Current measurements for the ocean thermal energy conversion program

The Ocean Thermal Energy Conversion (OTEC) Program of the Department of Energy is directed toward obtaining electrical power from a heat engine driven by the temperature differential between warm surface and colder subsurface waters. Preliminary design concepts envision a large surface plant, moored and/or actively propelled, attached to a long (order of 100 m´s) cold water pipe. Water is pumped into the plant at the surface and bottom of the pipe, and discharged at some mid-depth. The designer of an OTEC plant must consider currents in order to minimize the effect of the plant on the environment and the effect of the environment on the plant. For instance, current data are required to evaluate the effect of the plant effluent on the environment. Also, the dynamic loading on the plant caused by ambient currents must be computed to design a suitable mooring or propulsion system. Current data are necessary to design a cold water pipe which will neither collapse nor bend. The observational programs developed for obtaining current velocity data at potential OTEC sites are presented.