The Ocean Thermal Electric Conversion system (OTEC) is an example of a high-tech electric generator. It takes advantage of the fact that in the tropics, deep ocean water is at a temperature of 4 C, while the surface is at a temperature around 25 C. The idea is to find a material that boils between these temperatures. The material in the fluid form is brought up through a large pipe from the depths, and the expansion associated with its boiling is used to drive an electrical turbine.
The gas is then pumped back to the depths,where is condenses back into a liquid and the whole process repeats.
What is the maximum efficiency with which OTEC can produce electricity?
1. 1.3%
2. 7.6%
3. 84%
4. 7.0%
5. 93%
