There are currently no OTEC plants operating commercially. However, there have been and continue to be experimental operations
and research done on this alternative energy source.
OTEC in Hawaii
OTEC technology, cold seawater used at the
Natural Energy Laboratory of Hawaii Authority (NELHA) to
air condition (cool) administration and laboratory buildings. Fifty tons of air conditioning are provided, saving NELHA
approximatley $4000 per month in electricity costs. The system needs substantially less maintenance than
the other, more traditional,compressor airconditioner systems.
The first successful at-sea, closed-cycle OTEC operation was on board the
Mini-OTEC, a converted Navy barge working within the waters off Keahole Point. Operating for three months, from August-October
1979, Mini-OTEC generated around 50 kilowatts of gross power. The net power ranged from approximatley 10-17
kilowatts. The turbine generator allowed Mini-OTEC to produce a gross output of up to 55 kW. Because various
processes must be performed on the ship to produce energy and transfer it, the net power output was around 15
OTEC-1, also once a Navy tanker, tested within the
confines of the waters off Kawaihae on the Kona Coast, heat exchangers and other components of a closed-cycle OTEC plant. Investigations
of the environmental effects of an ocean-stationed OTEC plant were studied. OTEC-1 was designed predominantly for
research purposes rather than electricity production. This operation was founded by the US Department of Energ (USDOE).
The Future of OTEC
Operations such as the ones mentioned above continue to be studied and
researched, as scientists must learn more about OTEC before it can be made for commercial use. The expenses of OTEC, including
the transport of the energy or fresh water it produces, as well as the building and securing of OTEC sites, stop it from becoming
a likely alternative in the near future. Still, through further research, it is very possible that mankind may be looking
at a greener earth, whether it be decades, centuries, or millennia from now; one which is powered by the sun and the ocean.