b) On a winter day when the average outdoor temperature remains at about 4°C, the house isestimated to lose heat at a rate of 62,000 kJ/h. For this reason a Carnot heat pump is used toheat a house and maintain it at 23°C. If the heat pump consumes 6 kW of power whileoperating, determine (a) how long the hecat pump ran on that day: (b) the amount of heatremoved from surounding (Q.); and (c) the total heating costs, assuming an average price of6.5¢/kWh for electricity (d) the heating cost for the day if res istance heating is used insteadof a heat pump assuming an average price of 6.5¢/kWh for clectricity.

Heat pump: The device that is used for transfer heat is called a heat pump. Refrigerators and air…

b) On a winter day when the average outdoor temperature remains at about 4°C, the house is estimated to lose heat at a rate of 62,0000 kJ/h. For this reason a Carnot heat pump is used to heat a house and maintain it at 23°C. If the heat pump consumes 6 kW of power while operating, determine (a) how long the heat pump ran on that day: (b) the amount of heat removed from surrounding (Q.); and (c) the total heating costs, assuming an average price of 6.5¢/kWh for electric ity (d) the heating cost for the day if res istance heating is used instead of a heat pump assuming an average price of 6.5e/kWh for clectricity.

b) On a winter day when the average outdoor temperature remains at about 4°C, the house is estimated to lose heat at a rate of 62,0000 kJ/h. For this reason a Carnot heat pump is used to heat a house and maintain it at 23°C. If the heat pump consumes 6 kW of power while operating, determine (a) how long the heat pump ran on that day: (b) the amount of heat removed from surrounding (Q.); and (c) the total heating costs, assuming an average price of 6.5¢/kWh for electric ity (d) the heating cost for the day if res istance heating is used instead of a heat pump assuming an average price of 6.5e/kWh for clectricity.

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

See similar textbooks

Similar questions

The operating condition for the single compressor in a household refrigerator is the lowest box temperature, which is typically A. 0F B. -20F C. 20F D. 40F
Explain why a waterless, earth-coupled, closed-loop geo-thermal heat pump system is more efficient than a conventional closed-loop geothermal heat pump system.
Geothermal heat pumps, or water-source heat pumps, are classified as either _____loop or _____loop systems.
A thermal machine operates between 2 tanks at 800ºC and 20ºC; half of the power produced by this machine is used to drive a fully reversible heat pump that absorbs heat from the cold environment at 2ºC and transfers it to a house that is maintained at 22ºC. If the house loses heat at a rate of 62,000 kJ/hr, determine the minimum heat flux that must be supplied to the heat engine in kJ/hr. show step by step a) 11,565.3 kJ/hra. b) 8,406.8 KJ/hra c) 3,158.5 KJ/hra d) 6,110.9 KJ/hra d) N.A.
A heat pump is used to heat a house and maintain it at 24°C. On a winter day when the outdoor air temperature is –5°C, the house is estimated to lose heat at a rate of 80,000 kJ/h. Determine the minimum power required to operate this heat pump.
The drinking water needs of an office are met by cooling tap water in a refrigerated water fountain from 23 to 6°C at an average rate of 18 kg/h. If the COP of this refrigerator is 3.1, the required power input to this refrigerator is (a) 1100 W (b) 355 W (c) 195 W (d) 115 W (e) 35 W
Professor Modyn wants to power his refrigerator with a heat engine. A Carnot heat engine receives heat from a reservoir at 543.0 ∘C543.0 ∘C at a rate of 820 kJ/min820 kJ/min and rejects heat to the ambient air at 31.1 ∘C.31.1 ∘C. The entire work output of the heat engine is used to drive a refrigerator that removes heat from the refrigerated space at −3.23 ∘C−3.23 ∘C and transfers it to the same ambient air at 31.1 ∘C.31.1 ∘C. Note: The IUPAC sign conversion for work is used. Work into the system has a positive value. Determine the maximum rate of heat removal from the refrigerated space (kW) Determine the total rate of heat rejection to the ambient air. Heat rejection is a negative value. Account for both the heat engine and refrigerator.
A heat pump is to be used for heating a house in winter. The house is to be maintained at 78°F at all times. When the temperature outdoors drops to 25°F, the heat losses from the house are estimated to be 70,000 Btu/h. Determine the minimum power required to run this heat pump if heat is extracted from the outdoor air at 25°F.
A heat pump designer claims to have an air-source heat pump whose coefficient of performance is 1.8 when heating a building whose interior temperature is 300 K and when the atmospheric air surrounding the building is at 260 K. Is this claim valid?
A heat pump is absorbing heat from the cold outdoors at 5 degrees celsius and supplying heat to a house at 22 degrees celsius at a rate of 18,000kJ/h. If the power consumed by the heat pump is 2.5kW, the coefficient of performance of the heat pump is?
A heat engine working with a thermal efficiency of 35% receives 2 kW of heat from a furnace. The waste heat rejected from the engine is
a) A Carnot heat engine receives heat from a reservoir at 700 ° C at a rate of 600 kJ / min and rejects the waste heat to the ambient air at 25 ° C. The entire work output of the heat engine is used to drive a refrigerator that removes heat from the refrigerated space at - 6 ° C and transfers it to the same ambient air at 25 ° C. Determine (a) the maximum rate of heat removal from the refrigerated space and (b) the total rate of heat rejection to the ambient air.