About 90% of Kajima’s CO₂ emissions from its own business activities are generated at construction sites. Of the energy consumed on-site, about 30% is from electricity, and about 70% is from diesel oil used in heavy machinery and elsewhere. As such, it is crucial to reduce the usage of diesel oil and electricity in order to cut the volume of CO₂ emitted at construction sites.

Developing of the Environmental Data Evaluation System (edes) to Reduce Energy Consumption at Construction Sites

We used to ascertain the CO₂ emissions of the Company as a whole using sampling data from studies over a pre-determined period of energy consumption vis-à-vis the value of finished work at construction sites across the country.

However, to reduce CO₂ emissions effectively during construction, we need to know the emissions per construction site and then implement timely measures tailored to conditions at each site.

For this reason, we developed the Environmental Data Evaluation System (edes), which enables users to ascertain and visualize CO₂ emissions for all processes at all construction sites on a monthly basis. It gathers and visualizes statistics on CO₂ emissions during construction, the amount of construction waste, and water usage per-site on a monthly basis. Tried and tested at a model construction site in FY2018, edes has been in full-scale operation since June 2019.

Specifically, we made it possible to ascertain CO₂ emissions during construction by taking information such as the types, numbers, and operating hours of construction machines operated at construction sites, linking this information to existing construction management support services, and automatically importing data into edes. Furthermore, by adding the CO₂ emissions derived from electricity and fuel used in vehicles to transport soil, sand, and waste, it is now possible to ascertain the data per construction site on a monthly basis.

Going forward, we will accelerate efforts to create a carbon neutral society as stated in Triple Zero 2050 by comparing the data at each construction site and branch office to formulate effective reduction measures and deploy these measures across the country.

Genba de Eco ("On-Site Eco")

Devising ways to reduce the consumption of diesel and other fossil fuels and to eliminate inefficient material waste and construction methods leads to CO₂ emissions reduction and on-site cost savings. Using the "Genba de Eco" ("On-Site Eco") intranet site created by Kajima, worksite personnel access tools for reducing CO₂ emissions, select reduction options based on the scale of construction, and calculate the overall reduction amount. This system allows users to easily compare CO₂ emissions reduction plans based on the scale of construction.

In the life cycle of a building, the operational phase is the longest and the most CO₂ intensive. Kajima designs buildings with eco-friendliness and energy-savings in mind so that energy consumption will be as low as possible when completed buildings are delivered to clients and actually used by customers.

Kajima has made "construct new buildings as ZEBs/ZEHs from FY2030 on" an objective and is carrying out technology development and demonstrations using its own facilities.

Known for its outstanding design and construction capabilities, Kajima constructs not only mega solar power generation facilities, but also renewable energy power generation facilities, such as offshore wind power generation facilities and food-waste biomass power generation facilities.

Of the seven material issues that Kajima identified in FY2019 for achieving the SDGs, this falls under "Environment 4: Contributing actively to society’s transition to a carbon-free footprint."