A heat pump maintains a dwelling at a temperature Tin when the outside temperature Tout is 5oC. The heat transfer heat through the walls and roof is UA = 2000 kJ/hr oC. Q = UA(Tin-Tout).
Find: a) The minimum cost to operate the heat pump for a day when the inside temperature is 20oC. b) Plot the minimum cost to operate the heat pump for a range of inside temperatures of 18 to 23oC.
Assume: Electricity costs $0.08 per kWhr.