Shimizu Corporation, one of the largest general contractors in Japan, has completed a building that emits the world’s least amount of CO2, it has claimed.
Fully opened on August 1st, the Shimizu Headquarters in Tokyo emits 38 kg/m2 of CO2 per year, 62% less on average than ordinary buildings in Tokyo.
Green technology includes an air conditioning system that makes use of radiant heat. Water hoses run under ceiling boards and control the temperature of the ceiling surface.
The surface temperature of 20 degrees absorbs the heat from the office staff through a radiant process. This system is said to reduce CO2 emissions by 30% compared with conventional air conditioning systems.
LED lighting is extensively used and controlled by motion sensors while energy for lighting in the daytime is generated by photovoltaic (PV) panels placed in the outer walls. The 2,000m2 area of PV panels is estimated to generates 84,000 kwh of power per year.
Window shades allow sunlight into the offices and the shade angle automatically changes to follow the sun and optimise natural light. These efforts are claimed to reduce CO2 emissions by 90% compared with standard lighting systems.
By the end of 2015, Shimizu says it will reduce CO2 emissions down to 70% through fine tuning air conditioning and lighting facilities as well as adopting further energy saving systems.