The Ancient Persian way to keep cool
bbc.com
bbc.com
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
…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.
Good luck with that.
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.
“ 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.”
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.
I expect we will continue to do so and continue to make bad decisions.
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.
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.
And that’s per floor.
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
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.
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.
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.
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.
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.
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."
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.
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.
"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...
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.
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?
"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
ETA: Also one of the few scrabble words with a "q" but no "u" :-)
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 :-/
https://www.nytimes.com/2021/06/30/climate/heat-pumps-climat...
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
http://www.shutterdesign.co.uk/blog/external-window-shutters...
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].
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
"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.
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.
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.
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).
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.
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???
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 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".
Everything is made for optimal profit, not optimal function.
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.
This article has a good visualization: https://surfiran.com/windcatcher-an-ancient-engineering-feat...
> 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.
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...
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.
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.
Cold showers didn't work for me, as you'll dry in like 15 minutes, and you are back to square one.
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...
1: https://www.lowtechmagazine.com/2020/01/how-sustainable-is-a...
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.
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.
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.
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).
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.
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.
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.
> 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.
Anyone have experience with these types of homes and can offer perspective?
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.
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.
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.
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.
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.
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.
https://en.wikipedia.org/wiki/Muhammad_ibn_Musa_al-Khwarizmi
(the dude called "Algorithm" was Persian)
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...
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.
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.
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.
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.
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.
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.
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.
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.
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.
[0] https://www.lloydkahn.com/2007/11/barefoot-architect-handboo...
https://www.architectmagazine.com/technology/harold-hay-skyt...
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.
“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.
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.
https://www.nytimes.com/2019/03/26/science/termite-nest-vent...
I hope we can use this further in warm countries!
Compressors not so much.
Worth remembering when armchair-reengineering the 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).
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.
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.
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.
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.