Not every location has sufficient solar radiation (e.g. due to pervasive cloudiness) or wind energy (e.g. “Doldrums”) for these intermittent renewables. Some locations have geothermal energy resources, but other tropical coastal and island nations are not so fortunate. An alternative source of renewable energy is OTEC, taking advantage of the temperature differential between warm surface waters and cold deepwater. This technology was extensively engineered and pilot tested in the past, but recent technology improvements and cost reductions have made this solution worth considering again.
- For tropical islands without adequate renewable energy resources, the possibility exists to utilise the temperature differential from warm surface water (~25-30°C) to cold deepwater (~4-5°C @ 1000m) with Binary ORC turbine expander power generation technology;
- Onshore locations are possible (with steep nearshore bathymetry, middle illustration) – successful pilots have been done like this;
- Offshore locations are possible (with less steep bathymetry, right illustration) – using successful deepwater production technologies;
- Facilities sizes can range from 10 MW up to 100 MW – improved technologies of equipment (left illustration) and facilities combined
- with cost reductions have significantly improved the economic viability of this concept;
- Economic, environmentally sustainable persistent renewable OTEC energy.