Protecting the precious environment
Energy & CO2

We are working on reduction of CO2 emissions in an effort to create a low-carbon society.

Reduce CO2 emissions in the construction stage

CO2 emissions

In order to reduce CO2 emissions in the construction stage, we are rigidly enforcing the prevention of vehicle idling and appropriate maintenance of construction machinery and vehicles, etc. at each construction site.

CO2排出量の推移 グラフ

Reducing CO2 based on industrial waste disposal contractor designation system

Industrial waste generated at construction sites are separated by item (e.g., wood waste, waste plastics, mixed waste) and disposed of by designated companies. Among them, mixed waste has been substantially reduced but are generated over a long period of time from commencement of construction to completion at the site.

From among 6 designated companies and 12 plants in the Tokyo region and 6 designated companies and 11 plants in the Kansai region, we select a disposal contractor that is close to the site and thereby reduce the waste transportation distance, which translates into improved waste collection and transportation efficiency as well as lower CO2emissions.

Reducing CO2 through effective on-site use of soil generated from construction

Nearly approx. 90% of CO2 emissions generated at construction sites is attributable to the use of light oil, so the usage of light oil substantially affects the reduction of CO2 emissions.

In recent years, soil landfill sites have become further away, so CO2 emissions generated during soil transportation tend to increase.

At construction sites, we use the soil generated from excavating works as backfill soil on the site to the greatest extent possible in an effort to reduce the number of dump trucks carrying the soil outside the site and thus reduce CO2 emissions.

Most of the surplus construction soil carried outside the construction site is disposed of in the form of landfills, which may cause the destruction of the environment. Reducing the transportation volume of surplus soil will also help protect the environment.

Wakashio Heights Reconstruction A (Tokyo region)

In the Wakashio Heights Reconstruction A (Mihama City Kemigawahama Block I) construction project, approximately 3,500m3 of 7,700m3 of the earth and sand excavated to remove roots from the ground was temporarily stored at the site, covered with protective sheets to prevent the dispersion of dust to the neighborhood, and then it was backfilled as the construction work proceeded. This on-site utilization of excavated earth and sand resulted in fewer trucks to carry earth and sand out of the site and a CO2 emissions reduction of about 41 tons.

Wakashio Heights Reconstruction A
(Mihama City Kemigawa-hama Block I)

Higashi-Ku Chayagasaka Project Phase 2 Construction Project (Kansai region)

In the Higashi-Ku Chayagasaka Project Phase 2 Construction Project (provisional name: MEGA CITY TERRACE II ),earth and sand excavated to remove roots from the ground was temporarily stored at the site and backfilled to build a foundation. The on-site utilization of approximately 2,900m3 of excavated earth and sand resulted in fewer trucks to carry earth and sand out of the site and to bring in backfill earth and a CO2 emissions reduction of about 20 tons.

Higashi-Ku Chayagasaka Project Phase 2
Construction Project (provisional name: MEGA CITY TERRACE II)

Reducing rainforest-sourced materials and environmental burden

Plywood for concrete formwork is made of materials sourced from rainforests. Loss of vast rainforests means losing a huge CO2 absorber, so there is an urgent need to preserve them also from the viewpoint of biodiversity.

In the construction division, we are advancing our efforts to use precast concrete (PCa) units for handrails and edges of corridors and balconies, decorative columns, exterior stairs, floors and rooftop parapets, in addition to employing the ALC method for non-load bearing walls. We also use steel formworks and plastic formworks where possible in order to reduce the use of plywood formworks made of rainforest wood.
In fiscal 2020, we achieved a reduction of the use of rainforest wood by 10.5% or equivalent to 146,751m2 in the Tokyo region and by 32% or equivalent to 171,732m2 in the Kansai region.
Replacing wooden formworks by industrial products or alternative formworks or other products has led to reduced waste in preparing formworks and fewer concrete mixer trucks, which contributes to reduction of industrial waste and CO2 emissions.

rooftop parapets
PCa exterior stairs

Use of biomass electric power

Since November 2020, we have implemented for verification an initiative to utilize renewable energy as a temporary power supply at construction sites. In this effort, we utilize electricity produced by biomass power generation, which uses waste wooden materials generated at our construction sites as part of its fuel.

Contribution to CO2 emissions reduction

This initiative can reduce CO2 emissions from power generation, as compared with the case of using electricity supplied from conventional thermal power plants, contributing to the mitigation of global warming.

Environment-Conscious Initiatives at the Design Stage

Utilizing CO2 Emissions Calculation Sheet

In April 2017, we revised Haseko Corporation’s proprietary “CO2 Emissions Calculation Program,” which we had continued to operate since its development in 2011. Based on the revision, we began calculating the CO2 reduction rate based on the “CO2 Emissions Calculation Sheet” using the figures calculated in accordance with the Act on the Improvement of Energy Consumption Performance of Buildings. We have been implementing the revised program since then.

In fiscal 2020, we set CO2 reduction rate of 10% or higher (compared to the standard value under the Act on the Improvement of Energy Consumption Performance of Buildings scheduled to become mandatory in 2020) as our numerical target and implemented it in 86 projects of condominiums designed between April 2020 and March 2021 (63 projects in the Tokyo region and 23 projects in the Kansai region).

Tokyo region Kansai region
CO2 reduction volume (FY2020) 3,600-CO2/year 1,815t-CO2/year
Standard value under Act on the Improvement of Energy Consumption Performance of Buildings CO2 reduction rate 12.5% 11.2%

* The CO2 Emissions Calculation Sheet is a sheet for computing the CO2 reduction rate by converting the standard value and the design value of primary energy consumption of condominium unit areas and communal areas calculated with respect to each project using a Web program in accordance with the Act on the Improvement of Energy Consumption Performance of Buildings into CO2 emissions (t-CO2/year).

Promotion of wood use in construction of condominiums

In recent years, the effective use of domestic forest resources has been drawing attention as part of efforts to build a sustainable social environment, and moreover, the mental relaxation effect of the warmth of wood we have long been familiar with has been re-evaluated.

We have established the Wood Use Promotion Committee and are promoting wood utilization for communal buildings in condominiums as the first step in an effort to use more wood for the main structure of condominiums as appropriate.

In order to meet the diversifying needs including from the projects of our Group, we created the Handbook for Planning and Design of Wooden Communal Buildings to accumulate design and construction know-how on wooden buildings and to add to the menus for proposals for planning and design. This handbook summarizes important points in planning a wooden communal building in the form of a “Planning and Design Flow Chart.” By advancing planning in accordance with the flow and instructions, we are able to plan rationally wooden communal buildings.

Furthermore, for ComRezi Akabane project (to be completed at the end of January 2022, scheduled for delivery at the end of February of the same year), we plan to create wooden common living spaces on the second to fifth floors of its academic residence building. Going forward, we plan to work to develop each element technology with the aim of accumulating multilayered wood construction technology.

“RENAI Yokohama Totsuka: Conceptual CG of the communal building
ComRezi Akabane: Conceptual CG of the common living space of the academic residence building

Energy-saving activities conducted by all companies in the Group

Following the revised Act on Rationalizing Energy Use coming into effect in April 2010, the Haseko Group has been engaging in energy-saving activities at its offices by bringing together all companies in the Group.

Energy Usage and CO2 Emissions in Offices

Based on ISO 14001 and the Group Environment Committee, the Haseko Group is promoting energy-saving efforts in offices centered around the Office Working Group (WG) activities.

In the Oice WG activities, we focus on the amount of energy use for air conditioning, lighting, and oice automation equipment that account for the majority of energy expenditure in our oice buildings, and we engage in power-saving activities systematically by designating a person in charge at each floor of Shiba Head Oice Building and Hiranomachi Building, oices, and branches with the General Affairs Department and Osaka General Affairs Department serving as the secretariat.

In summer and winter, when oice power consumption increases, we set up a special period for power-saving. In addition to responding to the Cool Biz and Warm Biz initiatives oicially promoted by the Ministry of the Environment, we are actively promoting actions such as setting appropriate air conditioning temperatures and turning off lights during lunch breaks in unoccupied areas. We worked to reduce power consumption by aggregating the actual results against our scal 2020 target of “below the scal 2011 actual value per square meter of floor space” to make progress visible every month, in principle, and to inform the sites that failed to achieve the target. Consequently, in scal 2020, we achieved a reduction in energy usage (total usage and energy usage per square meter of floor space) and CO2 emissions compared to the previous year.

Reduction of CO2 by Donating PET Bottle Caps

The Haseko Group donates PET bottle caps as a part of its daily ecological activities. In scal 2020, we collected PET bottle caps equivalent to 1,041 kg from our Offices and construction sites and donated them to the Minato Ward Recycle Business Cooperative.

This contributed to the reduction of CO2 emissions resulting from incinerating PET bottle caps by 3,275 kg.

Registered as a Supporter of “COOL CHOICE” Campaign Promoted by the Ministry of the Environment

The Haseko Group is registered as a supporter of “COOL CHOICE,” a national movement promoted by the Ministry of the Environment.

Within the Group, we disseminate information to make “smart choices” for measures to prevent global warming, with the aim of enabling each employee to choose actions in their daily lives.

Source: The Ministry of the Environment’s COOL CHOICE website

Development of Technology That Reduces Environmental Burdens

Development of “H-BA Concrete,” an Environment-Conscious Concrete

The Global Warming Prevention Plan decided by the Cabinet in accordance with the Paris Agreement calls for expanding the use of blended cement as a way to reduce non-energy-derived CO2 emissions generated by incinerating waste.

Blended cement substitutes concrete admixture such as blast furnace slags and fly ash for a portion of cement, which can reduce CO2 emissions derived from the raw materials of concrete.

We use 225,000 m3/year of typical blended cement called blast furnace cement type-B, mainly as pile concrete for building. To further apply the blended cement, we have developed “H-BA concrete,” which is Haseko’s environment-conscious concrete.H-BA concrete has the same performance as ordinary concrete and at the same time it can reduce CO2 emissions derived from concrete materials by approximately 8.2% to 18.5%. It is produced by mixing ordinary Portland cement with blast furnace cement type-B.

Although its reduction effect of CO2 emissions per cubic meter is limited, it is applicable to all parts of buildings, including ground structures, and therefore it has the advantage of offering versatility as a substitute for ordinary concrete.

The construction of Haseko Technical Center (Tama City, Tokyo, completed in October 2018) achieved to reduce CO2 emissions by approximately 5,800kg by applying about 125m3 of H-BA concrete to exterior porch decks.

In the future, we will also develop an environment-conscious concrete for underground structures, which is highly effective in reducing CO2 emissions. Then we strive for the establishment of an operation system in which appropriate environment-conscious concrete including H-BA concrete is effectively used for the right place of structures.

・There are three types of H-BA concrete (H-BA10, H-BA15, and H-BA20) depending on the blending rate of cement.
・ Amount of CO2 reduced when H-BA concrete is used for 100%, 50%, or 30% of our total concrete use (1,739,000 m3/year)

H-BA concrete application at the Haseko Technical Center

Development of Support Tools for Energy-Saving Performance Calculation

We have developed an energy-saving calculation system which is linked to BIM (Building Information Modeling) data. We make noti cations in accordance with the Act on the Improvement of Energy Consumption Performance of Buildings and examine thermal insulation speci cations using this system. We developed a tool with the aim of further labor saving through automation of calculation as well as visualization of calculation results and launched it at design divisions in the East and West Japan in January 2020. The operation of this tool has enabled a 50% reduction in work hours and a reduction in input errors through automated calculations. We will use these technologies to promote optimal design that meets energy-saving performance requirements.

Biodiversity conservation activities

Conservation Activities

The Haseko Group conducted the following biodiversity conservation activities.
* In fiscal 2020, many activities were suspended due to COVID-19.

Dates Region Description of activities Number of participants
Activities in fiscal 2019
Nov. 30 (Sat.) Kansai Kyosei no Mori tree-planting activities 86 (including 11 children)
Nov. 16 (Sat.) Tokyo TOKYO GREEN SHIP ACTION Kiyose Matsuyama Green Area preservation activities 58 (including 12 children)
Oct. 26 (Sat.) Tokai Fujimae-higata Cleaning Mission in Fall 44 (including 2 children)
Oct. 5 (Sat.) Tokyo Fifth “Haseko no Mori (Tateshina)” afforestation activities 82 (including 13 children)
Jun. 1 (Sat.) Kansai Second “Haseko no Mori (Shirahama)” afforestation activities 75 (including 6 children)
May. 25 (Sat.) Tokyo TOKYO GREEN SHIP ACTION Hachioji Takiyama satoyama preservation activities 56 (including 11 children)
May. 18 (Sat.) Tokai Fujimae-higata Cleaning Mission in Spring 50 (including 5 children)
Activities in fiscal 2020
Oct.31(Sat.) Tokai Fujimae-higata Cleaning Mission in Fall 14 (No child participant)
Nov.7(Sat.) Tokyo TOKYO GREEN SHIP ACTION Hachioji Takiyama satoyama preservation activities 18 (No child participant)