My thermodynamics is rusty, but if they could concentrate it, that would mean that it's part of the "free energy" that could be used to power the data center it

My thermodynamics is rusty, but if they could concentrate it, that would mean that it's part of the "free energy" that could be used to power the data center itself, and given that it's impossible in practice to have perfect efficiency, there will always be excess heat that cannot be concentrated (entropy going up).