Photo: Renewable energy distribution across the Caribbean Community (CARICOM) nations.

With an abundance of solar and wind resources in their favour and the added benefit of lowered greenhouse gas emissions, many Caribbean island states are pursuing aggressive renewable energy integration in their national energy mix. In a recently published paper in Energies, Dr. Randy Koon Koon (Dept. of Physics) and co-authors from Germany, USA and UK, suggest that the ocean may provide another abundant and available renewable energy source which can help the region even achieve a 100% renewable target in the near future.

In the Caribbean, the renewable sources currently being relied on are still highly variable i.e. dependent on when there is (for example) sunshine or wind. Complementary technologies (e.g. batteries to store the energy when available) are therefore necessary to ensure grid stability and energy reliability. In their study entitled "Ocean Thermal Energy Conversion—Flexible Enabling Technology for Variable Renewable Energy Integration in the Caribbean" the authors show that ocean thermal energy conversion (OTEC), even if still too costly to be used on its own, may be a viable option for some Caribbean countries as a dispatchable electricity source to complement the variable renewable energy sources. OTEC takes advantage of the temperature difference between warm surface ocean water and cooler deep ocean water to drive a thermodynamic engine cycle. For low latitude regions like the Caribbean it represents a theoretically inexhaustible energy source. The researchers map islands which have the potential for deploying OTEC and use modelling techniques to show that an OTEC system with a capacity of several MW may be useful for islands with peak demand of a few tens of MW by significantly reducing the battery storage capacity needed to satisfy hourly demand throughout the year. They further note that in addition to suring up variable energy resources, OTEC can provide additional services beyond electricity generation, including desalination of seawater, cooling of buildings, and aquaculture. All these, they suggest, would help offset the costs associated with installing OTEC systems.

To read the paper: Brecha, R. J., Schoenenberger, K.; Ashtine, M.; Koon Koon, R. Ocean Thermal Energy Conversion—Flexible Enabling Technology for Variable Renewable Energy Integration in the Caribbean. Energies 2021, 14, 2192. https://doi.org/10.3390/en14082192    

To learn more about renewable energy research in the Department of Physics: https://www.mona.uwi.edu/physics/research-groups