Ocean thermal energy conversion heat exchanger biofouling - strategies of control

One of the critical technological problems identified for Ocean Thermal Energy Conversion (OTEC) is biofouling of the heat exchanger. The OTEC heat exchanger operates on a low temperature differential, and overall heat transfer is quite sensitive to the thermal resistivity resulting from seawater-side biofouling. A biofouling control system(s) will be an integral part of the OTEC plant, and efforts to identify appropriate biofouling countermeasures have begun. A number of methods for controlling biofouling are known, but data to evaluate the adequacy of these countermeasures for this application are not available. This paper deals with the effect of biofouling on OTEC plant efficiency. A brief review of some of the candidate biofouling control systems, as well as factors considered in evaluating their suitability for OTEC is presented. Areas of research that must now be addressed are identified.