> However, that doesn't solve the problem of what to do with the heat once you have it.
Unfortunately they are not usually in great locations for this since you need other buildings, but if you have an ambient temperature district heating and cooling system for buildings nearby (sometimes called a 5th gen DHC system [1] - mainly characterized by the notion of prosumers ie producer/consumers of heat connected to a single loop system, rather than a more traditional supply loop/return loop topology) then datacenters can very easily fit in to the mesh as producers. Temps are typically 10-20c for ambient loops. The main insight is that that operating range is one that can be used quite well for both extracting heat and dumping heat simultaneously at different locations in the network.
You can also of course just add the heat directly to a hot water supply loop, eg [2]
Unfortunately they are not usually in great locations for this since you need other buildings, but if you have an ambient temperature district heating and cooling system for buildings nearby (sometimes called a 5th gen DHC system [1] - mainly characterized by the notion of prosumers ie producer/consumers of heat connected to a single loop system, rather than a more traditional supply loop/return loop topology) then datacenters can very easily fit in to the mesh as producers. Temps are typically 10-20c for ambient loops. The main insight is that that operating range is one that can be used quite well for both extracting heat and dumping heat simultaneously at different locations in the network.
You can also of course just add the heat directly to a hot water supply loop, eg [2]
[1] https://en.m.wikipedia.org/wiki/District_heating (see the section in history on 5th gen)
[2] https://www.nrel.gov/computational-science/waste-heat-energy...
https://www.nrel.gov/docs/fy19osti/73644.pdf