Start of Verification Testing of the Energy Conservation Effects of a Next-Generation Office

Proving its energy conservation effects by collecting and analyzing data while operating with employees actually in the office

June 3, 2010Takenaka Corporation

Takenaka Corporation (President: Toichi Takenaka) will begin verification tests of its next-generation office designed to minimize energy consumption at the TAK Shinsuna Building (Koto Ward, Tokyo) completed in April of this year as the headquarters of Takenaka’s affiliate, TAK E-HVAC Co., Ltd. This testing, conducted with financial support from the New Energy and Industrial Technology Development Organization (NEDO), will compare the Next-Generation Office Room, which masterfully combines the three basic technologies—air conditioning, lighting, and control developed by Takenaka Corporation—with ordinary office rooms in the same building, proving that it controls CO2 emissions to less than two-thirds of the level for ordinary office rooms.
The test is scheduled to continue for about three years, from May of 2010 to May of 2013. With the room in operation while employees actually occupy its space, data will be collected and analyzed to quantify its energy saving effectiveness in order to complete the comprehensive evaluation and verification of the system.
Based on the achievements of this research, office space which simultaneously conserves energy and ensures comfort will become a reality.

【Verification test method】

In the TAK E-HVAC CO.’s Shinsuna headquarters building, a Next-Generation Office Room with floor space of approximately 170 square meters has been constructed along with about 1,000 square meters of ordinary office rooms equipped with facilities in wide use in present day buildings, to compare the energy saving effects of the equipment serving the two spaces.
The Next-Generation Office Room is equipped with the 1) Chuon-Eco® (Medium Temperature Eco) air-conditioning system, film radiant air conditioning, and personal air conditioning, 2) ceiling and table top LED lighting, and 3) a control system integrating the air conditioning and lighting.
In contrast, the ordinary office rooms were serviced by 1) building multizone air conditioning (air-cooled heat pump packaged heat source) and 2) fluorescent base lighting (750lx on desk tops), which are in wide use in present day buildings.
A trial calculation at the research stage revealed that the electric power consumed per square meter in the Next Generation Office Room would be less than two-thirds of that in the ordinary office room. Measurements made during this test confirmed this result.

【Technologies used to perform the verification test】

The following three technologies were installed in the Next Generation Office Room for this verification test.

1.Air-conditioning technologies (Chuon-Eco® (Medium Temperature Eco) air-conditioning system, film radiant air conditioning, and personal air conditioning)

Chuon-Eco® (Medium Temperature Eco) air conditioning was used to improve energy efficiency. This system is composed of building multizone air conditioning and a humidity control outdoor air processor, which increases the evaporative temperature of the refrigerant. Film radiant air conditioning conditions the air by blowing a gentle flow of air which room occupants barely feel from a film surface on the ceiling. Personal air conditioning is a system which allows an individual setting at a desk to use a PC, etc. to adjust the air flow sensation to match his or her personal taste and activity level, enhancing office workers’ satisfaction with the temperature. Where an air-conditioning system combining these is in operation, a casually dressed person in a room where the temperature is 28 degrees centigrade can sense a temperature equal to that felt by a person wearing a suit in a room at a temperature of 25 degrees centigrade.

2.Lighting technology (LED equipped desktop and ceiling lighting)

Long-life and high-efficiency LED are adopted to provide ceiling lighting and desk-top lighting which serves as work-place lighting. The ceiling lighting is provided by LED lighting installed behind the air-conditioning film, which is made of translucent materials. Even with the illuminance of the lighting controlled, it maintains a feeling of brightness throughout the room by emitting light from a wide area of the ceiling. This ceiling lighting is set to ensure approximately 400lx on desk tops, but the joint use of desk-top lighting ensures brightness required for actual work.
While controlling overall lighting, workers individually control the lighting to ensure the illuminance each requires according to circumstances, thereby cutting energy consumption.

3.Control technologies (control by using sensors)

Wasteful operation is prevented by integrated control of motion, illuminance, and radiant heat sensors, temperature and humidity sensors, seating sensors, and all other equipment. A seating sensor, for example, detects people occupying seats, lowering the lighting around unoccupied seats. The personal air conditioning and desk-top lighting can also be controlled by individual terminals. A a personal terminal can also be used to monitor energy consumption, enhancing users’ awareness of energy conservation. Workers also operate and monitor the system from their personal computers or cell phones.

<Image of a Next-Generation Office Room>

photo:External view of the electrolytic cell、Residual chlorine measurement、Control panel