Switzerland's ingenious cooling caves | Hacker News Reader

Switzerland's ingenious cooling caves

bbc.com

89 pointsHooke43 comments

You find these earth cellars in many places across Europe, even today. Often they're built into hillsides. Also, in Europe many old houses still have similar cellars without artificial flooring, which tend to be much better for preserving food. My grandma would e.g. fill up an entire room in her cellar with apples in autumn and they would keep well (apart from slightly shriveling) for an entire year.

And bonus points if you have a creek uphill that you can divert to the top of a vertical chute in your tunnel system to send it over a drip-grid when temperatures are slightly freezing: not too cold to have the creek still running, but cold enough make the water form icicles from the drip grid. Pass by once a day to kick down newly formed icicles, building an ice reservoir at the bottom of the chute. I know a brewery that solves all their cooling needs with this method.

(no idea if they reinstated that system in the oughts, when starting to advertise as "all renewable", or if they just failed to update to electric refrigeration long enough that it eventually became fashionable again - hardly more than a century of "yeah, perhaps next year, I'm busy!")

Sounds interesting, but I'm not sure if I understood correctly. Can you provide an illustration?

Edit: yeah, totally the wrong thread, sorry. Implementation of the icicle thing is really simple, divert the creek (or parts of it) onto a wooden contraption that would split it into many small trickle-streams. Trickle streams small enough to make them freeze into icicles. Occasionally, take some plank or pole to bang the icicles off the wooden contraption, this needs to be done before they grow so heavy they overload the frame. Have a cellar/chute deep enough to not fill up to the top in of winter. Do a Google image search for eisgalgen (none of the examples are from a natural stream and also no directly above the chute implementations)

(original reply) In Excel, a cell with a formula has two faces, the formula and the result. An implementation of "plain csv, but with a way to run formulas" could simply branch out to using separate files, particularly if you already have an a UI that's good at working with more than one file. Technically, the additional input file would be unnecessary, because all input data could all be in the formula file, with some shorthand for "identity transformation".

(still original wrong thread reply, nothing new below) The more I think about it, the "hashbang part" could even be designed to work as an actual script, sending the file (or files) to an interpreter that produces the result stream to stdout. Add an interface for doing cell by cell interactive updates and you'd have full independence between the implementations of UI and formula syntax.

Posted in the wrong thread, I assume? The relation between Excel cells and beer-cooling icicles is tenuous at best.

Thanks, now my mind is going through a what-if where Clippy is educating us about natural all-year beer cooling techniques!

You've never had an Excel formula freeze the computer?

Only when it involves large amounts of negative numbers.

You find them in old houses in the US, too. They’re called “root cellars”, and generally have dirt floors with brick walls. They do work surprisingly well. I live in a hot part of the US, and those cellars are like heaven in the summer.

Indeed. In Cologne, which has quite a beer-brewing tradition, there are even humongous deep and large cellars, where they stored ice and cooled the beer barrels for later sale. Some of them are as large as a basketball court and today they make nice party locations - there is no way the sound gets to the surface, so you can make any noise without aggravating neighbors :)

We keep apples at room temp for up to a year in our house, too — no basement/cellar. They just keep really well. (Seattle.)

>You find these earth cellars in many places across Europe, even today.

Weren't these the original "wine cellars"? :-)

My great grandfather did the same thing with potatoes, sweet potatoes, and cabbages in Louisiana. He would plant enough of both for a year and keep them in a dug-in shed with a soil floor. I'll never forget the smell of the soil coming off of the veggies as we pulled them out for eating.

For those saying "they're all over the world", it's not clear from the article but there's literally wind flowing from inside the mountain and that's flowing all year around at ~10°C, even during summer when it's 35C outside. I live in a valley nearby, but in Italy, we have them too. I'm not aware of similar places elsewhere, at least not at the scale we have them here (every little town has their own place where they found the cool air flowing out). Built centuries ago, they're still used to store wine by the old people in town. Sometimes I go there to cool down in summer. Very different from a cellar.

> there's literally wind flowing from inside the mountain and that's flowing all year around at ~10°C, even during summer when it's 35C outside

Could you clarify? What do you mean by wind flowing from inside the mountain?

From the article: "The reason grottos worked so well as natural fridges is due to their excellent ventilation. Since they usually occurred on rockfall or on an accumulation of scree, they have a porous foundation that guarantees internal air circulation and results in a year-round stable temperature..."

I think more information is required to explain how porous scree leads to wind blowing out of the grotto

Maybe rocks in the scree cool down the air in the pores between them. Cool air is denser so it sinks and flows out at the bottom of the porous layer, and new warm air is pulled into the ground towards the top of the scree pile. People found the places that cool air was flowing out and built these grottos there. Not saying I knew anything about these before 10 minutes ago, but that seems plausible to me.

Hey, I think it is an interesting concept and open to to ideas. Thanks for your ideas, my engineering brain would just love a picture of the physics

IANAGeologist, but my understanding is that when a steady wind blows from underground it's often due to a naturally occurring trompe: water flowing underground entrains air bubbles which collect in caverns and leak back to the atmosphere. Trompes can be quite large.

https://en.wikipedia.org/wiki/Trompe

We just need these in Manhattan! LoL

Seriously, the concrete jungle is a big pain for cooling because the cement absorbs heat and radiates it, so after a few hot days in a row it's really tough to cool sans A/C. If the power went out, I'd probably go to the basement? But if it were out for a week+, pretty sure we'd recreate an urban version of The Ministry for the Future. :-(

Does Manhattan suffer from heat soak in the underground?

I know in London, the Underground has generated so much heat over so many years, it no longer cools in Summer but instead retains heat overnight meaning it's sweltering even deep underground in many stations for much of the year. https://www.ianvisits.co.uk/articles/cooling-the-tube-engine...

It's always somewhat surprising to me that given a bit of time, a seemingly inexhaustible resource like heat capacity of the ground or ground water can actually be depleted once we put our minds to using it.

  > It's always somewhat surprising to me that given a bit of time, a seemingly inexhaustible resource like heat capacity of the ground or ground water can actually be depleted once we put our minds to using it.

Or the ability of the atmosphere to just "disappear" all that ICE exhaust.

The NYC subway is pretty much all cut-and-cover and doesn't have many tunnelled parts like the deep-level Tube lines.

Toronto uses the [Deep Lake Water Cooling System](https://en.wikipedia.org/wiki/Deep_Lake_Water_Cooling_System) to extract "cold" from lake water before it is treated and used for drinking water.

Sucks for the “free” cooling we get from cool tap water.

Takes a little load off the water heater I do have to admit. Unless you have a heat-pump based system, which is the trend…

It has nothing to do with tap water, they provided false information. It is pulling cold water from the lake, running it through heat exchangers throughout the system, then the cold liquid at each system is used to cool the buildings, etc. The slightly warmer water goes back into the lake, not into the drinking water system.

Incorrect. The heat exchangers are a part of the city water intake.

Edit: looks like a bit of both? See pg. 6:

https://www.toronto.ca/wp-content/uploads/2020/05/963d-ppfa-...

Though the city drinking water is pulled from deeper out so probably that supply is cooler to begin with:

https://www.toronto.ca/wp-content/uploads/2020/05/963d-ppfa-...

It is not used for drinking water, and the link you shared also doesn't mention that, but it is an interesting system that should be used in more places.

This appears to be somewhat of a naturally-occurring yakhchal: https://en.wikipedia.org/wiki/Yakhchāl

Something I've always rated quite highly as far as ingenuity goes.

this look nice, but I don't understand what is special in swiss caves, as far as I can tell everyone in the world who had access to caves and produced anything perishable did the same.

I'm at least aware of similar things in Italy, Spain and Hungary, it does not seems particularly ingenious.

These cellars use natural properties of the terrain. In Switzerland, there are many places where it is naturally colder than the rest of the environment. At the foot of rubble slopes it is often colder because inside the rubble the air can sink and cool down. The water present in the rubble evaporates, contributing to the cooling. In earlier times, buildings were built where the cold air escapes from below, which then served as natural refrigerators.

There are still such cellars in my area. Here is an article with pictures about it (in German): https://www.gasthaus-kreuz.ch/Archiv/reportagen_bierchaeller.... It is likely that comparable natural phenomena have been used in other countries as well.

This is about a scree slope near Ticino -

The scree acts like a chimney during the cold winter periods. Warm and light air is expelled out of the upper part of the scree and is replaced by cold and dense air aspirated inside the lower part of the slope. The process leads to the overcooling of the scree in winter and to the occurrence of permafrost

In summer, the chimney effect is reverse and the permanent expiration of cold air prevents the vegetation from growing normally.

https://www.arlis.org/docs/vol1/ICOP/55700698/Pdf/Chapter_03...

"Near Ticino" is relative. ;) This article is about a famous rocky cirque in the french part of Switzerland, so a completely different region, in Swiss scales. However, around 150 km and some high mountains apart. Interesting article, thanks!

> It is likely that comparable natural phenomena have been used in other countries as well.

That’s exactly what the parent comment is saying no?

This is literally part of the legendary origins of Roquefort cheese (the Roquefort Caves, which have a few more peculiarities like the “fleurines”, faults in the rock which provide ventilation to the caves, further improving temperature and humidity regulation and stability).

Kinda ironic to see Roquefort cheese in an example of natural cooling and preservation system :)

In the US, one would often put up a stone outbuilding around a spring in a hillside, to be a refrigerator. These were "spring houses."

Be that as it may, but the article you linked actually confirms that places like this exist all over the world: "Kaltluftlöcher wie jenes im ‚Bierchäller’ sind der Menschheit seit jeher bekannt und wurden überall genutzt" ("cold air holes like the one in the "Bierchäller" have been known for a long time and were used everywhere"). Because warm air rises up, cold air tends to accumulate in holes in the ground. That's how an ice cave can form in the not very high and not very cold mountains of Romania (https://en.wikipedia.org/wiki/Sc%C4%83ri%C8%99oara_Cave).

In Germany (particularly Bavaria), the ground above the beer cellars was planted with chestnut trees to provide shade and help keep the cellar cool during the summer. Which was also an excellent shady place to serve the beer. For the sake of simplicity, the customers were allowed to bring their own food - thus the Bavarian beer garden.

It worth also looking to Matmata's underground houses. They will definitely be familiar if you watched Star Wars.

https://www.atlasobscura.com/places/matmata-underground-hous...

This article ommits the most important details: what are the (average) temperature, and relative humidity in those grottos?

You need around 15-17°C (59-62.6°F) and 75-90%, respectively to age cheese.

Incidentally, I think it's the same for wine, at least for the temperature. I think relative humidity of ~60% is only needed in bottled wine and that only to avoid the corks drying out.

Ehm, that's not specifically of Swiss, nor Canton Ticino, in the whole world we have used for centuries "advantageous micro-climate places", sometimes even for living, sometimes just to preserve foods or something else, sometimes thanks just to specific orography, sometimes artificially made with various design.

We talk about that now because of the looming crisis and a kind of (largely absurd) "what we can do with nothing tech", generally forgotten that we do not produce foods locally, like in the past, so even re-learning long lost or long-marginal tech and techniques we simply can't do much with them...

Honestly: if someone is warred by loss of electricity == loss of fridges/freezers a small p.v. or other personal renewable is the option so far, learning to cook and preserve at home is another, but going further is not a realistic option.

I am currently reading Kim Stanley Robinson's "Ministry of the Future" and these seem like a great thing to have in the future, when heat waves might be so extreme at times, that they threaten survival.

Didn't Switzerland pull shit like literally put explosives around bridges and data links so if someone invades people could, quite literally "go to the mattresses"?

I heard lots of stories like that from people who would claim they have friends in GCHQ or whatever as I'd repeatedly remind folks I have never filled out an SF-86, I'm literally just some guy that people with TS:SCI clearances have talked too much in front of since childhood.

I worry that kind of movie plot threat modeling is why you saw what happened in Texas, repeatedly:

https://stateimpact.npr.org/texas/tag/2011-blackouts/

https://www.npr.org/2021/02/16/968230163/millions-without-po...

People made decisions that seemed right at the time, but didn't factor in the costs, in all senses of the word, of upkeeping a complex defense system with physical components that may... decay.

You cannot do things like maintain a separate power grid to make it easier to secede, then pair that with no state income tax to ensure upkeep of your parallel infrastructure, or your people will die in large numbers, multiple times, as some Glasnost loving, chicken fingers addicted autist repeated comes onto The Website to remind folks: you were told that exactly this scenario, on this day, would happen if you ignored the warnings delivered in person, face to face, repeatedly, for over a decade, of the consequences of your decisions.

Now, wall of text aside, this is a fascinating article. My hometown can get into the 90s with high humidity, but has abundant caves if you know where to go (we used to mine coal more than we do now), so I find this kind of writing extremely educational, and I thank the OP for pointing me to it.

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