[Brief translation]
In light of the Kyoto Protocol's entry into force, all eyes are on the ocean thermal energy conversion technology being developed by Saga University for clean energy use.
Ocean thermal energy conversion involves the use of an ammonia-water mixture to heat and vaporize surface seawater that has been warmed by the sun in order to power turbines in a power-generating cycle that later uses the cold seawater at a depth of 800 meters or more below the surface to cool and condense the steam to produce fresh water. The sun and the ocean, inexhaustible sources of energy, power the operation.
The conversion process involves pumping large volumes of seawater. After the heated water goes through a heat exchanger, it enters a vacuum tank, is vaporized, and 1-2% becomes fresh water. In desertified countries such as Saudi Arabia, this water desalination plant function is highly sought after, and in March 2004 Saudi Arabia invested its own capital to establish a joint venture with the Japanese company that holds the rights to use the Saga University patents.