Chapter 21, Problem 43EAP

There has long been an interest in using the vast quantities of

thermal energy in the oceans to run heat engines. A heat engine

needs a temperature difference. a hot side and a cold side. Conve-

niently, the ocean surface waters are warmer than the deep ocean

waters. Suppose you build a floating power plant in the tropics

where the surface water temperature is 30°C. This would be

the hot reservoir of the engine. For the cold reservoir, water would

be pumped up from the ocean bottom where it is always 5°C.

What is the maximum possible efficiency of such a power plant?