8. The water-cooled nuclear reactor is the most cost effective power plant 

 for the in-situ power system that operates at power levels greater than 30 kw. 



9. The diesel engine generator is the most cost effective power plant for both 

 the surface and shore-based power systems. 



10. AC power transmission is more cost effective for distances up to 10 miles 

 between power source and load module; distances from 10 to 500 miles 

 involve trade-offs; and beyond 500 miles, DC power transmission is more 

 cost effective. 



1 1. The most cost effective generated voltage is 480 volts, 3 phase, 60 Hertz 

 for loads of 30, 100, and 300 kw and 4,160 volts, 3 phase, 60 Hertz for loads 

 of 1,000 to 3,000 kw. 



12. An armored, polyethylene-insulated and jacketed, three-conductor cable 

 provides the most reliable transmission cable for all deep ocean power systems. 



13. A four-point mooring system is the most reliable method of mooring a 

 surface plant. 



RECOMMENDED DEVELOPMENT PROGRAMS 



As a consequence of the study program on underwater power systems, 

 several development or "high risk" areas were identified. These development 

 areas are necessary to complete the preliminary design of selected power 

 systems (see the Appendix). The establishment of a development program 

 for the "high risk" areas would greatly improve the cost effectiveness of the 

 selected systems. 



Cable Connectors 



The surface-tendered and the shore-based underwater power systems 

 require two different connectors for each system — one at the power plant 

 and one at the load module. For the in-situ power systems, two connectors 

 are also required, but both would be identical. 



Connectors can be characterized as two basic types, wet and dry. The 

 dry connector is essentially an electrical device that provides the necessary 

 continuity between a cable and a particular module. In a dry connector, 

 water or moisture are not allowed to enter the connection point. Therefore, 

 the connection must be made in a relatively dry atmosphere and, in the case 

 of underwater systems, connections must be made prior to emplacement of 

 the cable or modules. A wet connector has the same capabilities as the dry 



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