Date of Award


Document Type

Restricted Thesis

Terms of Use

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Degree Name

Bachelor of Arts


Engineering Department

First Advisor

Sophia Plata


In many locations in the United States, thermoelectric power plants are facing increasing regulatory pressure to decrease water withdrawals. An important part of this process is evaporation ponds, which may be made more cost effective by increasing evaporation rates. Previous research has suggested that photothermal umbrellas may be able to accomplish this by heating the surface of the water more efficiently. The previous research also found a limiting factor in the form of vapor transport, which my designs attempted to alleviate. My project found that, while it is possible to perforate the material and still have it perform better at heating water than without any coverage, the unique benefit of heating primarily the surface disappears when vapor transport is allowed. This result was confirmed via a test in which I put holes in the umbrella but did not permit vapor transport. In this test the surface temperature was once again higher than the bulk temperature. These findings indicate that the limiting factor of vapor transport will be difficult to avoid with this material and that it may be less than ideal for the purpose of thermoelectric power plant evaporation ponds.