Chilled ground water at 0degreeF is used to supply energy to

Chilled ground water at 0degreeF is used to supply energy to a heat pump that discharges heat to a house at a rate of 8000 kJ/hr. Over a month (50 days), the house\'s electric meter records 340 kW-hr of electricity sent to the heat pump. If we assume these are the only transfers of energy involved: What is the instantaneous rate of energy that the heat pump receives in [kW] and over one month in [k J] What is the Coefficient of Performance of the heat pump\' \'Show all calculations and unit conversions otherwise no points will be given.

Solution

The electricity received in one month period = 340 x 3600 KJ = 1224000 KJ

So instantenous rate of energy received by heat pump =1224000/24x30x3600 =0.472 KJ/s=0.472 KW

So total energy recived in one month = 1224000 KJ

The electricity discharged to house by heat pump = 8000 x 30 x 24 = 5760000 KJ

So Coefficient of Performance of heat pump = 5760000 / 1224000 = 4.71

It means that heat pump discharge the heat which is 4.71 times of the input electrical energy provided.