By Daniel Cusick and ClimateWire, Source: Scientific American

Forty years of research and development by Lockheed Martin into harnessing energy from steep differentials in ocean temperatures will see its first commercial deployment in China. There, a resort developer has partnered with the U.S. defense and aerospace giant to build a 10-megawatt power plant using ocean thermal energy conversion (OTEC) technology.

A recently signed agreement between Lockheed Martin, of Bethesda, Md., and the Beijing-based Reignwood Group should lead to the completion of the alternative energy plant by 2017 in waters off southern China’s Hainan Island.

The platform-based power plant will be the largest OTEC application developed to date, according to Lockheed, supplying 100 percent of the power needed for the resort, which will be marketed as a low-carbon real estate development.

The technology involves heating warm surface water to produce steam that drives a turbine generator. Then colder water is pumped from 800 to 1,000 meters below the ocean surface to condense the steam back into liquid form.

Dan Heller, Lockheed Martin’s vice president of new ventures for Mission Systems and Training, said the relationship with Reignwood, a diversified firm with holdings in the energy, minerals, aviation and resort business, solidified as Lockheed engineers went searching for suitable locations to build a pilot-scale OTEC facility.

For several years, Lockheed has tested the technology at a site in Hawaii in partnership with Makai Ocean Engineering, the Energy Department and the U.S. Navy. But several obstacles, including high upfront costs and securing a partner for a long-term project, kept such efforts from growing into a scaled power plant, according to sources familiar with the testing program.

Navy remains interested
Duke Hartman, a spokesman for Makai Ocean Engineering, said that his firm continues to work on OTEC applications in partnership with the Navy, and that the Pentagon has retained its goal of developing a 5-10 MW pilot plant off the island of Oahu and eventually a commercial plant of up to 100 MW.

“The Navy wants a thriving OTEC industry because they would benefit from it,” Hartman said. Imagine being able to tow a semisubmersible power plant to almost any corner of the world, he added.

Hartman said Makai is supportive of Lockheed Martin’s work in China and hopes to be able to participate in the project in some way. “The biggest obstacle to OTEC is economies of scale,” he said. “You get a lot more bang for your buck if you go bigger.”

He estimated that a 100 MW OTEC plant would cost in excess of $1 billion to build using current technologies, and that the cost would not be significantly lower for a scaled-down plant.

Lockheed Martin’s Heller said that Reignwood will bear the full cost of the 10 MW project in south China and that the two firms will continue to seek opportunities to expand OTEC’s foothold in Asia.

U.S. sites with potential
In the United States, Heller noted that several sites, including Hawaii and Florida, have demonstrated potential for commercial OTEC plants, and that Lockheed continues to work to identify partners for OTEC projects at home.

But, he said, when the company began surveying locations for a commercial plant, “China was a very logical place to start” due to its need for clean energy alternatives as well as its location near some of the world’s most ideal oceanographic conditions. Reignwood, he said, was recommended as a development partner because of its commitment to use clean energy to power its resort communities.

Heller said Lockheed Martin will use the Reignwood project to help prove OTEC’s viability as an energy resource with the long-term goal of “building an industry around OTEC,” which has applications beyond electricity generation such as seawater desalination and hydrogen production. And unlike other renewable energy sources, OTEC can be relied on for 24-hour, base-load power.