Ocean Thermal Energy

Ocean Thermal Energy Conversion (OTEC) can be used to obtain energy from the temperature differences between layers in the ocean. Conditions are most favourable where there is a significant temperature difference between the surface layers of the ocean and deeper layers. A major advantage is that energy can be generated 24 hours a day. At present, this technology can only be used near the equator where the difference in temperature between the deeper layers and the surface is large enough. Deltares is supporting project developers, manufacturers, investors and government authorities during the process of designing, installing, managing and servicing OTEC plants. Developers are using our research to save costs and minimise the risks. In addition, governments and stakeholders can create support for OTEC plants using our impact assessments and location studies. Anyone involved in the development of OTEC plants can use our system knowledge to make their plant more sustainable and efficient.

source: Bluerise

Plume spread and water quality analyses

Using water to heat and cool OTEC systems changes the temperature of the water but the salt content remains unaltered. As a result, the density of the water changes. Discharging this water at a location with a different density creates a density flow, which can, in turn, result in potentially damaging algae growth at the inlet and outlet of the plant. Deltares maps the density flows, the plume spread and the impact of the hot-water discharges on water quality and ecology. In addition, Deltares can help developers with the hydraulic and thermal design of a plant. Analysing the heating and cooling process during intake and discharge makes it possible to optimise the design.

Due to the knowledge and experience we have acquired worldwide with conventional power plants, we can provide integrated assessments of OTEC projects and draw on expertise from multiple disciplines. But Deltares can also conduct smaller studies of specific problems. We were involved in the Bluerise OTEC Center on Curacao by assessing the potential of different locations. We supply research and consultancy for:

•           the optimisation of energy production;

•           the reduction of negative effects on the locality;

•           environmental impact studies;

•           operational management.


To optimise the design and yield of OTEC, and to predict the effects, we supply the following software packages:

•           Delft3D for re-circulation measurements, water-quality models and studies of salinisation.

•           CORMIX for measuring plume spreads around the discharge channel. CORMIX and Delft3D can also be used in combination.

•           WANDA for the hydraulic and thermal design of the input and discharge systems in an OTEC plant.