Lockheed Martin just announced plans to partner with the Reignwood Group to construct the world’s largest Ocean Thermal Energy Conversion (OTEC) plant off the coast of southern China. The OTEC process—which uses the temperature difference between the cold waters of the deep ocean and warm surface waters to generate electricity—is nothing new, but few facilities have ever been constructed. The floating pilot plant will generate 10MW of electricity – enough to power the Reignwood Group’s planned net-zero energy resort on the nearby mainland.
Unlike other renewable energy sources, such as solar or wind, OTEC plants can produce electricity around the clock in areas with warm, tropical climates (such areas might expand over the coming years). Gizmag explains that there are different cycle types of OTEC systems, “but the prototype plant is likely to be a closed-cycle system.”
“This sees warm surface seawater pumped through a heat exchanger to vaporize a fluid with a low boiling point, such as ammonia. This expanding vapor is used to drive a turbine to generate electricity with cold seawater then used to condense the vapor so it can be recycled through the system.”
This will be the first OTEC plant for Lockheed Martin, after a previous collaboration to construct a facility in Hawaii was shelved. And the technology is not cheap—the costs associated with creating an offshore platform that pumps cold water up from the depths of the ocean are significant, but Lockheed and their partner hope that the returns will outweigh those costs.
Over the coming decade Lockheed intends to develop additional commercial scale OTEC plant, ranging in size from 10MW to 100MW. The companies estimate that over the course of one year, a 100MW OTEC plant could generate electricity equivalent to 1.3 million barrels of oil, and reduce carbon emissions by half a million tons.
Construction on the prototype OTEC plant to set to begin next year.