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Social Challenge 1
Moving toward a decarbonized society


Why it matters

The NTT Group views one of its core roles as helping to resolve environmental issues that society faces, and is continuing its existing activities aimed at reducing greenhouse gas emissions. There are increasingly high hopes that the ICT sector will be able to help resolve environmental issues, and this has been outlined in the Paris Agreement. The NTT Group remains committed to measures that utilize ICT services and cutting-edge technology to reduce greenhouse gas emissions.

What can be accomplished

The NTT Group is committed to initiatives that reduce greenhouse gas emissions throughout its business activities and society as a whole, by rolling out IOWN technology and increasing development and use of renewable energy sources.

Future vision

The NTT Group is pushing ahead with research and development aimed at curbing climate change, encouraging employees to take part in nature conservation activities, increasing awareness inside and outside the group of its activities that help improve the environment, and many other activities to contribute to a reduction in greenhouse gas emissions throughout society as a whole.

Basic Policy and Action Guidelines

Basic Policy
The NTT Group is committed to achieving a new level of prosperity where humanity can coexist and preserve nature for generations to come. To this end, we will work to balance solving ecological problems and improving economic development by reducing the environmental impact of our business activities and creating new technologies and innovations.
Action Guidelines
  1. 1. Reducing greenhouse gas emissions
    The NTT Group is committed to initiatives that reduce greenhouse gas emissions throughout its business activities and society as a whole, by rolling out
  2. 2. A commitment to resource recycling
    We will shift from a one-time use consumption-oriented company to a recycling-oriented one. We will promote the effective use of resources throughout the entire life cycle of products and systems, from procurement to use and disposal.
  3. 3. Conserving ecosystems
    Through our business and employee activities, we will promote initiatives related to conserving ecosystems within nature.
  4. 4. Compliance with laws and regulations and fulfillment of social responsibilities
    We comply with the laws and regulations related to environmental issues in each country and region, and act with high ethical standards.
  5. 5. Establishing and maintaining environmental management systems
    We will establish the Green Innovation Committee chaired by the Representative Director and Senior Executive Vice President, and discuss basic strategies concerning environmental issues, the status of implementation of activities, and information disclosure, and implement relevant initiatives.
  6. 6. Stakeholder engagement
    We will engage with stakeholders throughout our entire value chain to help resolve environmental issues.

Disseminating Environmental Activities Policies and Measures among Employees

NTT Group conducts environmental education to disseminate NTT Group policies and measures among employees and develop a shared understanding of Group-wide activities for promoting environmental protection. In fiscal 2022, we also provided training related to the Group's environmental activities for all employees, such as group training and e-learning. The NTT Environmental Protection Office organizes environmental education for staff in charge of environmental issues at each Group company and has been holding study sessions every year since fiscal 2001. Along with lectures for disseminating our environmental policies and sharing outstanding issues, we invite outside lecturers to speak on recent topics. These study sessions are intended for the NTT Group throughout Japan and are therefore offered via a teleconferencing system so that staff in remote areas can attend and ask questions through twoway connections. This paperless approach is also another way the NTT Group is helping to reduce greenhouse gas emissions resulting from holding meetings.

In fiscal 2022, we invited experts on environmental management and CSR to explain the SDGs and ESG and to speak about environmental management. Furthermore, related staff in Group companies introduced their environmental initiatives with the aim of promoting environmental activities at each Group company.

Compliance with Environmental Laws and Regulations

The NTT Group complies with laws and regulations related to the environment and works to reduce its impacts on the environment. We have established a mechanism that can deal with cases of legal violations on a Group-wide basis by reporting to the Global Environmental Protection Promotion Committee. There were no legal violations nor payments of penalties in fiscal 2022, following the same result for fiscal 2021. As part of its environmental management measures, the Group also tracks the number of complaints related to the environment for each fiscal year.

In fiscal 2022, no complaints related to environmental impact were submitted, handled or resolved through our systems for dealing with complaints. Going forward, we will maintain compliance with existing laws and regulations as well as set up a working group on environmental laws and regulations to help step up our preparations for complying with laws and regulations under review or scheduled to take effect.

Business Activity 1
Promoting energy conservation

Our commitment

We are working to improve the energy efficiency of our business. (EP100, environmental target 2030) *1

Our objective

Two times

2025: Power efficiency (compared to FY2017)


2030: Power efficiency (compared to FY2013)

Background and Concepts

Electricity consumption accounts for over 90% of greenhouse gas emissions of NTT Group's business activities--the Group consumes the equivalent of 1% of the power generation throughout all of Japan.

To combat this, the NTT Group has been working on Group-wide energy conservation activities dubbed the "TPR (Total Power Revolution) Campaign." By promoting efficient energy management at buildings owned by NTT and installing energy-efficient electrical power units, air conditioning systems and telecommunications equipment, we managed to continue to reduce electricity usage across the NTT Group by approximately 300 million kWh from projected levels in fiscal 2022.

Furthermore, the NTT Group is pushing for greater electricity usage efficiency with the aim of reducing the risk of business disruptions and helping to mitigate climate change. The fiscal 2025 target for power efficiency per data transmission in our telecommunications business, including data centers, has been set to double (EP100) that of fiscal 2017, and for fiscal 2030 the target has been set to ten times (environmental target 2030) that of fiscal 2013. In fiscal 2022 we achieved 8.0x of the former and 2.2x of the latter, reaching the 2x energy efficiency target three years earlier than planned. This is the first such achievement by a Japanese company that is a member of the international EP100 initiative.

The volume of Internet traffic in Japan has been growing rapidly, especially since 2020, due to the increase in work-from-home and remote meetings to prevent the spread of COVID-19. At the NTT Group we are continuing to enhance our telecommunications and network facilities to keep pace with advances in telecommunications technology and increases in traffic volume.

While this is accompanied by an associated increase in the energy usage of NTT Group, in the above mentioned energy-saving activities for the TPR Campaign we are working to save as much energy as possible and curb the increase in power consumption through annual target setting, performance management, formulation of measures, and implementation management.
We have continually made improvements in energy efficiency each year through these activities.

Energy-Saving Data Centers

NTT Communications offers data centers with a PUE*2 of less than 1.2, and NTT COMWARE offers data centers with a PUE of less than 1.1, which are at the top worldwide for energy efficiency. We are striving to enhance PUE for our other data centers as well, introducing five-star equipment with the highest level of energy efficiency in accordance with the NTT Group Energy Efficiency Guidelines. NTT FACILITIES has been developing technology for reducing the electricity consumption of data centers by incorporating higher efficiency technology for electrical power units and air conditioning systems as well as central air conditioning control systems.

Pursuing Initiatives across the Industry for Energy-Efficient ICT Devices

NTT is a member of the Telecommunications Carrier Association (TCA) and in that capacity, participates in the ICT Ecology Guideline Council*3, an organization that seeks to enhance the energy efficiency of telecommunications- related products. The council formulates guidelines on the criteria for evaluating the energy efficiency of telecommunications devices, and NTT has contributed to the technical aspect of this effort. The NTT Group's Energy Efficiency Guidelines are based on the guidelines created by this council. In August 2010, eight NTT Group companies*4 acquired the Eco ICT Logo on submitting self-evaluations of their CO2 emissions reduction efforts, including the establishment of Energy Efficiency Guidelines.

The Eco ICT Logo was created by the ICT Ecology Guideline Council to signify efforts by telecommunications service providers to reduce CO2 emissions. We will continue to drive the development and procurement of energy-efficient equipment, and work with the ICT Ecology Guideline Council to help bring both vendors and carriers together to promote the industry- wide procurement of energy-efficient equipment. We will ensure that vendors are consistently provided with requirements for NTT Group specification processes, and include energy efficiency information disclosure and our corporate stance on energy efficiency in our criteria for selecting vendors.

  1. *1 In October 2018, NTT was the first telecommunications carrier to become a member of the Climate Group's EP100 and EV100 initiatives. EV100 aims to achieve a 100% EV ratio for passenger vehicles by 2030.
  2. *2 Power Usage Effectiveness: PUE is calculated by dividing the total power consumption of a data center by the power consumption of the computing equipment it houses. It is a figure larger than 1, with higher efficiencies represented by values approaching 1.
  3. *3 ICT Ecology Guideline Council: An organization established jointly by the Telecommunications Carriers Association, Telecom Services Association, Japan Internet Providers Association, Communications and Information Network Association of Japan and ASP-SaaS-IoT Cloud Consortium to drive industry-wide efforts to address the issue of global warming.

    ICT Ecology Guideline Council (Japanese only)

  4. *4 The eight NTT Group companies are NTT, NTT East, NTT West, NTT Communications, NTT DOCOMO, NTT DATA, NTT FACILITIES, and NTT COMWARE.

Business Activity

Reducing power consumption throughout the network

NTT DOCOMO is developing technology that lowers power consumption of communication networks and is rolling out equipment that reduces power consumption. It is achieving this with efforts like developing more advanced sleep functions for base stations and installing air-conditioning control systems equipped with self-learning functions and actively rolling out 5G power-saving devices. Additional approaches include consolidating base station equipment and using power supplied directly from high-voltage direct current equipment with lower transmission losses.


Introduction of Internal Carbon Pricing System

To achieve carbon neutrality, a resolution was passed at the Executive Committee meeting in May 2022 to gradually implement an "Internal Carbon Pricing System" within Group companies. This system encourages reducing our impact on the environment by virtually converting CO₂ emissions into costs, and is used for decision making on procurement and other matters.


Contributing to reduced greenhouse gas emissions from society

At the NTT Group, we have set a target for fiscal 2030 which states that the amount of greenhouse gas emissions from society that can be reduced through the provision of our services and technology should be at least 10 times greater than the NTT Group's own emissions.

The aim of this target is to curb greenhouse gas emissions generated through our business and to contribute to the reduction of emissions from society as a whole by providing services and technologies.

The utilization of telecommunications, which is expanding every year with the spread of high-speed, high-capacity networks via smartphones and Hikari Collaboration, requires energy. However, on the other hand, the utilization of telecommunications contributes to the reduction of greenhouse gas emissions from society as a whole by reducing the environmental burden even more than the energy consumption required for the telecommunications, in the form of increased efficiency in society and reduction of physical items through digitalization.

*The volume of contribution to the reduction of greenhouse gas emissions from society is quantified in terms of the amount of greenhouse gas emissions from energy savings achieved through ICT services and other means. To quantify the energy-saving effect, we refer to the calculation methods of the Telecommunication Technology Committee (TTC) standard "Environmental Impact Assessment Methodology for ICT Products, Networks, and Services (JT-L1410)" and the Life Cycle Assessment Society of Japan's "LCA for Organizations of Information and Communication Technology (ICT) Businesses" study group.
*Examples of energy-saving effects that can be attained through the introduction of ICT services include energy management to reduce energy consumption in homes, companies, factories, etc., avoiding traffic congestion by analyzing traffic jam and public transportation operation data, and reducing energy consumption by streamlining and optimizing transportation schedules.
*The NTT Group's own greenhouse gas emissions include emissions of facilities required for other telecommunications companies and data center operators to deploy services.


Power efficiency of telecommunications business

As a target for fiscal 2030, the NTT Group has set a goal of power efficiency per data transmission in our telecommunications business, including data centers, of at least 10x1 that of fiscal 2013 levels. Electricity is essential for the continuation of telecommunications business and also accounts for more than 90% of our Group's greenhouse gas emissions. We have set increasing the efficiency of electricity usage as a target, based on the two perspectives of mitigating business continuity risk and alleviating climate change. Based on green procurement standards, we are introducing equipment with high energy-saving performance and improving the efficiency of network configurations.

Furthermore, in October 2018, we became the first telecommunications carrier to join EP100, an international initiative on energy efficiency launched by The Climate Group. By participating in such an international initiative, we will announce NTT Group's environmental initiatives to the world and demonstrate our commitment to international environmental issues.

In addition, we have achieved the EP100 target in our fiscal 2022 performance (doubling energy productivity by fiscal 2025 compared to fiscal 2017)

*1. Power efficiency per data transmission in our telecommunications business covers our five domestic businesses: NTT East, NTT West, NTT Communications, NTT DOCOMO, and NTT Data.
*2. An international initiative whose member companies set their sights on improving the power efficiency of their businesses (e.g., a 50% improvement in energy savings).

improvement rate with FY2013 as benchmark

Business Activity 2
Reduction of power consumption by introducing IOWN technologies

What is IOWN concept

An abbreviation for the Innovative Optical and Wireless Network (IOWN), this concept is a step for achieving a Smart World through the fusion of photonics-electronics convergence technology and three core elements--an All-Photonics Network, Digital Twin Computing, and Cognitive Foundation.

What is the IOWN (Innovative Optical and Wireless Network) Concept?

IOWN is a framework involving devices, networksand information processing infrastructure built onoptical and other innovative technologies, to deliverhigh-speed and high-capacity communications, andvast computing resources. IOWN consists of threekey areas of technology: the All Photonics Network(APN), which applies optical technology; DigitalTwin Computing (DTC), which enables advanced,real-time interaction between objects and peoplein cyberspace; and the Cognitive Foundation (CF),which deploys various ICT resources efficiently,including the aforementioned.

All-photonics network(APN) for achievingthe IOWN concept

This is the core concept that delivers a stable, high-capacity commu-nications network with computing capacity that exceeds the perfor-mance of conventional computing technologies and networks, withlower power consumption and overcoming communication latencyissues.

Future use cases achieved with IOWN

Going forward, the goal is to implement use cases raised at the IOWN Global Forum by demonstrating conceptual use cases among a wide range of companies and organizations.

Launch of APN IOWN 1.0

In March 2023, NTT East and NTT West initiated thefirst commercial service under the IOWN framework. Thishigh-speed broadband access service, powered by IOWN,is called the All-Photonics Network (APN). APN providesan optical-wavelength-exclusive service across the entirecommunications network. By implementing OTU4*1, whichuses optical wavelengths exclusively in all sections of thecommunications network and enables multi-accommodationwithin the optical transmission network at the interface level,we have achieved a latency that is an astounding 1/200th ofconventional latency*2, as well as zero signal fluctuation*3.
 With conventional IP/Ethernet services, the way latency occurred was inconsistent, making it difficult to predict and thereby complicating intricate remote tasks. With APN, the absence of signal fluctuations and a consistent latency level have made it possible to predict delays, thereby enabling a wide range of applications. Furthermore, adjustments and visualization of latency make it possible to synchronize timing between remote locations.

※1A standardized optical transmission network protocol recognized by ITU-T.Provided as an interface for high-speed broadband access services

※2Latency within the same prefecture where no video compression is required

※3Suppression of latency and packet loss due to traffic conditions by adoptingtime-division multiplexing (sending signals at fixed times to distinguishinformation)

What is APN?

Current networks consume a significant amount of energyby repeatedly converting between optical and electricalsignals. Moreover, latency issues arise due to communicationtraffic management. APNs seek to overcome these limitationsby converting all signals into optical signals, thereby creatinga network with higher capacity, lower latency, and morereduced energy consumption than now.

APN IOWN 1.0 Applications

IOWN Performance Targets

In addition to photonics-electronics convergencedevices, we are considering improvements in wavelengthtechnology and optical fiber technology. Starting in fiscal2025 with IOWN 2.0, we expect a 13-fold improvementin power efficiency in the APN section and an 8-foldimprovement in the server section, with a more than 6-foldincrease in capacity.
 Moreover, in fiscal 2029 with IOWN 3.0, we aim forfurther performance improvements, reaching up to 125-fold in terms of capacity.
 The power efficiency depends on the deployment of thedevice, but its performance will exceed that of IOWN 2.0,and it is expected to improve performance about 20-foldin the server section compared to existing solutions.
 Furthermore, we aim to achieve a 100-fold improvementin overall power efficiency, 125-fold in capacity, and1/200th of the latency with IOWN 4.0 looking toward fiscal2030 and beyond.

Our commitment

The reduction in power consumption resulting from rolling out IOWN will help reduce greenhouse gas emissions throughout the NTT Group's its business activities and society as a whole

Our objective

Reduce power consumption with the introduction of IOWN, and reduce the NTT Group's greenhouse gas emissions *1 compared to outcome.

※1GHG Protocol: for Scope 1 and 2

Background and Concepts

There is urgent need to create a society that can cope with global environmental changes such as climate change, major disasters, and pandemics. Developing next-generation energy technologies and technologies to enable resilient environmental adaptation will reduce the burden placed on the global environment and thereby prevent environmental destruction, opening the door to a sustainable society in which humans can continue to live in harmony with the environment. The NTT Group is committed to initiatives that reduce power consumption emissions throughout its business activities and society as a whole, by rolling out IOWN technology and increasing development and use of renewable energy sources.

Initiatives for Realizing the IOWN Concept

The development of ICT has dramatically increased the volume of information being transmitted through networks. Up to now, energy has been saved by enhancing power efficiency through the introduction and renewal of highly energy-efficient telecommunications equipment. However, the performance and efficiency of integrated circuit technology which has grown in line with Moore's law, is thought to be approaching its limits in terms of speed and energy consumption due to the restrictions of nanoscale fabrication and integration density. NTT Laboratories is advancing research and development that incorporates optical technology into signal processing with the aim of using photonics to realize a base for a new kind of computing. This has resulted in the development of a modulator with the lowest ever reported energy consumption and an optical transistor which transfers a high-speed optical signal to another light with gain (announced in April 2019).

The NTT Group is advancing the development of photonic technology and we have established the IOWN (Innovative Optical & Wireless Network) concept as one of the pillars of an all-photonic network that incorporates photonic-based technology throughout entire networks, including terminals. The target of this all-photonic network will be to realize power efficiency that is 100 times greater in areas where photonics technology is applied, and we expect it will radically reduce energy consumption. We are collaborating with global partners and specialists in a wide range of research and technological fields with the aim of realizing the IOWN concept.

Higher efficiency and lower power consumption using light image

Promoting Energy Conservation with IOWN

Conservation of the global environment and development of a sustainable society is the management theme of countless companies. The use of the NTT Group's next-generation communication platform "IOWN" for various ICT services used at customer companies not only helps to support these initiatives, but using IOWN extensively throughout NTT Communications' data centers, networks, and other infrastructure will lead to energy sav-ings, paving the way to achieve carbon neutrality at data centers and networks by fiscal 2030.


Business Activity

Highlighting the reduction in power consumption and other benefits of IOWN to the government

The NTT Group highlighted to the Japanese government the benefits of using its IOWN advanced technology, as a cutting edge communications infrastructure with major future potential for developing businesses in a wide range of fields. Rolling out IOWN to reduce power consumption and help achieve carbon neutrality provides Japan with a significant opportunity to lead the world in this sector.


Looking to the Future: IOWN

NTT R&D is envisaging the arrival of new smart societies that are not yet possible with today's Internet, with features such as mobility as a service (MaaS) for extreme fail-safe systems and entertainment services offering deep immersion. To realize such smart societies, we will require innovation that cannot be achieved merely by extending the trajectory of current technologies; we will need to realize ultra-low power consumption, high-speed signal processing, and the fusion of virtual worlds that can equal or surpass reality with sophisticated prediction technologies. The NTT Group has proposed the Innovative Optical and Wireless Network (IOWN) concept to realize new smart societies, and we are committed to realizing this concept.

In January 2020, the IOWN Global Forum was established in the United States by industry leaders NTT, Intel Corporation, and Sony Corporation, all three of which have superior expertise in the technological areas that form the core of IOWN. Wide-ranging recruitment efforts began in March 2020, with many companies both in Japan and overseas signing up as members, and specific technological considerations commenced through the use of online video conferencing. Going forward, we will work with a variety of partners for the earliest possible implementation of the IOWN concept.

Three Technological Layers that Constitute IOWN

Cognitive Foundation®

The Cognitive Foundation is a mechanism that centralizes management, operation, deployment, setting, and interlinking of ICT resources in different layers such as edge computers, network services, and user equipment, all from the cloud.

Technology development roadmap for realizing the IOWN concept

NTT proposes the "Digital Twin Computing Initiative"

All-Photonics Network

Photonics technology is applied not only to networks but also to information processing to achieve large-capacity, ultra-low power consumption and ultra-highspeed data transmission that had been difficult in the past. We can provide multiple functions that serve as the backbones of social infrastructure without mutual interference by assigning a function to each wavelength on a single optical fiber.

Digital Twin Computing

We combine highly precise digital information reflecting real-world objects, such as things, people and societies, to achieve large-scale, high-accuracy predictions and simulations of the future, and enable extremely advanced, real-time interactions between things and people in cyberspace.

Cognitive Foundation


Research and Development to Support the IOWN Concept

By using light as a means for transmitting signals inside the processors that perform information processing and calculations inside a computer, we hope to create a hybrid opto-electrical processor that will solve problems that arise with electrical processing, such as power consumption and increase in heat emission, and realize ultra-low power consumption and high-performance information processing. We have realized ultra-compact photo-electric conversion elements such as an optical transistor that uses nano-photonics technology.

To conduct a comparative time experiment by connecting several optical lattice clocks that are more precise than atomic clocks, the current standard for measuring seconds, we used the optical fiber network of NTT East for an optical frequency transmission experiment with the University of Tokyo. As a result, the required frequency precision for the comparative experiment was achieved, representing a major step toward conducting the experiment.

Increasing the Capacity of Optical Fiber Communication Networks

Increasing the capacity of mission-critical optical fiber communication networks has become an economic necessity. We have developed new proprietary technology for digital signal processing and ultra-wide area optical devices, increasing the channel capacity per wavelength to the point that transmission speeds achieve a level more than 10 times that of current commercial systems, and achieving a global first of 1 Tbps of capacity in long-distance wavelength-division multiplexed transmission trials. Furthermore, we also succeeded in developing an ultra-high-speed compact optical front-end module with integrated compact, wide-band InP optical modulator.
As another accomplishment, we realized high capacity wireless transmissions at approximately 10 times the speed of LTE and Wi-Fi, and five times that of 5G, by using the following two technologies.

The first one enables wireless transmissions at rates of 100 Gbps by using a method devised by NTT combining a principle called "OAM multiplexing" with MIMO technology.
This generates multiple radio waves of different frequencies so that they can transmit simultaneously without interfering with the each other. The result is a dramatic increase in the volume of data that can be transmitted simultaneously, enabling large-capacity communications.

The second one, which was jointly developed with the National University Corporation Tokyo Institute of Technology, enables wireless transmissions of 100 Gbps in the 300 GHz band. It is easier to expand the transmission bandwidth or terahertz waves, including the 300 GHz band, although they require high-performance devices. We developed an ultra-high-speed integrated chip (IC) for wireless frontend devices, leading to the world's first 100 Gbps wireless transmission in the 300 GHz band.

Optical Transistor Capable of High-Speed Operation with Ultra-low Powteer Consumption

As Moore's law approaches its limit in electronic circuits, there are expectations for a new, high-speed, energy-saving computing platform that incorporates optical technology. Achieving this requires technologies that have hitherto been considered difficult to achieve with low energy consumption, such as opto- electronic signal conversion and high-speed signal processing in the optical area.

NTT has been developing a semiconductor nanostructure called photonic crystals with which to realize various tiny optical devices. In this work, we used our nanotechnology to realize a nano electro-optic modulator (E-O converter) and a nano photodetector (O-E converter) with extremely small capacitance and low energy consumption.Moreover, through their integration, we also realized an O-E-O conversion optical transistor. These nano-optical technologies have opened the way to realizing high-speed, low-energy integrated opto-electronic information processing.

Business Activity 3
Developing and expanding the use of renewable energy

Our commitment

Developing and promoting greater use of renewable energy

Our objective

Increase the use of renewable energy, and reduce the NTT Group's greenhouse gas emissions*1 compared to outcome*2.

  1. GHG Protocol: for Scope 1 and 2
  2. The introduction of effectively 100% renewable energy (including actual renewable energy through non-fossil fuel certificates) will have the optimal types of energy determined on the basis of each country's energy composition, etc. Approximately half of the domestic renewable energy usage is anticipated to be from energy sources owned by NTT (FY2030).

Background and Concepts

The NTT Group is increasing its use of renewable energy* 3 as part of efforts to achieve its Environment and Energy Vision. The NTT Group is pushing ahead with development of renewable energy sources with the aim of generating around half of its renewable energy target from its own facilities by fiscal 2030.

Use of Renewable Energy

During fiscal 2022, a total of 2.7 billion kWh of power consumed (or 33% of power consumption, around 150% year-on-year) throughout the entire NTT Group was switched over to renewable energy sources.
In 2020, the NTT Holdings head office and four facilities of NTT Laboratories made the switch to effectively 100% renewable energy*4. As of April 2022, 132 buildings of the NTT East Group including the Hatsudai Building, 325 buildings of the NTT West Group, and 325 buildings of the NTT DOCOMO Group were among those that have already switched to renewable energy.

  • image
  • image

Development of Renewable Energies

Renewable energy like solar power, wind power, geothermal, and biomass do not generate greenhouse gases when producing power, an advantage that makes developing and expanding the use of renewable energy an essential part of initiatives aimed at achieving a decarbonized society. The NTT Group established NTT Anode Energy in June 2019 with the aim of delivering smart energy solutions that leverage the technology, expertise, and resources of the NTT Group. Focused on achieving a decarbonized society and the promotion of local energy production for local consumption, NTT Anode Energy operates on three core approaches: (1) Providing customers with green energy solutions; (2) Promoting NTT's own decarbonization efforts; and (3) Utilizing battery farms to increase use of renewable energy.

NTT Anode Energy is working together with various partners to develop renewable energy power plants in order to meet the green energy requirements of NTT Group companies. With a primary focus on sustainability, the company advancing development that takes into consideration ecosystems and living environments.

Business Activity

Initiatives rolled out at company buildings

By utilizing an off-site corporate PPA*5 mechanism, power derived from renewable energy, procured from NTT Anode Energy's newly constructed solar power plant, is being supplied into the NTT DOCOMO Okayama Building, which houses network facilities.
Greenhouse gas emissions at the NTT DOCOMO Okayama Building, where the new system will be installed, are expected to be reduced by approximately 7,500 tons per year (including non-fossil fuel certificates).


※3Includes actual renewable energy through non-fossil fuel certificates.

※4Refers to power generated from actual renewable energy that includes specified renewable energy through non-fossil fuel certificates.

※5Japan's first off-site corporate PPA scheme, which involves business operators building renewable energy power plants in locations removed from users for use exclusively by specified consumers, such as companies or municipalities, and supplying these users with electricity via the power grid over the long term.

Expanding the Use of Renewable Energy

Together with the development of renewable energy sources, the NTT Group is also expanding its concept of local energy production for local consumption to stabilize the power grid, by charging and discharging its constructed battery farms.

There are some 7,300 NTT buildings located around Japan, housing around 4 million kWh of battery storage capacity that the NTT Group uses to maintain communications in the event of power outages. The group will develop battery farm operations around Japan by utilizing these battery farms to increase the use of renewable energy and help stabilize the power grid. With these businesses, NTT Anode Energy will partner with subsidiaries ENNET and NTT Smile Energy to help overcome various challenges on the way to developing a carbon-free environment for all of society. This is achieved through a corporate PPA (Power Purchase Agreement), where customers use the electrical power generated from renewable energy power plants constructed on their sites or in remote locations.

Leading companies focus on the "Additionality" concept, where companies are encouraged to make investments in renewable energy projects as their selected source of financing, as a way of displacing the use of fossil fuels. NTT Anode Energy projects comply with the "Additionality" framework, so customers are able to use power generated from renewable energy via a corporate PPA.

Business Activity 4
Providing new services that contribute to carbon neutrality

Our commitment

Promoting the provision of new services that contribute to carbon neutrality

Our objective

Provide new services designed with the environment in mind, such as the development of services that use renewable energy, and visualization of the reduction in greenhouse gas emissions.

Background and Concepts

In addition to the Green of ICT, which will curb the environmental impact of NTT Group by introducing IOWN technologies and increasing the use of renewable energy, we will also work on Green by ICT, which will contribute to reducing the environmental impact of society as a whole.


In September 2021, NTT DOCOMO announced "2030 Carbon Neutral Declaration," committing to the reduction of the greenhouse gas emissions arising from its business activities effectively to zero by 2030.

In addition to its own business activities, DOCOMO has devised the slogan "Saving Our Planet With You" to help achieve carbon neutrality throughout the whole of society, together with its customers and partner companies. DOCOMO provides Green 5G as part of its service aimed at achieving carbon neutrality.

While the power used to recharge smartphones and other mobile devices may be the first thing one thinks of when it comes to the power that these devices use, a significant amount of power is actually consumed by mobile network communications that operate base stations and exchanges.

The majority of electricity in Japan still uses fossil fuels for power generation, thus resulting in greenhouse gas emissions like CO2 that is one of the causes of global warming. DOCOMO is making the switch to power sources free of greenhouse gas emissions, by using solar-powered green base stations and renewable energy (corporate PPA*1) generated by solar panels installed specifically for DOCOMO.The ratio of actual renewable energy*2 out of DOCOMO's total power consumption is higher than the ratio of 5G subscribers out of the total number of subscribers, which means the Green 5G service is provided effectively free of greenhouse gas emissions.

  1. PPA, an abbreviation of Power Purchase Agreement, is a scheme in which electricity users (DOCOMO) conclude contracts with power generation business operators to procure renewable energy over the long term.
  2. Achieves effectively 100% renewable energy, including non-fossil fuel certificates for specified renewable energy.


Greenhouse Gas Emissions Visualization Platform

To achieve carbon neutrality throughout society as a whole, the NTT Group has been providing a greenhouse gas emissions visualization platform.

In recent years, visualization of greenhouse gas emissions has been a prerequisite for companies' efforts in this area, but with so many different calculation methods available, choosing the best method has proven to be a difficult task. The most common method that companies use to calculate their emissions uses the formula "Amount of activity (quantity and value of raw materials and products)" x "Emissions intensity (fixed emissions set for that product (industry average))." The problem with this method is that the calculation results do not show any effects of reduction even when switching from older products to green products or services in order to reduce the amount of emissions.

The platform NTT provides utilizes primary data on the emissions of supplier companies and products to offer a calculation method that incorporates the results of emissions reduction efforts into the same reductions of procuring companies. This allows for efficient and effective visualization of emissions according to the company's efforts.

C-Turtle®, which is provided by NTT Data, a company implementing reduction support in addition to visualization, calculates emissions intensity by company based on the global company emissions and sales data provided by CDP, an international NGO. This is an effective way to collect and reflect data from suppliers who are already disclosing their own emissions appropriately.

NTT DATA is the only company in Japan licensed to use CDP's corporate emissions data.


On the other hand, CO2MOS, which is provided by NTT COM, is characterized by its ability to collect data directly from business partners through supplier engagement, and its ability to calculate product carbon footprints, which is in high demand especially in the manufacturing industry. We are promoting partnerships with companies in various industries for the purpose of business-to-business collaboration.
(Example: Marubeni-Itochu Steel)

Business Activity 5
Creation of innovative environment and energy technologies

Our commitment

Creation of innovative environmental energy technology for reducing global environmental impact

Our objective

Promoting the creation of innovation with next-generation energy technologies.

Background and Concepts

The NTT Group is creating innovative technologies aimed at addressing a range of issues related to the environment and energy such as climate change. In July 2020, we established the NTT Space Environment and Energy Laboratories for regenerating the global environment and achieving a sustainable and inclusive society. We will create technologies that will drive innovation in the field of smart energy, including next-generation energy, and for the future of the global environment.

Energy network technologies

Indoor direct-current power supply technology--a field that the NTT Group excels at--is being developed for outdoor use with the aim of achieving a high-resilience, autonomous, decentralized, and coordinated energy network to link NTT buildings and consumers in the surrounding area with direct current supply, for a flexible and efficient power supply system that is also reliable when disasters strike. Research is being conducted into technology that simulates information on energy demand, generation and storage capacities in cyberspace in an integrated manner, and applies the optimal figures to control the actual grid and achieve an ideal balance between supply and demand.

Another field of study is focusing on technology for the spatial and temporal reallocation of communications traffic between multiple regions or calculations and other information processing capabilities for more efficient use of renewable energy, which is prone to fluctuations due to weather conditions.

Sustainable systems technologies

Practical applications of technology that reduces CO2 in the atmosphere or water are being developed, covering artificial photosynthesis (based on an electrochemical approach) achieved with semiconductor technology and catalyst technology, as well as technology that maximizes the capabilities of plants and algae (based on a biological approach).

The electrochemical approach utilizes materials informatics to test combinations of materials that would not have been possible to discover using traditional experimental techniques or existing concepts. The biological approach involves research using digital twins, where various cultivation environments are recreated in cyberspace to test the effects of genome editing or climate control, before applying them to the real world for additional testing.

Proactive environmental adaptation technologies

We are focusing our efforts on research topics enabling society to take a proactive stance and adapt physically to extreme weather or environmental conditions. Lighting is an example of research being conducted on weather control.

We have developed advanced technologies as a means of protecting communications facilities from lightning strikes, and we are now expanding our research in this field to develop lightning control and lightning charging technologies.

More specifically, this research involves high-precision forecasting of areas prone to lightning strikes, employing lightning control technology so that drones trigger lightning strikes, and then lightning charging technology to store the energy from that lightning. The future goal is to develop floating lightning energy absorption systems that operate autonomously using natural energy including that from lightning strikes to absorb energy before the lightning strikes the ground.

Business Activity

NTT has teamed up with Euglena Co., Ltd. to begin a proof-of-concept for seaweed growth technology aimed at resolving climate change-related challenges by using neutron beams*1 to reduce greenhouse gases or create energy resources. The technology showcased with this proof-of-concept uses neutron beam irradiation to trigger genetic mutation*3 for increasing the useful characteristics*2 of algae, such as its CO2 (carbon dioxide) absorption and fixation potential and ability to produce oils that form the raw material of biofuels. Neutron beams have a much higher level of permeability than other types of radiation, and can provide an effective and irregular form of energy required for living organisms growing in liquids, like algae. Selecting and irradiating with suitable thermal neutrons or high-energy neutrons enable various forms of genetic mutation to occur, which will make it possible to grow and produce algae that is more usable, and more suited to particular applications. And in addition to reducing greenhouse gases or producing energy resources, the technology is hoped to play a role addressing various other climate change-related issues, with solutions involving the creation of food sources or agricultural, forestry and fisheries-derived feed.


  1. Neutron beam: A neutron is a particle that makes up an atomic nucleus. When a nucleus undergoes nuclear fission, neutrons are released from the nucleus along with kinetic energy. The unidirectional movement of this energy is called a neutron beam.
  2. Morphological characteristics: Refers to the properties or characteristics of living organisms.
  3. Genetic mutation: Refers to when the base sequence of DNA that makes up genes mutate from the original sequence. Genetic mutation modifies the functions of proteins that are made by genes.

Business Activity

<Green Software Development and Operation Technology Initiatives>

At NTT, by working to visualize CO2 emissions stemming from software we aim to reduce the emissions of the global supply chain as a whole.

Thus far, decarbonization has mainly been promoted in the hardware sector, but with the new aim of encouraging decarbonization efforts in the software field as well, we are working to formulate Japan's first carbon footprint calculation rules for software (we are currently participating in a calculation rule formulation support project run by the Ministry of Economy, Trade and Industry in cooperation with nine companies including companies inside the NTT Group).


Business Activity

In order to resolve the food and environmental concerns and social issues in Japan and around the world, NTT has partnered with Regional Fish to establish a joint venture company, NTT Green & Food, Inc., which began operations on July 1, 2023.

This joint venture company will first focus on producing and selling fish and shellfish by combining the technologies and knowledge of both sides. This includes the NTT Group's telecommunications technology spanning IoT and AI, and its production technology for algae that absorbs more CO2 and can be used as fish feed, and Regional Fish's advanced selective breeding and aquaculture technologies.