Grid-Scale Battery Storage in Japan: Policy Recommendations for Scaling the Market

The Renewable Energy Institute has released a comprehensive report detailing policy recommendations to scale Japan's grid-scale battery energy storage system (BESS) market. As Japan integrates more variable renewable energy, BESS is increasingly viewed as a critical source of power system flexibility for balancing services and electricity time-shifting. The report highlights that while interest from developers is high, the sector must overcome significant regulatory hurdles and infrastructure bottlenecks to reach its full potential.

The Renewable Energy Institute (REI) report, titled "Grid-Scale Battery Storage in Japan: Policy Recommendations for Scaling the Market," underscores the rapid global expansion of battery energy storage systems driven by declining costs and the rise of variable renewable energy (VRE). In Japan, general transmission and distribution operators have seen a surge in grid connection applications, signaling strong investor confidence in the profitability of grid-scale BESS. These systems are valued for their ability to provide fast-response balancing services and shift electricity supply to meet demand, which is essential for maintaining grid stability as renewable penetration increases.

Despite the growing interest, the Japanese BESS sector faces several structural and regulatory obstacles that hinder deployment. The REI identifies long queues for grid connections and frequent revisions to rules governing revenue-generating markets as primary concerns for developers. Because grid-scale storage is a relatively new business model in the country, stakeholders are grappling with uncertainties regarding market operations and the stability of revenue streams. The report suggests that project developers will need to diversify their income sources and adapt to a rapidly evolving regulatory landscape to remain competitive.

Beyond grid-scale installations, the report examines the status of co-located and customer-sited battery storage systems, identifying shared challenges such as battery costs and economic security concerns. It also addresses social and technical factors, including "Not In My Backyard" (NIMBY) issues and the potential for grid-forming inverters to enhance system reliability. Furthermore, the REI points to a growing interest in Long-Duration Energy Storage (LDES) as a necessary evolution for the market. The report concludes with specific policy recommendations aimed at streamlining grid connection processes and improving market operations to support the large-scale deployment of battery technology across Japan.