I believe I've heard that heat pumps are good all the way down to -30 or so, though the efficiency at that point is pretty bad. That said, geological heat pumps can circumvent that as long as the ground doesn't freeze too deep where you live. Dig far enough and heat pumps work anywhere that's not permafrost, and I'm talking about 20-30 meters deep, not something insane like tapping underground magma.
I thought ones that shallow are only good if the ground doesn't freeze much? I know there are horizontal ones about that deep or so, and vertical ones that are designed for places where the ground freezes, or if you have little space for a horizontal installation.
The ground does not freeze that deep until you get to very northern latitudes but yea you do need the space for horizontal loops which not everyone is going to have.
I believe I've heard that heat pumps are good all the way down to -30 or so, though the efficiency at that point is pretty bad. That said, geological heat pumps can circumvent that as long as the ground doesn't freeze too deep where you live. Dig far enough and heat pumps work anywhere that's not permafrost, and I'm talking about 20-30 meters deep, not something insane like tapping underground magma.
Ground loops just have to be a bit under the frost line, more like 3 meters deep than 30
I thought ones that shallow are only good if the ground doesn't freeze much? I know there are horizontal ones about that deep or so, and vertical ones that are designed for places where the ground freezes, or if you have little space for a horizontal installation.
The ground does not freeze that deep until you get to very northern latitudes but yea you do need the space for horizontal loops which not everyone is going to have.