DOCOMO Conducts Green Base Station Demonstration With PLDT In The Philippines To Advance Decarbonization Technologies

Weather-Forecast-Linked Lithium-Ion Battery Control Technology of DOCOMO Deployed Overseas for the First Time

NTT DOCOMO, INC., together with the Philippine telecommunications operator PLDT Inc. and its mobile subsidiary Smart Communications, Inc., has successfully conducted a demonstration in the Philippines using renewable energy such as solar power^*1 and DOCOMO's weather-forecast-linked lithium-ion battery control technology.^*2 The technology automatically optimizes, based on the weather forecasts, the charging and discharging of batteries used at green base stations. The demonstration results showed that solar power utilization efficiency improved by 23 percentage points, from 38% before the demonstration to 61%. DOCOMO independently developed the technology for green base stations in Japan, and this demonstration marks the first deployment of this technology outside Japan.

For the demonstration, two green base stations were built—one near Metro Manila and one at a site in Cebu with different operating and power-supply conditions. In addition to solar power equipment and battery storage systems, the stations use DOCOMO's Energy Management System (EMS) platform,^*3 an energy management system incorporating weather-forecast-linked lithium-ion battery control technology. According to PLDT, this is the first initiative in the Philippines to optimize power generation, storage and supply at telecommunications base stations in advance based on weather and electricity demand forecasts.^*4

Conventional solar-only base stations rely on grid power at night and during bad weather and risk of service interruptions during power outages. The demonstration incorporates high-capacity batteries and a locally redesigned version of weather-forecast-linked lithium-ion battery control algorithm developed by DOCOMO.^*5 The system optimizes power generation, storage and supply around the clock, maintaining stable service at night and during outages while improving renewable-energy use, reducing grid-power consumption and CO_₂ emissions, and decarbonizing base stations.

As a shareholder of PLDT, DOCOMO has built a strong, long-standing relationship with the company through capital ties and technical cooperation. This demonstration is part of that collaboration and addresses the shared management priority of decarbonizing communications infrastructure through a long-term, stable partnership. DOCOMO will continue working with PLDT to build sustainable communications infrastructure in the Philippines and surrounding regions while promoting sustainable growth and creating new value.

DOCOMO's EMS platform used in this demonstration will be exhibited at Smart Energy Week, which opens at Makuhari Messe on Wednesday, September 9, 2026.

^*1 Repeatedly available energy sources such as sunlight and wind that do not emit greenhouse gases when generating power.

^*2 DOCOMO developed its weather-forecast-linked lithium-ion battery control technology in 2016. Based on weather forecasts, it automatically and flexibly adjusts the share of lithium-ion battery capacity reserved for communications backup during outages and the share used for routine solar charging and discharging, minimizing charge-discharge losses.

^*3 An energy management system that monitors electricity use and optimally controls power generation, storage and supply.

^*4 Source: PLDT, as of August 2026.

^*5 A paper on the control algorithm adapted to local climate and power conditions received the Second Best Paper Award at icSmartGrid2026, an IEEE-co-sponsored international conference held in Romania in July 2026.