Ocean Thermal Energy Conversion (OTEC), which generates power by utilizing the temperature difference between surface seawater and deep ocean water, is gaining increasing attention. This is not only because of its potential for electricity generation but also due to the diverse business opportunities that arise from the secondary use of deep ocean water. As a Japanese innovation, this technology holds promise for export, not only to remote islands and coastal regions within Japan but also to island nations in the Pacific and Indian Oceans. This paper examines strategies to promote the adoption of OTEC both domestically and internationally.