The process of moving heat from your house outside also creates excess heat, because no AC system is completely efficient (and it can't be because of the second law of thermodynamics).
Yes, but it still generates some heat. 300% means the ratio of the heat energy transfered to the energy consumed is 3. Perfect efficiency would be infinite COP.
> Heat pumps convert energy to heat more efficiently than combustion-based systems, potentially delivering 300-400% efficiency compared to the 80-98% efficiency of the best furnaces and boilers.
> This fundamental advantage stems from the fact that heat pumps move heat rather than generate it through combustion or resistance.
