Thanks Roger, high capital cost is a problem. One of the main drivers is the cold water pipe, which moves the large masses of water. Paul Curto, former Chief Technologist with NASA, points out that with the heat pipe design the Carnot efficiency approaches 85% vs. about 70% with a cold water pipe. And the parasitic losses could be reduced as much as 50% and the complexity, mass (and cost) of the system reduced by at least 30%.
"The vast reduction in operating costs and environmental impacts would be worth investigation alone."
As to the offshore problem, Mid East oil is transported large distances, as would the hydrogen, ammonia or methanol energy carriers that could be produce to get OTEC power to market. Further Asia is one of the greatest developing energy markets and OTEC power produced in the western Pacific, is the closest source of power to that market.
I and my partners would be happy for the moment just to be able to demonstrate the potential of our unconventional design and prove its cost savings.
Ultimately it will take thousands of large OTEC plants but the objective is to get them below a billion a piece or get that much more output from the billion. Designs are on the drawing board for 1 gigawatt plants. Juxtapose to this is the potential for $60 trillion in environmental damage that none of the options Shalk is considering will do much to avert.