This was the promise originally but it turned out to be impossible. As it turns out, data center waste water is nowhere near warm enough to use for heating.
It would work if you would put the server directly into the greenhouses, 25°C is cool enough for servers and warm enough for plants. But the expense of having moisture, bug and dirt resistant servers and technicians would far outweigh the energy efficiency.
Hahaha - never thought of it that way. Given how dirt free a lot of modern greenhouse agriculture is, it could conceivably be done.
if that works, why doesn't it work to put them next to each other and pump the warm air from the server into the greenhouse? would that already have to much loss?