Give an estimate for the COP in the previous problem and the power needed to drive the heat pump when the outside temperature drops to −15◦C.

Data from previous problem

A house should be heated by a heat pump, β' = 2.2, and maintained at 20◦C at all times. It is estimated that it loses 0.8 kW for each degree that the ambient is lower than the inside. Assume an outside temperature of −10◦C and find the needed power to drive the heat pump.