The Ancient Persian way to keep cool(bbc.com)
bbc.com
The Ancient Persian way to keep cool
https://www.bbc.com/future/article/20210810-the-ancient-persian-way-to-keep-cool
193 comments
Would stone slabs for housing scale for tens of millions living in this desert?
Maybe it would, but I have to imagine the mass of resources required would go up. Concrete with insulation is cheaper and less massive to build.
Mud and fiber or wattle have good properties too. Would we have enough resources for building housing for tens of millions out of these materials?
As one offs we can find a multitude of good solutions. The problem is finding affordable mass produced options for all the people who can’t afford iteresting bespoke solutions.
Maybe it would, but I have to imagine the mass of resources required would go up. Concrete with insulation is cheaper and less massive to build.
Mud and fiber or wattle have good properties too. Would we have enough resources for building housing for tens of millions out of these materials?
As one offs we can find a multitude of good solutions. The problem is finding affordable mass produced options for all the people who can’t afford iteresting bespoke solutions.
> As one offs we can find a multitude of good solutions. The problem is finding affordable mass produced options for all the people who can’t afford iteresting bespoke solutions.
Exactly, because the resources actually exist but nobody can profit off it. Our economic system repeatedly drives us away from sane and coherent solutions to our problems. Maybe we should look at changing that.
Exactly, because the resources actually exist but nobody can profit off it. Our economic system repeatedly drives us away from sane and coherent solutions to our problems. Maybe we should look at changing that.
I hear that argument a lot in the context of drugs -- you can't patent a natural remedy so there's no big corporation pushing for it's adoption. But concrete is not like that. The reason it's so widely used is precisely because it's easy to use widely. I mean, 2m thick stone walls are surely great if space and energy constraints allow you to put them up ...
Let those who want 2m stone pay for it, and let all others suffer in ignorance
> think they can build way out into the desert
…but they can, all it takes is the lifeblood of civilization: energy. It need not even be oil-driven, though of course in their case it is.
…but they can, all it takes is the lifeblood of civilization: energy. It need not even be oil-driven, though of course in their case it is.
This strikes me as a case particularly well-suited/well-matched for solar.
Exactly, when the sun is hottest, the AC is blasting. The only catch is that you might need to heat at night even in summer in some parts.
You would think there would be traditional solutions for that, why not a put a cart full of dark stones in the sun during the day and then roll it inside in the cold of night? Modern variations on that theme could store thermal energy in plenty of equally-simple ways.
There are all sorts of things that are technically possible but the materials handling requirements do not make them cheap/efficient enough to do practically without electricity. See aluminum ore processing for example.
A house may be "a machine for living in" but the scale of the solutions needed aren't as serious as industrial processes like mining surely? I haven't lived in a structure using them, but there are Phase Change[1] insulations out there, for example.
1: https://en.wikipedia.org/wiki/Phase-change_material
1: https://en.wikipedia.org/wiki/Phase-change_material
You want to maximize how much the house cools at night to minimize daytime temperature. Then to maintain a comfortable temperature just add thermal mass.
Probably less work to just have a lot of blankets!
In the Middle East, during summer, you don't need heating at night; it's still easily north of 30C
Let's rephrase that to needing energy at night - heating or cooling. There are some spots that go down to 10C in summer according to Google
Solar panel efficiency goes down in high temperatures, so it wouldn't be great in really hot places.
[deleted]
If they're so great, why don't they make an appearance in the Dune series? More seriously, Frank Herbert did his research, but these do not appear (AFAIK).
So, wait, you're seriously advocating 2 meter thick walls (yeah, I know, let's say starting at 1/2 meter) as a solution for a dense city? Price at build time is hardly the only problem.
Good luck with that.
Good luck with that.
That’s not the point of vernacular architecture. Read or skim the wiki. The beauty of it is adapting to the surroundings to maximize environmental benefits as a way of preventing environmental externalities or other damages — at least in the sense of climate.
So to respond to your glib remark, no I’m not seriously proposing 2m walls for everyone. That’s ridiculous. There are better ways of building. (We actually have the technology to make net positive energy buildings with sophisticated materials and capture techniques.) The point of my comment was to show the ignorance of modern building techniques in a desert that was doing just fine until modernity started mixing in concrete. Vernacular architecture doesn’t have to be applied everywhere, but we can learn from it and implement what’s convenient.
On a parting note, I like to think of my old building’s thick stone walls built from rock probably quarried at the time on the other side of the hill. We have a southern exposure, and yet the rooms remain chilled without air conditioning so long as I shut the metal blinds at peak heat, and we are warm enough in the winters that we don’t need space heaters everywhere. The same can’t be said for my friend across the city in a newer apartment building that likely isn’t made with hefty stone.
So to respond to your glib remark, no I’m not seriously proposing 2m walls for everyone. That’s ridiculous. There are better ways of building. (We actually have the technology to make net positive energy buildings with sophisticated materials and capture techniques.) The point of my comment was to show the ignorance of modern building techniques in a desert that was doing just fine until modernity started mixing in concrete. Vernacular architecture doesn’t have to be applied everywhere, but we can learn from it and implement what’s convenient.
On a parting note, I like to think of my old building’s thick stone walls built from rock probably quarried at the time on the other side of the hill. We have a southern exposure, and yet the rooms remain chilled without air conditioning so long as I shut the metal blinds at peak heat, and we are warm enough in the winters that we don’t need space heaters everywhere. The same can’t be said for my friend across the city in a newer apartment building that likely isn’t made with hefty stone.
Could you make your comment more helpful?
At the moment it can be summarized as "more concrete is more expensive". It's seems you have more thoughts on it, but it's hard to infer much else from it.
At the moment it can be summarized as "more concrete is more expensive". It's seems you have more thoughts on it, but it's hard to infer much else from it.
My reading was that the issue is the massively increased footprint of every building, not the cost of the concrete.
He mentions density, which to me all most always comes down to height. How tall of a building can you build with meter thick walls?
The monadnock building in Chicago [0] partially answers your question:
“ The Monadnock's final height was calculated to be the highest economically viable for a load-bearing wall design, requiring walls 6 feet (1.8 m) thick at the bottom and 18 inches (46 cm) thick at the top. Greater height would have required walls of such thickness that they would have reduced the rentable space too greatly.”
[0] https://en.m.wikipedia.org/wiki/Monadnock_Building
“ The Monadnock's final height was calculated to be the highest economically viable for a load-bearing wall design, requiring walls 6 feet (1.8 m) thick at the bottom and 18 inches (46 cm) thick at the top. Greater height would have required walls of such thickness that they would have reduced the rentable space too greatly.”
[0] https://en.m.wikipedia.org/wiki/Monadnock_Building
These days we can achieve insulation with better materials without sacrificing real estate.
It's not just about insulation. It's also about thermal mass, a.k.a. thermal capacitance a.k.a. heat capacity - how much heat to the falls retain.
In a desert, buildings with thick stone or earthen walls will get cool at night thanks to the cool desert night air. They will stay cool throughout the day and the building's interior will remain cool(er) as a result even in the afternoon. (Conversely, the buildings will remain warm at night for the same reason)
Of course, this is most effective in an environment like a desert where you have a large diurnal temperature swing: scorching days and chilly nights.
But many/all of the same principles can be employed in temperate climates in a modified form, such as with earth-sheltered homes https://en.wikipedia.org/wiki/Earth_shelter
In a desert, buildings with thick stone or earthen walls will get cool at night thanks to the cool desert night air. They will stay cool throughout the day and the building's interior will remain cool(er) as a result even in the afternoon. (Conversely, the buildings will remain warm at night for the same reason)
Of course, this is most effective in an environment like a desert where you have a large diurnal temperature swing: scorching days and chilly nights.
But many/all of the same principles can be employed in temperate climates in a modified form, such as with earth-sheltered homes https://en.wikipedia.org/wiki/Earth_shelter
In temperate climates mold is a bigger problem than cooling. Especially when building underground.
Air conditioning mitigates mold by removing moisture from the air…which doesn’t mean that ac ducts won’t hold mold if there’s improper operation or bad design.
Earth homes are uncommon because building science is empirical not theoretical. Because the construction market is efficient even though its efficiency doesn’t mean you can afford a house in a desirable location.
Air conditioning mitigates mold by removing moisture from the air…which doesn’t mean that ac ducts won’t hold mold if there’s improper operation or bad design.
Earth homes are uncommon because building science is empirical not theoretical. Because the construction market is efficient even though its efficiency doesn’t mean you can afford a house in a desirable location.
Mold is problem for modern construction techniques. Mold is ubiqutous in the UK, but wasn't a problem for buildings themselves until the advent of contemporary (English) construction techniques. Those hundreds-of-year-old homes built of stone don't have issues with mold (their inhabitants might). It doesn't take much more than ensuring proper airflow to mitigate mold issues in actually temperate climates.
Now, mold in, say, the SE USA (or even the mid-Atlantic region), is a different story, but once again, well built homes there from the 1800s can and have avoided mold issues with good air flow design.
Now, mold in, say, the SE USA (or even the mid-Atlantic region), is a different story, but once again, well built homes there from the 1800s can and have avoided mold issues with good air flow design.
Assuming you can afford to source those better materials. It’s a trade off, thermal quality of materials vs cost/access. We’re heading in a direction where most people will not be able to afford the best insulation and so learning from the past becomes essential.
That's only a problem if you're building with expensive materials. Build those walls with earth and aggregate and the biggest expense is gas for the heavy equipment.
It also takes considerably more space, which is the most expensive common/necessary building material anyway.
Only the outer walls would be 2 meters thick, right? So we're talking about adding less than 4 meters to the diameter of every building, which... I don't know, that doesn't seem like a ton of extra space being consumed.
Wall area is O(n^2) not O(n).
A 50x50 building with 8” CMU walls (0.2 meter) enclosed 2460m^2 floor area.
With 2m walls only 2100m^2.
A more dwelling sized building of say 25x10m is 246.5 versus 110m.
Until I designed tract housing to with floor area targets, it was not obvious how much difference a few inches here and there made. But that’s literally how an initial design that works out around 1900sf is made to fit into the 1700sf gap in the product line…it’s not like you can lop off the kitchen.
A 50x50 building with 8” CMU walls (0.2 meter) enclosed 2460m^2 floor area.
With 2m walls only 2100m^2.
A more dwelling sized building of say 25x10m is 246.5 versus 110m.
Until I designed tract housing to with floor area targets, it was not obvious how much difference a few inches here and there made. But that’s literally how an initial design that works out around 1900sf is made to fit into the 1700sf gap in the product line…it’s not like you can lop off the kitchen.
I was very confused by this at first! Clearly you know what you're talking about, so I struggled a minute to walk through the math.
My super-naive approach is to say: infinitely thin walls would mean 50x50=2500m^2, but having 0.2m walls would make it really 49.6x49.6=2460.16m^2, so basically what you said. 2m walls would make it 46x46=2116m^2, so again, pretty much what you said.
So I don't disagree on the math, but I guess I'm not sure about how much of an issue that is, especially when other factors are considered, such as:
Generally either a building has a little space to expand outward in a given direction or it's smack against another building in which case that seems like more of an interior wall, not needing to be 2m thick. Right? Maybe that's where I'm lost. Like, you're talking about a 10m wide building, but I'm thinking that a 10m wide building probably already abuts a building on each side, so no airflow there, so no need for 2m walls. Whichever sides do not abut another building, and therefore might get airflow, would need a 2m wall, but it seems likely that could happen by expanding the footprint more easily than by shrinking the interior.
I'm sure there are exceptions, but am I way off-base? I might be.
My super-naive approach is to say: infinitely thin walls would mean 50x50=2500m^2, but having 0.2m walls would make it really 49.6x49.6=2460.16m^2, so basically what you said. 2m walls would make it 46x46=2116m^2, so again, pretty much what you said.
So I don't disagree on the math, but I guess I'm not sure about how much of an issue that is, especially when other factors are considered, such as:
Generally either a building has a little space to expand outward in a given direction or it's smack against another building in which case that seems like more of an interior wall, not needing to be 2m thick. Right? Maybe that's where I'm lost. Like, you're talking about a 10m wide building, but I'm thinking that a 10m wide building probably already abuts a building on each side, so no airflow there, so no need for 2m walls. Whichever sides do not abut another building, and therefore might get airflow, would need a 2m wall, but it seems likely that could happen by expanding the footprint more easily than by shrinking the interior.
I'm sure there are exceptions, but am I way off-base? I might be.
The value of a building has a strong correlation to its net area. 300 square meters is a lot of area…more than a $100,000/year at $35/square foot. Over $1,000,000 at ten years. Over $3,000,000 over the life of a thirty year mortgage.
And that’s per floor.
And that’s per floor.
Land is an expensive material.
So's labor, and building anything slightly odd adds even more to costs, for a bunch of reasons. Just building a standard house with somewhat upgraded R-value insulation, solar panels, and a "geothermal" heat-pump, would be a hell of a lot cheaper. Plus you'd actually be able to sell it in a normal time-frame and for a normal price, if you decide to move.
R-value doesn't really address thermal mass issues. I live near Santa Fe, NM and given our daily temperature swings (up to 40F!) and annual variation (100F to 5F), comfortable housing here benefits from both insulation and thermal mass. Geothermal heat pumps seem less practical than air-source right now, and a 6.6kW array turns out not to be enough even with Mitsubishi units to keep out (adobe) home warm in the winter.
Stud-based construction is quick and relatively quick, and might even be appropriate in the right climate. But in places like this (and many others), it's a mistake that you can ameliorate (e.g. with insulation) but cannot actually fix.
Stud-based construction is quick and relatively quick, and might even be appropriate in the right climate. But in places like this (and many others), it's a mistake that you can ameliorate (e.g. with insulation) but cannot actually fix.
> network of couriers called pirradaziš that predate postal services in the US by more than 2,000 years.
Hilarious! Why would you make that comparison?
It's as if someone wrote "Ötzi had remains of a meal in his gut that predates my breakfast by more than 5000 years."
Hilarious! Why would you make that comparison?
It's as if someone wrote "Ötzi had remains of a meal in his gut that predates my breakfast by more than 5000 years."
> Why would you make that comparison?
"Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds"
Because the informal creed of USPS is that of the postal service of the first Persian Empire.
"It is said that as many days as there are in the whole journey, so many are the men and horses that stand along the road, each horse and man at the interval of a day’s journey; and these are stayed neither by snow nor rain nor heat nor darkness from accomplishing their appointed course with all speed." — Herodotus, Histories (8.98) (trans. A. D. Godley, 1924)
https://en.wikipedia.org/wiki/United_States_Postal_Service_c...
"Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds"
Because the informal creed of USPS is that of the postal service of the first Persian Empire.
"It is said that as many days as there are in the whole journey, so many are the men and horses that stand along the road, each horse and man at the interval of a day’s journey; and these are stayed neither by snow nor rain nor heat nor darkness from accomplishing their appointed course with all speed." — Herodotus, Histories (8.98) (trans. A. D. Godley, 1924)
https://en.wikipedia.org/wiki/United_States_Postal_Service_c...
I saw that and I was like “everything they did was 2000 years before it right?”
The author is hyping it up too much. The author goes on to speculate that people are going to give up air conditioning for this.
The author is hyping it up too much. The author goes on to speculate that people are going to give up air conditioning for this.
Systems like this wouldn't replace air conditioning in all settings but they might influence the design and integration of future air conditioning systems. I can easily imagine architecture that incorporates air catchers which feed a cool breeze into electronic temperature precision units that are significantly more energy efficient. We can combine this with what we know about fluid dynamics and creating air pressure differentials to move cool air through structures at near zero cost.
AC units with massive fans doing all the heavy lifting are incredibly inefficient.
AC units with massive fans doing all the heavy lifting are incredibly inefficient.
> AC units with massive fans doing all the heavy lifting are incredibly inefficient.
By what criteria? How much energy does it take to move the air around compared to actually cooling it?
By what criteria? How much energy does it take to move the air around compared to actually cooling it?
[deleted]
Perspective and fun.
> As a wind catcher requires no electricity to power it
Another fun gem putting things into perespective. Placed in the middle of article where it was already firmly estabilished that those windcatchers were built in ancient times.
Another fun gem putting things into perespective. Placed in the middle of article where it was already firmly estabilished that those windcatchers were built in ancient times.
Things that are obvious to you and I might not be obvious to every reader. Remember that the BBC has a broad demographic, including kids and people of varying educational backgrounds. Their content is intentionally written to be accessible rather than placing assumptions on the readers prior knowledge.
Do you think that many readers patient and interested enough to reach this point in the article lack knowledge that there was no electricity in the ancient times?
Many? No.
Some? Given the laws of probability and the points I raised in my previous post, yes it is possible.
If you take issue with BBC's mission (https://www.bbc.com/aboutthebbc/governance/mission) then I suggest you research the same content from different sources rather than moaning about it on HN because for a great deal of people in the world (and especially in the UK) the BBC is a great source of accessible content. And frankly, it's much easier to criticise someone else's writing than it is to publish something that is both informative and accessible.
Some? Given the laws of probability and the points I raised in my previous post, yes it is possible.
If you take issue with BBC's mission (https://www.bbc.com/aboutthebbc/governance/mission) then I suggest you research the same content from different sources rather than moaning about it on HN because for a great deal of people in the world (and especially in the UK) the BBC is a great source of accessible content. And frankly, it's much easier to criticise someone else's writing than it is to publish something that is both informative and accessible.
I am not hating on BBC just this specific article of this specific author.
I've seen people honestly believe than the world was black and white right to the middle of 20 century. You're way too optimistic.
I don't think those people read those kinds of articles. Or read anything beyond TV guide.
Cinematic tropes of ancient times often show thing slike slaves operating giant fans, either hand held or operated by levels. Since slavery is no longer acceptable it's not surprising that people might be defaulting to the assumption that cooling requires mechanical movement which requires energy, whereas this form of cooling is wholly passive in nature.
The baghdad battery is ~2000 years old, so it might be important to point this out.
It's strongly disputed that this device was built to produce electricity.
Gotta hit those SEO text length targets with as little effort as possible.
It's a still-active city, not an archeological site where everything has been in stasis. Why would you assume everything there is 2,000 years old?
Other cool ancient tech in Persia are the ice houses https://en.m.wikipedia.org/wiki/Yakhch%C4%81l and the underground canals
https://en.m.wikipedia.org/wiki/Qanat that can be thousands of meters long.
Qanats are a fascinating engineering feat requiring a precise slope of 1:1000 or less, built over 2000 years ago. It is really amazing what these ancient civilisations built with the technology available.
ETA: Also one of the few scrabble words with a "q" but no "u" :-)
ETA: Also one of the few scrabble words with a "q" but no "u" :-)
> that can be thousands of kilometers long
"Most qanats in Iran run less than 5 km (3.1 mi), while some have been measured at ≈70 km (43 mi) in length near Kerman" --https://en.m.wikipedia.org/wiki/Qanat
"Most qanats in Iran run less than 5 km (3.1 mi), while some have been measured at ≈70 km (43 mi) in length near Kerman" --https://en.m.wikipedia.org/wiki/Qanat
Sorry, fixed that!
I'm from that region with lots of Qanats and I remember we used to fish in them. Thinking back, I now realise how awesome it was to do that. Always curious how the fish ended up there.
Probably thrown and then multiplied by itself, with plenty of insects to eat
Last couple of summers we've had extended periods where my flat can reach a pretty uncomfortable temperature to work in. I do not want to install AC and have so far managed to counteract it by making sure my windows are open overnight to circulate cool air and by closing different curtains + blinds through the day (one half of my flat gets morning sun, the other half evening sun). This keeps the air in the flat comfortably below the outside temperature, but if I forget to do either of these steps the temperature can creep up a bit and it's not possible to cool it down until evening (and if it's super humid and hot it might not cool that much).
I'm wondering if there's any low-energy or green solutions to this. I suspect I'm asking for something impossible or that the only way to improve this is to automate the blind opening/closing :-/
I'm wondering if there's any low-energy or green solutions to this. I suspect I'm asking for something impossible or that the only way to improve this is to automate the blind opening/closing :-/
If you live in a cold climate, buy a mini-split (a type of AC that also works in reverse).
ACs are very efficient (more than 100%!). By using an AC to heat (a Delta(T) in my city of at least 30C) your home in the winter you more than offset the carbon to cool and dehumidify it a mere 5-10C (again, in my case).
Heating a home in cold climates are far worse than cooling, but there's a puritan rejection of AC:.
- The Delta(T) is larger to heat a home than to cool it. Delta(T) sets the heat loss through your walls.
- There is an attitude that cooling is hedonistic, while heating is a necessity, but it's thermodynamically and metabolically far easier to heat than to cool.
- Most heating is done with fossil fuel furnaces which are at best 90-95% efficient. A heat pump can be over 300% efficient [1] (i.e. it moves 3J of heat from the cold side to the hot side using only 1J). This is much better improvement in performance than an electrical car.
Get an AC that can work in reverse, and if you want don't use it in the summer.
EDIT (added following):
[1] The metric here is coefficient of performance, COP = Thigh / (Thigh - Tlow). For 30C to 20C the theoretical maximum is 3 000%, or 30x
[2] No, you can't break thermo laws with [1].
ACs are very efficient (more than 100%!). By using an AC to heat (a Delta(T) in my city of at least 30C) your home in the winter you more than offset the carbon to cool and dehumidify it a mere 5-10C (again, in my case).
Heating a home in cold climates are far worse than cooling, but there's a puritan rejection of AC:.
- The Delta(T) is larger to heat a home than to cool it. Delta(T) sets the heat loss through your walls.
- There is an attitude that cooling is hedonistic, while heating is a necessity, but it's thermodynamically and metabolically far easier to heat than to cool.
- Most heating is done with fossil fuel furnaces which are at best 90-95% efficient. A heat pump can be over 300% efficient [1] (i.e. it moves 3J of heat from the cold side to the hot side using only 1J). This is much better improvement in performance than an electrical car.
Get an AC that can work in reverse, and if you want don't use it in the summer.
EDIT (added following):
[1] The metric here is coefficient of performance, COP = Thigh / (Thigh - Tlow). For 30C to 20C the theoretical maximum is 3 000%, or 30x
[2] No, you can't break thermo laws with [1].
Wow ok by an interesting coincidence I’m actually needing to upgrade my heating too (everyone moved off the building’s shared boiler, then voted to get rid of it at the one meeting I missed - hats off to them). Installing a new gas boiler and fitting it to the existing system means ripping up some of my (beautiful old and recently refurbished parquet) flooring so if this gives me a way to avoid that AND maybe cool the air relatively efficiently during the worst summer days I’ll definitely need to look into it!
Study it a bit while it's still warm and look up your local weather. [1]
The COP gets worse as Delta(T) increases and heat pumps are nowhere near the theoretical best, so at a certain point it's better to use gas. But that's typically below 0F (-10C).
I put in a four way Mitsubishi (2x as expensive but super silent) in my old home. Relatively happy with it, except I don't think the installers put enough coolant in it (it's best to instal a heat pump on a cool day). The air does gets a bit dry, so consider getting a heating humidifier for the night.
Finally, if you can afford it and if you can install it, a heat-pump with buried coolant lines really multiplies the efficiency (since the ground is above freezing and acts as a heat store through the seasons)
EDIT:
[1] If you live near a large body of water, especially if it's salty, it's very unlikely your cold days are cold enough to be a problem for the AC. Unless you live in Thunder Bay.
[2] AC is not a huge climate problem. Heating, cars, global supply chains, agriculture are bigger problems. AC just gets the attention because it's considered frivolous. A bigger problem is that modern homes are built with no consideration for cooling. My old house was 100 years old and naturally kept cool. My new house has at least 7 seven!!! skylights. It's impossible to cool. At least 5 of them face north :S
The COP gets worse as Delta(T) increases and heat pumps are nowhere near the theoretical best, so at a certain point it's better to use gas. But that's typically below 0F (-10C).
I put in a four way Mitsubishi (2x as expensive but super silent) in my old home. Relatively happy with it, except I don't think the installers put enough coolant in it (it's best to instal a heat pump on a cool day). The air does gets a bit dry, so consider getting a heating humidifier for the night.
Finally, if you can afford it and if you can install it, a heat-pump with buried coolant lines really multiplies the efficiency (since the ground is above freezing and acts as a heat store through the seasons)
EDIT:
[1] If you live near a large body of water, especially if it's salty, it's very unlikely your cold days are cold enough to be a problem for the AC. Unless you live in Thunder Bay.
[2] AC is not a huge climate problem. Heating, cars, global supply chains, agriculture are bigger problems. AC just gets the attention because it's considered frivolous. A bigger problem is that modern homes are built with no consideration for cooling. My old house was 100 years old and naturally kept cool. My new house has at least 7 seven!!! skylights. It's impossible to cool. At least 5 of them face north :S
Yeah i'm in central europe which is somewhat approaching continental climate - so bitter winters and toasty summers (not quite as bad as some parts of Ukraine and Russia ofc). But I'll def read into it, I'm glad I at least have another option even if it might not work out. Thanks!
In Massachusetts, homes with mini splits always have another heat source for when it gets cold enough that the efficiency drops. It’s more like 20F even though technically the devices can work down to 0F. If you want to go green you can try electric baseboards and just hope you rarely use them.
On your second bullet point, did you mean to say
"but it's thermodynamically and metabolically far easier to cool than to heat"
Because that seems to be more in line with the point you are making. Sorry to be a pedant, I'm asking because your comment is very interesting.
"but it's thermodynamically and metabolically far easier to cool than to heat"
Because that seems to be more in line with the point you are making. Sorry to be a pedant, I'm asking because your comment is very interesting.
No need to apologize, precision is important. Perhaps my point blurred two different things.
Point number 1 (directly referencing your question):
No, I did mean it's easier to heat than to cool. Basically every mechanism release heat, including heat pumps. Ultimately, to get a person to a comfortable temperature, all that is needed is to wrap them up in insulation until their body heat matches the heat loss for the required Delta(T).
Cooling is another thing altogether. There is no cooling mechanism, all we can do is:
1. absorb heat (i.e. evaporation) 2. move it somewhere else (i.e. heat pumps)
Your body can do 1. but only if the humidity is low enough, but it can't do 2. My conclusion here is to illustrate that your body can largely take care of itself when it comes to warming itself up, but it's (comparatively) very bad at cooling itself.
Point number 2:
While heating is very easy, it's also very energetically wasteful for two reasons:
1. The Delta(T) you have to fight against is larger, often double so the losses are larger (Delta(T) sets the heat loss of your home)
2. Most heating isn't done with heat pumps which are very efficient, whereas all cooling is pretty much only done with heat pumps [1].
3. You can use heat that the AC moved around. Today you can hook up your AC to your boiler so the heat you moved out of your home is dumped into your boiler. As long as you use enough hot water, the more you run your AC the lower your carbon emissions will be since the water boiler runs off gas (I'm not advocating for using more hot water, btw)
So, while using your AC is not good for the climate, it is not the easiest optimization to do first.
[1] Swamp coolers are weird: you live in an arid enough place that evaporating water cools you down... so you waste that precious water when you could just run an AC???
Point number 1 (directly referencing your question):
No, I did mean it's easier to heat than to cool. Basically every mechanism release heat, including heat pumps. Ultimately, to get a person to a comfortable temperature, all that is needed is to wrap them up in insulation until their body heat matches the heat loss for the required Delta(T).
Cooling is another thing altogether. There is no cooling mechanism, all we can do is:
1. absorb heat (i.e. evaporation) 2. move it somewhere else (i.e. heat pumps)
Your body can do 1. but only if the humidity is low enough, but it can't do 2. My conclusion here is to illustrate that your body can largely take care of itself when it comes to warming itself up, but it's (comparatively) very bad at cooling itself.
Point number 2:
While heating is very easy, it's also very energetically wasteful for two reasons:
1. The Delta(T) you have to fight against is larger, often double so the losses are larger (Delta(T) sets the heat loss of your home)
2. Most heating isn't done with heat pumps which are very efficient, whereas all cooling is pretty much only done with heat pumps [1].
3. You can use heat that the AC moved around. Today you can hook up your AC to your boiler so the heat you moved out of your home is dumped into your boiler. As long as you use enough hot water, the more you run your AC the lower your carbon emissions will be since the water boiler runs off gas (I'm not advocating for using more hot water, btw)
So, while using your AC is not good for the climate, it is not the easiest optimization to do first.
[1] Swamp coolers are weird: you live in an arid enough place that evaporating water cools you down... so you waste that precious water when you could just run an AC???
It is in fact thermodynamically and metabolically far easier to heat than to cool.
We're warm-blooded creatures, so if we want to be warmer we can just jump around, or put on insulation. To cool, we have to sweat, and if the sweat can't evaporate much because of high humidity, we have to do a lot of it.
Similarly, if we want to heat a space, we can just burn something. Cooling requires active transport, whether finessed by something like a windcatcher or attic fan, or through an air conditioner.
Heat pumps are more efficient, but more complex, than furnaces, and can be run in reverse to provide air conditioning.
We're warm-blooded creatures, so if we want to be warmer we can just jump around, or put on insulation. To cool, we have to sweat, and if the sweat can't evaporate much because of high humidity, we have to do a lot of it.
Similarly, if we want to heat a space, we can just burn something. Cooling requires active transport, whether finessed by something like a windcatcher or attic fan, or through an air conditioner.
Heat pumps are more efficient, but more complex, than furnaces, and can be run in reverse to provide air conditioning.
People really don't appreciate how brutal humidity is on our bodies' ability to cool down.
I run my AC more to dehumidify than to cool. I hate setting my AC below 78, that's freezing, but I have to because of improperly sized AC units, poor HVAC installation, etc.
I run my AC more to dehumidify than to cool. I hate setting my AC below 78, that's freezing, but I have to because of improperly sized AC units, poor HVAC installation, etc.
> I hate setting my AC below 78, that's freezing, but I have to because of improperly sized AC units, poor HVAC installation, etc.
How do those influence where you have to set the thermostat?
But indeed, 25 - 25.5 degrees Celsius is just about the most comfortable temperature (summer or winter).
How do those influence where you have to set the thermostat?
But indeed, 25 - 25.5 degrees Celsius is just about the most comfortable temperature (summer or winter).
My thermostat is located in a cooler part of my house compared to my bedroom -> my thermostat has to be set to 73 to cool my bedroom to a nice T.
If my AC is very large it wont run very long between cycles. When it does it will wring every bit of moisture out of that relatively small amount of air.
If the AC were smaller, the AC would run just about all day long, more of the air would then go get its moisture removed.
In other words:
1 unit of 4C air mixed with 9 units of 30C air -> 10 units 27.4C. Assuming I've removed all the water in the one unit of 4C air the water content has only gone down 10%
5 units of 24.8 C air mixed with 5 units of 30 C air -> 10 units of 27.4C. If I can get just 50% of the air out chilled 5 units of air, I've removed 25% of the water in the air.
These numbers are just thrown at you, so take them with a BIG grain of salt. You'd have to look at the water saturation tables to really do the math.
If my AC is very large it wont run very long between cycles. When it does it will wring every bit of moisture out of that relatively small amount of air.
If the AC were smaller, the AC would run just about all day long, more of the air would then go get its moisture removed.
In other words:
1 unit of 4C air mixed with 9 units of 30C air -> 10 units 27.4C. Assuming I've removed all the water in the one unit of 4C air the water content has only gone down 10%
5 units of 24.8 C air mixed with 5 units of 30 C air -> 10 units of 27.4C. If I can get just 50% of the air out chilled 5 units of air, I've removed 25% of the water in the air.
These numbers are just thrown at you, so take them with a BIG grain of salt. You'd have to look at the water saturation tables to really do the math.
In all the apartments I have lived (in the southern states), there was an AC that also works in reverse, it is called HVAC. However, in northern states, gas heating is cheaper than HVAC in the winter.
Kinda.
First some terminology.
HVAC mean Heating Ventilation and AC (i guess). It is the name for the general problem of dealing with the environment in the house.
Second, about the Northern states.
It really depends where you are and what your AC unit is.
Some heat pumps don't have the capacity to heat a house in the North. If they're sized just right for cooling, they wont be powerful enough to heat your home [1] . As a result these units will start using resistive heating (emergency heat) which is the worst way to heat your home.
Also, there is the edge case of extremely cold cities in the Midwest (Chicago is not cold enough). These cities have some days where the T can be -20F (about -30C). Not only does the COP start to plummet, the temperatures might be outside the operating range of the coolant.
So you do have to do your homework before you install a unit.
But I live in a Northern city now, with bad lows of 0F (-13C?) and the heat pumps work just fine.
[1] In the South if you size your heat pump for cooling, you're sized ok for the heating. Even if you get a few days below freezing triggering the emergency heat, that's not a big problem.
First some terminology.
HVAC mean Heating Ventilation and AC (i guess). It is the name for the general problem of dealing with the environment in the house.
Second, about the Northern states.
It really depends where you are and what your AC unit is.
Some heat pumps don't have the capacity to heat a house in the North. If they're sized just right for cooling, they wont be powerful enough to heat your home [1] . As a result these units will start using resistive heating (emergency heat) which is the worst way to heat your home.
Also, there is the edge case of extremely cold cities in the Midwest (Chicago is not cold enough). These cities have some days where the T can be -20F (about -30C). Not only does the COP start to plummet, the temperatures might be outside the operating range of the coolant.
So you do have to do your homework before you install a unit.
But I live in a Northern city now, with bad lows of 0F (-13C?) and the heat pumps work just fine.
[1] In the South if you size your heat pump for cooling, you're sized ok for the heating. Even if you get a few days below freezing triggering the emergency heat, that's not a big problem.
> I'm wondering if there's any low-energy or green solutions to this.
The answer is "it depends". How your flat is designed will have an impact on what you can do. But if you are able and willing to do some house work, there is a lot you can have control over.
At the end of the day, it's all about how you can control humidity, the flow of hot and cold air and humidity. At your disposal, tools such as conductive materials, insulating materials, etc. Google "passive house" to see the concept and what these things use.
With that said. Heat pumps are incredibly efficient, and replacing your heater with a reversible air conditioner which you can then run in both summer and winter will do far more for your overall energy efficiency than anything else you can do.
Most of your energy consumption comes from winter-time heating. Start here for a good introduction to heat pumps and how they are so efficient: https://www.youtube.com/watch?v=7J52mDjZzto
The answer is "it depends". How your flat is designed will have an impact on what you can do. But if you are able and willing to do some house work, there is a lot you can have control over.
At the end of the day, it's all about how you can control humidity, the flow of hot and cold air and humidity. At your disposal, tools such as conductive materials, insulating materials, etc. Google "passive house" to see the concept and what these things use.
With that said. Heat pumps are incredibly efficient, and replacing your heater with a reversible air conditioner which you can then run in both summer and winter will do far more for your overall energy efficiency than anything else you can do.
Most of your energy consumption comes from winter-time heating. Start here for a good introduction to heat pumps and how they are so efficient: https://www.youtube.com/watch?v=7J52mDjZzto
Here in Norway awnings that extend automatically to shield the window from the sun are an off the shelf item, they also retract automatically if the wind gets too strong.
This looks good, as my blinds kinda suck too!
There was an interesting article on heat pumps in the NY Times yesterday - they are similar to AC units but far more efficient, requiring far less electricity to run. Plus they work as heaters in the winter. I use heat pumps coupled to solar panels and draw very little power from the grid, if any.
https://www.nytimes.com/2021/06/30/climate/heat-pumps-climat...
https://www.nytimes.com/2021/06/30/climate/heat-pumps-climat...
Air conditioners are air source heat pumps.
Ya, Im very confused when people talk about heat pumps as separate from ACs. My new tenant got super excited when I used the word "heat pump" to refer to my AC.
One way heat pumps
Another term I've seen for "heat pump" is "reverse cycle air conditioner".
No, that implication is not universal in the term "air conditioner"
Windows shutters. There's a reason all those Italian charming villages have them.
http://www.shutterdesign.co.uk/blog/external-window-shutters...
http://www.shutterdesign.co.uk/blog/external-window-shutters...
Windows awnings: very good at keeping the sun out of a flat. You might have to ask your building manager for permission to install them though.
Ceiling fan
There's a lot of low-carbon climate control solutions ranging from relatively cheap and simple (though some require design from the get-go), to elaborate, but still easy compared to the overall task of home construction, that we just...don't use regularly and it baffles me.
I just stayed at a beach house in Florida for a bit and the walls are single-layer with zero insulation anywhere. The a/c runs basically 24/7. And this is apparently really common in the south. Like, do people think "insulation = makes inside warm" and not make the connection that it keeps warm out in the same way? It's a 1000sqft duplex bungalo that sold for like $800k at the trough of the housing bubble pop so like, materials/construction cost is a fraction of the value. Just like short-sighted decisions like this, everywhere.
Overall, the best solution is to design buildings in ways that facilitate passive temperature regulation, such as eaves over sun-facing windows that block high-angle direct sun, orienting and windowing the building so it's easy to get a cross-breeze in the prevailing wind (around here they love to put windows on the front/back and nothing on the sides, ugh) and locating such that deciduous trees are on the south side to block sun in summer but allow it in winter.
One of the easiest "retrofits" simply requires a programmable thermostat, even a manual one. Simply cool the building more overnight to build up a "store of cold".
I just stayed at a beach house in Florida for a bit and the walls are single-layer with zero insulation anywhere. The a/c runs basically 24/7. And this is apparently really common in the south. Like, do people think "insulation = makes inside warm" and not make the connection that it keeps warm out in the same way? It's a 1000sqft duplex bungalo that sold for like $800k at the trough of the housing bubble pop so like, materials/construction cost is a fraction of the value. Just like short-sighted decisions like this, everywhere.
Overall, the best solution is to design buildings in ways that facilitate passive temperature regulation, such as eaves over sun-facing windows that block high-angle direct sun, orienting and windowing the building so it's easy to get a cross-breeze in the prevailing wind (around here they love to put windows on the front/back and nothing on the sides, ugh) and locating such that deciduous trees are on the south side to block sun in summer but allow it in winter.
One of the easiest "retrofits" simply requires a programmable thermostat, even a manual one. Simply cool the building more overnight to build up a "store of cold".
That house was made to sell. If someone bought it, then the builder accomplished their goal. Unfortunately...
Everything is made for optimal profit, not optimal function.
Everything is made for optimal profit, not optimal function.
I would have thought these structures move air up and out by the [chimney effect](https://en.wikipedia.org/wiki/Stack_effect) instead of funneling air down as the article describes. I love my old house's double hung windows which also use the chimney effect for passive cooling by opening both sashes halfway. Cooler air comes in the bottom, and warm air goes out the top.
> I would have thought these structures move air up and out by the [chimney effect](https://en.wikipedia.org/wiki/Stack_effect) instead of funneling air down as the article describes.
That's what wikipedia describes—pulling cooled air from underground qanats up through the house and out the tower. I was surprised to read in this article about air coming down through them. Now I don't know which one is correct.
That's what wikipedia describes—pulling cooled air from underground qanats up through the house and out the tower. I was surprised to read in this article about air coming down through them. Now I don't know which one is correct.
Both, the tower doesn't have one opening on the bottom - it has two or four and they are separated by walls in the center. Wind is coming in from one direction and pushes cool air down into the building, hot air comes out the other side of the tower.
This article has a good visualization: https://surfiran.com/windcatcher-an-ancient-engineering-feat...
This article has a good visualization: https://surfiran.com/windcatcher-an-ancient-engineering-feat...
Wikipedia is equivocal about it (my highlight):
> The windcatcher can function in two ways: directing airflow using the pressure of wind blowing into the windcatcher, or directing airflow using buoyancy forces from temperature gradients (stack effect). The relative importance of these two forces has been debated.
> The windcatcher can function in two ways: directing airflow using the pressure of wind blowing into the windcatcher, or directing airflow using buoyancy forces from temperature gradients (stack effect). The relative importance of these two forces has been debated.
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If you're interested in low tech, passive and energy efficient technologies, I recommend the
LOW TECH MAGAZINE
For example, Revenge of the Circulating Fan: https://www.lowtechmagazine.com/2014/09/circulating-fans-air...
Frequently discussing topics like thermal comfort, energy needed to heat up a person, sustainability, solar-powered websites, mist showers, wind power, compressed air power, medieval methods of heating and what we can learn from them...
LOW TECH MAGAZINE
For example, Revenge of the Circulating Fan: https://www.lowtechmagazine.com/2014/09/circulating-fans-air...
Frequently discussing topics like thermal comfort, energy needed to heat up a person, sustainability, solar-powered websites, mist showers, wind power, compressed air power, medieval methods of heating and what we can learn from them...
The final comments on "AC architecture" are quite interesting. In my childhood home, the American South, pre-1950's housing is highly optimized for cooling. High ceilings, transoms, pier foundations, tin roofs, etc.
When Hurricane Katrina hit and left us without power for two weeks in the summer, sleeping in our normally comfortable home was nearly unbearable, even with every window open. The house simply was not designed for facilitating passive air flow. My friends, who lived in a rather dumpy 19th century "dogtrot" farm house, reported sleeping in relative comfort.
https://www.southernliving.com/home/dog-trot-house
When Hurricane Katrina hit and left us without power for two weeks in the summer, sleeping in our normally comfortable home was nearly unbearable, even with every window open. The house simply was not designed for facilitating passive air flow. My friends, who lived in a rather dumpy 19th century "dogtrot" farm house, reported sleeping in relative comfort.
https://www.southernliving.com/home/dog-trot-house
It appears you've read the article to the very end - I'm glad you've enjoyed it.
High ceilings - absolutely. Warm air goes up, can it get simpler than that? Primary/Elementary school physics.
If you watch some videos on lost African civilizations and traditional architecture, it's full of them (and curtains rather than doors). Some examples are Basil Davidson's "Africa" serries (on youtube, if you don't mind low quality) and I think Stefan Milo on his channel, the video about coral cities ("Swahili Culture").
Interesting experience with Katrina. You could call it having a house that "fails gracefully" and doesn't rely completely on any one system.
There are downsides to modern, well-isolated houses. When air is the primary medium of heating your house, opening a window means almost literally letting money out. Aside from crap like emissions from furniture (I believe they're called VOC - not a native speaker), dust, bacteria and fungal spores pile up. People develop allergy and respiration-related diseases more easily.
High ceilings - absolutely. Warm air goes up, can it get simpler than that? Primary/Elementary school physics.
If you watch some videos on lost African civilizations and traditional architecture, it's full of them (and curtains rather than doors). Some examples are Basil Davidson's "Africa" serries (on youtube, if you don't mind low quality) and I think Stefan Milo on his channel, the video about coral cities ("Swahili Culture").
Interesting experience with Katrina. You could call it having a house that "fails gracefully" and doesn't rely completely on any one system.
There are downsides to modern, well-isolated houses. When air is the primary medium of heating your house, opening a window means almost literally letting money out. Aside from crap like emissions from furniture (I believe they're called VOC - not a native speaker), dust, bacteria and fungal spores pile up. People develop allergy and respiration-related diseases more easily.
> High ceilings, transoms, pier foundations, tin roofs, etc.
How does a high ceiling help? Doesn't a high ceiling mean there's a larger volume of air in the room to cool? You'll also need a more powerful fan to move the extra air around.
How does a high ceiling help? Doesn't a high ceiling mean there's a larger volume of air in the room to cool? You'll also need a more powerful fan to move the extra air around.
A high ceiling _does_ mean that a modern A/C system has a larger volume of air to cool. And when people renovate high-ceiling houses, installing a "drop ceiling" is very common.
But when fans and cross-ventilation are the primary means of cooling, high ceilings allow the hottest air in the room to accumulate, where it will not bother occupants (and thus forcing cooler air into the occupied space near the floor).
But when fans and cross-ventilation are the primary means of cooling, high ceilings allow the hottest air in the room to accumulate, where it will not bother occupants (and thus forcing cooler air into the occupied space near the floor).
Hot air goes up
I prefer solar version of this website: https://solar.lowtechmagazine.com/about.html
Interesting.
On really hot days I’ve discovered that the most annoying thing is that the stuff I’m in contact with gets too hot. Sleeping ON a wet towel made all the difference.
On really hot days I’ve discovered that the most annoying thing is that the stuff I’m in contact with gets too hot. Sleeping ON a wet towel made all the difference.
How do you keep your bed from getting wet or do you accept the consequence?
I'm going to pursue cold showers at night on really hot days and try to keep the AC off or only kick on if the house temp is 85F.
I'm going to pursue cold showers at night on really hot days and try to keep the AC off or only kick on if the house temp is 85F.
I just accept the fact, I squeeze all the excess water out of the towel though, so it's not a big issue.
Cold showers didn't work for me, as you'll dry in like 15 minutes, and you are back to square one.
Cold showers didn't work for me, as you'll dry in like 15 minutes, and you are back to square one.
The damp towel and a light breeze can be amazing! Dries out in most environments too. Just flip the bed covers over and or set them aside and it all is set for the next evening, in my experience.
I think the parent might be suggesting that sleeping on a wet bed might trigger peeing reflex.
Eww. Never had an issue like that.
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You could buy a mattress cover maybe?
What a lovely website. Fun article about how old Thinkpads are indeed low tech nowadays as well.
Just found out one my favourite articles I discovered about Chinese wheelbarrows was also from this site!
https://www.lowtechmagazine.com/2011/12/the-chinese-wheelbar...
Just found out one my favourite articles I discovered about Chinese wheelbarrows was also from this site!
https://www.lowtechmagazine.com/2011/12/the-chinese-wheelbar...
That is a good one! Also worth noting, they host the site on an RPi running off solar power[1].
1: https://www.lowtechmagazine.com/2020/01/how-sustainable-is-a...
1: https://www.lowtechmagazine.com/2020/01/how-sustainable-is-a...
I believe these kind of passive systems only really work when the air is hot and dry (like in a desert). In hot and humid areas like South East Asia this system just doesn't work, sweating (evaporative cooling) isn't as effective when the air is already saturated with moisture.
I think you're underselling it a bit. Our ancestral heritage gives us sweating. If that doesn't work, we sort of fall back to fight or flight, with a racing heart rate. move the blood around as much as you can, and hope some part of the body can cool it.
Heat stroke is a real thing, and it's not fun. There seems to be automatic systems you can't think your way out of that make things worse. Fast heartbeat is burning more calories, adding heat, and friction from viscous blood adding more heat. I imagine it's a pretty unpleasant feeling. I tend to go into shock, so I get to dodge most of that horrible sensation.
Heat stroke is a real thing, and it's not fun. There seems to be automatic systems you can't think your way out of that make things worse. Fast heartbeat is burning more calories, adding heat, and friction from viscous blood adding more heat. I imagine it's a pretty unpleasant feeling. I tend to go into shock, so I get to dodge most of that horrible sensation.
How often are you going into shock from heat?!?
Rarely. Marathon training in summer, and being lazy about starting long runs early in the morning.
I'm pretty confident that I can say the incidence is not zero, but I'd agree it's less than 4.
this is over years. starting a multi hour run at 10 instead of 7 has some side effects. I'm not fast. I cover the distance. I've gotten into really weird headspace. I'm pretty good about tracking calories, so I'm pretty sure it was the heat from running when it's hot.
I'm pretty confident that I can say the incidence is not zero, but I'd agree it's less than 4.
this is over years. starting a multi hour run at 10 instead of 7 has some side effects. I'm not fast. I cover the distance. I've gotten into really weird headspace. I'm pretty good about tracking calories, so I'm pretty sure it was the heat from running when it's hot.
Heatwaves cause deaths and increased hospitalization at least in Europe. I presume it's not any better elsewhere.
You're right of the goal is to lower the temperature of the structure lower than the ambient temperature.
If the goal is simply to lower the temperature of the building to that of the wind, simple radiators such as those is perfectly fine.
Knowing that cities temperature is often a few degrees higher than that of the surrounding air, that would work in contemporary settings as well. But trees could play the same role more efficiently and with additional health and environmental benefits.
If the goal is simply to lower the temperature of the building to that of the wind, simple radiators such as those is perfectly fine.
Knowing that cities temperature is often a few degrees higher than that of the surrounding air, that would work in contemporary settings as well. But trees could play the same role more efficiently and with additional health and environmental benefits.
Not sure if it's possible to summon dang like this, but there is a dead sibling comment caught in the spam filter.
You're correct. Which prompts the question: are there any passive cooling methods that work in high humidity? Maybe just sheltering underground.
They alternatively can use the fact high up air is typically cooler (and dryer) than that at ground level.
[deleted]
Huh, I always thought these worked in reverse of what the article explains.
> First, as air is caught by the opening of a wind catcher, it is funneled down to the dwelling below, depositing any sand or debris at the foot of the tower. Then the air flows throughout the interior of the building, sometimes over subterranean pools of water for further cooling. Eventually, warmed air will rise and leave the building through another tower or opening, aided by the pressure within the building.
I thought that the wind at higher altitude passing through these tower openings causes a low pressure zone in the tower, which draws cooler air up from the basement/subterannean pool/qanat, through the building and out the tower. The pool or qanat is also open to the air at ground level further away from the main building, so that indrawn air has some time to dump heat into the underground/water.
> First, as air is caught by the opening of a wind catcher, it is funneled down to the dwelling below, depositing any sand or debris at the foot of the tower. Then the air flows throughout the interior of the building, sometimes over subterranean pools of water for further cooling. Eventually, warmed air will rise and leave the building through another tower or opening, aided by the pressure within the building.
I thought that the wind at higher altitude passing through these tower openings causes a low pressure zone in the tower, which draws cooler air up from the basement/subterannean pool/qanat, through the building and out the tower. The pool or qanat is also open to the air at ground level further away from the main building, so that indrawn air has some time to dump heat into the underground/water.
Same. I have seen these painted black at the top of the tower. The idea, as it was explained to me, was that the black paint would help heat the top, and that hot air would create negative pressure as it rises. The negative pressure then pulled up cooler air from below.
The photos show large vertical openings. Which makes more sense for ‘catching’ the wind. For a negative pressure a black painted vertical pipe would have been sufficient?
Passive heating and cooling is one of my favorite features of Earth Ships. I’m entirely enamored with the concept, but I don’t know how the climate impact of building these — better or worse than normal homes? You seem to make a lot of cement on-site.
Anyone have experience with these types of homes and can offer perspective?
https://www.earthshipglobal.com/
Anyone have experience with these types of homes and can offer perspective?
https://www.earthshipglobal.com/
If designed properly, climate impact should be far less than a normal home, that's one of the main points (aside from the long-term climate impact). Locally sourcing the materials is a big part. Many try to get super-hippy-dippy and rely on manual wall construction with heavy emphasis on rammed earth, I think this is great from an impact perspective, but not really scalable or appealing to a wider audience. But if concrete can be augmented with local dirt (I.e. concrete cavities filled with earth as a thermal mass), this is an excellent compromise. The tire/bottle walls are really dumb, people need to stop using them (unless you like the aesthetic I guess, or have way more time than money, or feel like financing a lot of medium-skill laborers).
Earthships as imagined by Michael Reynolds are super specific to New Mexico. The design works well there, but if you try those techniques in basically any other part of the country, you are gonna have a bad time.
I think the biggest takeaway from the philosophy is "actually think about design and construction based on the location, rather than what is common/easy." Stick-in-place construction is widely common in USA, even when that design is an antipattern in a climate (such as the southwest).
See: why the standard Earthship (tm) (yes it's a trademark, anything else is just Sparkling Sustainable Architecture) designs are a bad choice for cold climates.
https://www.ecohome.net/guides/1161/do-earthships-work-in-co...
tl;dr - they are a design stuck in the 70's in NM. Eco architecture has advanced significantly since then.
Earthships as imagined by Michael Reynolds are super specific to New Mexico. The design works well there, but if you try those techniques in basically any other part of the country, you are gonna have a bad time.
I think the biggest takeaway from the philosophy is "actually think about design and construction based on the location, rather than what is common/easy." Stick-in-place construction is widely common in USA, even when that design is an antipattern in a climate (such as the southwest).
See: why the standard Earthship (tm) (yes it's a trademark, anything else is just Sparkling Sustainable Architecture) designs are a bad choice for cold climates.
https://www.ecohome.net/guides/1161/do-earthships-work-in-co...
tl;dr - they are a design stuck in the 70's in NM. Eco architecture has advanced significantly since then.
Could you elaborate on eco architecture's advances? I always liked the idea of the earthship but, y'know, humidity.
Heat/enthalpy recovery ventilators are a big one. In New England, you want maximum insulation and minimum air leakage. Without mitigation, this leads to poor air quality. Therefore you want air changes, but you don't wanna vent all your heat (in winter, cold in summer), so you exchange heat between incoming and outgoing air.
HRVs only recover sensible (thermometer) heat but don't affect latent heat (humidity heat of vaporization) so there exist enthalpy recovery systems. However these run into icing problems in winter, when they would be most helpful. It's an area of active research.
Ground-source heat pumps are the best thing ever for temperate regions, since you can actually store heat/cold between temperature cycles and even seasons, but rather expensive to install, unless you are already putting in a leach field. I'm hoping for some advances in tech to make laying geothermal loops cheaper, I.e. cheaper and easier directional drilling.
E-glass (low emissivity) is increasingly popular. There's a cool trick where you have clerestory windows or skylights with e-coating to let in light but less IR. Then your south-facing regular windows have regular glass and big overhangs. This gives you year-round natural light and winter-only solar gain.
HRVs only recover sensible (thermometer) heat but don't affect latent heat (humidity heat of vaporization) so there exist enthalpy recovery systems. However these run into icing problems in winter, when they would be most helpful. It's an area of active research.
Ground-source heat pumps are the best thing ever for temperate regions, since you can actually store heat/cold between temperature cycles and even seasons, but rather expensive to install, unless you are already putting in a leach field. I'm hoping for some advances in tech to make laying geothermal loops cheaper, I.e. cheaper and easier directional drilling.
E-glass (low emissivity) is increasingly popular. There's a cool trick where you have clerestory windows or skylights with e-coating to let in light but less IR. Then your south-facing regular windows have regular glass and big overhangs. This gives you year-round natural light and winter-only solar gain.
Thanks for this; I always thought it seemed a bit too good to be true
If you live in a house with poor airflow, consider a whole house fan. Run it in the evening / overnight / morning with the windows open, then shut the windows (and shades if you don't mind the darkness) during the day.
There is an Ask This Old House episode where they install a whole house fan. [0]
Even if this doesn't remove the need for AC, it will decrease the load on the system by increasing how much heat the home's interior has to absorb before the AC kicks on.
We called these "attic" fans when we had one in the 1970s. They were huge, required a massive hole in the ceiling, and were loud. Modern ones are sound / thermally insulated, much smaller, require a smaller hole in the ceiling, etc.
[0] https://www.youtube.com/watch?v=Rwe8c6wr0AA
There is an Ask This Old House episode where they install a whole house fan. [0]
Even if this doesn't remove the need for AC, it will decrease the load on the system by increasing how much heat the home's interior has to absorb before the AC kicks on.
We called these "attic" fans when we had one in the 1970s. They were huge, required a massive hole in the ceiling, and were loud. Modern ones are sound / thermally insulated, much smaller, require a smaller hole in the ceiling, etc.
[0] https://www.youtube.com/watch?v=Rwe8c6wr0AA
From my previous research on whole-house fans, they are a wonderful device to have so long as you live in a place where the nights are cool, and most importantly, low-humidity. Unfortunately where I live and it’s 80+% RH at night, a whole-house fan would just give me mold.
Modern US houses, at least in much of the country, aren't built to be livable or to survive themselves without year-round temperature control. Partly, this is because optimizing for building survival and inhabitant comfort without AC and with only limited heating is at-odds with designing for efficient whole-house heating and cooling.
Notably, you don't want a very tight, low-outdoor-air-exchange envelope and tons of insulation in your walls if you're going AC-free and not also trying to start a mold farm. And if you want efficient AC you don't want tons of huge, openable windows on every single wall, at the end of every hallway, in all rooms, et c, nor an open, breezy attic (which helps a ton with temp control if you don't have AC, but is just wasteful if you've got it)
AFAIK design for minimizing AC power use and design for being able to tolerate not having AC are a "pick one, and only one" kind of thing.
[EDIT] Oh, and not strictly related to AC efficiency, but it takes a lot more skill and care in material selection to build a house that won't have all kinds of problems after just a few years of natural outdoor temperature swings, in the molding, flooring, even wall alignment & finishes (drywall, mostly, these days), so of course no-one bothers anymore—let the interior hit 90s in the Summer, swinging a bunch day-to-night, with high humidity, and parts that aren't near your heating source reach below-freezing temps at night in the Winter, and your interior will age at least 5 years for every 1 actual year, thanks to damage from huge amounts of expansion and contraction, unless it's designed to account for that. Ditto with aligning houses for optimal airflow, as far as the direction they face. Why bother, since it's always gonna have whole-house AC and heating? So no-one does.
Notably, you don't want a very tight, low-outdoor-air-exchange envelope and tons of insulation in your walls if you're going AC-free and not also trying to start a mold farm. And if you want efficient AC you don't want tons of huge, openable windows on every single wall, at the end of every hallway, in all rooms, et c, nor an open, breezy attic (which helps a ton with temp control if you don't have AC, but is just wasteful if you've got it)
AFAIK design for minimizing AC power use and design for being able to tolerate not having AC are a "pick one, and only one" kind of thing.
[EDIT] Oh, and not strictly related to AC efficiency, but it takes a lot more skill and care in material selection to build a house that won't have all kinds of problems after just a few years of natural outdoor temperature swings, in the molding, flooring, even wall alignment & finishes (drywall, mostly, these days), so of course no-one bothers anymore—let the interior hit 90s in the Summer, swinging a bunch day-to-night, with high humidity, and parts that aren't near your heating source reach below-freezing temps at night in the Winter, and your interior will age at least 5 years for every 1 actual year, thanks to damage from huge amounts of expansion and contraction, unless it's designed to account for that. Ditto with aligning houses for optimal airflow, as far as the direction they face. Why bother, since it's always gonna have whole-house AC and heating? So no-one does.
Tonnes of places here in Australia have whirlybirds [1] installed on their roofs to achieve a similar outcome, if I'm understanding correctly. Basically, it helps draw out hot air when there's an outside breeze to spin it, cooling the ceiling cavity and overall decreasing the temperature of the house.
[1]: https://duckduckgo.com/?q=roof+whirlybird
[1]: https://duckduckgo.com/?q=roof+whirlybird
The results I clicked on suggested that a solar PV system and an electric fan to do the same task make a bit more sense these days.
I think there's a few things like this where PV powered tech is probably the better option particularly as you can have one or the other running as necessary.
Warm dark night: pump the hot air out with mains electricity. Cold, windy, sunny day: turn the fan off and use the electricity for something else.
I think there's a few things like this where PV powered tech is probably the better option particularly as you can have one or the other running as necessary.
Warm dark night: pump the hot air out with mains electricity. Cold, windy, sunny day: turn the fan off and use the electricity for something else.
In a previous apartment I had Jerry-rigged a whole-house/attic fan by putting a box fan in the space where the hatch to the attic was. I used triple-wall cardboard and duct tape to make it the right size. It really helped pull air in from every open window, and because it was at the top of the steps it helped exhaust the hottest air in the house.
Box fans are not made for that type of application, but it worked. If I had to build my own again I would use a better fan, and use a smart home device to turn it on and off.
Box fans are not made for that type of application, but it worked. If I had to build my own again I would use a better fan, and use a smart home device to turn it on and off.
The version we had in the 1970s was basically this, but more industrial: a belt-driven fan in a minimal steel frame with a set of shutters that would open when the fan was on.
We definitely need to adapt building design to cope with higher temperatures. I live in a brand new building that has floor-to-ceiling triple-glazed windows on each side. They look great and let a lot of light in but the summer afternoons can be infernal — my WFH office can reach 32C, despite my best efforts to move air out with a large fan. I’m sure that with smaller windows or some kind of external shade the situation would be better.
The Persians are always asked to "westernize". Let's learn from them, too!
Lots of pre-industrial science and mathematics have been done in Persia. E.g.
https://en.wikipedia.org/wiki/Muhammad_ibn_Musa_al-Khwarizmi
(the dude called "Algorithm" was Persian)
https://en.wikipedia.org/wiki/Muhammad_ibn_Musa_al-Khwarizmi
(the dude called "Algorithm" was Persian)
Yep and then they decided religion is more important than science and stagnated to modern day... There's a lesson there.
Well, it's not that linear.
While renaissance started to steamroll west into the scientific future while the world of Islam stagnated, the story of Iran is far more complex than that of a continuous medieval theocracy which the brief statement above suggests (intended or not).
Before 1979 coup Iran was a more or less secular modern state and not a theocracy.
But it was destablized before that by the 1959 coup backed by UK and US interests.
https://en.wikipedia.org/wiki/1953_Iranian_coup_d%27%C3%A9ta...
https://en.wikipedia.org/wiki/Iran
While renaissance started to steamroll west into the scientific future while the world of Islam stagnated, the story of Iran is far more complex than that of a continuous medieval theocracy which the brief statement above suggests (intended or not).
Before 1979 coup Iran was a more or less secular modern state and not a theocracy.
But it was destablized before that by the 1959 coup backed by UK and US interests.
https://en.wikipedia.org/wiki/1953_Iranian_coup_d%27%C3%A9ta...
https://en.wikipedia.org/wiki/Iran
It wasn't a theocracy but it also wasn't anywhere close to the scientific powerhouse it was historically.
Which doesn’t mean it couldn’t have become one again.
As an outsider (non-Persian) I feel Iran would have been evolved into an interesting ally for the US in the long term, if we hadn’t meddled in their affairs all those years ago.
As an outsider (non-Persian) I feel Iran would have been evolved into an interesting ally for the US in the long term, if we hadn’t meddled in their affairs all those years ago.
Ironically simplifying it like you just did is one of the contributors to the diminished reverence for science in that part of the world.
There was a famous and nuanced published discourse between a philosopher named Al Ghazali and Averroes (Ibn Rushd) on the merits and failures of knowledge.
The observers of the discourse basically warped it into science vs. religion battle and as with all things with binary fanbases one school of thought had to prevail over the other. The delicate harmony between religion and knowledge shattered.
As the Middle East has learned and continues to learn the dangers of the spiritual ungrounded by knowledge, the West is now learning the dangers of knowledge unelevated by the spiritual.
There was a famous and nuanced published discourse between a philosopher named Al Ghazali and Averroes (Ibn Rushd) on the merits and failures of knowledge.
The observers of the discourse basically warped it into science vs. religion battle and as with all things with binary fanbases one school of thought had to prevail over the other. The delicate harmony between religion and knowledge shattered.
As the Middle East has learned and continues to learn the dangers of the spiritual ungrounded by knowledge, the West is now learning the dangers of knowledge unelevated by the spiritual.
> Ironically simplifying it like you just did is one of the contributors to the diminished reverence for science in that part of the world.
No, that was religion (or one particular religion) and its adherents. Remove the religion and the simplification ceases to be a factor, hence the simplification isn't really a factor, only what is necessary gets to be called a cause.
No, that was religion (or one particular religion) and its adherents. Remove the religion and the simplification ceases to be a factor, hence the simplification isn't really a factor, only what is necessary gets to be called a cause.
> the West is now learning the dangers of knowledge unelevated by the spiritual
Such as? Cause from where I stand it seems science is trying to save the world from global warming and spiritual leaders are busy protecting oil money and denying there's any danger :)
All the talk about "spiritual balance" eventually ends with "hate gays, oppress women, endorse slavery, kill nonbelievers". If that's the benefits of spiritual balance then good riddance.
Such as? Cause from where I stand it seems science is trying to save the world from global warming and spiritual leaders are busy protecting oil money and denying there's any danger :)
All the talk about "spiritual balance" eventually ends with "hate gays, oppress women, endorse slavery, kill nonbelievers". If that's the benefits of spiritual balance then good riddance.
If you credit science with "trying to save the world" from climate change, you also need to blame it for causing it in the first place. But it doesn't sound as impressive to solve a problem you caused in the first place, does it?
Science has been aware of the potential of increased CO2 emissions to cause heating of the atmosphere and hence global warming for a century. You can thank capital and politics not heeding this until now when the "risks" are becoming realities.
Special prize for energy companies for funding skepticism towards climate science because it was obvious 40 years ago that most of the oil we've dug out and burned really should have not been.
Special prize for energy companies for funding skepticism towards climate science because it was obvious 40 years ago that most of the oil we've dug out and burned really should have not been.
> you also need to blame it for causing it in the first place
I suppose. But scientific revolution reduced human suffering considerably by doing so, for example starvation in most of the world stopped and vaccination saved millions of lives. Science solves on problem, possibly causes another and then solves it, etc.
The problem with religion is that it only creates problems and invents justifications for why they are natural and good.
I suppose. But scientific revolution reduced human suffering considerably by doing so, for example starvation in most of the world stopped and vaccination saved millions of lives. Science solves on problem, possibly causes another and then solves it, etc.
The problem with religion is that it only creates problems and invents justifications for why they are natural and good.
Not that I consider you to be entirely wrong - but I suppose it depends on the definition of the spiritual tradition.
I am a non-expert on the topic, but I think for example Native-American spiritual tradition has always considered industrial scale modification of the natural environment as a bad thing.
I am a non-expert on the topic, but I think for example Native-American spiritual tradition has always considered industrial scale modification of the natural environment as a bad thing.
Persians were pretty religious (Zoroastrianism, etc.) in the ancient days too. It was just not Islam. And the way Persia has changed and evolved and what has happened there goes beyond the simple "they decided religion is more important".
Here is Asia old-style houses have a central atrium. Above most windows are holes. The entire apparatus acts like a chimney, sucking air through the house.
It was also common to place a large tub of water near an outside door. As it evaporated, it sucked air through the house, improving through-flow of air.
It was also common to place a large tub of water near an outside door. As it evaporated, it sucked air through the house, improving through-flow of air.
Is there a specific school of design (or something I can Google) about low tech architecture designed for high temperatures?
I live in Phoenix and while I’m sure this wind catcher technology would help in the months leading up to and following summer, having a 110° pushed through a house doesn’t sound optimal. I am very interested in the field though! Maybe there’s something that would work even here.
I live in Phoenix and while I’m sure this wind catcher technology would help in the months leading up to and following summer, having a 110° pushed through a house doesn’t sound optimal. I am very interested in the field though! Maybe there’s something that would work even here.
I suppose The Barefoot Architect by Johan van Lengen[0] is a nice introduction to low-tech solutions for enthusiasts. The caveat is that I loved reading the ideas in it but never got around to try any of them, so I can't vouch for how it works out in practice.
[0] https://www.lloydkahn.com/2007/11/barefoot-architect-handboo...
[0] https://www.lloydkahn.com/2007/11/barefoot-architect-handboo...
I achieve the same results with a whole-house fan run at night, foil-bubble-foil, spray foam insulation and insulated white-backed window curtains. The summer procedure is to power up the fan and open the windows at sundown, then reverse the procedure at sunup. When the paulownia trees reached 40 ft. in 3 years, we only run the AC a couple of hours in the afternoon to maintain a 76 degree environment. This is in North Carolina at about 900 feet elevation. It's a 3 story 2700 square foot house with Hardieboard (thin concrete) siding. You might call BS, but my electric co. and propane co. are very disappointed.
A better way to both heat and cool a building passively is the Skytherm Roof: https://www.google.com/search?rlz=1C1GIGM_enUS553US553&sxsrf...
https://www.architectmagazine.com/technology/harold-hay-skyt...
https://www.architectmagazine.com/technology/harold-hay-skyt...
I just installed window anti-sun foil in bedroom and it works suprisingly well. I found one that doesn't change perceived light and might also add it to my office and not use AC at all.
I’ve always been interested in these, but the environmental cost to them is higher than the article would suggest: they’re emission free during use, for sure, but their construction represents a significant use of carbon.
They look attractive when compared with AC systems, but that’s an apples to oranges comparison - they can’t get nearly as cool as AC, and they can’t protect people on days with dangerous heat levels. When compared with a closer equivalent, fans, they are much less attractive in terms of energy savings.
They look attractive when compared with AC systems, but that’s an apples to oranges comparison - they can’t get nearly as cool as AC, and they can’t protect people on days with dangerous heat levels. When compared with a closer equivalent, fans, they are much less attractive in terms of energy savings.
From the article:
“The US too has adopted wind-catcher-inspired designs with enthusiasm. One such example is the visitor center at Zion National Park in southern Utah.“
It is just a small one storied house built in the 70s. I don’t think or see any modern day buildings having wind catchers built into them. Almost all of them have central AC and duct system. I therefore think the authors comment is a bit exaggerated as far as enthusiasm for such environmental friendly solutions in USA are concerned.
“The US too has adopted wind-catcher-inspired designs with enthusiasm. One such example is the visitor center at Zion National Park in southern Utah.“
It is just a small one storied house built in the 70s. I don’t think or see any modern day buildings having wind catchers built into them. Almost all of them have central AC and duct system. I therefore think the authors comment is a bit exaggerated as far as enthusiasm for such environmental friendly solutions in USA are concerned.
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For buildings with central heat/air built in, I've often wished there was an additional function to either pull outside air into the system, or exhaust the air from the air return outside, ideally both. It seems like with all the ducting installed and a powerful furnace fan this would get you a lot of extra functionality with minor additional cost.
My home has an air circulator that’s designed to pull in fresh air every hour.
As it’s drawn in it passes through a heat exchanger so the air coming in is nearly the same temperature as the air inside the house.
This means the house stays cool/warm without much addictions energy required.
I’m sure larger buildings have similar features but it’s a really great system to have if you find yourself building a new home.
As it’s drawn in it passes through a heat exchanger so the air coming in is nearly the same temperature as the air inside the house.
This means the house stays cool/warm without much addictions energy required.
I’m sure larger buildings have similar features but it’s a really great system to have if you find yourself building a new home.
I've heard of those devices before, but is there any way to bypass the heat exchanger section, like when the outside temperature is more preferable?
Most people just open the windows for that use case: a whole house fan can be used for making the air exchange faster through.
You can turn it off or run it less frequently.
This reminds me of the cooling systems used by termites:
https://www.nytimes.com/2019/03/26/science/termite-nest-vent...
https://www.nytimes.com/2019/03/26/science/termite-nest-vent...
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Since nobody else posted it:
https://en.wikipedia.org/wiki/Sekanjabin
https://en.wikipedia.org/wiki/Sekanjabin
I remember reading somewhere, that the Aztecs built small windows in a specific way, on the top of the walls, in order to cool their houses. Does anyone have further info on that?
While the architecture is clearly looking different, you might think of Sudano-Sahelian architecture (https://en.wikipedia.org/wiki/Sudano-Sahelian_architecture)
Mesoamericans as a whole, including nahuas, did not typically build windows. Some south American groups did, but not high up on walls or for cooling. Perhaps you're thinking of something else like mashrabiya?
I'm sure it isn't mashrabiya, it looked differently - it was thin (almost a horizontal slit), and I think its purpose was to "conduct" the hot air without letting the rain to come in.
According to the article these wind catchers are called bâdgîr in persian. Interesting that the arabic word for this transmorphed into bârgîl.
If it's not too humid, almost anything that provides airflow and shade will work. If it's too humid, it won't.
This is really amazing to learn how the ancient civilizations handled the warm weather.
I hope we can use this further in warm countries!
I hope we can use this further in warm countries!
One of the links to wind cowls in London suggests they finally found a peaceful use for the Daleks!
the base is under a salt!
Fans are environmentally cheap to run.
Compressors not so much.
Worth remembering when armchair-reengineering the world.
Compressors not so much.
Worth remembering when armchair-reengineering the world.
These techniques were the best ancient technology could manage, but wouldn't satisfy most people today.
The initially described version can bring your house down to the temperature of high up air (ground level air might be 50C because the surface of the ground is heated a lot by the sun, whereas air 10 meters up is much cooler).
The version with water cooling can bring your house down to the wet bulb temperature of high up air.
But modern people expect a temperature lower than both of those using refrigeration. And then they keep that coolness in using good insulation (neither of which were available in the ancient world).
The initially described version can bring your house down to the temperature of high up air (ground level air might be 50C because the surface of the ground is heated a lot by the sun, whereas air 10 meters up is much cooler).
The version with water cooling can bring your house down to the wet bulb temperature of high up air.
But modern people expect a temperature lower than both of those using refrigeration. And then they keep that coolness in using good insulation (neither of which were available in the ancient world).
> And then they keep that coolness in using good insulation (neither of which were available in the ancient world).
Good insultation to keep cool in summer and warm in winter used to be provided by thick stone walls, which have quit some thermal inertia.
Just look at traditional houses in Southern Europe, for example. They are cooler than 'modern' houses because of that and because people nowadays insist on having a lot of glass (large windows, large patio sliding doors, etc), which turns buildings into greenhouses (and walls are thinner)... and then people install air-con to compensate.
Good insultation to keep cool in summer and warm in winter used to be provided by thick stone walls, which have quit some thermal inertia.
Just look at traditional houses in Southern Europe, for example. They are cooler than 'modern' houses because of that and because people nowadays insist on having a lot of glass (large windows, large patio sliding doors, etc), which turns buildings into greenhouses (and walls are thinner)... and then people install air-con to compensate.
Traditionally houses didn't have a lot of windows because glass wasn't as good as it is today when it comes to insulation. Triple glazed windows are becoming a standard in a lot of places.
People also didn't spend that much time indoors because they didn't have anything to do. Times have changed and the needs of the people have changed.
Walls being thinner nowadays is due to the advances in options available for construction & insulation, not to mention safety standards. Modern ceramic bricks with air pockets + 10cm of polystyrene on the outside for insulation is insanely efficient for most residential establishments.
Walls being thinner nowadays is due to the advances in options available for construction & insulation, not to mention safety standards. Modern ceramic bricks with air pockets + 10cm of polystyrene on the outside for insulation is insanely efficient for most residential establishments.
I may be wrong but I feel thick stone walls are a bit like having large buckets of water in a greenhouse: They regulate temperature, whereas modern insulated walls don't because they are indeed just very good insulators.
As for double or triple glazed windows, they are good at keeping the heat in but in my experience they are not that good at keeping the heat out: sunlight gets in and heats up surfaces, the whole room warms up, and then the heat is trapped.
A traditional way to try to keep cool in Southern Europe is to open the windows to create airflow while closing the shutters to keep sunlight and heat out. Now, of course this makes rooms quite shady. Villages completely quiet with shutters closed during 'siesta' are famous to the point of stereotype but that's a real adaptation: Stay cool and avoid efforts during the hottest part of the day.
As for double or triple glazed windows, they are good at keeping the heat in but in my experience they are not that good at keeping the heat out: sunlight gets in and heats up surfaces, the whole room warms up, and then the heat is trapped.
A traditional way to try to keep cool in Southern Europe is to open the windows to create airflow while closing the shutters to keep sunlight and heat out. Now, of course this makes rooms quite shady. Villages completely quiet with shutters closed during 'siesta' are famous to the point of stereotype but that's a real adaptation: Stay cool and avoid efforts during the hottest part of the day.
Or adobe, as used in the US southwest.
I have been there in a few of these buildings that use wind catchers. I can say that, as a modern day human, these work pretty well in their dry weather! I can that see you've never experienced it and maybe your skepticism is a result of that, but your reasoning is not sound.
For example, a significant number of "modern people" here in Germany don't have AC in their households. Point being, there are different people in the world with different conditions and not everyone expects the exact same thing. Also insulation is not a product of the modern world. We just now have modern methods for it.
For example, a significant number of "modern people" here in Germany don't have AC in their households. Point being, there are different people in the world with different conditions and not everyone expects the exact same thing. Also insulation is not a product of the modern world. We just now have modern methods for it.
All that changed when concrete was imported to reduce thermal efficiency and the CO2 emissions related to producing concrete and the non-stop air conditioning / heating as a result. In stark contrast to the original designs going back millenia, it's always been laughable to me that countries like Saudi (King Abdullah Economic City), Egypt, or UAE think they can build way out into the desert and not suffer the repercussions of the sun's relentlessness in shiny glass and metal buildings.
1 - https://en.wikipedia.org/wiki/Vernacular_architecture#Climat... 2 - https://en.wikipedia.org/wiki/M%27zab