In extremely cold weather conditions where the inside thermostat is set to 27 C
ID: 2224051 • Letter: I
Question
In extremely cold weather conditions where the inside thermostat is set to 27 C and the outside temperature is -20 C, your 1200 square ft house might lose heat through the walls at a rate of 3500 W. For an air conditioner used as a heat pump, the coefficient of performance can be as high as the inverse of the Carnot efficiency which is run between the temperature inside (27 C) and the temperature outside (-20 C). How much would it cost to heat your house for one week using such a heat pump? (note that a real air conditionier usually has a COP which is half that for a Carnot cycle)Explanation / Answer
in one week:
energy lost = 4000 x 3600 x 24 x 7 = 2.41 x 109 J