The third report of the “Renewable Energy for Regional Revitalization” series, which highlights local cities working to deploy renewable energy for regional revitalization, focuses on Miyakojima City in Okinawa Prefecture.
Located 300 kilometers southwest of Okinawa’s main island, Miyakojima attracts large numbers of tourists with its beautiful beaches and coral reefs. One of the city’s challenges is achieving greater energy self-sufficiency. With an isolated power grid serving the islands, Miyakojima must meet the electricity demand of both its residents and nearly one million tourists. Its main source of electricity is heavy-oil-fired diesel generation, making the city vulnerable to fluctuations in fuel prices while also producing large amounts of CO₂ (carbon dioxide). Typhoons approach the islands several times a year, involving an additional risk of power outages. When Typhoon No. 9 approached in July 2026, approximately 14,000 households, about half of all households in the city, experienced power outages lasting up to three days.
As a countermeasure, Miyakojima City has been promoting the widespread adoption of solar power generation and battery storage systems. At more than 1,100 homes and private-sector facilities equipped with solar panels and batteries, residents and businesses were able to continue using essential equipment such as air conditioners, refrigerators and water pumps throughout the three-day outage. Even under normal conditions, these systems also help reduce monthly electricity bills by around 10% compared with Okinawa Electric Power Company’s standard electricity plan.
On Kurimajima Island, adjacent to the main island of Miyakojima, a local microgrid powered by solar generation and battery storage is in operation. During power outages, the microgrid can disconnect from the main power grid and continue supplying electricity independently to every household within the microgrid.
Series “Renewable Energy for Regional Revitalization” (all contents are in Japanese)
This series highlights innovative initiatives by local governments that use renewable energy to address local challenges, including promoting local energy production and consumption, creating new industries, and improving public services. Through examples from municipalities across Japan, the series shares insights into advancing renewable energy in ways that benefit local communities.
No.1 Utilizing Offshore Wind and Biomass to Attract Data Centers, a Growing Industry (Ishikari, Hokkaido) 16 July 2025No.2 From Disaster to Resilience: Solar Power and Batteries Drive Recovery and Energy Independence (Miyako, Iwate) 17 December 2025
No.3 An Island Where Solar Power and Batteries Protect Residents’ Daily Lives (Miyakojima, Okinawa) 2 September 2026
