Home battery storage aggregation projects have launched with participation of Tokyo Electric Power Co, and Tokyo Gas, two major utility companies in the Japanese capital.
On Tuesday (3 September), power management company ENERES announced the start of a demonstration project to evaluate the remote control and dispatch of residential energy storage systems.
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Several megawatt-hours of residential battery storage systems, typically paired with solar PV, are being installed in Japan on a monthly basis.
This is largely due to concerns about losing power at home, given the seismic activity the country is frequently subject to, as well as extreme weather events like typhoons. There are also economic and ‘green’ rationales, including increasing self-consumption of onsite generated solar energy to lower electricity bills, particularly as feed-in tariff (FiT) schemes have been phased out or offer much lower prices for export than before.
A late 2023 report from BloombergNEF identified Japan as one of the five biggest residential battery storage markets in the world, alongside Germany, the US, Italy and Australia.
Customer-sited battery systems made and marketed by Japanese manufacturer Kyocera will be used by ENERES to help manage the supply-demand balance of electricity on the grid in partnership with utility Tokyo Electric Power Co (TEPCO) and a TEPCO distributed energy resources (DERs) subsidiary.
ENERES said Kyocera customers will be invited to enrol into the programme, running until the end of this year.
TEPCO will instruct ENERES on the supply and demand situation and instruct it to charge and discharge battery systems accordingly, while ENERES will provide Kyocera with a daily plan for control based on electricity spot price forecasting.
Kyocera will conduct the actual control of the batteries, using ENERES’ energy management system (EMS) technology. ENERES will monitor the charging and discharging at 10-minute intervals, making corrections or adjustments as required.
The project will assess the suitability of the batteries for adjusting the grid’s supply balance during times of peak demand and low generation, in terms of technical capability and the scale and capacity of resources required, as well as economic factors. Based on the outcome, the four partner companies will “continue to explore residential demand response (DR) services” and how they can contribute to Japan’s goal of a carbon neutral society by 2050, ENERES said.
The company’s ENERES Power Marketing arm was recently selected as one of nine aggregation partners to a government-funded scheme to scale up DR from residential and commercial & industrial (C&I) customer-sited behind-the-meter (BTM) assets including batteries.
Tokyo Gas to control own installations
Another Tokyo-headquartered utility, Tokyo Gas, also began a similar programme with residential batteries.
The company markets and installs battery storage systems to households, and also has a new solutions service, branded Igniture, which controls the charging and discharging to participate in power supply-demand balancing.
Tokyo Gas opened its Battery Control Service programme to customer enrolment on 26 August, offering an upfront fee of ¥10,000 (US$70) for joining and ¥200 per month thereafter.
The utility said customers will continue to be able to use their systems for backup power and solar PV self-consumption applications while Tokyo Gas uses them for DR applications.
The programme is a renewal of a previously launched DR service from Tokyo Gas, leveraging its new Igniture brand which it established last year. Tokyo Gas is also participating in the Japanese utility-scale battery energy storage system (BESS) market, signing a 20-year tolling offtake deal with Australian developer Eku Energy for a forthcoming 30MW/120MWh project.
Market to open up in FY2026
In a separate release last week (26 August), ENERES said it has launched the third phase of an initiative to evaluate how electric vehicles (EVs) and residential stationary batteries can participate in combination to provide supply-demand adjustment to the power grid.
The Energy Systems Integration Social Collaboration Research Division (ESI) is also participated in by 17 other companies and a team from the University of Tokyo. ENERES noted that this effort comes ahead of the opening up of the power balancing market to these distributed low-voltage resources, which will happen in Japan’s financial year (FY) 2026.
