*1 Heating system used in "Sony City," Sony headquarters building earns COP 5.19, the highest rating under Japanese efficiency standards. (Calculated the average values measured from January 2007 to April 2008, based on Sony data)
*2 Operation of this building annually produces approximately 48% fewer CO₂ emissions than conventional buildings. (Based on Sony data)

Hope for designing a state of the art environmental building through taking the advantage of energy-saving technologies that have been developed in plants, research institutes, and manufacturing processes is the source of creating "Sony City," Sony headquarters building completed in October 2006.
The most characteristic feature of the headquarters building is that it applies treated wastewater to air conditioning for the building. The wastewater is provided by Shibaura Water Reclamation Center, Bureau of Sewerage, Tokyo Metropolitan Government, located next to the building. Urban areas have a problem with heat island effect caused by heat exhausted from a cooling tower located on the roof of the building. With this in mind, Sony thought that it should utilize water discharged from the Water Reclamation Center as substitute for the cooling tower. This is exactly an example of our recycling philosophy. Sony developed a system where approx. 60 thousand square meters of treated wastewater per day flow from the Water Reclamation Center through pipes to Sony headquarters building. It is rather exceptional for a private company to sign a contract with a local government to use its treated wastewater in Japan, and as far as this Water Reclamation Center is concerned, Sony was the first private company to do so. Joining hands with the neighbor to save energy is Sony’s commitment to the environment.

Other many ideas are also behind this building. One of the examples is a full-height glazing structure. At first glance, its exterior wall seems design-oriented, but in fact, it uses a double glass facade system called "double skin." It is as if people wear several layers of clothing. Actually, a blind set between the double glass plates blocks the sunlight while it allows the warm air generated between the glass plates to escape from the building through natural convection. In addition, "Sunflower," a device located on the roof of the building detects the sun direction as well as amount of insolation to automatically control tilt of the blind. The tilt helps to maintain comfortable temperature inside the building. Moreover, a variety of environment-conscious features covering power source, heat source, air conditioning and lighting are implemented in the headquarters building. Examples are; 1) introduction of the most advanced(*3) air conditioning system used in Kumamoto factory, 2) installation of power storage batteries to make the most of the power charged during the nighttime in the daytime, 3) installation of photosensors and infrared sensors. As a result, this building produces approximately 48% fewer CO₂ emissions than conventional buildings, which substantially exceeded our expectation. Sony applies various energy-saving measures developed by its technological excellence to its offices. The Sony vision of a greener future is well underway.