A heat pump cycle operating at steady state receives energy by heat transfer fro
ID: 1591308 • Letter: A
Question
A heat pump cycle operating at steady state receives energy by heat transfer from well water at 10 degree C and discharges energy by heat transfer to a building at the rate of 1.2 Times 10^5 kJ/h. Over a period of 14 days, an electric meter records that 1490 kW h of electricity is provided to the heat pump. These are the only energy transfers involved. Determine the amount of energy that the heat pump receives over the 14-day period from the well water by heat transfer, in kJ, and the heat pump's coefficient of performance.Explanation / Answer
a) heat recived by heat pump, Q1 = 1.2*10^5*(14*24*60*60)
= 1.524*10^8 J
b) electrical energy provided by the heat pump, Workdone = 1490 kWh
= 1490*3.6*10^6
= 5.364*10^9 J
so, COP = Workdone/Q1
= 5.364*10^9/(1.524*10^8)
= 35.2