TOKYO — Mitsubishi Electric Corp.’s envisioned Net-Zero Energy Building Test Facility has become Japan’s first medium-scale (over 6,000 m2) office building under construction to receive a top-level BELS 5-star rating and Net-Zero Energy Building (ZEB) certification from the Building-Housing Energy-efficiency Labeling System, a third-party certification organization in Japan. The rating, which measures energy-saving performance based on the Building Energy Index (BEI), is for the building’s theoretical performance levels.

Mitsubishi Electric is constructing the Net Zero Energy Building Test Facility in Kamakura, Kanagawa Prefecture, south of Tokyo, to develop and demonstrate ZEB-related technology. The facility is scheduled to start operating in September 2020.

Mitsubishi Electric is promoting technical developments based on its ZEB+ concept of constructing and upgrading buildings over their life cycles for environmental efficiency, energy savings, productivity, comfort, convenience, and business continuity.

The certification recognizes the facility’s projected reduction in energy consumption by 103% (includes production of photovoltaic energy) compared with its surrounding region’s average consumption levels, measuring total energy consumption for air conditioning, ventilation, hot water, lighting, and elevators based on energy conservation standards introduced by Japan’s National Institute for Land and Infrastructure Management in 2016. To qualify for certification, Mitsubishi Electric optimized design conditions for the entire construction process, maximized the efficiency of equipment and systems to be installed in the facility and introduced ZEB-based solutions for air conditioning, lighting and photovoltaic systems. For more information, visit