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Mitsubishi Electric's Net Zero Energy Test Facility Cuts Annual Operating Energy to Below 0%New ZEB operational technology reduces standard primary energy consumption by 115% in first year


TOKYO, November 15, 2021 - Mitsubishi Electric Corporation (TOKYO: 6503) announced today that its SUSTIE® net zero-energy building (ZEB) test facility, which launched at the company's Information Technology R&D Center (Kamakura, Kanagawa Prefecture) in 2020, reduced its energy consumption to less than 0%, meaning that it created more energy than it consumed, in its first full year of operation. The facility, a medium-sized office building with more than 6,000m2 of floor space and equipped with solar panels, deployed ZEB operating technology to optimize operations, resulting in a 115% reduction in energy use compared to standard primary energy consumption as specified in Japan's Building Energy Conservation Law (values differ according to region and building use). The results demonstrate that ZEB-level operation is possible even in dense urban areas while maintaining a highly comfortable and productive work environment.

  • SUSTIE ZEB test facility

  • Annual primary energy

Immediately after SUSTIE began operating, newly developed ZEB operating technology was deployed to simulate the use of building equipment, such as air conditioning and lighting, including temperature and brightness, to predict energy consumption and comfort levels for a one-year period. The technology conducted repeated simulations in combination with multi-objective optimization technology using Mitsubishi Electric's proprietary AI technology Maisart®1 to generate a building operating plan that balanced energy consumption and human comfort, resulting in energy creation of 571.75MJ/m2, energy consumption of 366.07MJ/m2 and an energy balance of -205.68MJ/m2 (all figures annual).
The technology was shown to reduce the time required for trial-and-error setting of facility parameters, such as temperatures, light dimming rates, etc. for each room, which enabled the building to achieve ZEB-level operation in its first year beginning from the first day of occupancy (October 19, 2020, to October 18, 2021).

  1. 1Mitsubishi Electric's AI creates the State-of-the- ART in technology Maisart


Note that the press releases are accurate at the time of publication but may be subject to change without notice.


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