@nprofile1q... Right now I have two independent heat pumps that go to outside air, not ground:
* Big Carrier/Bryant one, not sure of size, for the house connected to forced-air ducting to heat and cool the living spaces
* 18K BTU Mitsubishi mini-split for the lab
It rarely gets that cold here in the winter (often not even below 0C) so air heat pumps work decently well. The big efficiency loss comes from rejecting 4 kW of heat from the lab 24/7 to the outside in the winter, then pumping heat from the outside into the house to heat it. If I could pump that waste heat from the lab directly to the house it would save an unspecified but probably decently large amount of energy - right when the solar generation is at a minimum.
* Big Carrier/Bryant one, not sure of size, for the house connected to forced-air ducting to heat and cool the living spaces
* 18K BTU Mitsubishi mini-split for the lab
It rarely gets that cold here in the winter (often not even below 0C) so air heat pumps work decently well. The big efficiency loss comes from rejecting 4 kW of heat from the lab 24/7 to the outside in the winter, then pumping heat from the outside into the house to heat it. If I could pump that waste heat from the lab directly to the house it would save an unspecified but probably decently large amount of energy - right when the solar generation is at a minimum.
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