The operator is testing a hybrid-powered base station in Japan that offers a look at how operators can check carbon footprint without sacrificing service continuity
Hybrid-powered base station: SoftBank is experimenting with a hybrid-powered base station that can significantly reduce base station emissions.
Designed for disaster: The operator plans to use it during power outages to ensure service continuity, but will consider it for other use cases as well.
Decarbonization with AI: Beyond the renewable power trial, the company has also developed an AI-driven sleep control system for base stations that can curb energy use during low-traffic hours.
Softbank has ambitious net-zero targets, and it’s going the hybrid route to get there. The Japanese operator has recently started testing an environment-friendly base station in Ichihara City, Japan that runs partly on renewable energy.
One-third of the base station’s power draw comes from solar and wind energy. According to the company, the base station demonstrates reduced carbon footprint through self-generation of this power, a feature that allows it to run independently through power outages and ensure connectivity through disruptions.
SoftBank said at this time, it plans to use the base station for only times of disaster when non-renewable-powered base stations cannot function, while indicating that it might broaden the scope of the test later this year to include other areas.
The hyrbid power architecture has certain advantages, key among of which are less susceptibility to weather patterns or time of the day, ability to automatically switch between renewable and non-renewable power sources when reserve is low, and continued operation through power outages.
One unique feature is a built-in diffuser which can collect and accelerate wind, generating power efficiently even in low wind speeds of 3 m/s. This makes it suitable for installation in remote sites where wind conditions are unstable.
“By utilizing this base station, we will increase the proportion of renewable energy used in the electricity used at the base station and build a new model for decarbonizing communications infrastructure,” SoftBank said.
Separately, the operator has developed an AI sleep control system to dynamically control the active and dormant states of base stations. The system allows operators to automatically put base stations in a low-power mode during periods of low traffic, helping cut back power consumption without disrupting service. SoftBank expects to see a reduction in power consumption of roughly 5 million kWh per year with it.
Carbon footprint of cellular base stations has become a growing concern as their numbers have surged worldwide with the emergence of 5G. Base stations require energy to operate which accounts for a majority of their lifecycle emissions. An IEEE study found that the energy consumption is so high that base stations in radio access network (RAN) make up half of mobile operators’ total energy expenditure. As hundreds of thousands of new sites are deployed every year to support 5G connectivity, the resulting energy consumption and carbon emissions at a national scale are becoming increasingly difficult to ignore.
Fortunately, operators are beginning to shift toward low-carbon energy sources which over time could reduce carbon footprint of base stations and check their environmental impact.
SoftBank began stepping up its sustability efforts in 2021 under the leadership of president and CEO, Junichi Miyakawa. The current trial is part of a broader push to achieve net-zero emissions across its entire supply chain by 2050. The operator has also set a target to switch to 100% renewable energy for business activities by 2030 — a milestone that will cut its reliance on commercial energy sources by half.
