Waste heat could drive a turbine.
I don't see why the waste heat couldn't drive a small turbine and generate some power.
I was thinking that the attic heat, and/or AC heat could heat water or ammonia. Let it run through a buried pipe under the ground, where it cools. We could get a cycle going and drive the turbine.
Throw some Solar Cells on the roof and maybe a wind turbine in the back yard and watch those energy bills drop.