> Air source heat pumps are insanely more efficient
Citation needed?
Efficient how? I'm sure a heat pump designed for a narrow range of input temperatures AND working with water which can transport a lot more heat should easily be more efficient.
https://www.energysage.com/heat-pumps/compare-air-source-geo... Seems to disagree
I assuming he means insanely more efficient than they used to be, not more efficient than ground-source (awkward wording though). I suppose they can also be described as more efficient in installation time, cost and equipment than ground source, but clearly not in operating efficiency.