Consider an electrically heated house whose walls are 3 m high with a thickness to thermal conductivity ratio of L / k = 2.3 m^2 ° C / W. Two walls of the house are 12 m long, and the other two are 9 m long. The house is kept at 25 ° C at all time, while the outside temperature varies. Determine the amount of heat lost through the walls of the house on a given day when the average temperature of the outside air is 7 ° C. In addition, determine the cost of this heat loss considering that the unit cost of electricity is US $ 0.075 / kWh. It is known that hi = 8.29 W / m^2 ° C for the internal surface of the walls and ho = 34 W / m2 ° C for the external surface of the wall

Consider an electrically heated house whose walls are 3 m high with a thickness to thermal conductivity ratio of L / k = 2.3 m^2 ° C / W. Two walls of the house are 12 m long, and the other two are 9 m long. The house is kept at 25 ° C at all time, while the outside temperature varies. Determine the amount of heat lost through the walls of the house on a given day when the average temperature of the outside air is 7 ° C. In addition, determine the cost of this heat loss considering that the unit cost of electricity is US $ 0.075 / kWh. It is known that hi = 8.29 W / m^2 ° C for the internal surface of the walls and ho = 34 W / m2 ° C for the external surface of the wall