TIL Ancient Persians built Yakhchāls, innovative ice storage structures dating back to 400 BC. These dome-shaped coolers used evaporative cooling to keep ice frozen even during hot summers.

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What's stopping us from using similar techniques in hot climates now? Why aren't we building similar structures as homes in Phoenix instead of the standard suburban homes?

Probably because you still need a lot of water for this to work.

Or a clever contraption with something with a lower evaporation point and a closed loop that catches the evaporated fumes for reuse. Maybe add the ability to speed up the process with a little electricity and you've got modern AC.

I am not an engineer, but PV-panels (or wind turbine or any other power generation system) and an AC might achieve a better result using less space?

You can. You can get evaporative coolers (in the US, sometimes called swamp coolers). I have one. They use much less power per unit of cooling than air conditioners, but come with some drawbacks:

  • You can only cool so far (well, you can build multi-stage systems to cool further, but then power efficiency drops off). Air conditioners don't have such a limitation --- throw more power at them, and they'll make air colder.

  • You must have low humidity, so that the water can evaporate. At 100% relative humidity, they're totally inoperative. Air conditioners don't have this requirement.

  • If using them indoors, you have to ventilate to the outside, usually by keeping some windows open, or you'll just drive humidity up to the max and then they'll stop functioning. This does have the benefit of keeping air fresh, having a high turnover, but caps how cool they can make a structure. Air conditioners don't require this.

  • More maintenance. You occasionally need to replace the membrane and put something in the water to kill algae, same as a swimming pool. Don't do that, and algae will build up and it'll get a dank smell. Air conditioners just require cleaning or replacing an air filter occasionally, and if you don't do that, just become less efficient.

  • An evaporative cooler requires a water feed and for forced air, power. Air conditioners only require power.

  • They will exacerbate any humidity problems, like mold.

There are also some benefits:

  • For direct systems (the simplest and cheapest), where the humidified air blows at you, you get the benefits of a humidifier, like not getting chapped lips or becoming dehydrated easily. In arid and semi-arid environments where evaporative coolers work well, this is pleasant.

  • You can reasonably use them outdoors and in non-sealed environments like a garage. Air conditioners would be really inefficient for this.

  • You can easily throw essential oils in the water to get a scent diffuser.

  • They actually cool the air, rather than just dumping the heat somewhere else, as air conditioners do (which in cities, heats up the area around buildings).

I understand that there are also some hybrid "evaporative-assisted" air conditioners that have the air conditioner dumping heat into what amounts to an evaporative cooler. That'd get some of the efficiency benefits of an evaporative cooler without the humidity constraints.

You can find them in the hot, arid American West, where the conditions work well for them.

https://www.usgs.gov/media/images/evaporative-coolers-work-best-dry-areas-us-area-a

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Yeah, Crusader Kings III taught me those existed, and not too long ago, it had me dive into a Wikipedia rabbit hole. They also used shade walls and radiative cooling to create ice during cold desert nights, which then remained long enough to be harvested in the morning and put into well-constructed ice houses like this. Also, wind catchers and Qanats.

This was a quest in Breath of the Wild

A game is forcing me to cross-dress to gain access to an all-female area, inhabited by tall beautiful mommies? "Ohnooo"

It was the Gerudo icehouse quest! It's amazing to me how close to history I am sort of. When my grandma was little, they didn't have fridges, and they used to pile snow and ice and compact it and then cover it with sawdust, behind the sauna where the sun wouldn't be shining. She said it usually lasted till around June. Perhaps even later can't remember and can't ask anymore. RIP.

Arizona seniors would like this.

This was an area in Wizard101

Stuff You Should Know covered this

frequently including sand, clay, egg white, goat's hair, lemon juice, ash, and a technical water-

The fuck is goat's hair? Isn't it called fur? Unless it's specifically fur on their head?

I think it's rather to distinguish between fur as being understood from skinning the animal and using the resulting hide including the hair versus cutting the hair from the skin and receiving the single hair strands and using those strands in construction.

But just how I imagined it is meant, no idea if that is true.

Seems like loose goat hair with clay could be used similarly to fiberglass with resin, or steel reinforcements in cement, just a different use case.

Horse hair is very much a thing and used for insulation. I lived in an apartment in Boston built in the 1890s that had horse-hair insulation.

I do think it's from the mane and tail and not the fine fur of the body. But that would just be an assumption.

No I don't think so. For instance we say cat hair but they have fur. I think it's just a weird English thing.

Usually hair is long and typically sparse on animals like us, fur is short and covers the whole body like a moose.

Wow! Just look at them now! 😅

Hey, will you explain this to me? I don't get it.

Essentially, they went on to become Iran. 🤢

I know, I just wanted you to be more obvious about the gross thing you said.

They could've been so much more, but "government" & religion fucked them. A tale as old as time.

And?

🤦🏼‍♂️

Your very judgy for someone who has done nothing to make their own country great. Your only tie to greatness is that you were accidentally squeezed out of your mom's junk in a convenient country.

If you were born in Iran, you wouldn't have done any better than they did.

Project much? 🤣🖕🏼 For all you know, I could've done positively impactful things for decades before you ever squirted onto this tiny blue speck of a planet. You do you, keyboard ninja. 😚

And you went on to become Iblock.

Aw, is that other place still dribbling out its residue? Poor thing