A heat pump is used to heat a house in the winter and then reversed to cool the house in the summer. The inside temperature of the house is to be maintained at 20°C. The heat transfer through the house walls is 7.9 kJ/s and the outside temperature in winter is 5°C. What is the minimum power (approximate required to drive the heat pump)?
Option (A)
40.5 W
Option (B)
405 W
42.5 W
425 W
Correct Option:
Question Solution:
(COP)max = {T2/(T2-T1)}
= {293/(293-278)}
= 19.5339

(Refrigeration effect / Minimum power consumed) = [COP]
19.533 = 7.9 x 1000/Pmin
Minimum power = 404.43