On-Shore Siting of OTEC Plants

An overview is presented of the foremost parameters to be quantified when reviewing the site potential of tropical islands for land-based OTEC power generation. The part that aquaculture can play in boosting the payback on an OTEC station is discussed, drawing-on detailed analysis made for the EUROCEAN OTEC project (Ref. 1) at Curacao, and on recent reports for sites in the Indian Ocean (Ref, 2 and 3). Relative to the more publicized research on the cold water Intake pipe, turbines and heat exchanger systems, the specification of the mariculture facility has tended to be overshadowed as a design problem, and at times overlooked. Site suitability requirements for aquaculture need to be defined well In advance, even in those cases where start-up will be delayed until a large cold water flow is on-stream from the OTEC plant. The exploitation of the temperature difference between warm, surface waters (0 - 40m depth; annual range 27 - 30°C) and cold, underlying deepwater present in most tropical oceans (20°S - 20°N) was first put forward as early as 1881. TAYLOR (Ref. 4) has tabulated a list of countries best suited to OTEC plants: remotely situated, high transportation cost of imported oil and other fuels arid with year-round lack of freshwater Inhabited by an Indiginous community lying within 30 km of a stable, thermal resource of sufficient gradient (T18-23°C) to justify thermodynamic conversion into electric power at an overall efficiency of 1 - 2.5%