Is there any reason the water can’t be safely consumed later? It’s not toxic or nuclear is it? The cooling water didn’t just up and disappear did it?
Edit: Links provided in the comments…
- https://arxiv.org/pdf/2304.03271
- https://www.youtube.com/watch?v=H_c6MWk7PQc
- https://www.youtube.com/watch?v=H_c6MWk7PQc&t=1264
- https://pivot-to-ai.com/2026/03/06/how-much-water-do-the-data-centres-use-its-a-secret/
- https://ui.adsabs.harvard.edu/abs/2025EcInd.17012986J/abstract
- https://en.wikipedia.org/wiki/List_of_tallest_cooling_towers
- https://en.wikipedia.org/wiki/Niederaussem_Power_Station
Notable comments:
- https://lemmy.world/comment/23672269
- https://sh.itjust.works/comment/25288634
- https://lemmy.cafe/comment/16350045
- https://sh.itjust.works/comment/25294655
Edit addendum: I’d like to thank everyone that’s participated in this question thread, sorry if I missed any good relevant links in the comments.
To be clear, I still loathe the whole AI datacenter era, it really is heavily wasteful of resources, notably energy, but I wanted to better understand the water usage situation.
I think you’re describing district heating, which works great in places that planned ahead and buried the necessary plumbing so that the waste heat from nearby industrial processes can be beneficially used to heat nearby homes and offices.
The detail, however, is that those industrial processes are diverting the heat to the district plumbing, but if nobody needs heating (eg 40 C summer weather), then they will vent the heat using air cooling to the atmosphere. That is to say, the demand for heating will vary at times, and this is fine because the industrial process can just go back to dumping the heat into the air.
This doesn’t work for AI data centers because the amount of “waste” heat (eg 100+ megawatts) is well in excess of any nearby demand for heating. To quantify demand, I looked to the district heating system of Ulaanbaatar, the capital city of Mongolia, home to 1.67 million people, and the coldest capital city in the world by average annual temperature:
The system serves 60% of the population, so about 1 million people. Where in the mostly-temperate USA could a 4 gigawatt AI data center be located so that it’s right next to 1 million people that need 24/7 heating as though they lived in Mongolia?
Scaling down to a 100 megawatt data center, the demand would be for a population of 25,000 living in essentially arctic conditions. Such places already have district heating, such as in Alaska. So if a smaller AI data center shows up, it just means the existing non-AJ heat source would fall back to dumping heat into the air.
In the end, there are very few places that need heating all year round, but AI datacenters would be producing heat all year round. Even if the heat were used for something outlandish, like heating every square meter of public roadway, that still might not be enough demand to quench these behemoth AI datacenters. And that’s before the cost of building out the district heating system.
We should definitely build district heating systems where they make sense, but building them so AI data centers can exist would be doing the right thing for the most terrible of reasons