Protecting the precious environment
Energy & CO2

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

Switching to using 100% renewable energy at construction sites

In May 2023, Haseko Corporation successfully switched 100% of electricity used at construction sites to renewable energy sources*. It is planned that by the end of 2025, other Haseko Group companies including Fujikensetsu Co., Ltd., Haseko Reform Inc. and Hosoda Corporation will also switch 100% of electricity used at their construction sites to renewable energy sources.

*This excludes sites pending requests to switch to renewable energy electricity subsequent to the commencement of construction and sites switching to (non-renewable) power company supply before delivery.

Related information

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

Initiatives to reduce CO2 emissions at construction sites

The Haseko Group is promoting the following initiatives at certain sites to reduce CO2 emissions at construction sites. Going forward, we will continue to increase the number of cases of adoption and promotion of these initiatives, while taking the scale and location of project into consideration.

Use of GTL fuel (a GTL sticker)
Adoption of electric forklifts
Adoption of electric backhoe (during testing)

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.

Oji 5-chome by JV including Daiwa House (Tokyo region)

In the construction project of Oji 5-chome by JV including Daiwa House (completion name: Premist Oji Kamiya), approximately 1,295 ㎥ of 9,632 ㎥ of the earth and sand excavated to remove roots from the ground was temporarily stored at the site.

Oji 5-chome by JV including Daiwa House (completion name: Premist Oji Kamiya)

Nishinomiya City Edagawacho PJ New Construction (Kansai region)

In the new construction of “Nishinomiya City Edagawacho PJ (provisional name)” (completion name: Laurel Court Nishinomiya Koshien), part of earth excavated to remove roots from the ground was stored at the site and diverted to backfill soil, by work adjustment. A total of approximately 1,390 ㎥ of it was diverted, resulting in fewer dump trucks to transport it out of the site and a CO2 emissions reduction of about 39 tons.

Nishinomiya City Edagawacho PJ (provisional name) (completion name: Laurel Court Nishinomiya Koshien)

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 PCa for edges of corridors, 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 2022, we achieved a reduction of the use of rainforest wood by 13.5% or equivalent to 176,763m2 in the Tokyo region and by 45.4% or equivalent to 277,880m2 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.

PCa for edges of corridors
ALC method for non-load bearing walls

Use of biomass electric power

In cooperation with an outside power generation company, we have introduced a resource recycling initiative to utilize renewable energy from biomass power generation, which uses waste wooden materials generated at construction sites as part of its fuel, as a temporary power supply at construction sites. In addition, in May 2023 Haseko Corporation completed the transition to using renewable energy sources for 100% of electricity* used at construction sites.

*This excludes sites pending requests to switch to renewable energy electricity subsequent to the commencement of construction and sites switching to (non-renewable) power company supply before delivery.

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.

Signboard at the site adopting biomass power generation

Participation in the biomass power generation business

Haseko Corporation participates in biomass power generation business with the goal of achieving carbon neutrality.
We participate in a woody biomass power generation business in Ikoma city in Nara undertaken by TJ Group Holdings Inc. Scrap wood and unused timber from the Kinki region will be used as fuel for generating power in the business, which makes it possible to supply locally produced and locally consumed electricity, including fuel for power generation, for users in the Kinki region. (Commercial operation is scheduled to start in April 2025.)
In Matsusaka City in Mie, we participate in a decarbonized power source development business undertaken by Power Aid Mie that uses hybrid fuel of only NON-FIT wood and manufacturing byproducts. In this business, waste recycled wood chips and plastic chips generated from various construction sites will be repurposed as fuel, leading to the reduction of the administrative burden of waste disposal operation and the contribution to the creation of a local circular resource and energy economy. (Commercial operation is scheduled to start in January 2025.)
We will continue our efforts to contribute to creating carbon zero cities through initiatives such as biomass power generation business.

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 2022, 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 100 projects of condominiums designed between April 2022 and March 2023 (76 projects in the Tokyo region and 24 projects in the Kansai region).

Tokyo region Kansai region
CO2 reduction volume (FY2022) 8,375t-CO2/year 2,862t-CO2/year
Standard value under Act on the
Improvement of Energy Consumption Performance of Buildings
CO2 reduction rate 19.8% 22.9%

* 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.
“ComRezi Akabane” utilizes wood for the common living spaces on the second to fifth floors of the student residence building. “BRANSIESTA Urayasu” was our first completed condominium featuring wooden construction in exclusive areas, with the top floor residential units (14 in total) being constructed from wood.
The Haseko Group has worked on research and development of wooden architecture since 2014, and we have completed 14 projects and have 9 projects currently under construction. (as of August 2023)
A project featuring fire-resistant wooden structure on the its top four floors, “(provisional name) Meguro-ku Chuocho 1-chome Plan” is scheduled to be completed in March 2025. We will continue our efforts to challenge the adoption of wood in high-rise buildings and expand its application from the current rental condominium to include for-sale condominium development.
We will continue to promote the use of wood in construction with the goal of achieving carbon neutrality in 2050.

Structural diagram of top floor
Photograph of top floor unit interior

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

Haseko Group is promoting energy saving in offices, centering on the activities by the “Response to Climate Change Office Working Group (WG).”

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

In summer and winter, when office power consumption increases, we set up a special period for power-saving. In addition to responding to the Cool Biz and Warm Biz initiatives, we are actively promoting actions such as setting appropriate air conditioning temperatures and turning off lights during lunch breaks and in unoccupied areas. We have obtained SBT certification in FY2022 and calculated CO2 emissions by accumulating monthly total energy consumption of each company. And we have compiled quarterly accumulation to visualize our progress and made an effort to reduce energy consumption volume. As a result, in fiscal 2022, we achieved a reduction of 20,178 tons CO2, or 1.0% from fiscal 2021.

Reduction of CO2 by Donating PET Bottle Caps

The Haseko Group donates PET bottle caps as a part of its daily ecological activities. In fiscal 2022, we collected PET bottle caps equivalent to 593 kg from our Offices and construction sites and donated them to the Japan Committee, Vaccines for the World’s Children (JCV).

This contributed to the reduction of CO2 emissions resulting from incinerating PET bottle caps by 1,864 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 (Japanese Only)

Green procurement initiatives

Initiatives to select materials with smaller environmental footprint is called green procurement. As part of our green procurement initiatives, we investigated 14 green procurement materials for FY2022 and counted their quantity.

Going forward, we will review and add green procurement materials as necessary in consideration of green procurement results, social trends and other factors.

Item Unit FY2018 FY2019 FY2020 FY2021 FY2022
Steel for electric furnace
(reinforcing steel)
1,000t 228 198 187 169 195
Blast furnace cement and
freshly-mixed concrete
1,000m3 225 210 208 225 208
Recycled tiles 1,000m2 356 329 226 220 246
Recycled plasterboards 1,000m2 4,765 4,793 4,537 4,900 4,828
Particle boards
(double flooring)
1,000m2 255 247 267 378 272
Styrene materials
(wall-backing packing)
m3 419 366 377 325 1,005
Water-saving toilet bowl 1,000units 20 15 15 16 17
Rooftop and wall greening 1,000m2 11 9 1 9 6
Permeable paving 1,000m2 26 23 30 21 23
SUS piping (water supply piping in communal areas) t 53 29 21 31 47
LED lighting equipment 1,000units 194 304 176
Long vinyl sheets 1,000m2 383 369 293 329 311
Extruded polystyrene foam 1,000m3 4 4 4 34 4
CFC-free urethane foam 1,000m2 389 720 890 892 867

* Data for extruded CFC-free urethane foam since FY2018, and LED lighting equipment since FY2022.

Blast furnace slag cement type B

Blast furnace slag cement type B, which is superior against cracks and in terms of chemical resistance, is mainly adopted in concrete piles. CO2 generated during cement production is the largest in volume during the manufacturing process of clinker, an interim product of cement. The production of blast furnace slag cement involves mixing large volumes of blast furnace slag fine powder into normal cement, which leads to a much lower composition ratio of clinker than in normal cement, and in turn, reduction of CO2 emissions.

In fiscal 2022, adoption of blast furnace slag cement type B was 220,347 m3, resulting in the reduction of CO2 emissions by approx. 24,899.

Concrete piling installation

Development of Technology That Reduces Environmental Burdens

Development of “H-BA Concrete,” an environment-conscious concrete

Produced by blending ordinary Portland cement and blast furnace cement type-B, H-BA concrete is so versatile that it can replace conventional concrete. It is eco-conscious concrete that reduces CO2 emissions derived from concrete materials by approximately 20%.
To date, it has been used in projects including a part of the common-use areas of “Renai Yokohama Totsuka” (Totsuka-ku, Yokohama City, Kanagawa; total 439 units) and the entirety of the “Gakuen Higashimachi Project” (foundations and above-ground framework), a rental condominium building targeting students (Nishi-ku, Kobe City, Hyogo; total 120 units). In August 2022, H-BA concrete obtained the “Special Evaluation Method Certification*2,” which is recognized as an alternative evaluation method to methods that comply with the “Evaluation Method Criteria*1,” from the Ministry of Land, Infrastructure, Transport and Tourism. This certification allows it to be used in for-sale condominiums that use dwelling performance indications.
In 2021, we established the Haseko Group’s Climate Change Response Policy: “HASEKO ZERO-Emission”, and we are working to popularize “H-BA concrete” to reduce greenhouse gas (CO2) emissions. Based on the Special Evaluation Method Certification, “H-BA concrete” has been adopted for the first time as sale condominiums for the entirety of the above-ground framework in the “Kamiikedai Project” (Ota-ku, Tokyo; total 42 units) in the Tokyo area, and the “Renai Esaka Enokicho” (Suita City, Osaka; total 149 units) in the Kansai area. We will continue to utilize H-BA concrete in the Group’s projects. In addition to Group business projects, we will work to popularize H-BA concrete in the projects of other companies to promote the reduction of greenhouse gas (CO2) emissions across the entire supply chain.

*1 Evaluation Method Criteria: Criteria for methods of evaluating housing performance to be indicated in accordance with the Japan Housing Performance Indication Standards stipulated in the Housing Quality Assurance Act.
*2 Special evaluation method certification: Certification method approved on an individual basis by the Minister of Land, Infrastructure, Transport and Tourism for new materials and construction methods (e.g., structural safety, reduced deterioration, thermal environment, sound environment) that cannot be evaluated in accordance with evaluation method criteria stipulated in the Housing Quality Assurance Act.

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 notifications in accordance with the Act on the Improvement of Energy Consumption Performance of Buildings and examine thermal insulation specifications 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.

Obtained SBT initiative approval

In May 2022, among the greenhouse gas (CO2) (*1) reduction targets set by the Haseko Group, the fiscal 2030 reduction targets were approved as science-based targets by the SBT (Science Based Targets) initiative (*2).

(*1) CO2 is the principal greenhouse gas in the world and accounts for the majority of the Haseko Group’s emissions. (*2) It was jointly established in 2015 by CDP, the United Nations Global Compact, the World Resources Institute (WRI), and the World Wildlife Fund for Nature (WWF) to encourage companies to set science-based greenhouse gas emission reduction targets toward the goals of the Paris Agreement “limiting global temperature rise to well-below 2°C above pre-industrial levels and pursuing efforts to limit warming to 1.5°C.”

The Haseko Group’s greenhouse gas emission reduction targets approved by the SBT initiative

We have set the following greenhouse gas emission reduction targets with fiscal 2020 as the base year.

(*3) Scope 1: Direct emissions by the business itself
(*4) Scope 2: Indirect emissions associated with consumption of electricity, heat or steam purchased from outside
(*5) Scope 3: Indirect emission other than Scope 1 or 2 (supply chain emissions related to the business’s activities)

Biodiversity conservation activities

Conservation Activities

The Haseko Group conducted the following biodiversity conservation activities.
*In FY2020 and FY2021, many activities were suspended due to COVID-19.

Dates Region Description of activities Number of participants
Activities in fiscal 2021
Nov.27(Sat.) Tokyo ”Ikimono Hakken in Tamatsurumaki”(Biodiversity Seminar) 15(including9children)
Activities in fiscal 2022
May.21(Sat.) Tokyo TOKYO GREEN SHIP ACTION Hachioji Takiyama satoyama preservation activities 27(No child participant)
May.28(Sat.) Tokai Fujimae-higata Cleaning Mission in Spring 11(No child participant)
Jun.4(Sat.) Kansai Third“Haseko no Mori(Shirahama)”afforestation activities 18(No child participant)
Jun.11(Sat.) Tokyo ”Ikimono Hakken in Tamatsurumaki”(Biodiversity Seminar) 20(including11children)
Oct.1(Sat.) Tokyo TOKYO GREEN SHIP ACTION Kiyose Matsuyama Green Area preservation activities 22(No child participant)
Oct.15(Sat.) Tokyo Sixth “Haseko no Mori(Tateshina)”afforestation activities 29(No child participant)
Oct.22(Sat.) Tokai Fujimae-higata Cleaning Mission in Fall 16(No child participant)
Nov.12(Sat.) Kansai Kyosei no Mori tree-planting activities 25(No child participant)
Nov.22(Sat.) Tokyo “Ikimono Hakken in Tamatsurumaki”(Biodiversity Seminar) 19(including10children)
Activities in fiscal 2023
May.22(Sat.) Tokai Fujimae-higata Cleaning Mission in Spring 14(No child participant)
May.27(Sat.) Kansai Fourth“Haseko no Mori(Shirahama)”afforestation activities 47(including6children)
Jun.10(Sat.) Tokyo “Ikimono Hakken in Tamatsurumaki”(Biodiversity Seminar) 25(including13children)