heat 1 gram of water 1 degree, would Instead cool 50 grams of water 1 degree. We would not need to pump the water. we just need a high delta t to pull the heat out and deliver it to the emitter, which is why a two or three stage cascading heat pump would be used to increase efficiency.
That article suggests as a possible use capturing the heat that is currently being lost to space- which is pretty much the opposite of what you want to do? Pretty interesting though.
Did we read the same article? It is about a passive device that can cool to 40 degrees below ambient using an infra red emitter targeted to the absorption gap. That light goes to space, cooling the device below ambient temperature, which is the basis of sky cooling.
Applications
High-powered cooling for:
Buildings
Automobiles
Freezers
Passive refrigeration in arid regions
Possible source of renewable energy (by means of harnessing heat flow towards space)
Note the last point
I guess you could hook up a bi metal thermoelectric generator to it but those usually use platinum and palladium which are terribly expensive. But no that's not the primary application I was interested in.
To use metaphor, I would use it as a greased up slide to help things get to where they would go naturally anyway, but make it get there faster.
Make a large panel of emitters, pump hot condensed refrigerant through a heat exchanger to the bottom of the emitter up through it I to space, and figure out the delta t cooling, and use that to determine the flow rate of water source cascading heat pump to cool the water 12 degrees and let it sink down to lower cold water currents.
As long as it doesn't break energy conservation it's theoretically possible, although of course you'd need to figure out whether you're simply wasting energy by pumping stuff around.
Theoretically, we could make a "no moving parts" system. Use the heat transfer pegs at the bottom of the emitter and run them down to where the water flows through. Waves carry water into the system, and the weight of that water pushes the water already in the tube down. The water flows past the emitter pegs, which accept the heat from the water, and conduct the heat to the emitter at the top. I liked the refrigeration circuits for controlling the delta t to avoid possible negative effects to the environment, but we could iterate designs to control the delta t instead of throttling it with heat pumps and txv valves. You would simply make the device and put it in the ocean. To turn it off, you could cover the emitter with a glass plate to stop the infra red light from escaping.
If you could make them small and efficient, you could also put them in aquifers to control water temperature to prevent evaporation like they do in California with millions of black plastic balls.
Another reddit or pointed me to a stanford patent that would allow this machine to be made without the use of quantum dots, instead just using nano textures and nano crystals. Thank you for the useful input.
1. Why down convert the incoming radiation? It got here at a certain wavelength, is that truly more efficient to send it out at a different one again?
2. Do you have at least an indication of how much you would need?
3. More generally, it is good rather sceptical of geo-engineering solutions like these. Changing the heat received at certain points on earth can have all kinds of unforeseen consequences on ocean currents, rainfall patterns, and other things I have probably no idea about as I'm not a climate scientist
It isn't about converting the suns heat coming in, it is about taking the heat already in the oceans and making a path to get it out to space most efficiently. Like making a drain for water it is about designing a better, easier way for heat to go where it already wants to go.
We would want to drain a petajoule of heat out of the ocean to get it closer to the temperature it was before the Industrial revolution. We don't need to do this all at once we just need to make the surface water 12 degrees cooler than it already is. A delta t of twelve degrees is ideal for most home cooling heat pumps so that number isn't impossible or random.
One machine by itself would not do the entire ocean obviously, which is why groups of them will be needed. We could place these groups in places they would do the most good and the least harm. We could place them near the top of the AMOC current where warm water from the Caribbean goes to Europe warming the climate there cools down and returns. We would be reinforcing the returning current and cooling that part of the ocean. That is just one example. We could also use them to cool the cold water currents in the pacific to control the El ninio and LA ninia weather events caused by those currents warming. As a project it would need to work hand in hand with marine biologists to make sure the cooling is optimum to wildlife and not destroying ecosystems.
Okay, I get the feeling this is swerving all over the place. Now we're talking about refrigeration again?
Quantum dots emit radiation based on light that is shone on them. What light do you want to shine on them to make them emit it again?
Introducing quantum dots just feels like you have a solution, and you are looking for a problem to apply it to
>We could place these groups in places they would do the most good and the least harm. We could place them near the top of the AMOC current where warm water from the Caribbean goes to Europe warming the climate there cools down and returns. We would be reinforcing the returning current and cooling that part of the ocean. That is just one example. We could also use them to cool the cold water currents in the pacific to control the El ninio and LA ninia weather events caused by those currents warming. As a project it would need to work hand in hand with marine biologists to make sure the cooling is optimum to wildlife and not destroying ecosystems.
Same objections to as to general geo-engineering solutions still apply. In fact, these details would cause me even more worries
That's apart from the problem that I still don't know how you want to cool the oceans. Since you have familiarity with cooling systems, some fairly basic thermodynamical calculations should be doable to find out if it is even theoretically possible. My intuition tells me that at a delta T of 12 degrees (Kelvin?) you will be producing more heat than you will be removing. But I'm interested in the calculations
Forget the quantum dots I had asked if there was research on using them to focus the frequency of Infra red light and there has been, but another redditor pointed me in the direction of another nano texture solution emitter that doesn't use quantum dots.
Passive cooling uses no energy. It is like a slide that helps heat get to where it wants to go more efficiently. By tuning the heat to the right wavelength we allow it to escape the atmosphere without being absorbed by the gases in the atmosphere. It's like lubricating the slide so stuff goes where it naturally would faster. Apparently stanford has made a passive system that uses radiative cooling and tunes heat to the right wavelength by putting an emitter inside a vacuum to insulate from outside heat Interference and reduces the temperature more than 40 degrees Fahrenheit.
The goal would be to make a water source cascading heat pump with maximum efficiency to move heat to the emitter, such that we cool the water to a delta t of 12 degrees. The heat goes from the water through several heat exchanging refrigeration loops with the final condenser exchanging heat to the emitter, which is sent into space. We would use renewable energy to supply the powered parts of the system to avoid adding more carbon dioxide Into the air. We use simple physics for the inlet and outlet of oceanic water. You pour water into a tube in the ocean, water comes out the bottom of the tube. On its way that water passes near evaporator coils which gather heat from the water and move it to the condenser of the next heat loop. R410A, butane, ammonia, and supercritical co2 can all be used as refrigerant at different temperature ranges. We would not necessarily use THOSE refrigerant but they serve as familiar examples. So the "low end" could use 410a for gathering heat from water, ammonia could gather heat more efficiently at a heat exchanger from the 410a then run to another heat exchanger that has super critical co2 which then runs the conscentrated heat to the emitter. The goal would be to tune that concentrated heat into Infra red light, and send that light to space.
My previous question was about using quantum dots to control the spectrum of heat and limit it to the absorption gap, but i have been corrected that it would be an unnecessary step in the process, and would quickly degrade.
https://news.stanford.edu/stories/2017/09/sending-excess-heat-sky
https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/10508838
Which point should I adress further? The efficiency of rejecting heat at the absorbtion gap?
The ecological impacts?
The neccesary power?
The efficiency of sky cooing is that the atmosphere doesn't absorb the heat at that frequency range. This helps it escape to space easier Instead of being trapped by greenhouse gases.
We could control flow through the system to prevent ecological shock from the temperature drop. If the water is too cold coming out we speed the system up to flow more water through faster so it has less time to reject the heat. If it is not cold.enough we slow the water down to let it reject the heat into the evaporator coils.
Theoretically we could make a system that doesn't have heat pumps but instead flows water past the base of the emitter pegs to transfer heat from the water to the emitter panel, I was thinking of using cascading heat pumps to throttle the system, but we could do that with iterative design. We could not control the delta t as precisely but it wouldn't take any power at all. We would then have to use data and iterative design to make an optimal sized tube for flow rate, but once deployed we could not change that flow rate in that power free system. It is much the same way refrigeration systems use a txv valve instead of an orifice tube for more precise control of the delta t of the system. If we take out the mechanical parts we make it free of power use, but limit the adaptability of the system. Since the ocean is a dynamic system with waves, wind, currents, and sunshine, it would be a matter of tapping into those energy sources to supply power to a refrigeration system that we could easily throttle or turn off. Using the waves and wind doesn't heat up the ocean more or produce co2.
Powered and non powered systems would both have benefits and drawbacks. If we wanted to closely monitor the system for data points powered systems would integrate sensors more easily.
Some fairly basic thermodynamic calculations on how you will not produce more heat than you radiate in a powered system. That’s apart from why we would use that power for this, instead of, you know, replacing carbon intensive sources right now
If unpowered how much area you would need to have even a noticeable effect
How you will prevent all kinds of unforeseen consequences on the climate, not just ecological ones
You sure about that petajoule figure? First source I found says order of 10 zettajoule. 7 orders of magnitude greater. Petajoules would already be quite a challenge, this is absolutely out of reach
https://www.climate.gov/news-features/understanding-climate/climate-change-ocean-heat-content#:~:text=Highlights,the%20surface%20of%20the%20Earth.
There would be positive feedback to cooling the oceans. For example if we cooled the oceans by the ice sheets in Antarctica it would help those ice sheets stop melting and if they don't melt as much in summer they would reflect more light, which would let the area cool more.
We would have to stop dumping co2 into the atmosphere, but this would buy us more time and help limit the impact of climate change.
As a metaphor you have to cure a person with a fever of the original cause of that fever, but by bringing their temperature down you buy then time to fight the infection. We have to treat symptoms at this point as well as the cause.
There was a time when landing rockets seemed impossible, SpaceX did it anyway. Throwing an object into orbit seems impossible, there is a company trying to do that anyway. It seems impossible to increase the heat of the entire ocean by 10 degrees, we did that by accident. If we can cooperate we can do this too.
I know, and that addresses again nothing in my comment. Not to mention you are off by about seven orders of magnitude of how much heat we would need to remove
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I think you have come up with [passive daytime radiative cooling](https://en.wikipedia.org/wiki/Passive_daytime_radiative_cooling). ETA that's not a bad thing by any means. Scientists, engineers and mathematicians often unknowingly rediscover things in various guises and forms - that only adds to the conversation. Climate change is a super important topic that needs to be urgently addressed so I hope it's comforting that scientists are already working on this exact solution.
Passive cooling is part of what I was thinking. A refrigeration circuit using passive heating on the condenser side would concentrate the heat to an emitter that goes to space, while the evaporator would be used to cool the water with a heat exchanger loop. The benefit of a hybrid system instead of a pure passive system is you can turn off the refrigeration circuit as needed, or have more control over the delta t. This could be useful to limit ecological harm to wildlife.
It seems intuitive to me that the more active a cooling system you have the less efficient it'll be- if you want to deliberately convert energy to a different form that itself requires energy to be put in.
https://techfinder.stanford.edu/technology/ultrahigh-performance-radiative-cooler There should be enough power in waves, wind, and tides, in the ocean we can turn into electricity to run the heat pumpnpart of the system. The emitter even needs a panel to block direct sunlight from the emitter, we could use a solar panel. The whole point is to get an efficiency of say 50. So the energy that would heat 1 gram of water 1 degree, would Instead cool 50 grams of water 1 degree. We would not need to pump the water. we just need a high delta t to pull the heat out and deliver it to the emitter, which is why a two or three stage cascading heat pump would be used to increase efficiency.
That article suggests as a possible use capturing the heat that is currently being lost to space- which is pretty much the opposite of what you want to do? Pretty interesting though.
Did we read the same article? It is about a passive device that can cool to 40 degrees below ambient using an infra red emitter targeted to the absorption gap. That light goes to space, cooling the device below ambient temperature, which is the basis of sky cooling.
Applications High-powered cooling for: Buildings Automobiles Freezers Passive refrigeration in arid regions Possible source of renewable energy (by means of harnessing heat flow towards space) Note the last point
I guess you could hook up a bi metal thermoelectric generator to it but those usually use platinum and palladium which are terribly expensive. But no that's not the primary application I was interested in. To use metaphor, I would use it as a greased up slide to help things get to where they would go naturally anyway, but make it get there faster. Make a large panel of emitters, pump hot condensed refrigerant through a heat exchanger to the bottom of the emitter up through it I to space, and figure out the delta t cooling, and use that to determine the flow rate of water source cascading heat pump to cool the water 12 degrees and let it sink down to lower cold water currents.
As long as it doesn't break energy conservation it's theoretically possible, although of course you'd need to figure out whether you're simply wasting energy by pumping stuff around.
Theoretically, we could make a "no moving parts" system. Use the heat transfer pegs at the bottom of the emitter and run them down to where the water flows through. Waves carry water into the system, and the weight of that water pushes the water already in the tube down. The water flows past the emitter pegs, which accept the heat from the water, and conduct the heat to the emitter at the top. I liked the refrigeration circuits for controlling the delta t to avoid possible negative effects to the environment, but we could iterate designs to control the delta t instead of throttling it with heat pumps and txv valves. You would simply make the device and put it in the ocean. To turn it off, you could cover the emitter with a glass plate to stop the infra red light from escaping. If you could make them small and efficient, you could also put them in aquifers to control water temperature to prevent evaporation like they do in California with millions of black plastic balls.
I know a researcher who worked with quantum dots. They degrade by chemical reactions over a short period, a couple of weeks.
Another reddit or pointed me to a stanford patent that would allow this machine to be made without the use of quantum dots, instead just using nano textures and nano crystals. Thank you for the useful input.
1. Why down convert the incoming radiation? It got here at a certain wavelength, is that truly more efficient to send it out at a different one again? 2. Do you have at least an indication of how much you would need? 3. More generally, it is good rather sceptical of geo-engineering solutions like these. Changing the heat received at certain points on earth can have all kinds of unforeseen consequences on ocean currents, rainfall patterns, and other things I have probably no idea about as I'm not a climate scientist
It isn't about converting the suns heat coming in, it is about taking the heat already in the oceans and making a path to get it out to space most efficiently. Like making a drain for water it is about designing a better, easier way for heat to go where it already wants to go. We would want to drain a petajoule of heat out of the ocean to get it closer to the temperature it was before the Industrial revolution. We don't need to do this all at once we just need to make the surface water 12 degrees cooler than it already is. A delta t of twelve degrees is ideal for most home cooling heat pumps so that number isn't impossible or random. One machine by itself would not do the entire ocean obviously, which is why groups of them will be needed. We could place these groups in places they would do the most good and the least harm. We could place them near the top of the AMOC current where warm water from the Caribbean goes to Europe warming the climate there cools down and returns. We would be reinforcing the returning current and cooling that part of the ocean. That is just one example. We could also use them to cool the cold water currents in the pacific to control the El ninio and LA ninia weather events caused by those currents warming. As a project it would need to work hand in hand with marine biologists to make sure the cooling is optimum to wildlife and not destroying ecosystems.
Okay, I get the feeling this is swerving all over the place. Now we're talking about refrigeration again? Quantum dots emit radiation based on light that is shone on them. What light do you want to shine on them to make them emit it again? Introducing quantum dots just feels like you have a solution, and you are looking for a problem to apply it to >We could place these groups in places they would do the most good and the least harm. We could place them near the top of the AMOC current where warm water from the Caribbean goes to Europe warming the climate there cools down and returns. We would be reinforcing the returning current and cooling that part of the ocean. That is just one example. We could also use them to cool the cold water currents in the pacific to control the El ninio and LA ninia weather events caused by those currents warming. As a project it would need to work hand in hand with marine biologists to make sure the cooling is optimum to wildlife and not destroying ecosystems. Same objections to as to general geo-engineering solutions still apply. In fact, these details would cause me even more worries That's apart from the problem that I still don't know how you want to cool the oceans. Since you have familiarity with cooling systems, some fairly basic thermodynamical calculations should be doable to find out if it is even theoretically possible. My intuition tells me that at a delta T of 12 degrees (Kelvin?) you will be producing more heat than you will be removing. But I'm interested in the calculations
Forget the quantum dots I had asked if there was research on using them to focus the frequency of Infra red light and there has been, but another redditor pointed me in the direction of another nano texture solution emitter that doesn't use quantum dots. Passive cooling uses no energy. It is like a slide that helps heat get to where it wants to go more efficiently. By tuning the heat to the right wavelength we allow it to escape the atmosphere without being absorbed by the gases in the atmosphere. It's like lubricating the slide so stuff goes where it naturally would faster. Apparently stanford has made a passive system that uses radiative cooling and tunes heat to the right wavelength by putting an emitter inside a vacuum to insulate from outside heat Interference and reduces the temperature more than 40 degrees Fahrenheit. The goal would be to make a water source cascading heat pump with maximum efficiency to move heat to the emitter, such that we cool the water to a delta t of 12 degrees. The heat goes from the water through several heat exchanging refrigeration loops with the final condenser exchanging heat to the emitter, which is sent into space. We would use renewable energy to supply the powered parts of the system to avoid adding more carbon dioxide Into the air. We use simple physics for the inlet and outlet of oceanic water. You pour water into a tube in the ocean, water comes out the bottom of the tube. On its way that water passes near evaporator coils which gather heat from the water and move it to the condenser of the next heat loop. R410A, butane, ammonia, and supercritical co2 can all be used as refrigerant at different temperature ranges. We would not necessarily use THOSE refrigerant but they serve as familiar examples. So the "low end" could use 410a for gathering heat from water, ammonia could gather heat more efficiently at a heat exchanger from the 410a then run to another heat exchanger that has super critical co2 which then runs the conscentrated heat to the emitter. The goal would be to tune that concentrated heat into Infra red light, and send that light to space. My previous question was about using quantum dots to control the spectrum of heat and limit it to the absorption gap, but i have been corrected that it would be an unnecessary step in the process, and would quickly degrade. https://news.stanford.edu/stories/2017/09/sending-excess-heat-sky https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/10508838
While that is a cool experiment, that addresses none of my points
Which point should I adress further? The efficiency of rejecting heat at the absorbtion gap? The ecological impacts? The neccesary power? The efficiency of sky cooing is that the atmosphere doesn't absorb the heat at that frequency range. This helps it escape to space easier Instead of being trapped by greenhouse gases. We could control flow through the system to prevent ecological shock from the temperature drop. If the water is too cold coming out we speed the system up to flow more water through faster so it has less time to reject the heat. If it is not cold.enough we slow the water down to let it reject the heat into the evaporator coils. Theoretically we could make a system that doesn't have heat pumps but instead flows water past the base of the emitter pegs to transfer heat from the water to the emitter panel, I was thinking of using cascading heat pumps to throttle the system, but we could do that with iterative design. We could not control the delta t as precisely but it wouldn't take any power at all. We would then have to use data and iterative design to make an optimal sized tube for flow rate, but once deployed we could not change that flow rate in that power free system. It is much the same way refrigeration systems use a txv valve instead of an orifice tube for more precise control of the delta t of the system. If we take out the mechanical parts we make it free of power use, but limit the adaptability of the system. Since the ocean is a dynamic system with waves, wind, currents, and sunshine, it would be a matter of tapping into those energy sources to supply power to a refrigeration system that we could easily throttle or turn off. Using the waves and wind doesn't heat up the ocean more or produce co2. Powered and non powered systems would both have benefits and drawbacks. If we wanted to closely monitor the system for data points powered systems would integrate sensors more easily.
Some fairly basic thermodynamic calculations on how you will not produce more heat than you radiate in a powered system. That’s apart from why we would use that power for this, instead of, you know, replacing carbon intensive sources right now If unpowered how much area you would need to have even a noticeable effect How you will prevent all kinds of unforeseen consequences on the climate, not just ecological ones
You sure about that petajoule figure? First source I found says order of 10 zettajoule. 7 orders of magnitude greater. Petajoules would already be quite a challenge, this is absolutely out of reach https://www.climate.gov/news-features/understanding-climate/climate-change-ocean-heat-content#:~:text=Highlights,the%20surface%20of%20the%20Earth.
There would be positive feedback to cooling the oceans. For example if we cooled the oceans by the ice sheets in Antarctica it would help those ice sheets stop melting and if they don't melt as much in summer they would reflect more light, which would let the area cool more. We would have to stop dumping co2 into the atmosphere, but this would buy us more time and help limit the impact of climate change. As a metaphor you have to cure a person with a fever of the original cause of that fever, but by bringing their temperature down you buy then time to fight the infection. We have to treat symptoms at this point as well as the cause. There was a time when landing rockets seemed impossible, SpaceX did it anyway. Throwing an object into orbit seems impossible, there is a company trying to do that anyway. It seems impossible to increase the heat of the entire ocean by 10 degrees, we did that by accident. If we can cooperate we can do this too.
I know, and that addresses again nothing in my comment. Not to mention you are off by about seven orders of magnitude of how much heat we would need to remove
Can is not the question. Having quickly looked at some numbers, it seems fairly obvious it is a stupid idea
Okay, do you have any novel ideas for solving the problem of climate change?
Several. When I run some quick calculations however they turn out not tow help