MITSUBISHI ELECTRIC CORPORATIONPUBLIC RELATIONS DIVISION
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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 yearTOKYO, November 15, 2021 – Mitsubishi Electric Corporation (TOKYO: 6503) announced today that itsSUSTIE® 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 lessthan 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 ispossible even in dense urban areas while maintaining a highly comfortable and productive work environment.

Annual primary energy

SUSTIE ZEB test facility

Immediately after SUSTIE began operating, newly developed ZEB operating technology was deployed tosimulate the use of building equipment, such as air conditioning and lighting, including temperature andbrightness, 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
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and human comfort, resulting in energy creation of 571.75MJ/m2, energy consumption of 366.07MJ/m2 andan 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, suchas 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 Mitsubishi Electric's AI creates the State-of-the- ART in technology

Overview of SUSTIE
Location

5-1-1 Ofuna, Kamakura, Kanagawa Prefecture, Japan (premises ofInformation Technology R&D Center, Mitsubishi Electric Corporation)

Size and type

Building: 1,954m2; Total floor space: 6,456m2; 4-story steel-frame
Designphase

Annual energy consumption:499.94MJ/m2
Annual energy creation: 583.66MJ/m2
World-leading BEI3 primary energy consumption evaluation index of -0.06(or 0.37 excluding solar power-energy generation)

Operation
phase

Annual energy consumption:366.07MJ/m2
Annual energy creation: 571.75MJ/m2
World-leading BEI primary energy consumption evaluation index of ‐0.15(or 0.27 excluding solar power-energy generation)

Energyperformance2

Certifications4

BELS 5-star (☆☆☆☆☆) rating and 『ZEB』5 certification from
Building-Housing Energy-efficiency Labeling System (BELS), a third-party
certification body in JapanCASBEE Wellness Office certification “S rank” from Institute for Building
Environment and Energy Conservation
WELL Building Standard® preliminary certification “platinum level” fromInternational WELL Building Institute™

2 Design phase based on WEBPRO values and operational phase (10/19/20–10/18/21) based on actual measured values.

WEBPRO is an energy consumption performance calculation program of the Building Research Institute.
3 Ratio of primary energy consumption at time of design compared to standard primary energy consumption.
4 First building in Japan to obtain highest ranks of these three certifications (as of November 15, 2021, internal research).
5 Highest ZEB ranking in BELS certification system.

Feature of ZEB Operation Technology1)

Building simulator supported with digital twin
- Digital twin reproduces building conditions with great precision, using building information such as floorarea, insulation performance, etc. as well as building equipment type and performance in BIM6 format.
- Energy consumption and comfort predictions based on temperature settings, dimming rates, changes inoccupancy, annual climate, etc.
6 Building Information Modeling is a method for centrally managing and utilizing information on building lifecycles (planning,design, construction, and operation), including three-dimensional information on buildings and their equipment.

2)

Multi-objective optimization technology used to optimize annual operating plan
- Multi-objective optimization technology using Maisart is used to develop an operating plan thatminimizes energy consumption and maximizes comfort, seemingly conflicting objectives.
- Using AI, the new technology quickly searches for the prediction that best balances energy
consumption and comfort, based on 2,500 calculations instead of the theoretically required 1,000
trillion calculations, and thereby devising an optimal operating plan.
2/3Pre-planning ZEB operation technology used in SUSTIE

About Maisart
Maisart encompasses Mitsubishi Electric’s proprietary artificial intelligence (AI) technology, including its
compact AI, automated-design deep-learning algorithm and extra-efficient smart-learning AI. Maisart is anabbreviation for "Mitsubishi Electric's AI creates the State-of-the-ART in technology." Under the corporate
axiom "Original AI technology makes everything smart," the company is leveraging original AI technology
and edge computing to make devices smarter and life more secure, intuitive and convenient.
SUSTIE and Maisart is a registered trademark of Mitsubishi Electric Corporation.
WELL Building Standard is a registered trademark of International Well Building Institute PBC.

###About Mitsubishi Electric Corporation
With 100 years of experience in providing reliable, high-quality products, Mitsubishi Electric Corporation(TOKYO: 6503) is a recognized world leader in the manufacture, marketing and sales of electrical andelectronic equipment used in information processing and communications, space development and satellite
communications, consumer electronics, industrial technology, energy, transportation and building equipment.
Mitsubishi Electric enriches society with technology in the spirit of its “Changes for the Better.” The company
recorded a revenue of 4,191.4 billion yen (U.S.$ 37.8 billion*) in the fiscal year ended March 31, 2021. For
more information, please visit www.MitsubishiElectric.com*U.S. dollar amounts are translated from yen at the rate of ¥111=U.S.$1, the approximate rate on the Tokyo
Foreign Exchange Market on March 31, 2021

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