Transition to a 100% renewable grid for a remote island: A case study of Tsushima Island, Japan

Remote islands face unique challenges in achieving carbon neutrality. These islands typically depend on imported fossil fuels, operate independently of larger grids, and experience high electricity costs. Furthermore, limited access to reliable data complicates efforts to design effective energy solutions. Tsushima Island, Japan, exemplifies these challenges. Through a comprehensive analysis informed by a site visit, this study explores the island’s energy landscape and identifies viable renewable resources. Two transition scenarios are proposed to achieve a 100% renewable energy system, addressing key issues such as energy security and sustainability. The findings demonstrate that a complete renewable energy transition is possible, providing a replicable model for other remote islands worldwide. • Two scenarios are developed for the transition of the Tsushima Island electricity grid. • Challenges for transition to renewables for remote islands are addressed. • Cost analysis of different technologies to find optimal scenario is done. • Local meteorological data and utilization of storage systems are proposed to tackle grid stability.