NTT Anode Energy Corporation, Kyushu Electric Power Company (Kyuden), and Mitsubishi Corporation officially started operations of a 1.4 MW / 4.2MWh grid-scale battery storage system in Tagawa-gun, Fukuoka Prefecture, marking a significant milestone in Japan’s journey toward renewable energy.
The implementation of this system is expected to boost the country’s use of solar power by minimizing the necessity for solar power curtailment when output exceeds demand.
Japan’s push to become carbon neutral by 2050 has heightened the focus on making renewables a core part of the country’s energy composition. The challenge lies in managing surges in renewable energy generation, with curtailment becoming an increasing issue in areas like Kyushu and across Japan since spring 2022.
In fiscal 2023, curtailment in the Kyushu region alone is projected to lead to the loss of about 740 GWh of power, sufficient to energize 170,000 homes for a year. To address this, the three companies have combined their resources since June 2022 to devise methods that effectively utilize surplus solar power and foster additional power reserves.
The newly installed grid-scale battery system in Tagawa-gun signifies the companies’ first initiative to minimize the curtailment of surplus renewable energy and ensure a steady power supply when the supply-demand balance is tight. The battery system underwent 47 charge and discharge cycles from April to June 2023, handling a total energy charge and discharge of 260,000 kWh.
The companies are embarking on two key validations. Firstly, the practicality of the business model is being assessed, with the multi-use of batteries in various power markets, such as spot markets, supply-demand adjustment markets, and capacity markets. Secondly, the synchronous operation of multiple solar power plants is being tested to minimize curtailment and optimize the use of renewable energy.
The consortium aims to supply power to Japan’s capacity market from fiscal 2025. While working to reduce solar power curtailment, the companies will also explore growth opportunities for their ventures in the renewable energy sector.