Summary 



Fouling control by mechanical cleaning of the OTEC plant does not 

 appear to be a severe problem. The critical area that needs attention is 

 the warm water inlet. A systematic underwater mechanical cleaning program 

 is feasible if the methods described above are applied. 



The OTEC design should incorporate features which permit easy access 

 by divers to confined areas (inlets and outlets), provide a hydraulic 

 station for underwater connections, and erect suitable grips and guides 

 on internal ducting to simplify diver cleaning operation. Hinged and 

 floating intake screen systems would permit easy access to both sides 

 of the screen. The engineering development of a tethered submersible 

 vehicle equipped with inspection and cleaning devices should be considered. 



Electrolytic generation of chlorine in critical areas such as intake 

 screens might be examined as a possible visible alternative. However, the 

 environmental aspects of such usage would have to be examined. 



EXECUTIVE SUMMARY 



DETERIORATION AND CORROSION CONTROL 



State of the art for deterioration and corrosion control in the 

 marine environment is advanced. The use of reinforced concrete as a 

 structural material for extended seawater immersion is well accepted pro- 

 vided certain basic guidelines are followed. The long-term preservation 

 of steel members through the combined use of anticorrosion coatings and 

 cathodic protection has been demonstrated. Materials such as titanium 

 are inherently corrosion-resistant while others, such as aluminum, require 

 extra precautions and efforts to maintain their integrity. I'Thile problems 

 relating to OTEC are largely attributable to the design and maintenance of 

 a very large structure, additional difficulties related to infrequent over- 

 haul of the main structure may also arise. 



FOULING CONTROL 



Active antifouling protection may be limited to 600 ft because evi- 

 dence indicates most fouling accumulation occurs in the photic zone. 



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