Updated by the Forest Circular Economy Editorial Department on December 12, 2025, 6:07 PM JST
Editorial Board, Forest Circular Economy
Forestcircularity-editor
We aim to realize "Vision 2050: Japan Shines, Forest Circular Economy" promoted by the Platinum Forest Industry Initiative. We will disseminate ideas and initiatives to promote biomass chemistry, realize woody and lumbery communities, and encourage innovation in the forestry industry in order to fully utilize forest resources to decarbonize the economy, strengthen economic security, and create local communities.
Tokyo Metro has recently concluded a virtual PPA agreement with Sano Biomass Power Generation, funded by Kansai Electric Power and others, for biomass power generation utilizing domestic timber—a first for a subway operator. The agreement will provide environmental value equivalent to approximately 51 million kWh annually for about 19 years from the new biomass power plant to be constructed in Sano City, Tochigi Prefecture. The introduction of biomass as a stable power source will simultaneously advance the company's decarbonization goals and promote the circular utilization of domestic forest resources.
Virtual PPAs are virtual mechanisms that leverage environmental value tied to power generation rather than physically receiving electricity directly from power plants. They enable the procurement of renewable energy even when demand and generation sites are geographically separated, making them an effective decarbonization method increasingly adopted for urban infrastructure with large-scale power consumption. Through this contract, Tokyo Metro will incorporate the electricity value generated by the Sano Biomass Power Plant, thereby expanding its use of electricity derived from renewable energy. Biomass is one type of renewable energy that offers stable output and is less susceptible to weather fluctuations.
The core of this initiative lies in establishing a new supply chain that recycles local forest resources as energy. The Sano Biomass Power Plant, funded by Kansai Electric Power and B-able, will be newly constructed in Sano City. It will utilize domestically produced wood chips made from general timber and unused thinned timber generated in the Kanto region as fuel. Operations are scheduled to commence in September 2028, with an expected power generation capacity of 7.1 MW.
This agreement is expected to reduce Tokyo Metro's annual CO2 emissions by approximately 21,981 tons, equivalent to about 6.51 TP3T. The CO2 reduction effect is comparable to the amount absorbed by approximately 1.56 million cedar trees in one year. The process of forest management will assign economic value to low-quality timber generated during forest maintenance. This will support local forestry operations while enabling the "forest cycle" of nurturing healthy forests to function effectively.
For Tokyo Metro, this agreement also represents a major step toward realizing its "Metro CO2 Zero Challenge 2050." While the company has previously promoted virtual PPAs using solar, wind, and small-scale hydroelectric power, adding biomass power—a stable power source unaffected by weather—will solidify its renewable energy portfolio.
Purchasing environmental value from newly constructed power plants, rather than procuring from existing ones, is highly commendable as an additional renewable energy procurement method. This model, where metropolitan transportation infrastructure connects with regional forest resources to create a two-way economic cycle and environmental conservation, is drawing attention as a pioneering example that achieves both decarbonization and regional revitalization.
Reference Links
Tokyo Metro Signs First Virtual PPA for Biomass Power Generation in Subway System Virtual PPA for Biomass Power Plant Utilizing Domestic Wood | Tokyo Metro
Participation in Biomass Power Generation Project in Sano City, Tochigi Prefecture and Conclusion of Virtual PPA with Tokyo Metro Co., Ltd. Kansai Electric Power Co., Inc.
