6 ms·

I see frequent mentions of AI wasting water. Is this one such setup, perhaps with the CDU using the facility's water supply for evaporative cooling?

deleted 1y ago
[deleted]
bri3d 1y ago
The CDU is inside the datacenter and strictly liquid to liquid exchange. It transfers heat from the rack block's coolant to the facility coolant. The facility then provides outdoor heat exchange for the facility coolant, which is sometimes accomplished using open-loop evaporative cooling (spraying down the cooling towers). All datacenters have some form of facility cooling, whether there's a CDU and local water cooling or not, so it's not particularly relevant. The whole AI-water conversation is sort of tiring, since water just moves to more or less efficient parts or locations in the water cycle - I think a "total runtime energy consumption" metric would be much more useful if it were possible to accurately price in water-related externalities (ie - is a massive amount of energy spent moving water because a datacenter evaporates it? or is it no big deal?). And the whole thing really just shows how inefficient and inaccurately priced the market for water is, especially in the US where water rights, price, and the actual utility of water in a given location are often shockingly uncorrelated.
- maartin0 1y ago
  Slightly old but interesting https://blog.equinix.com/blog/2024/09/19/how-data-centers-use-water-and-how-were-working-to-use-water-responsibly/ https://blog.equinix.com/blog/2024/09/19/how-data-centers-us...
- deleted 1y ago
  [deleted]
- bjackman 1y ago
  Even without AI the whole water conservation topic is kinda silly. The margin at which it makes sense to save water varies wildly by location, but the cultural dominance of the western USA infiltrates everything. Here in Zürich, my office briefly installed water saving taps. This is a city of less than half a million where the government maintains 1,200 fountains that spew drinkable water 24/7. But someone at the California HQ said saving water is important and someone at the Swiss subsidiary said yes sir we'll look into it right away sir.
  - acyou 1y ago
    It's on the same level as people using incandescent light bulbs. Well we clear 160k Euros after taxes and have public medical care, and electricity is 10c/kWh here, so why does it matter what bulbs we use? We live in an area surrounded by grass fed cows, so what does it matter if we throw away 3/4 of our steak? Without regard to how plentiful resources are in our particular area, being needlessly wasteful is in bad taste more than anything. It's a lack of appreciation of the value of what we have. For water specifically - it is generally speaking the most valuable resource available, we just don't appreciate it because we happen to have a lot of it.
    - MindSpunk 1y ago
      While I'm not saying waste when things are plentiful in general is okay, I think water is a unique case that can be treated differently. Comparing to energy costs isn't the same because using the energy for the incandescent bulb consumes that energy permanently. The gas/coal/fuel can't be un-burned. Although solar changes this as the marginal cost of that energy is free. Comparing to food is similar. Once the food is wasted it is gone. Water is typically not destroyed, it's just moved around in the water cycle. Water consumption in a region is dictated by the throughput the water cycle replenishes the reservoirs you're pulling from. "Waste" with water is highly geographic, and it's pretty reasonable to take exception to California projecting their problems to geographic regions that they aren't important.
      - fennecfoxy 1y ago
        It still takes energy, chemicals and therefore pollution to clean water once it's been turned into greywater.
        ignaloidas 1y ago
        Sun is continuously running a very nice distillation cycle the size of the world that makes fairly clean water just fall out of the sky. It's only a question of where does it fall, and how much. If you want it even cleaner, wait a couple centuries for it to filter down underground, and get it from there - besides maybe a bit high mineral contents, that can easily be removed, it's essentially free, clean water. The only question is how much it's replenished in the area you're taking it from. There's plenty of areas where there's more rainfall, than there is outflow/evaporation, with water continuously replenishing deep groundwater. "Saving water" in such areas is of little concern besides the basic, economic one of well maintenance - each one can only pull so much, and more usage means more wells, and more upkeep.
jeffbee 1y ago
[flagged]
- wredcoll 1y ago
  I looked very hard but I don't see a way to subscribe to your newsletter?
- stripe_away 1y ago
  > there is a massive influence operation that seeks to destroy knowledge, science, and technology in the United States Agreed. Started with big tobacco by discrediting the connection to lung cancer, playbook copied by many and weaponized by Russia. > There is no subjective measure by which the water used by AI is even slightly concerning. Does not follow from your first point. The water has to be sourced from somewhere, and debates over water rights are as old as civilization. For one recent example, see i.e. https://www.texaspolicy.com/legewaterrights/ https://www.texaspolicy.com/legewaterrights/ You are probably correct that the AI does not damage the water, but unless there are guarantees that the water is rapidly returned "undamaged" to the source, there are many reasons to be concerned about who is sourcing water from where.
- deleted 1y ago
  [deleted]
- deleted 1y ago
  [deleted]
- bryan_w 1y ago
  Ayyo chill. Don't let on that you know their plans. People aren't ready to know about the operations yet, so you'll come across as off balanced
- williamdclt 1y ago
  It doesn't even pass the sniff test because the "AI wasting water" argument comes from liberals based on ecological concerns, whereas the systematic attack on knowledge/science comes from conservatives who explicitly do not give a crap about ecological concerns
Lerc 1y ago
I have encountered a lot of references to AI using water, but with scant details. Is it using water in the same way a car uses a road? The road remains largely unchanged? The implication is clear that it is a waste, but I feel like if they had the data so support that, it wouldn't be left for the reader to infer. I can see two models where you could say water is consumed. Either talking about drinkable water rendered undrinkable, or turning water into something else where it is not practically recaptured. Tuning it into steam, sequestering it in some sludge etc. Are these things happening? If it is happening, is it bad? Why? I'd love to see answers on this, because I have seen the figures used like a kudgel without specifying what the numbers actually refer to. It's frustrating as hell.
- jeffbee 1y ago
  The water is "used" in the sense that it evaporates. At a global average rate of 1 liter per kilowatt-hour of energy, Google claims.
  - aspenmayer 1y ago
    Does this evaporated water stay in the loop and condense out later? Is an extra liter on the front end needed in the line until the first liter falls out of the back end?
  - Lerc 1y ago
    What does that mean for environmental impact? Hydroelectric power uses water in the sense that the "used" water is at a lower altitude. What happens once that is done, is what matters. Depending on what global average means, it seems like that's quite a lot of cycling of evaporation unless they are releasing steam at 800C Looking up overall water usage, the US uses 27.4Billion gallons a day residential and 18.2 Billion gallons industrial. It surprised me that industrial was lower, but I guess the US manufactures less these days. If the 1kwh per litre were accurate then judging by this calc https://www.google.com/search?q=(27.4billion+gallons+*365)*+(1000+kwh+per+litre)+in+TWh https://www.google.com/search?q=(27.4billion+gallons+*365)*+... 37 857 903.3 terawatt hours 0.1% of The residential water use of the US would be enough to cool the entire Electicity output of the world (about 30,000TWh) (of course, with these things it's easy to slip an order of magnitude(or several) so best check my numbers)
sleepydog 1y ago
AWS had a similar article a couple months ago: https://www.aboutamazon.com/news/aws/aws-liquid-cooling-data-centers https://www.aboutamazon.com/news/aws/aws-liquid-cooling-data... In either case I cannot find out how they dump the heat from the output water before recycling it. That's a problem I find far more interesting.
esaym 1y ago
Yes see: https://www.austinchronicle.com/news/2025-07-25/texas-is-still-in-drought-and-ai-data-centers-are-quietly-guzzling-up-water/ https://www.austinchronicle.com/news/2025-07-25/texas-is-sti...

deleted 1y ago

[deleted]

bri3d 1y ago

The CDU is inside the datacenter and strictly liquid to liquid exchange. It transfers heat from the rack block's coolant to the facility coolant. The facility then provides outdoor heat exchange for the facility coolant, which is sometimes accomplished using open-loop evaporative cooling (spraying down the cooling towers). All datacenters have some form of facility cooling, whether there's a CDU and local water cooling or not, so it's not particularly relevant. The whole AI-water conversation is sort of tiring, since water just moves to more or less efficient parts or locations in the water cycle - I think a "total runtime energy consumption" metric would be much more useful if it were possible to accurately price in water-related externalities (ie - is a massive amount of energy spent moving water because a datacenter evaporates it? or is it no big deal?). And the whole thing really just shows how inefficient and inaccurately priced the market for water is, especially in the US where water rights, price, and the actual utility of water in a given location are often shockingly uncorrelated.

maartin0 1y ago
Slightly old but interesting https://blog.equinix.com/blog/2024/09/19/how-data-centers-use-water-and-how-were-working-to-use-water-responsibly/ https://blog.equinix.com/blog/2024/09/19/how-data-centers-us...
deleted 1y ago
[deleted]
bjackman 1y ago
Even without AI the whole water conservation topic is kinda silly. The margin at which it makes sense to save water varies wildly by location, but the cultural dominance of the western USA infiltrates everything. Here in Zürich, my office briefly installed water saving taps. This is a city of less than half a million where the government maintains 1,200 fountains that spew drinkable water 24/7. But someone at the California HQ said saving water is important and someone at the Swiss subsidiary said yes sir we'll look into it right away sir.
- acyou 1y ago
  It's on the same level as people using incandescent light bulbs. Well we clear 160k Euros after taxes and have public medical care, and electricity is 10c/kWh here, so why does it matter what bulbs we use? We live in an area surrounded by grass fed cows, so what does it matter if we throw away 3/4 of our steak? Without regard to how plentiful resources are in our particular area, being needlessly wasteful is in bad taste more than anything. It's a lack of appreciation of the value of what we have. For water specifically - it is generally speaking the most valuable resource available, we just don't appreciate it because we happen to have a lot of it.
  - MindSpunk 1y ago
    While I'm not saying waste when things are plentiful in general is okay, I think water is a unique case that can be treated differently. Comparing to energy costs isn't the same because using the energy for the incandescent bulb consumes that energy permanently. The gas/coal/fuel can't be un-burned. Although solar changes this as the marginal cost of that energy is free. Comparing to food is similar. Once the food is wasted it is gone. Water is typically not destroyed, it's just moved around in the water cycle. Water consumption in a region is dictated by the throughput the water cycle replenishes the reservoirs you're pulling from. "Waste" with water is highly geographic, and it's pretty reasonable to take exception to California projecting their problems to geographic regions that they aren't important.
    - fennecfoxy 1y ago
      It still takes energy, chemicals and therefore pollution to clean water once it's been turned into greywater.
      - ignaloidas 1y ago
        Sun is continuously running a very nice distillation cycle the size of the world that makes fairly clean water just fall out of the sky. It's only a question of where does it fall, and how much. If you want it even cleaner, wait a couple centuries for it to filter down underground, and get it from there - besides maybe a bit high mineral contents, that can easily be removed, it's essentially free, clean water. The only question is how much it's replenished in the area you're taking it from. There's plenty of areas where there's more rainfall, than there is outflow/evaporation, with water continuously replenishing deep groundwater. "Saving water" in such areas is of little concern besides the basic, economic one of well maintenance - each one can only pull so much, and more usage means more wells, and more upkeep.

jeffbee 1y ago

[flagged]

wredcoll 1y ago
I looked very hard but I don't see a way to subscribe to your newsletter?
stripe_away 1y ago
> there is a massive influence operation that seeks to destroy knowledge, science, and technology in the United States Agreed. Started with big tobacco by discrediting the connection to lung cancer, playbook copied by many and weaponized by Russia. > There is no subjective measure by which the water used by AI is even slightly concerning. Does not follow from your first point. The water has to be sourced from somewhere, and debates over water rights are as old as civilization. For one recent example, see i.e. https://www.texaspolicy.com/legewaterrights/ https://www.texaspolicy.com/legewaterrights/ You are probably correct that the AI does not damage the water, but unless there are guarantees that the water is rapidly returned "undamaged" to the source, there are many reasons to be concerned about who is sourcing water from where.
deleted 1y ago
[deleted]
deleted 1y ago
[deleted]
bryan_w 1y ago
Ayyo chill. Don't let on that you know their plans. People aren't ready to know about the operations yet, so you'll come across as off balanced
williamdclt 1y ago
It doesn't even pass the sniff test because the "AI wasting water" argument comes from liberals based on ecological concerns, whereas the systematic attack on knowledge/science comes from conservatives who explicitly do not give a crap about ecological concerns

Lerc 1y ago

I have encountered a lot of references to AI using water, but with scant details. Is it using water in the same way a car uses a road? The road remains largely unchanged? The implication is clear that it is a waste, but I feel like if they had the data so support that, it wouldn't be left for the reader to infer. I can see two models where you could say water is consumed. Either talking about drinkable water rendered undrinkable, or turning water into something else where it is not practically recaptured. Tuning it into steam, sequestering it in some sludge etc. Are these things happening? If it is happening, is it bad? Why? I'd love to see answers on this, because I have seen the figures used like a kudgel without specifying what the numbers actually refer to. It's frustrating as hell.

jeffbee 1y ago
The water is "used" in the sense that it evaporates. At a global average rate of 1 liter per kilowatt-hour of energy, Google claims.
- aspenmayer 1y ago
  Does this evaporated water stay in the loop and condense out later? Is an extra liter on the front end needed in the line until the first liter falls out of the back end?
- Lerc 1y ago
  What does that mean for environmental impact? Hydroelectric power uses water in the sense that the "used" water is at a lower altitude. What happens once that is done, is what matters. Depending on what global average means, it seems like that's quite a lot of cycling of evaporation unless they are releasing steam at 800C Looking up overall water usage, the US uses 27.4Billion gallons a day residential and 18.2 Billion gallons industrial. It surprised me that industrial was lower, but I guess the US manufactures less these days. If the 1kwh per litre were accurate then judging by this calc https://www.google.com/search?q=(27.4billion+gallons+*365)*+(1000+kwh+per+litre)+in+TWh https://www.google.com/search?q=(27.4billion+gallons+*365)*+... 37 857 903.3 terawatt hours 0.1% of The residential water use of the US would be enough to cool the entire Electicity output of the world (about 30,000TWh) (of course, with these things it's easy to slip an order of magnitude(or several) so best check my numbers)

sleepydog 1y ago

AWS had a similar article a couple months ago: https://www.aboutamazon.com/news/aws/aws-liquid-cooling-data-centers https://www.aboutamazon.com/news/aws/aws-liquid-cooling-data... In either case I cannot find out how they dump the heat from the output water before recycling it. That's a problem I find far more interesting.

esaym 1y ago

Yes see: https://www.austinchronicle.com/news/2025-07-25/texas-is-still-in-drought-and-ai-data-centers-are-quietly-guzzling-up-water/ https://www.austinchronicle.com/news/2025-07-25/texas-is-sti...