Electrochemical antifouling technology for replacement of heavy metal and organic biocides in marine hydrokinetic energy generation

Marine hydrokinetic (MHK) technologies attempt to recover the abundant energy source in the world´s oceans and the advancement of these technologies forms the core of the activities of the Northwest National Marine Renewable Energy Center (NNMREC - a Department of Energy sponsored partnership between Oregon State University and the University of Washington). MHK devices in the ocean environment can experience functional problems due to the attachment and growth of living organisms on manmade surfaces, usually termed biofouling, and thus an important thrust of NNMREC´s activities focuses on long term solutions for this problem. In conventional hulls, prevention and mitigation of the effects of biofouling is effected through the use of biocidal coatings, though usually with short maintenance cycles in the order of 5 years. Long term solutions for biofouling prevention with decreasing maintenance requirements need to be developed and tested for reliability. This paper presents the antifouling work on electrochemically protected surfaces and results on the accelerated aging of this technology for periods on the order of 20 years.