Heat Pumps

Heat pumps use the vapor-phase compression cycle to move thermal energy from a cold place to a hot place, in the opposite flow of nature. These are usually powered by electricity

SEER

The efficacy of the movement of heat to the consumption of electricity for cooling is quantified by the Seasonal Energy Efficiency Ratio (SEER).

$SEER = \frac{\textrm{BTU cooling provided}}{\textrm{Watt-hours of electricity expended}}$

HSPF

The ratio of electricity required to the heat moved is given by the Heating Seasonal Performance Factor (HSPF).

$HSPF = \frac{\textrm{BTU heating provided}}{\textrm{Watt-hours of electricity expended}}$