Although there are no regulations in Japan mandating the percentage of renewable energy in energy consumption, several Japanese prefectures and local governments have made the installation of renewable energy mandatory for buildings that meet certain conditions.

For example, the Tokyo Metropolitan Government passed an ordinance in December 2022 making the installation of solar panels mandatory for new residential buildings with a roof area of 20 square meters or more, and a total floor area of less than 2,000 square meters. The ordinance is due to take effect in April 2025.