Preventing Global Warming

DOCOMO has implemented various measures to reduce emissions of greenhouse gases. Communications facilities, however, continue to be expanded in order to provide new services and improve service quality, so greenhouse gas emissions tend to increase alongside increased power consumption. We estimated that CO₂ emissions in fiscal 2010 would amount to 1.37 million tons-CO₂ if we had simply continued existing measures against global warming. Therefore, in order to enhance efforts aimed at reducing environmental impact, we set a new goal of reducing CO₂ emissions in fiscal 2010 to less than 1.17 million tons-CO₂, 15% less than initial estimates. To achieve the target we installed power-saving equipment and extended the successes of the Tachikawa ICT Ecology Center to commercial facilities. As a result of these and other efforts, we met the target, with fiscal 2010 emissions coming in at 1.108 million tons-CO₂.
Going forward, we will implement further energy-saving measures and promote further reductions to greenhouse gas emissions.

Calculated with a conversion coefficient (0.378kg-CO₂/kWh).

In December 2010 DOCOMO began providing the XiTM ("crossy") service using LTE1, a new mobile phone communications protocol, and remote radio equipment (RRE) with reduced environmental impact was developed for optical feeder base stations2 used by the new service.
RRE use 26% less power than conventional equipment and are compact and lightweight, meaning environmental impact is also reduced during transport to base station sites. RRE can be used with base stations for the FOMA service as well, which is based on the existing W-CDMA communications protocol, so if RRE are installed when establishing new optical feeder base stations for the FOMA service, XiTM can be provided simply by adding base station equipment for that service, which makes it possible to efficiently expand the XiTM coverage area. RRE have been installed at approximately half of the base stations providing the XiTM service as of the service's launch. And, they were installed on all optical feeder stations for the FOMA service that were newly added in fiscal 2010.

• 1 An abbreviation of Long Term Evolution. A mobile communications protocol based on specifications drawn up by the 3rd Generation Partnership Project (3GPP), a standardization body. It materializes high-speed data transmission with a maximum down link speed of 100Mbps or more.
• 2 A secondary base station established apart from the primary base station and connected with optical fiber.

Power consumed by communications facilities accounts for a large portion of the CO₂ emitted in our business activities.
The Tachikawa ICT Ecology Center was established to test and verify the feasibility of the cutting-edge energy-saving technologies with the goal of reducing power consumption by communications facilities. The center began testing DC power supply systems, new air conditioning technology and an energy-saving server in fiscal 2009 and verified a reduction in CO₂ emissions of up to 66% compared to conventional systems and equipment.
In fiscal 2010, we achieved a reduction of 1,639 tons-CO₂ by implementing these measures at commercial facilities.
In fiscal 2011 and beyond, we plan to expand the introduction of proven, new technologies facilities developed by the center.

The eight companies of the NTT Group, including DOCOMO, formulated the NTT Group Energy Efficiency Guidelines in April 2010 and began implementing them in May 2010. The guidelines stipulate a basic approach to development and procurement of ICT equipment used by the NTT Group such as routers and servers.
Over 90% of the CO₂ emitted by the NTT Group comes from use of electric power by communications facilities and offices. Accordingly, in order to effectively reduce emissions, ICT equipment used by the Group must be developed and procured with an emphasis on energy efficiency performance in addition to function, performance and cost.
The guidelines use standard values for each type of equipment stipulated in the ICT Ecology Guidelines drawn up by the ICT Ecology Guideline Council, of which NTT is a member, as indicators for the energy efficiency performance of ICT equipment newly developed or procured by the NTT Group.

(Open this content in a new window)NTT Group Energy Efficiency Performance Guidelines

Company cars used by employees primarily for sales activities are being switched over to low-pollution vehicles3.
In fiscal 2010 we added 66 new low-pollution vehicles to the fleet. As a result, DOCOMO now has a total of 2,280 low-pollution vehicles (as of March 31, 2011), which account for 90.7% of the vehicles used by the company. We intend to continue adding even more of these vehicles going forward.

• 3 Low-pollution vehicles include electrics, hybrids, natural gas and LPG (liquefied petroleum gas) powered vehicles and locally specified low-emission gasoline vehicles (at least 25% lower emissions).

All offices occupied by Group companies work to reduce energy consumption, use of paper resources and regular waste based on an in-house set of guidelines, the NTT DOCOMO Group Office Eco Procedures. The guidelines call on employees to reduce paper use through double-sided printing and paper-free meetings, sort all waste into the appropriate categories, turn off unnecessary lights, and use energy-saving features on computers.

Our efforts to reduce greenhouse gas emissions include participating in "Cool Biz" and "Warm Biz" (dressing in seasonally appropriate clothing to reduce heating and cooling loads) as well as active implementation of energy-saving activities like turning lights off during breaks. We also participate in the CO₂ Reduction / Light Down Campaign4. In fiscal 2010, we turned out the lights on lighted facilities in 34 locations around the country, including wall-mounted logo signs, outdoor advertising and billboards, on June 20 and July 7 during the campaign period.

• 4 A campaign sponsored by the Ministry of the Environment that calls on companies to turn off lighted facilities in order to help prevent global warming.