Context

The principle of ocean thermal energy conversion is based on the use of the temperature difference between the surface and the depths of the ocean to operate a thermal machine. Production is optimal when the temperature difference becomes greater than 20°C, which is the case in tropical areas. The subsurface supply of bottom water of very different temperature and chemical composition, as well as the cooling of the surface water at the exchanger outlet, could locally induce a change in the functioning of the planktonic ecosystem equivalent to the implementation of artificial upwelling.

Objective

To study the potential impacts of deep-sea subsurface discharges from an ocean thermal energy conversion plant.

Scientific and technical contents

• Characterisation of the initial state in the Bellefontaine area (Martinique), before the operation of the OTEC pilot plant.
• Simulation of the coupled physical/biogeochemical and ecosystem dynamics during the operation phase of the OTEC plant.
• Characterisation (composition and productivity) of the planktonic community likely to appear in different mixing scenarios determined from the simulation previously carried out.
• Integration of data to validate the coupled physical biogeochemical model to assess the impact of the OEC on biological productivity, environmental conditions and material flows.
• Identification of physical and chemical factors playing a key role on the physiology of biogeochemically important species isolated from the environment.

Partners and funding

This project was led by Université de Bretagne Occidentale and France Energies Marines.

The total project budget was €604K.

This project received funding from France Energies Marines and its members and partners.

Photo credit: MJO / Pixabay