3 ms·

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 ene

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.
  - elric 2y ago
    A well insulated (air tight) house does make it easier to keep some humidity out with a ventilation system with an ERV (Energy/Enthalpy Recovering Ventilator). It basically has a membrane which keeps humidity on the most humid side. So it keeps indoor air dry in humid summers, and humid in dry winters. I have one, and it helps keep my house a lot more comfortable in summer, reducing the need for a/c to maybe a couple of weeks a year.
  - lsaferite 2y ago
    Having watched many homes being built here in FL, I don't hold the same opinion. Homes here are, in general, still poorly built. Even something as simple as 2x6 exterior framing (for more insulation depth) is not common. Don't even get me started on the lack of modern framing techniques or tight envelopes. Another one that drives me nuts is watching them leave attic unconditioned but they run HVAC vents through that same unconditioned space. All the insulation is in the ceiling, not the roof. It's really disappointing to watch TBH. No builders want the expense when they can build it poorly and the buyers don't really know better. If you build a custom home you can get better outcomes, but the prices jump drastically. Sorry, this is a sore subject for me apparently.
- danans 2y ago
  > What about insulation? > I’m not even a layman, but shouldn’t the physics work the same? Or does the air flow from AC change the equation? Insulation works great in hot climates, but only when the building is also well air-sealed and air-conditioned. Otherwise, insulation alone will just make a house work like an oven after it heats up (through radiant and convective heat gain).
elric 2y ago
> Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run. Technology Connections just did a video on awnings. I'm not quite as puppy eyed about them as TC, but they are pretty darn effective. https://www.youtube.com/watch?v=uhbDfi7Ee7k https://www.youtube.com/watch?v=uhbDfi7Ee7k
- bitmasher9 2y ago
  I hope someone takes the idea from this video and compiles it into more solid and actionable data. I would like something where I can describe my window location and the type of window and it tells me how much cooling I would gain with an awning.
  - drozycki 2y ago
    I believe this software is widely available to hvac contractors for accurately sizing a system. Haven’t seen it for mere mortals though
Flimm 2y ago
Thank you for the summary! (Note: indenting text with two spaces makes it render with a monospaced font on Hacker News, see https://news.ycombinator.com/formatdoc https://news.ycombinator.com/formatdoc )
gilleain 2y ago
> Uses metal-organic framework material for dehumidification MOFs are super interesting! https://en.wikipedia.org/wiki/Metal%E2%80%93organic_framework https://en.wikipedia.org/wiki/Metal%E2%80%93organic_framewor... they are one of the most complex non-biological structures I know of

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.
- elric 2y ago
  A well insulated (air tight) house does make it easier to keep some humidity out with a ventilation system with an ERV (Energy/Enthalpy Recovering Ventilator). It basically has a membrane which keeps humidity on the most humid side. So it keeps indoor air dry in humid summers, and humid in dry winters. I have one, and it helps keep my house a lot more comfortable in summer, reducing the need for a/c to maybe a couple of weeks a year.
- lsaferite 2y ago
  Having watched many homes being built here in FL, I don't hold the same opinion. Homes here are, in general, still poorly built. Even something as simple as 2x6 exterior framing (for more insulation depth) is not common. Don't even get me started on the lack of modern framing techniques or tight envelopes. Another one that drives me nuts is watching them leave attic unconditioned but they run HVAC vents through that same unconditioned space. All the insulation is in the ceiling, not the roof. It's really disappointing to watch TBH. No builders want the expense when they can build it poorly and the buyers don't really know better. If you build a custom home you can get better outcomes, but the prices jump drastically. Sorry, this is a sore subject for me apparently.
danans 2y ago
> What about insulation? > I’m not even a layman, but shouldn’t the physics work the same? Or does the air flow from AC change the equation? Insulation works great in hot climates, but only when the building is also well air-sealed and air-conditioned. Otherwise, insulation alone will just make a house work like an oven after it heats up (through radiant and convective heat gain).

elric 2y ago

> Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run. Technology Connections just did a video on awnings. I'm not quite as puppy eyed about them as TC, but they are pretty darn effective. https://www.youtube.com/watch?v=uhbDfi7Ee7k https://www.youtube.com/watch?v=uhbDfi7Ee7k

bitmasher9 2y ago
I hope someone takes the idea from this video and compiles it into more solid and actionable data. I would like something where I can describe my window location and the type of window and it tells me how much cooling I would gain with an awning.
- drozycki 2y ago
  I believe this software is widely available to hvac contractors for accurately sizing a system. Haven’t seen it for mere mortals though

Flimm 2y ago

Thank you for the summary! (Note: indenting text with two spaces makes it render with a monospaced font on Hacker News, see https://news.ycombinator.com/formatdoc https://news.ycombinator.com/formatdoc )

gilleain 2y ago

> Uses metal-organic framework material for dehumidification MOFs are super interesting! https://en.wikipedia.org/wiki/Metal%E2%80%93organic_framework https://en.wikipedia.org/wiki/Metal%E2%80%93organic_framewor... they are one of the most complex non-biological structures I know of