According to Japanese Technology May Help Islands Reap Pacific’s Waters, Saga University has developed a technology that generates power while simultaneously desalinating ocean water for drinking:
The university is preparing to build an experimental power plant off the coast of Palau that brings up cold seawater from the depths of the sea to an evaporator chamber near the ocean surface.As the water is heated by the surrounding warm surface water, it releases ammonia gas, which then drives the system’s power generator, said Yasuyuki Ikegami, deputy director of the Institute of Ocean Energy at Saga University.
Meanwhile, the heated water would be transferred to a separate low-pressure chamber where it boils at a lower temperature, producing steam, which would be condensed and collected as fresh water for human consumption, leaving salt crystals behind.
One experimental system, which produces power but no usable water, is scheduled to be put into use off the coast of India this month, Mr. Ikegami added.
“It works well especially in the western Pacific, where the temperature difference between the ocean’s surface and deep seawater is” as much as 43 degrees Fahrenheit, he said. “It is environmentally sound.”