Consider the wintertime heating of a house with a furnace compared to addition of Carnot heat engines/pumps.
Question:
Consider the wintertime heating of a house with a furnace compared to addition of Carnot heat engines/pumps. To compensate for heat losses to the surroundings, the house is maintained at a constant temperature Thouse by a constant rate of heat transfer, Q̇house. The furnace operates at a constant temperature TF, and with direct heat transfer, the heat required from the furnace, Q̇F is equal to Q̇house.
(a) Instead of direct heat transfer, if we utilize the surroundings, at TS, as an additional heat source and include heat pump technology, Q̇F may be reduced by generating work from a heat engine operating between TF and TS, then applying that work energy to a heat pump operating between TS and Thouse. Given that TF = 800 K, T = 293 K, TS = 265 K, and Q̇house = 40 kJ/h, determine Q̇F utilizing heat pump technology. No other sources of energy may be used.
(b) Another option is to run a heat engine between TF and Thouse and the heat pump between TS and Thouse. Compare this method with part (a).
Step by Step Answer:
Introductory Chemical Engineering Thermodynamics
ISBN: 9780136068549
2nd Edition
Authors: J. Elliott, Carl Lira