[icefo]

I had the chance to visit the new datacenter of my college and on the server exhaust side there is a radiator as tall as the rack with cold water in it. All the pipes are under the floor.

IIRC they mainly put power hungry compute nodes for the clusters in this new datacenter and I remember that servers full of GPUs had crazy power draw. The water then goes through an heat exchanger to help generate hot water to heat the campus and for the taps.