Hy

Also we have EE = IE

giving 0h = [ Wnet +( °L)]. Solving for (—Waet ) and substituting into the effi-

ciency equation, the result becomes jj =

0l 0

. Using the equi-

H y valence equation, the efficiency of a Carnot engine reduces to jj =

Hy v

For a refrigerator, the net effect is the cooling that we get, (QL), from a cold reservoir at (7L). The work required to pump this energy is (Wnet), and the energy given off to the environment at a temperature (TH) is (-QH). Therefore, the performance parameter, coefficient of performance for a refrigerator becomes f m \

V net

v h 1l y for a Carnot refrigerator.

For a heat pump, the net effect is the heating that we get, (-Qh) into a reservoir at a temperature of (TH). The work required to pump this energy is (Wnet), and the energy that is taken out of the environment at a temperature (TL) is (QL). Therefore, the coefficient of performance for a heat pump becomes f m \

Qh which reduces to y=

Carnot heat pump. It is also easy to prove that [y = (1 + ^)}using the results obtained above.

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Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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