Would it be possible to use a Thermoelectric Generator, similar to what is used in space probes but instead on the cooling system of mining rigs, in order to produce electricity to reduce the cost of electricity? How effective would this be and would it have a significant impact on the electric bill?
What is setup cost? Most forms of generating energy have a high initial cost.
The initial cost makes it hard if not impossible to compete against those using cheap electricity. Normally they just don't make sense as an investment.