Technology Transfer Brings Seawater-Based New and Renewable Energy One Step Closer to Commercialization

– KRISO will transfer its high temperature difference, ocean thermal energy conversion (H-OTEC) technology to a private company, to be utilized for new offshore plant export and official development assistance (ODA) – 

□ The Korean government is busy making preparations to provide policy support to the new and renewable energy field in response to the launch of the post-2o2o climate regime under the Paris Agreement adopted last year.

○ Against this backdrop, the Research Institute of Ships and Ocean Engineering (“KRISO” hereinafter, President Suh, Sang-hyun) under the Korea Institute of Ocean Science and Technology garnered much attention when it signed a contract on March 4 to transfer its technology to generate energy using high temperature difference, ocean thermal energy conversion (H-OTEC) to a private company.

□ H-OTEC is a complex high temperature difference generation technology that uses deep and surface seawater as a thermal probe, and unused heat such as geothermal heat and industrial waste heat as a heat source to circulate a working fluid into a cycle to generate electricity. The Seawater Utilization Plant Research Center (Director Kim Hyun-joo) succeeded in developing this technology.

□ Ocean thermal energy conversion (OTEC) is a method to generate electricity by repeating a process of evaporating ammonia that vaporizes at a low temperature and then chilling the vapor into a liquid state with cold deep seawater. The pressure difference occurring during this process is used to run a turbine for power generation.

○ Meanwhile, H-OTEC uses cold deep seawater or coastal bottom water as a heat probe in the same generation cycle described above, but offers much higher generation efficiency as it uses geothermal heat, solar heat, or waste heat from industrial processes as a heat source.

□ The H-OTEC plant developed by KRISO uses an oil-less bearing system to which a highly efficient, radial inflow turbine and air bearing are applied, and has acquired a high generation efficiency rating (7.7%) from performance testing by a certified agency.

○ Five 200 kW-grade, H-OTEC plants will be installed side-by-side for operation, which is expected to help Korea respond better to climate change by generating 8,322 MWh of new and renewable energy annually to replace 1,756 TOE of oil and to reduce carbon dioxide emissions by 3,759 tons annually.

* TOE (Tonnage of Oil Equivalent): Energy generated from burning one ton of oil. 1 TOE is 10,000 kal.

□ KRISO, a government-funded research arm under the Ministry of Oceans and Fisheries, succeeded in developing a 200 kW-grade H-OTEC system using Korea’s own technology through industry-university-institute collaboration in 2014.

□ Director Kim of the Seawater Utilization Plant Research Center remarked, “H-OTEC can be put into practical use in Korea where it is easy to take advantage of deep seawater or coastal bottom water by using waste heat from the industrial processes and incineration heat. It also has great potential to address power shortage in equatorial island nations blessed with plenty of thermal heat and solar heat. This technology can be utilized not only in the export of new offshore plants to meet the demands arising from the new climate change regime but also as a way to provide ODA to island nations in the Pacific Ocean.”