Publications

Survey of Energy Resources 2007

The Way Ahead and the Market

As with most new technologies, the financial sector is slow to involve itself until one or more representative demonstration plants have operated successfully - and this has proved to be true in the past for OTEC technology. However, with the progressive reduction in risks - for example the mooring of a floating OTEC plant will now be an application of 'routine' offshore oil and gas experience - a number of more enlightened financial bodies are now prepared to become involved at this relatively early stage of development. Other funding sources would include agencies such as the World Bank or European Development Bank and a further potential source of funding is possible through the Lomé and Cotonou Agreements between the European Union and the Africa-Caribbean-Pacific (ACP) States, many of which are prime candidates to use OTEC power.

In Europe both the European Commission and the industrially-based Maritime Industries Forum examined OTEC opportunities with relevance to DOWA in general rather than just OTEC, and the UK published its Foresight document for the marine sector, looking five to twenty years ahead, and both OTEC and DOWA were included in the energy section of the paper. It is significant that the emphasis in the recommendations from all three European groupings has, again, been on the funding and construction of a plant in the 5-10 MW range.

Current US activity is concentrating on an Indian Ocean island site, and it is perhaps noteworthy that both Japanese and British evaluations continue to identify Fijian prime sites, one each on the two largest islands of that country.

The worldwide market for all renewables has been estimated for the timescales from 1990 to 2020 and 2050, with three scenarios and, not surprisingly, all show significant growth. Within those total renewable figures, opportunities exist for the construction of a significant amount of OTEC capacity, even though OTEC may account for only a small percentage of total global electricity generating capacity for some years.  Estimates have been made by French, Japanese, British and American workers in the field, suggesting worldwide installed power for up to a thousand OTEC plants by the year 2010, of which 50% would be no larger than 10 MW, and less than 10% would be of 100 MW size. On longer timescales, the demand for OTEC in the Asia/Pacific region has been estimated at 20 GW in 2020 and 100 GW in 2050 (OECD, 1999). It has to be said that some of these numbers seem optimistic, with realisation depending on the successful operation of a number of demonstrator plants at an early date.

In summary, however, it can realistically be claimed that the economic commercialisation of OTEC/DOWA is 'now' - nearly all the technology is established, and the greatest concentration of effort seems logically to be aimed at lining up an increased range of suitable funding sources.
Don Lennard
Ocean Thermal Energy Conversion Systems Ltd,
United Kingdom