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© Naval Energies

Constant renewable energy

Ocean Thermal Energy Conversion (OTEC) can be a game changing technology in tropical areas, including a number of EU overseas territories such as Martinique, La Reunion and Bonaire, where the cost of energy is particularly high. Given the right environment, OTEC can generate energy 24/7.

OTEC presents a considerable opportunity: a French government study estimates a global potential of 150GW – and the EIA is even more ambitious. Today, European technology developers are well positioned to capture a considerable share of this market.

Image courtesy of Makai Engineering -

How does it work?

Ocean Thermal Energy Conversion (OTEC) exploits the difference between cold and warm water to produce energy. OTEC plants use deep cold seawater and warmer surface seawater to produce a steady power supply. Technologies target around a 20°C or more temperature differential between cold and warm water.

OTEC prototypes are often land based, but floating prototypes are also under development, which can move from place to place.

OTEC can also produce a number of by-products, including fresh water, always in great need in tropical areas.

© Naval Energies

Progress to date

France’s Naval Group has installed an onshore OTEC prototype in French oversea territory La Réunion. Progress is also being made in Hawaii (US) and Japan.

In 2014, the European Commission’s NER300 programme awarded €73m to the Nemo project to develop a floating offshore prototype in Martinique. The 10MW project is scheduled for completion by 2020 and will provide electricity to 35,000 households.