A heat pump keeps the air temperature in a house at a temperature of 22.5 oC. The house is losing heat to the outside air through the walls and the windows at a rate of 61,500 kJ/h while the energy generated within the house from people, lights, and appliances amounts to 4,500 kJ/h. For a COP of 2.5, determine the power input to the heat pump in kW.