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Initiatives to Protect the Environment

Green ICT Our Action

Through our business activities, we work to protect the environment in three focus areas.


Realizing a Low-Carbon Future
Implementing Closed-Loop Recycling
Planning a Future of Natural Harmony

Realizing a Low-Carbon Future

The need to realize a low-carbon society is becoming an increasingly urgent challenge that extends well beyond national and organizational boundaries. Addressing this challenge will help ensure the prosperity of humankind as well as every living organism on the planet, while meeting certain imperatives including goals 13, ”Climate Action,″ and seven, ”Affordable and Clean Energy,″ of the UN’s SDGs. The NTT Communications Group is taking a diversified approach in order to address this issue. Among a host of initiatives, we are installing highly efficient equipment with better energy-saving features, providing excellent services with a low carbon footprint, and undertaking environmental contribution activities.

Goal 7:Ensure access to affordable, reliable, sustainable and modern energy for all
Goal 13: Take urgent action to combat climate change and its impacts

Company Initiatives

Making Air-Conditioning at Data Conters More Efficient

An important theme in reducing power consumption at data centers is making air-conditioning more efficient. From the data center design stage, we are bringing in the following wide-ranging innovations.

(1)Innovation in Buildings

To increase the heat insulation of buildings we are working to improve efficiency from the structural aspect, such as by adopting innovations that utilize thick concrete panels and insulation materials and by reducing the window surface area. With regard to air-conditioning, we are absorbing heat such as that generated by the IT equipment in rooms, liquefying the refrigerant cooled by the convection force of heated refrigerant rising as gas and by outside air, using the downward convection force from the difference in height of the equipment, and taking advantage of a natural refrigerant circulation system to use power sources and pumps as little as possible. These technologies are used in combination at the Tokyo No. 5 Data Center and are bringing about a reduction in CO2 emissions.


(2)Innovation in Server Rooms

Depending on the loucation, temperature differences occur in a server room as the amount of heat generated in a server room depends on the various types of server installed. While effectively eliminating this, efficient cooling is important in curbing CO2 emissions. To achieve this at our data centers we are implementing finely tuned air-conditioning management innovations. For example, we have introduced the SmartDASH*1 automatic air-conditioning control system, installed the Aisle Capping*2 airflow control solution, which increases the rectifying effect of the cool air, and the Blank Panel system, which is capable of efficiently cooling servers by utilizing the cool air trapped in the spaces between the server racks.
Since fiscal 2012, we have accelerated our efforts to create server rooms with total solutions entailing both hardware and software for air conditioning management. As only a leading ICT company can, NTT Communications promotes energy-saving solutions throughout the Group by proactively implementing these solutions in its regional data centers and telecommunications buildings.


*1 Depending on the country and region, SmartDASH is a registered trademark or trademark of Vigilent Corporation.

*2 Aisle Capping is a registered trademark of NTT Facilities, Inc.

(3)Deployment of an Outside Air Cooling System

Tokyo No. 6 Data Center:High-efficiency modular chillers

Tokyo No. 6 Data Center:
High-efficiency modular chillers

An outside air cooling system draws outside air into a building during winter, spring, and autumn when the air is cooler outdoors than indoors.
Rows of servers, networking equipment, and other ICT equipment in data centers (DCs) generate significant heat, and the outside air cooling system effectively cools the DCs using much less energy.
We adopted an indirect evaporative cooling system that uses outside air throughout our new DC in Musashino City, Tokyo. Also, we introduced cutting-edge technology for total management of airflow, including air intake and exhaust from emergency power generators. These measures are expected to reduce annual energy usage by about 60% compared to an average air conditioning system. We will continue incorporating advanced equipment and technologies with the aim of aggressively reducing our DC’s carbon footprint.


(4)Complete Airflow Management

The arrangement of hot aisles and cold aisles as pathways for hot and cold airflow is an issue that can significantly impact the efficiency of a building's air conditioning system. To realize optimal airflow management, we have innovated literally from the ground up by redesigning the floors of our data centers. These innovations include panels that vent chilled air circulated under a false floor, horizontal air conditioning that blows air from the walls into the room, large fans on the walls near the ceiling to efficiently move hot air out of the room, and an exhaust chamber. By combining these innovations with fresh air air-conditioning systems, we aim to create optimal airflow throughout the entire building.


Airflow management at the Tokyo No. 6 Data Center

Using our Data Center Know-How to Control Airflow: ”Airflow Improvement″

We are applying the knowledge we have gained building low-carbon data centers to our telecommunications facilities. For example, we have conducted "airflow improvement" initiatives since fiscal 2011 in the communications equipment rooms of our communications buildings in each region.


(1)Diffuser (wind direction panel) installation
Diffusers are installed to direct exhaust heat from the rear of ICT equipment upward and away from other devices.

Diffuser installation

(2)Screen Installation
Screens are installed to ensure that the exhaust heat from various equipment does not flow onto other devices.

Screen Installation

(3)Floor panel improvement
Steps taken to confirm heat accumulation and points of excessive cooling and improvements made through adjustments using retractable fins, curing tape and other items to control underfloor air flow.

Floor panel improvement

(4)Drawstring bag application
Drawstring bags are applied to prevent the leakage of cold air.

Drawstring bag application


We expect these initiatives to have a greater impact as we gradually expand these measures to other facilities around the world, and apply this expertise to energy management for office buildings.

Efficient Power Supply by Leading-Edge Technologies

Requiring large numbers of AC/DC converters when supplying power to equipment, the currently widely used alternating current (AC) power supply suffers problems from the efficiency standpoint, such as heat release and power loss. The low-voltage direct current (DC) power supply has therefore been used in the past, but this has raised many issues from the building work and cost aspects as DC requires thick cabling to supply power to high-capacity IT equipment. The high-voltage direct current (HVDC) system is attracting attention as a technology that can rapidly resolve these issues. By introducing this system, positive steps are being taken to realize such improvements as a 20% reduction in power consumption and a 40% improvement in space efficiency.


Improving Environmental Performance Globally

The NTT Communications Group has data centers and telecommunications facilities located throughout the world, and we proactively transfer our home-grown technologies and know-how for improving environmental performance to these facilities around the world. As of the end of fiscal 2013, the number of facilities using SmartDASH stood at 28 locations, and the number of data centers with Leadership in Energy and Environmental Design (LEED) certification, a world standard for green buildings, was 10 locations.
* An environmental performance rating system for buildings created by the U.S. Green Building Council.

Case (1)
Energy Conservation at Hong Kong Financial Data Centre (FDC) The Hong Kong FDC obtained LEED Gold certification in fiscal 2013 in recognition of its deployment of advanced environmental technologies and highly efficient equipment. With the aim of improving as much as possible the cooling efficiency of facilities and equipment, which affects environmental performance considerably, the Hong Kong FDC features inverter-controlled fans in its air conditioning systems, cold-aisle containment to separate cold air from the heat given off by servers, as well as double-floor, double-ceiling air conditioning chambers. The power source for the operations center features a fuel cell-based UPS (Uniterruptible Power Supply), which helps our customers achieve their energy reduction targets through substantial energy savings.

picture Air conditioning system that blows cool air from walls

Air conditioning system
that blows cool air from walls

Case (2)
Energy Conservation at the U.K. Data Center In June 2012, NTT Communications acquired U.K.-based Gyron Internet Ltd., a provider of cloud computing services in Europe. We have been working since then to conserve the energy used by the data center by installing the latest environmental technologies. Specifically, we have implemented an efficient air conditioning system for the entire data center, which offers world-class energy-saving performance and high reliability, by using indirect outdoor air cooling and air conditioning systems that blow cool air from walls using airflow optimization technology.

Use of Clean Energy

NTT Communications has been installing solar panels mainly at its data centers in the Tokyo metropolitan area, and the electricity generated powers the lights in common areas and more. In fiscal 2019, the company generated 308,393 kWh of solar power, which converts to 142,478 kg-CO2, equivalent to the amount of CO2 absorbed by 10,177 Japanese cedar trees in a year.

The NTT Communications Group intends to further reduce its environmental impact through the introduction of renewable energy toward at least 30% of its total consumption by fiscal 2030.

Fiscal 2019

Saving Electricity in Offices

In addition to installing environmentally friendly equipment, the NTT Communications Group is saving electricity in its offices. For instance, we adjust the temperature settings of air conditioners while considering workplace environments and operating efficiency, optimize the number of lights, modify the degree of illumination, and encourage employees to switch off office automation equipment when not in use and select energy saving mode as the default setting for PCs to save electricity year-round.
Moreover, NTT Communications relocated to Otemachi Place, its new head office building, in January 2019, where it has significantly saved energy compared to its former site at the Hibiya Building. These savings are the result of such actions as adopting an efficient district heating and cooling system and using motion sensors to control lighting.
In response to COVID-19, we fully embraced the ”Remote Work Native″ initiative as a new workstyle starting in March 2020. Because of this and other measures, our power consumption at three main buildings (Otemachi Place, Shiodome Building, and Tamachi Granpark Tower) for the first quarter of fiscal 2020 (combined total for April to June) declined by 45.5% from fiscal 2010, which was prior to the Great East Japan Earthquake*, and by 18.6% from fiscal 2019.
Initiatives using ICT include measures to save electricity in our offices through the Office Database Visualization Website on our intranet, which aggregates and visualizes environmental impact data by floor. NTT Communications plans to decrease its environmental impact by reducing the electricity used to power its servers through integration by migrating internal systems to ICT infrastructure on a private cloud that leverages server virtualization.


*Power consumption data prior to the Great East Japan Earthquake is the combined sum of the Hibiya Building, Shiodome Building, and Tamachi Granpark Tower.


Initiatives for Society

Enterprise Cloud : Streamlined Integration of ICT Infrastructure

As companies accelerate their expansion overseas through mergers and acquisitions, it is becoming all the more necessary to streamline and integrate their ICT infrastructure on a global scale. From an environmental standpoint as well, companies are dealing with the issue of reducing the wasteful use of resources, especially investments in redundant equipment throughout the corporate group. Enterprise Cloud is a world-first cloud-based service for corporations that uses virtual network technologies between data centers in addition to within data centers. Utilizing cutting-edge virtualization technologies, including virtual servers and virtual networks, Enterprise Cloud integrates ICT systems that companies had deployed and operated differently in each region and office. This service makes it possible to deploy integrated ICT infrastructure that cuts out the wasteful allocation of equipment and personnel throughout corporate groups.


Recent installations have proven the major benefits of this service. When virtual servers are deployed through the service instead of traditional physical servers and storage devices on the customer's premises, the number of physical servers in operation are reduced, thereby cutting CO2 emissions by 97 t-CO2 annually (about 74%) in the case of a small or medium-sized company.

Data Centers Consolidate Corporate Customer's Servers and Conserve Energy

Arcstar Universal One Offers an Innovative Way to Work on Mobile Devices

Arcstar Universal One is a virtual private network (VPN) service we offer for corporations that allows employees to securely access corporate systems over high-speed communications from locations outside their company. As a part of our Arcstar Universal One service, we also provide a high-speed data communications environment for mobile devices to connect securely to VPNs. This service expands the range of possibilities for working outside the office, while reducing the need to move in order to work in the office.


Reducing Environmental Impact Using the Arcstar IP Voice Service

IP telephone services that help curtail call charges are also becoming increasingly popular with the widespread use of the Internet. As a high-quality IP telephone service geared toward the corporate sector, Arcstar IP Voice not only contributes to lower call charges, but is also environmentally friendly.

For example, positive steps can be taken to cutback the amount of network infrastructure CO2 emissions by integrating voice and data communications into a single network. Moreover, and in line with network integration, the opportunity exists to reduce electricity consumption through the upgrading of ICT equipment. Studies have shown that the introduction of Arcstar IP Voice has contributed to an annual reduction of 30% in the amount of CO2 emissions compared with such conventional means as the use of ISDN networks for voice calls and VPN networks for data communication

The graph depicts respective percentages with the amount of CO2 emissions using conventional means set at 100%

Making Working at Home Easy and Simple with Enterprise DaaS

Implementing Closed-Loop Recycling

Goal 12, ”Responsible Consumption and Production,″ of the UN’s SDGs highlights the importance of initiatives aimed promoting the proper use of limited resources as well as the need to address such key issues as pollution and waste. At each and every workplace including offices, data centers, and communication facilities, we are advancing measures that stand at the forefront of efforts designed to realize a recycling-based society.


Goal 12: Ensure sustainable consumption and production patterns

Company Initiatives

Recycling Old Communications Equipment

To realize a closed-loop society, corporations are expected to recycle as much as possible in accordance with the nature of their operations. As a global ICT company, NTT Communications has for a long time recycled its old communications equipment.
Our own efforts are obviously important in recycling, and initiatives across our entire supply chain are also paramount. Waste from communications facilities is separated and reused as much as possible as a companywide policy. NTT Communications selects its waste management contractors based on their qualifications with a heavy emphasis on recycling ratios.
Thanks to these initiatives, the recycling ratio for old communications equipment remained at the high level of 99.99% in fiscal 2018.

Adopting Rotary UPS

picture Rotary UPS

Rotary UPS

Data centers have to operate stably even in the event of a power failure. That is why uninterruptible power supply (UPS) systems are widely being installed as a backup power source. Since many batteries are required for conventional UPS systems, problems have arisen with the generation of waste materials that include lead when UPS equipment has been replaced. Our attention is now focused on rotary UPS systems, which integrate generators and a UPS, thus removing the need for batteries. By broadly adopting a rotary UPS for our new data centers, we aim to curb the amount of harmful substances that arise from data centers. Rotary UPS systems have been used at our Tokyo No. 6 Data Center since it opened in fiscal 2013. The systems represent one facet of our next-generation data centers, which are highly reliable, produce clean energy, and have been praised by financial institutions and many other organizations.

Planning a Future of Co-existing with Nature

In addition to measuring the state of the earth’s health, biodiversity brings a host of benefits to humankind. Goals 14 and 15 of the UN’s SDGs strongly advocate the need to conserve the biodiversity of life below the water and on land as the means to realize a society that coexists with nature. In order to pass on a world that is brimming with diversity, it is vital that we reflect on ourselves as a matter of course and engage in a wide range of activities. This includes putting forward services that help conserve biodiversity while promoting social awareness.

Goal 14: Conserve and sustainably use the oceans, seas and marine resources
Goal 15: Sustainably manage forests, combat desertification, halt and reverse land degradation, halt biodiversity loss

Company Initiatives

Guidelines for Facilities that Show Regard for Biodiversity

For facilities that show regard for biodiversity, we are establishing guidelines to serve as policies applicable to all our facilities, not solely to data centers. From the selection of the site to the construction and demolition of a facility, the guidelines list items that should be emphasized from the biodiversity point of view; we rigorously adhere to these guidelines. We want to contribute to the creation of a global sustainable society by sharing these guidelines throughout the NTT Communications Group.

Examples of Emphasized Items

It is widely known that planting rooftop gardens and installing green walls contribute to curbing a building's heat retaining effects and, by extension, CO2emissions. At the same time, however, these measures have other effects, such as the absorption of pollutants in the atmosphere by plants. In recent years, greening measures have also been attracting attention from the point of view of creating towns that are in harmony with nature. As part of our efforts to protect the environment through our business activities, we are actively incorporating greening measures at each one of our data centers.


Installation of green walls at the Tokyo No.5 Data Center

As a data center in the Tokyo metropolitan area, uppermost in our minds is the reduction of CO2 emissions and lush scenery that is in harmony with the area.

Participating in Urban Tree-Planting Promotion Business Activities

spring-summer zoneautumn-winter zone

spring-summer zone autumn-winter zone

NTT Communications unveiled its 6th and largest data center in Tokyo in April 2013. Under the auspices of the Tokyo Metropolitan Park Association's Municipal Tree-Planting Fund, the Center is actively promoting tree-planting activities deeply rooted in the local community. As a part of these endeavors, trees have been planted within the Center's grounds in two distinct spring/summer and autumn/winter zones. As a result, visitors can enjoy the beauty and pleasure of seasonal flowers all year round. Complementing this initiative, steps have been taken to conduct wind environment simulations. By planting such vegetation as evergreen trees along the southwest corner, which bears the full brunt of wind activity, every effort is being made to ensure harmony with the surrounding environment.

Allowing Environmental Preservation Activities at Our Telecommunications Facilities

Wireless relay stations, the backbone of data communication networks, are often located in the midst of abundant natural surroundings, and we pay due consideration to biodiversity in operating these facilities. For example, every year since September 2012, the Amami Ornithologists’ Club, an NPO, has hosted events for observing the migration of Chinese sparrow hawks on the premises of our wireless relay station in Amami City, Kagoshima Prefecture. Although the stations are normally off limits because of their vital importance to telecommunications infrastructure, we grant an entry permit to the club for these annual events in response to a request that explained how well suited this particular area is for monitoring the ecosystem.
The Chinese sparrow hawk is a small bird of prey that breeds in the Korean Peninsula and mainland China and passes through Japan in its fall migration to winter in Southeast Asia. The Amami Ornithologists’ Club has conducted three observations and on one occasion confirmed a large flock of more than 2,000 birds. Hawks are at the top of the food chain and viewed as a keystone species for gauging the health of the entire ecosystem based on the size of the migratory flock. We hope to continue cooperating with activities that contribute to the conservation of ecosystems.

Chiyoda Ward Cleanup

Participating in local cleanup campaigns is both our responsibility as a member of the community and an opportunity to gain firsthand knowledge of environmental issues. That is why we take part in cleanups around all our business locations. Employees and partners of NTT Communications working at the head office take the lead in the Cleanup Chiyoda Ward Campaign, held early in the morning before regular working hours in June and November every year.

While the event was canceled in fiscal 2020 to prevent the spread of COVID-19, we intend to continue it at some point.

Cleanup Campaign in Fiscal 2019
Cleanup Campaign in Fiscal 2019

SDG Photo Contest

NTT Communications believes that everyone and every organization on this planet—both individuals and companies—need to be aware of the importance of biodiversity and take action to preserve it. With this in mind, we have held the Biodiversity Photo Contest: Living with Nature since fiscal 2016. In fiscal 2020, we renamed it the SDG Photo Contest and provided opportunities for employees as well as their families and acquaintances to come together and think about how to create a sustainable society and preserve biodiversity.

The most recent contest had three categories: living things, natural landscapes, and coexisting with nature, and Group employees submitted about 200 photos. Some staff who participated remarked that taking photos for the contest and appreciating the works of others helped them to feel a deeper respect for nature and more closely connected to biodiversity. It also renewed their awareness of what must be done to pass on nature’s beauty to future generations.

The photos will appear in our corporate calendar, seen by Group employees and staff at partner companies. As for the contest, we will continue to hold it to raise employee awareness of environmental protection.

President’s Award
President’s Award
Special Recognition Award
Special Recognition Award
5th SDG Photo Contest

Excellence Award Photos

Excellence Award Photos
4nd Biodiversity Photo Contest
President’s Award

President’s Award

CSR Committee Chairman’s Award

CSR Committee Chairman’s Award

Special Recognition Award

Special Recognition Award

Excellence Award Photos

excellence award photos
3nd Biodiversity Photo Contest
President’s Award

President’s Award

CSR Committee Chairman’s Award

CSR Committee Chairman’s Award

Special Recognition Award

Special Recognition Award

Excellence Award Photos

excellence award photos
2nd Biodiversity Photo Contest
President’s Award

President’s Award

CSR Committee Chairman’s Award

CSR Committee Chairman’s Award

Special Recognition Award

Special Recognition Award

Excellence Award Photos

excellence award photos
1st Biodiversity Photo Contest

Grand Prize Photos

Natural landscape category winner

Natural landscape category winner

Living things category winner

Living things category winner

Coexisting with nature category winner

Coexisting with nature category winner

Special Prize Photos

President's Award

President’s Award

CSR Committee Chairman's Award

CSR Committee Chairman’s Award

ShiningArcs Award

ShiningArcs Award

Initiatives for Society

Coastal Area Cleanup Activities

We have been cleaning the beaches around Fujisawa City, Kanagawa Prefecture, since 2017, amid growing international concern over waste plastic, including environmental pollution caused by microplastics. Although coastal cleanups were canceled in 2020 due to the spread of Covid-19, we intend to resume the activity once the pandemic subsides. Meanwhile, NTT Communications’ Shining Arcs rugby team participated in the LEADS TO THE OCEAN project in August 2020, the aim of which is to reduce the volume of waste that ends up in the ocean by keeping towns clean. Launched in 2015, the project is a joint effort between the Nippon Foundation, which has been engaged in marine and social issues for over half a century, and the non-profit organization Umisakura, which has been organizing the Enoshima beach cleanup since 2005. The Shining Arcs is the first rugby team to participate in the project.

Coastal Area Cleanup Activities
Coastal Area Cleanup Activities
Coastal Area Cleanup Activities

Providing Information on Environmental Protection Activities through the "goo Green label"

goo screen capture

NTT Resonant Inc. has donated a total of 58.1 million yen in revenue earned over roughly 12 years from operating the ”goo Green Label″ web portal to support the work of NPOs protecting the natural environment. The company will continue to engage in activities that link conservation activities with use of the Internet for accessing news and running keyword searches on PCs and smartphones. The goo Green Label communicates information about nature and the environment and provides content that makes learning enjoyable, such as proficiency exams and quizzes to stimulate interest in nature and the environment.
As its name suggests, NTT Resonant focuses on educational activities for promoting biodiversity in a way that ”resonates″ with the NTT Group and the general public.


goo Green Label: (in Japanese)

"Mimawari Rakutaro" Wild Animal Trap and Notification System

goo screen capture

In rural areas of Japan, wild boars, deer and other animals causing damage to agriculture and forests have become a serious problem. One way of dealing with this is to set up traps to catch wild animals. However, safely and efficiently using these traps is an issue in rural areas where the elderly are growing in number.

NTT PC Communications has been helping to solve this problem by developing "Mimawari Rakutaro," a wild animal trap equipped with a monitoring and notification system, as a part of its "IoT services" that utilize data sent by sensors out in the field. The system uses the communications network of NTT DoCoMo to automatically send notification emails to designated mobile devices and computers when the trap door is activated and closes.

In the past, someone had to do patrols to see if a wild animal had been caught. "Mimawari Rakutaro," however, helps to reduce the daily workload, and traps equipped with cameras can send pictures of what is inside so that responders can quickly help anything other than a destructive animal that has been mistakenly caught. Moreover, the zones available to set up the product have been broadened so that they now extend beyond mobile phone service areas, owing to its configuration, which consists of a master phone and extensions connected using LPWA (LoRa) communications technology. Since its release in July 2011, "Mimawari Rakutaro" has been put to use by more than fifty local governments and three forest management organizations around Japan, spreading the use of ICT.

We will continue to help with the preservation of our natural environment through efforts like these.

Mimawari Rakutaro

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