Technical University Munich has been doing this since at least 2011 to heat half of their campus: https://www.lrz.de/services/compute/supermuc/systemdescription

Technical University Munich has been doing this since at least 2011 to heat half of their campus: https://www.lrz.de/services/compute/supermuc/systemdescription/ https://www.lrz.de/services/compute/supermuc/systemdescripti... (see section on warm water cooling)