Using Energy Effectively by Combined Heat and Power (CHP) SystemsTokyo Gas started its energy saving efforts early with the introduction of a CHP system*1 at the Hamamatsucho Head Office Building in 1984. We upgraded the system to one employing the most advanced technology*2 and started using the new system in April 2009. The replacement allowed the building to reduce its annual CO2 emissions by about 1,400 tons.
The TG Hiranuma Building That Received Environment Minister’s Award for Global Warming Prevention Activity
*1 The government gives subsidies for leading housing and construction projects for CO2 emission reduction after publicly soliciting applications.
*2 The Building Energy-Efficiency Labeling System. In the system, a third-party evaluation body assesses and certifies the energy-saving capabilities of green buildings under the Act on the Improvement of Energy Consumption Performance of Buildings (Building Energy Efficiency Act).
*3 A zero-energy building (ZEB) aims to achieve zero net primary energy consumption, or the equal balance between total energy used and renewable energy generation, on an annual basis. The government is promoting such buildings, putting the initiative into its basic energy program.
Earth Building Tachikawa (TG Tachikawa Building) Given Top CASBEE CertificationThe Earth Building Tachikawa (TG Tachikawa Building), rebuilt because of aging, was completed in July 2015 as a middle-scale office building (five stories above ground, about 10,600 m2).
*4 CASBEE stands for the Comprehensive Assessment System for Built Environment Efficiency, which assesses environment performance of buildings and gives ratings on a scale of five.
Earth Port as ZEBWe started to take improvement measures at the Tokyo Gas Kohoku New Town Building, dubbed Earth Port, in 2010 to achieve zero net primary energy consumption on an annual basis by 2030 by making equipment more efficient and optimizing energy use at a number of buildings. Measures including renewable energy use, such as solar thermal and photovoltaic power generation, and optimum operation of its CHP system allowed the building to reduce its primary energy consumption by about 49% and CO2 emissions by about 54%.
Saving Energy through Better Use of Equipment, FacilitiesWe hold an energy-saving committee at each building where we lease an office, among the building’s owner and equipment administrator and the relevant section of ours. The committee helps examine energy use, optimize temperature and humidity and arrange energy conservation patrols, encouraging each of our employees to promote energy-saving activities.
Example of visualization at Hamamatsucho head office building
Poster for an energy conservation campaign
The Gas Science Museum started to purchase electricity from ENNET Corporation under its Green Menu*1 electricity program. This is the Tokyo Gas Group’s first electricity purchase through non-fossil fuel certification in the FIT*2 program. The museum covers about 70% of is power consumption with electricity generated by highly efficient fuel cells using natural gas. This time, the museum has decided to shift its electricity procurement that covers the rest of about 30% to the purchase from ENNET. The shift is estimated to reduce CO2 emissions in fiscal 2018 at the museum by 17%*3 from fiscal 2017 to 75 tons.
*1 An ENNET program featuring a CO2 emission factor of zero. Of electricity provided under the program, Tokyo Gas purchases electricity from renewable energy sources by using non-fossil fuel certification in the FIT program.
*2 The feed-in tariff program, in which the government assures that power companies purchase electricity from renewable energy, such as sunlight, wind power, hydraulic power, geothermal heat and biomass.
*3 The estimate assumes energy consumption at the museum remains the same from fiscal 2017.