A house loses heat through its exterior at a rate of 5 kW when the inside temperature is 22◦C and the outside temperature is −5◦C. Determine the electrical power required to maintain the interior temperature at 22◦C for the following two cases: (a) The electrical power is used in resistance heaters that convert all the power to heat. (b) The electrical power is used to drive the motor of a heat pump that has a coefficient of performance equal to 30% of the Carnot cycle value.

A house loses heat through its exterior at a rate of 5 kW when the inside temperature is 22◦C and the outside temperature is −5◦C. Determine the electrical power required to maintain the interior temperature at 22◦C for the following two cases: (a) The electrical power is used in resistance heaters that convert all the power to heat. (b) The electrical power is used to drive the motor of a heat pump that has a coefficient of performance equal to 30% of the Carnot cycle value.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.46P

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