Tokyo to require solar panels on new small, medium-sized buildings including houses

By Tokyo Metropolitan Government

Tokyo is the central city of Japan with a population of approximately 14 million people who emit greenhouse gases (GHG) equivalent, or about 62 million tons of CO2 per year. In order to fulfill its responsibility as a megacity and play its part in tackling the climate crisis to limit temperature rise to 1.5°C, the Tokyo Metropolitan Government (TMG) has set a goal of achieving carbon neutrality by 2050 and reducing GHG emissions by 50 percent by 2030 compared to 2000 levels.

The TMG aims to raise the percentage of renewable power in the electricity used in Tokyo from 17.3 percent in FY 2019 to 50 percent in FY 2030. Solar panels on rooftops have great potential for increasing renewable power, but it is estimated that only 4 percent of suitable roofs actually have solar installed.

Against this background, the TMG is preparing a program that will require the installation of solar power generation equipment in new small and medium-sized buildings, including houses. The program is characterized by several distinct elements.

First, the program will target suppliers of buildings, not purchasers. The target will also be limited to major businesses supplying a total floor area of 20,000 m2 or more per year in Tokyo to ensure maximum effectiveness and efficiency. The TMG expects that the approximately 50 suppliers under the program will be equivalent to about half of annual construction starts.

Second, the program does not impose obligations on individual buildings, but on the total amount of solar panels installed by each supplier in a year. Suppliers will be able to flexibly plan how many solar panels to allocate to which of the buildings they supply, taking into account the intention of building owners and daylight conditions.

The TMG has already finished collecting public comments on the mandatory program and will submit it to the Assembly after reflecting the opinions of the citizens of Tokyo. The launch of this program will further advance TMG’s efforts toward sustainable urban development.

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