The “Amendment of Environmental Protection Ordinancce” that requires to install solar panels on new buildings, including single-family houses, in Tokyo was passed and enacted by a majority vote of the Tokyo Metropolitan Assembly on December 15, 2022.  This is the first mandate in Japan that detached houses will be required to install solar panels. After two years of preparation period of support for major homebuilders and other businesses, and building public awareness, the law is scheduled to go into effect in April 2025.

The amended ordinance was passed as originally proposed.

Under the new rule, regarding the obligation of installing solar system and other renewable energy system in houses and small and medium-sized buildings with total floor area of less than 2,000m2, housing companies will be subject to the new rule, and it is expected that around 50 major companies that offer a total floor area of 20,000m2 or more per year in Tokyo will be subject to the obligation.  

Each housing company will be obligated to meet a quota for the total amount of electricity it generates, based on the number of buildings it supplies and the sunshine conditions in each region. New buildings and condominiums with a total floor area of 2,000m2 or more will be obligated by the building owner, who will be required to install 5% of the building area with solar panels.

Although the majority of the assembly voted in favor of this ordinance revision, it is unprecedented in Japan and 41% of the public commenters were opposed to the amendment.  Therefore, in the future, it will be necessary to provide careful explanations and expand various support measures.

* “Environmental Protection Ordinancce”= “Improve the Urban Environment and Protect the Health of Citizens OrdinanceOne of the environmental ordinances to ensure the health and safety of Tokyo residents”

Reference: Hand out by the Tokyo Metropolitan Government, the 4th Energy Countermeasures Headquarters
(Summary of the draft amendment to the Ordinance on Environmental Security, support measures, etc.)