Tokyo: No solar obligation in the Green Building Program
 Tokyo: No solar obligation in the Green Building Program

Tokyo: No solar obligation in the Green Building Program

Europeans often quote Japan as one of the around 15 countries worldwide, which have approved some sort of solar or renewable building code. This statement, however, is missing serious proof.

The misunderstanding about solar obligations lately might have been fueled by the presentation of Tetsunari Iida at the European Solar Thermal Industry Conference (estec2009) in May in Germany. The Director of the Institute for Sustainable Energy Policies (ISEP) in Japan spoke about a “solar-obligation-type policy” of the Tokyo Metropolitan Government (TMG) and compared the terms “investigation obligation” and “explanation obligation”.

Behind that policy stands the Tokyo Green Building Program, which started in July last year. The TMG made it obligatory to submit a building environmental plan, outlining the environmental measures developers will take into account when constructing new buildings with a floor area larger than 10,000 m2. But the obligation just survives on paper. There is no mandatory regulation, directing to implement measures from feasibility studies that came to a positive conclusion. In a strict sense, this requirement represents no solar obligation and it applies only to large building complexes.

There has been some discussion lately about reducing the stated building size from 10,000 m2 to 5,000 m2 or even to 2,000 m2. This would mean that developers already have to submit an environmental plan for new buildings with a floor area of 2,000 m2 or more.

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Baerbel Epp

Bärbel Epp is Founder and Director of the German communication and market research agency solrico and editor-in-chief of