6 ms·

New technology could reduce the amount of energy for air conditioning

79 points by isaacfrond 2y ago

dan353hehe 2y ago
https://web.archive.org/web/20240717102854/https://www.wired.com/story/cutting-edge-technology-could-massively-reduce-the-amount-of-energy-used-for-air-conditioning/ https://web.archive.org/web/20240717102854/https://www.wired...
initramfs 2y ago
what happened to the DEVAP? https://www.osti.gov/sciencecinema/biblio/1047710 https://www.osti.gov/sciencecinema/biblio/1047710 It appears it's been in development for more than 10 years: https://www.nrel.gov/docs/fy23osti/87527.pdf https://www.nrel.gov/docs/fy23osti/87527.pdf
antisthenes 2y ago
Just pair AC with dirt cheap solar panels and the problem takes care of itself. No need to by hyper-efficient when energy is almost free.
- Feathercrown 2y ago
  It may be cheaper or more effective to increase efficiency rather than offset the efficiency cost with more energy. Plus you can do both!
- HumblyTossed 2y ago
  Make the AC more efficient which means you could potentially run a smaller unit which means fewer solar panels.
- Log_out_ 2y ago
  Cooling storage? Generate a differential ahead of time?
  - dr_orpheus 2y ago
    If you squint at it, this is sort of the premise of a ground source heat pump.
- vundercind 2y ago
  And where are those? Installed cost, I mean. Assume, like in most houses, none of the supporting electrical work has been done for solar already. Where’s the dirt cheap home solar?
- nradov 2y ago
  In much of the world, AC power demand peaks later in the day when solar power supply is minimal or zero. So pairing as you suggest would require a huge amount of storage capacity. Or in some places they could also use high voltage transmission lines to areas further to the west that are still receiving significant sunlight at that time. Energy is only free at times when we don't actually need it.
  - Rayhem 2y ago
    A/C is interesting because it has something of a built-in capacity system. "Super" cool the building during times of the day when power is readily available, and that cooling then persists. You don't have to store the electrical power specifically.
    - nradov 2y ago
      Precooling or supercooling can maybe help a bit in a few areas but it won't make a huge difference in terms of solar power for AC. Most buildings don't have the thermal mass or insulation to gain much benefit. And you can't cool buildings below about 65 °F / 18 °C or else the occupants complain.
- elric 2y ago
  It's wasteful, and that "free" energy could be used for more productive purposes.
- carapace 2y ago
  The second law of thermodynamics would like a word...
tantalor 2y ago
Last episode of Tech Ingredients teased this: https://youtu.be/hc_HcT4pIOE?si=0Nn1HwY-rpvhny9H&t=922 https://youtu.be/hc_HcT4pIOE?si=0Nn1HwY-rpvhny9H&t=922 in the next video we're going to show you how to improve the efficiency of air conditioners and not by a small amount it's estimated that approximately $200 billion a year is used worldwide to generate the electricity that drives air conditioning so even a few per reduction in the cost of running an air conditioner would make a huge difference and could save billions of dollars and what we're going to show you isn't going to improve the efficiency by a small amount but by a huge amount so stay tuned
netcraft 2y ago
I was talking with someone from Greece recently who was experiencing a heat wave and they dont have AC. I am from the south eastern US where we are basically required to have AC for de-humidification as much as cooling - we would be overrun with mold and mildew without AC in the summer. Our heat indexes regularly reach 105F during the summer and sometimes much higher. I joked the other day that if our aquifers ever ran out of water we could probably get most of what we need with just a better dehumidifier. Edit to add: just in case, you should never use water out of a dehumidifier for anything but grey water use cases unless you sanitize and purify it - it can make you very sick!
- jvanderbot 2y ago
  That's not really a joke. Even in Minnesota summers, I pull 2 gallons every couple days out of our basement air. That's enough for me. I've given serious thought to putting a couple outside to capture water for our sprinkler system / gardening irrigation, if it weren't for this year's 100 year rains.
  - ghaff 2y ago
    Yeah, in New England I really need a dehumidifier in the basement. It's a bit damp in any case (old fieldstone) but the dehumidifier keeps it from getting really bad.
  - deleted 2y ago
    [deleted]
- amykhar 2y ago
  It would be cool if they could put some of this technology into commercial grade dehumidifiers even before they get put into HVAC systems. If you could run a super efficient portable dehumidifier and boost the performance of your HVAC system, it would be much faster to reduce overall energy consumption because it would be far less expensive than upgrading an entire HVAC system.
  - vel0city 2y ago
bschwindHN 2y ago
Sorry to comment on the site and not the article, but goddamn. I have an old phone and visiting news sites like wired make it as hot as if I'm playing a video game, and the page had to reload several times like it ran out of memory. I lost 15% of my battery in 2 minutes of reading. Wired (and other news sites), what the hell are you doing to computers? Stop it. People on newer phones may not notice it, but they're still burning just as many cycles on whatever stupid bullshit you decided to add to your site. Maybe we wouldn't need so many air conditioners if sites like yours didn't exist.
- explaininjs 2y ago
  This makes me want an LLM that traces every line of code running on a site and provides a summary… “when you scrolled the page 2 pixels just now, it triggered 500 network requests to various tracking sites. additionally, it forced redrawing the site 3 times, and consumed 400ms of GPU time.”
  - ohthatsnotright 2y ago
    Why on earth would you involve a larger waste of resources to summarize something which is capturable and displayable without?
    - explaininjs 2y ago
      I’m happy to sift through a .cpuprofile and create an intelligent actionable summary of it if I’m at work and that’s the job they’re paying me to do. And very often they do pay me quite handsomely for my ability to do just that! But if I’m not at work, I frankly don’t care enough. A single button “take trade for 1 second and send it to GPT4” is the level of effort I’m willing to freedom dedicate to these folks’ crap.
- tijtij 2y ago
  I have newerish phone and I still run Kiwi Browser with the uBlock Origin extension for this very reason.
- 2y ago
lsaferite 2y ago
I think they alluded to it in the article, but when a heat pump is cooling the inside it's generating lots of heat on the outside. They could/should/likely are using that 'waste' heat to dry out the desiccant. Seems like a great plan. I often wonder why hot water systems aren't linked into the HVAC as well. I know you can get heat pump water heaters, but it seems like integrating it into the HVAC system would potentially allow for system scale optimizations. I would assume the cost/complexity is too much for residential systems. For that matter, refrigeration in homes falls into the same category as they are a heat pump that's dumping waste heat into your living space.
- robnado 2y ago
  Combining refrigerator, water heater and heat pump implies the need for transferring the fluid used as refrigerant between these components. This is usually a gas that is not trivial to contain, so creating this shared pipeline increases the points of failure. Further, you now have to insulate the entire length of this system, using material to do so, and you will end up losing a certain amount of efficiency anyways in this piping system. Also, what if your need in hot water is much greater than your need to cool the house or vice versa, what is your backup system for disposing of heat or cold when not required? It’s not certain that after solving all these problems and others, that you still have a net efficiency gain.
  - alanbernstein 2y ago
    I like to imagine a world where it's acceptable for houses to be designed around a utility room where all of these interchanges, insulation, isolation, exhaust, issues can be contained, and accessed, in a small, separate, space that is not part of the living area.
    - Etheryte 2y ago
      Unfortunately it's also a world where having a problem with your aircon means your fridge stops working and replacing a fridge means calling in a technician for the plumbing.
  - 2y ago
T3OU-736 2y ago
Another trend I have seen[1] ] (US market, high performance/high energy efficiency homes) is the use of HVAC and separate, standalone dehumidifier to do the same thing - take out humidity out of the air that the AC system has to otherwise both cool and dehumidify on it own. The framing (at least as I understood it) was more on the psychometric side - 24C@65% relatuve humidity _feels_ worse than 27C@45%RH, but the energy savings aspect is also non-trivial. As an aside - a fairly large number of central AC systems in the US do not have a humidity censor, so they only go by the temperature set point. Upgrading to control system which does measure humidity, while energy inefficient (because AC would be used to dehumidify the air _below_ the target set point), is an option, though not as good as having a stand-alone humidity control system. Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Probably not cost effective for them. :\ [1] https://youtu.be/rWWLW4nLNBI?si=Ud1jk3x58H6pnMci https://youtu.be/rWWLW4nLNBI?si=Ud1jk3x58H6pnMci
- bob1029 2y ago
  Another option is a variable speed condensing unit. This is what I am looking at doing next. A dedicated central dehumidifier is nice, but I've found them to be kind of noisy, especially when installed in the attic. Its got its own compressor, so the vibrations will transfer into the structure.
- hunter2_ 2y ago
  > Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Same, and the worst part is that Nest already includes a hygrometer to show humidity in the app. All they need to give the user is a toggle: setpoint in regular dry bulb temperature, or setpoint in calculated wet bulb temperature (or heat index or "feels like" or whatever user-friendly calculation). Although their remote temperature sensors don't have a hygrometer, only the main unit.
- kjkjadksj 2y ago
  Part of this is solved by sizing the ac correctly. Too powerful an ac and it doesn’t cycle as often and humidity builds.
- wongarsu 2y ago
habitue 2y ago
Since this article uses that fluffy "tell a story" writing style, here's the facts in the article stripped out: 1. Air conditioning consumes 10% of global energy and 20% of energy used in buildings. 2. Demand for cooling is expected to increase significantly, with 2/3 of world households projected to have air conditioning by 2050. 3. Dehumidification accounts for over half of energy consumption in air conditioners in humid conditions. 4. New technologies are being developed to improve air conditioning efficiency: a. AirJoule by Montana Technologies: - Uses metal-organic framework material for dehumidification - Claims to reduce energy for dehumidification by up to 90% - Still in prototype and testing stages b. Blue Frontier: - Uses liquid desiccant for dehumidification - Being installed in various locations in the US c. IceBrick by Nostromo Energy: - Energy storage system for large-scale cooling - Can reduce annual cooling costs by 30% and associated emissions by up to 80% - Only suitable for centralized cooling systems d. Gradient: - Window-based heat pumps with larger external units for better efficiency - Currently costs $3,800, aiming to reduce to $1,000 5. Electrocaloric cooling is being researched as a potential future technology, potentially 20% more efficient than current methods. 6. Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run. 7. Current non-centralized air conditioners operate at only about 20% of their theoretical maximum efficiency.
- klabb3 2y ago
  > 6. Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run. What about insulation? In my experience the insulation in most hot places is abysmal, compared to cold places. I’m not even a layman, but shouldn’t the physics work the same? Or does the air flow from AC change the equation?
  - cool_dude85 2y ago
    I live in Florida and new-build homes are relatively well-insulated. Older stuff can be anywhere from very poor to surprisingly good (e.g. old, small concrete block housing). And yes, the idea is broadly the same, although insulation doesn't help with de-humidification.
hgomersall 2y ago
In areas where water is not in particularly short supply, you can cool by evaporating water into the exhaust pre-heat-exchanger of an MVHR system. This then vents the warmer humid air into the outside and cools incoming air. The enthalpy diagram suggest it's quite helpful and there's a product on the market that uses exactly this approach. It's basically half of a closed cycle heat pump, in which the hot side is an externality.
- HPsquared 2y ago
  Could that increase the humidity in the surrounding street environment?
- lsaferite 2y ago
  Sounds similar to a swamp cooler.
  - hgomersall 2y ago
    Indeed, but the difference is the high humidity cooled air is used to cool low humidity air, so you don't get the humidity increase inside.
0xbadcafebee 2y ago
We could reduce demand for air conditioning if we designed our lives around the natural environment rather than isolating ourselves from it. Right now we build giant boxes to live/move around in that suck up the sun's heat, then we insulate the box, then build another box to remove moisture in the box, cool the air in the box, blow it around, and then we have to power it... ....or we could live and move around in an open, shaded area, where wind can pass easily, fans blow on us to cool us (your skin is designed for cooling with wind, unlike most other animals on the planet), and cool mists can assist. The latter is how I stay comfortable while camping in 90% humidity and 90F temperature. There are other solutions too, like staying underground during the peak of the heat, taking a dip in a pool of water, drinking cold liquids. All these and more don't require an exponential increase in energy generation, advanced engineering, or boxes designed to create an artificial environment.
JumpCrisscross 2y ago
> The system wouldn’t suit a single house, as it only works with these large centralized cooling installations. However, it can be bolted to a variety of chiller plants—it doesn’t really matter what circulating fluid they use, for example, Ben Nun says We have district heating in New York [1]. Fascinating to think of district cooling, too. [1] https://en.wikipedia.org/wiki/District_heating https://en.wikipedia.org/wiki/District_heating
- kasey_junk 2y ago
  Chicago has district cooling https://wgntv.com/news/chicago-news/the-ice-machine-that-chills-chicagos-skyscrapers-inside-downtowns-district-cooling-systems/amp/ https://wgntv.com/news/chicago-news/the-ice-machine-that-chi...
ninininino 2y ago
Air conditioning should be applied only the to a bubble of cubic space surrounding the people in a given room as well as any temperature-sensitive goods like medicines, perishables, etc. We ought to develop tech to facilitate this, for example a mosquito net style insulating cocoon to enclose your bed at night that conditions the air inside of it but leaves the rest of the room warm.
kkfx 2y ago
Honestly it could be hardly used in practice. The frontier of cooling is: - living in MODERN, so air-tight, well insulated buildings, designed to get the Sun when needed in winter, but not get it in summer with simple design choices etc; -living in places where nights are fresh and having p.v. to cool with no energy consumption from grid during the day. Now the above points are a bit bold but try reasoning why we live where we live. In the past places where circadian thermal delta was/is lower was very good places because it was less hot than now and there was no cheap heating. Similarly living in some places very deep in a valley was nice because floods was a thing anyway, but having clean water was invaluable and homes back then have had much less things who can be damaged by floods. Climate have change but technology, human living is changed much more. In the present world many inhabited parts of the world that back than was nice places, today they are not and others back than not so nice today are nice places. In the past being many in a single places means: - being able to defend against enemies - having access to all professions and services - having trade and learning opportunities - be more exposed to illness, BUT being able to get help much easier now? It means that - 9/11 alike attacks or simple drone attacks are much more easy and deadly - you get more dysfunctional services because we are too dense for them in too many place (as an example packages delivery in large condo complex vs single family homes) - be more exposed to illness, with sometimes even LESS chances of a quick aid - being mostly limited by nearby activities instead of having plenty of space for build a new one and remote work Try to weight this, in terms of opportunities, disasters and who win vs who loose.

79 points by isaacfrond 2y ago

https://web.archive.org/web/20240717102854/https://www.wired.com/story/cutting-edge-technology-could-massively-reduce-the-amount-of-energy-used-for-air-conditioning/ https://web.archive.org/web/20240717102854/https://www.wired...

initramfs 2y ago

what happened to the DEVAP? https://www.osti.gov/sciencecinema/biblio/1047710 https://www.osti.gov/sciencecinema/biblio/1047710 It appears it's been in development for more than 10 years: https://www.nrel.gov/docs/fy23osti/87527.pdf https://www.nrel.gov/docs/fy23osti/87527.pdf

antisthenes 2y ago

Just pair AC with dirt cheap solar panels and the problem takes care of itself. No need to by hyper-efficient when energy is almost free.

Feathercrown 2y ago
It may be cheaper or more effective to increase efficiency rather than offset the efficiency cost with more energy. Plus you can do both!
HumblyTossed 2y ago
Make the AC more efficient which means you could potentially run a smaller unit which means fewer solar panels.
Log_out_ 2y ago
Cooling storage? Generate a differential ahead of time?
- dr_orpheus 2y ago
  If you squint at it, this is sort of the premise of a ground source heat pump.
vundercind 2y ago
And where are those? Installed cost, I mean. Assume, like in most houses, none of the supporting electrical work has been done for solar already. Where’s the dirt cheap home solar?
nradov 2y ago
In much of the world, AC power demand peaks later in the day when solar power supply is minimal or zero. So pairing as you suggest would require a huge amount of storage capacity. Or in some places they could also use high voltage transmission lines to areas further to the west that are still receiving significant sunlight at that time. Energy is only free at times when we don't actually need it.
- Rayhem 2y ago
  A/C is interesting because it has something of a built-in capacity system. "Super" cool the building during times of the day when power is readily available, and that cooling then persists. You don't have to store the electrical power specifically.
  - nradov 2y ago
    Precooling or supercooling can maybe help a bit in a few areas but it won't make a huge difference in terms of solar power for AC. Most buildings don't have the thermal mass or insulation to gain much benefit. And you can't cool buildings below about 65 °F / 18 °C or else the occupants complain.
elric 2y ago
It's wasteful, and that "free" energy could be used for more productive purposes.
carapace 2y ago
The second law of thermodynamics would like a word...

tantalor 2y ago

Last episode of Tech Ingredients teased this: https://youtu.be/hc_HcT4pIOE?si=0Nn1HwY-rpvhny9H&t=922 https://youtu.be/hc_HcT4pIOE?si=0Nn1HwY-rpvhny9H&t=922 in the next video we're going to show you how to improve the efficiency of air conditioners and not by a small amount it's estimated that approximately $200 billion a year is used worldwide to generate the electricity that drives air conditioning so even a few per reduction in the cost of running an air conditioner would make a huge difference and could save billions of dollars and what we're going to show you isn't going to improve the efficiency by a small amount but by a huge amount so stay tuned

netcraft 2y ago

I was talking with someone from Greece recently who was experiencing a heat wave and they dont have AC. I am from the south eastern US where we are basically required to have AC for de-humidification as much as cooling - we would be overrun with mold and mildew without AC in the summer. Our heat indexes regularly reach 105F during the summer and sometimes much higher. I joked the other day that if our aquifers ever ran out of water we could probably get most of what we need with just a better dehumidifier. Edit to add: just in case, you should never use water out of a dehumidifier for anything but grey water use cases unless you sanitize and purify it - it can make you very sick!

jvanderbot 2y ago
That's not really a joke. Even in Minnesota summers, I pull 2 gallons every couple days out of our basement air. That's enough for me. I've given serious thought to putting a couple outside to capture water for our sprinkler system / gardening irrigation, if it weren't for this year's 100 year rains.
- ghaff 2y ago
  Yeah, in New England I really need a dehumidifier in the basement. It's a bit damp in any case (old fieldstone) but the dehumidifier keeps it from getting really bad.
- deleted 2y ago
  [deleted]
amykhar 2y ago
It would be cool if they could put some of this technology into commercial grade dehumidifiers even before they get put into HVAC systems. If you could run a super efficient portable dehumidifier and boost the performance of your HVAC system, it would be much faster to reduce overall energy consumption because it would be far less expensive than upgrading an entire HVAC system.
- vel0city 2y ago

bschwindHN 2y ago

Sorry to comment on the site and not the article, but goddamn. I have an old phone and visiting news sites like wired make it as hot as if I'm playing a video game, and the page had to reload several times like it ran out of memory. I lost 15% of my battery in 2 minutes of reading. Wired (and other news sites), what the hell are you doing to computers? Stop it. People on newer phones may not notice it, but they're still burning just as many cycles on whatever stupid bullshit you decided to add to your site. Maybe we wouldn't need so many air conditioners if sites like yours didn't exist.

explaininjs 2y ago
This makes me want an LLM that traces every line of code running on a site and provides a summary… “when you scrolled the page 2 pixels just now, it triggered 500 network requests to various tracking sites. additionally, it forced redrawing the site 3 times, and consumed 400ms of GPU time.”
- ohthatsnotright 2y ago
  Why on earth would you involve a larger waste of resources to summarize something which is capturable and displayable without?
  - explaininjs 2y ago
    I’m happy to sift through a .cpuprofile and create an intelligent actionable summary of it if I’m at work and that’s the job they’re paying me to do. And very often they do pay me quite handsomely for my ability to do just that! But if I’m not at work, I frankly don’t care enough. A single button “take trade for 1 second and send it to GPT4” is the level of effort I’m willing to freedom dedicate to these folks’ crap.
tijtij 2y ago
I have newerish phone and I still run Kiwi Browser with the uBlock Origin extension for this very reason.
2y ago

lsaferite 2y ago

I think they alluded to it in the article, but when a heat pump is cooling the inside it's generating lots of heat on the outside. They could/should/likely are using that 'waste' heat to dry out the desiccant. Seems like a great plan. I often wonder why hot water systems aren't linked into the HVAC as well. I know you can get heat pump water heaters, but it seems like integrating it into the HVAC system would potentially allow for system scale optimizations. I would assume the cost/complexity is too much for residential systems. For that matter, refrigeration in homes falls into the same category as they are a heat pump that's dumping waste heat into your living space.

robnado 2y ago
Combining refrigerator, water heater and heat pump implies the need for transferring the fluid used as refrigerant between these components. This is usually a gas that is not trivial to contain, so creating this shared pipeline increases the points of failure. Further, you now have to insulate the entire length of this system, using material to do so, and you will end up losing a certain amount of efficiency anyways in this piping system. Also, what if your need in hot water is much greater than your need to cool the house or vice versa, what is your backup system for disposing of heat or cold when not required? It’s not certain that after solving all these problems and others, that you still have a net efficiency gain.
- alanbernstein 2y ago
  I like to imagine a world where it's acceptable for houses to be designed around a utility room where all of these interchanges, insulation, isolation, exhaust, issues can be contained, and accessed, in a small, separate, space that is not part of the living area.
  - Etheryte 2y ago
    Unfortunately it's also a world where having a problem with your aircon means your fridge stops working and replacing a fridge means calling in a technician for the plumbing.
- 2y ago

T3OU-736 2y ago

Another trend I have seen[1] ] (US market, high performance/high energy efficiency homes) is the use of HVAC and separate, standalone dehumidifier to do the same thing - take out humidity out of the air that the AC system has to otherwise both cool and dehumidify on it own. The framing (at least as I understood it) was more on the psychometric side - 24C@65% relatuve humidity _feels_ worse than 27C@45%RH, but the energy savings aspect is also non-trivial. As an aside - a fairly large number of central AC systems in the US do not have a humidity censor, so they only go by the temperature set point. Upgrading to control system which does measure humidity, while energy inefficient (because AC would be used to dehumidify the air _below_ the target set point), is an option, though not as good as having a stand-alone humidity control system. Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Probably not cost effective for them. :\ [1] https://youtu.be/rWWLW4nLNBI?si=Ud1jk3x58H6pnMci https://youtu.be/rWWLW4nLNBI?si=Ud1jk3x58H6pnMci

bob1029 2y ago
Another option is a variable speed condensing unit. This is what I am looking at doing next. A dedicated central dehumidifier is nice, but I've found them to be kind of noisy, especially when installed in the attic. Its got its own compressor, so the vibrations will transfer into the structure.
hunter2_ 2y ago
> Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Same, and the worst part is that Nest already includes a hygrometer to show humidity in the app. All they need to give the user is a toggle: setpoint in regular dry bulb temperature, or setpoint in calculated wet bulb temperature (or heat index or "feels like" or whatever user-friendly calculation). Although their remote temperature sensors don't have a hygrometer, only the main unit.
kjkjadksj 2y ago
Part of this is solved by sizing the ac correctly. Too powerful an ac and it doesn’t cycle as often and humidity builds.
wongarsu 2y ago

habitue 2y ago

Since this article uses that fluffy "tell a story" writing style, here's the facts in the article stripped out: 1. Air conditioning consumes 10% of global energy and 20% of energy used in buildings. 2. Demand for cooling is expected to increase significantly, with 2/3 of world households projected to have air conditioning by 2050. 3. Dehumidification accounts for over half of energy consumption in air conditioners in humid conditions. 4. New technologies are being developed to improve air conditioning efficiency: a. AirJoule by Montana Technologies: - Uses metal-organic framework material for dehumidification - Claims to reduce energy for dehumidification by up to 90% - Still in prototype and testing stages b. Blue Frontier: - Uses liquid desiccant for dehumidification - Being installed in various locations in the US c. IceBrick by Nostromo Energy: - Energy storage system for large-scale cooling - Can reduce annual cooling costs by 30% and associated emissions by up to 80% - Only suitable for centralized cooling systems d. Gradient: - Window-based heat pumps with larger external units for better efficiency - Currently costs $3,800, aiming to reduce to $1,000 5. Electrocaloric cooling is being researched as a potential future technology, potentially 20% more efficient than current methods. 6. Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run. 7. Current non-centralized air conditioners operate at only about 20% of their theoretical maximum efficiency.

klabb3 2y ago
> 6. Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run. What about insulation? In my experience the insulation in most hot places is abysmal, compared to cold places. I’m not even a layman, but shouldn’t the physics work the same? Or does the air flow from AC change the equation?
- cool_dude85 2y ago
  I live in Florida and new-build homes are relatively well-insulated. Older stuff can be anywhere from very poor to surprisingly good (e.g. old, small concrete block housing). And yes, the idea is broadly the same, although insulation doesn't help with de-humidification.

hgomersall 2y ago

In areas where water is not in particularly short supply, you can cool by evaporating water into the exhaust pre-heat-exchanger of an MVHR system. This then vents the warmer humid air into the outside and cools incoming air. The enthalpy diagram suggest it's quite helpful and there's a product on the market that uses exactly this approach. It's basically half of a closed cycle heat pump, in which the hot side is an externality.

HPsquared 2y ago
Could that increase the humidity in the surrounding street environment?
lsaferite 2y ago
Sounds similar to a swamp cooler.
- hgomersall 2y ago
  Indeed, but the difference is the high humidity cooled air is used to cool low humidity air, so you don't get the humidity increase inside.

0xbadcafebee 2y ago

We could reduce demand for air conditioning if we designed our lives around the natural environment rather than isolating ourselves from it. Right now we build giant boxes to live/move around in that suck up the sun's heat, then we insulate the box, then build another box to remove moisture in the box, cool the air in the box, blow it around, and then we have to power it... ....or we could live and move around in an open, shaded area, where wind can pass easily, fans blow on us to cool us (your skin is designed for cooling with wind, unlike most other animals on the planet), and cool mists can assist. The latter is how I stay comfortable while camping in 90% humidity and 90F temperature. There are other solutions too, like staying underground during the peak of the heat, taking a dip in a pool of water, drinking cold liquids. All these and more don't require an exponential increase in energy generation, advanced engineering, or boxes designed to create an artificial environment.

JumpCrisscross 2y ago

> The system wouldn’t suit a single house, as it only works with these large centralized cooling installations. However, it can be bolted to a variety of chiller plants—it doesn’t really matter what circulating fluid they use, for example, Ben Nun says We have district heating in New York [1]. Fascinating to think of district cooling, too. [1] https://en.wikipedia.org/wiki/District_heating https://en.wikipedia.org/wiki/District_heating

kasey_junk 2y ago
Chicago has district cooling https://wgntv.com/news/chicago-news/the-ice-machine-that-chills-chicagos-skyscrapers-inside-downtowns-district-cooling-systems/amp/ https://wgntv.com/news/chicago-news/the-ice-machine-that-chi...

ninininino 2y ago

Air conditioning should be applied only the to a bubble of cubic space surrounding the people in a given room as well as any temperature-sensitive goods like medicines, perishables, etc. We ought to develop tech to facilitate this, for example a mosquito net style insulating cocoon to enclose your bed at night that conditions the air inside of it but leaves the rest of the room warm.

kkfx 2y ago

Honestly it could be hardly used in practice. The frontier of cooling is: - living in MODERN, so air-tight, well insulated buildings, designed to get the Sun when needed in winter, but not get it in summer with simple design choices etc; -living in places where nights are fresh and having p.v. to cool with no energy consumption from grid during the day. Now the above points are a bit bold but try reasoning why we live where we live. In the past places where circadian thermal delta was/is lower was very good places because it was less hot than now and there was no cheap heating. Similarly living in some places very deep in a valley was nice because floods was a thing anyway, but having clean water was invaluable and homes back then have had much less things who can be damaged by floods. Climate have change but technology, human living is changed much more. In the present world many inhabited parts of the world that back than was nice places, today they are not and others back than not so nice today are nice places. In the past being many in a single places means: - being able to defend against enemies - having access to all professions and services - having trade and learning opportunities - be more exposed to illness, BUT being able to get help much easier now? It means that - 9/11 alike attacks or simple drone attacks are much more easy and deadly - you get more dysfunctional services because we are too dense for them in too many place (as an example packages delivery in large condo complex vs single family homes) - be more exposed to illness, with sometimes even LESS chances of a quick aid - being mostly limited by nearby activities instead of having plenty of space for build a new one and remote work Try to weight this, in terms of opportunities, disasters and who win vs who loose.