It sounds a little complex in a desert because (AFAIK) data centers produce relatively low-level heat, and in the summer the inlet side would need to be cooled significantly. This sounds like less of an issue in Norway with relatively low average temperatures.

The medium would be cheap as heck though.

Another confounding factor is the necessity of water cooling. I think data centers like evaporators because they can use dirt cheap and standard air cooled servers, and simply A/C the room with the evaporators, where more complex systems would need larger air heat exchangers and a well below ambient return.