Japan pilots low-weight solar panels, perovskite windows for buildings

Share

Mitsui Home and Tokyo Gas have agreed to deploy Japan’s first combined on-site and virtual power purchase agreement (PPA) using thin, lightweight solar panels at Mitsui Home’s factory in Saitama prefecture.

Tokyo Gas said in an online statement that it will install a 1 MW system across the plant’s full roof surface, enabled by panels that weigh about 40% less than conventional modules.

The on-site PPA will supply the factory directly, while surplus generation will be sold to the market with its environmental value transferred to Mitsui Home’s Chiba and Kansai factories through a virtual PPA.

The project is expected to deliver about 1,170 MWh of renewable electricity annually and cut Mitsui Home’s domestic factory emissions by roughly 506 metric tons, equal to a 44% reduction across its Saitama, Chiba, Kansai and Kyushu sites.

The companies described the arrangement as a model for addressing rooftop load limits and surplus-power constraints as Japan seeks to expand solar capacity under the Seventh Strategic Energy Plan amid a shortage of suitable land.

The initiative also complements other ongoing innovation across Japan’s renewable and energy storage sectors.

In January, for example, Japan reinforced its lead in solid-state batteries, backing four major R&D projects by Toyota, Idemitsu, Mitsui Kinzoku, and TK Works with over $660 million in subsidies to support commercialization by around 2030.

In July, PXP Inc and Tokyo Gas began developing lightweight chalcopyrite solar cells for low-load industrial roofs, while a consortium including Toshiba and YKK AP started a perovskite window pilot at Tokyo’s Telecom Center Building.

This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.

Popular content

SMA launches new containerized medium-voltage substation for large-scale BESS and solar plants
04 December 2025 SMA Solar Technology announces the commercialization in Europe of its new MVPS-9200 medium voltage station in a 12-meter containerized version for bat...