Rematog,
Based on 2 yrs of building ~8 to 10 automotive A/C evaporators per minute, I think you’re underestimating the cost savings of mass production. The important part of the equation to me is not just removing excess heat from the FF device, but rather heating water to use in home heating, and further recycling the thermal energy by using the losses from the pipes to heat air as well.
The plant I worked in was probably too isolated for this to be effective, but installing a FF device in a large office and/or apartment building would give us a huge existing heat sink that would further reduce the building’s energy costs.
