| dc.description.abstract | Of the known sources of ocean energy, salinity gradients have the most potential. These gradients are found naturally in estuarine environments, but can be artificially produced, given a salt source, such as a hypersaline lake or salt dome. The heterosaline vapor pump is the most promising of the proposed methods of utilizing this energy, as it eliminate the need for the expensive membranes common to the other methods. The vapor pump operates on the difference in vapor pressures between salt and fresh waters. This difference is the driving force of the pump, and varies with both salinity gradient and temperature. It serves to define the maximum efficiency of the pump
E=(P_O-p^')/P_O
where (Pₒ) is the vapor pressure of the fresh or hypotonic solution, and (p') is the depressed vapor pressure of the salt or hypertonic solution. Experimental results indicate that efficiency is independent of temperature, but increases with an increased salinity gradient. Higher efficiencies are obtained by using two salt solutions, rather than freshwater and a salt solution to construct a given gradient | en |
