Ocean Thermal Energy Conversion: Power for the future?

Ocean Power Magazine explains
the vast amounts of power that can be created by using differences in temperatures in ocean layers of water. Puerto Rico is a prime area for this.

As long as the temperature between the warm surface water and the cold deep water differs by about 20°C (36°F), an OTEC system can produce a significant amount of power. The oceans are thus a vast renewable resource, with the potential to help us produce billions of watts of electric power.