NGMN Alliance digs down on energy savings for MNOs

The need to reduce energy usage is a pressing and ongoing concern for the mobile communications industry as companies seek to cut spiraling costs and meet net zero targets in the coming years. 

Indeed, the latest edition of the Ericsson Mobility Report said the ICT sector consumed about 4% of global electricity in the use stage, representing about 1.4% of global greenhouse gas (GHG) emissions in 2020. Up to 2030, it is forecast that electricity consumption will grow slightly, while carbon emissions will fall. The report said the sector’s use of electricity is the primary contributor to its GHG emissions.

Given the challenging environment, the Next Generation Mobile Networks (NGMN) Alliance has taken it upon itself to provide mobile network operators (MNOs) with further guidance on how they can mitigate high energy costs through their technical strategies. 

Arash Ashouriha, chairman of the NGMN Alliance Board and SVP group technology at Deutsche Telekom, observed, “For the last 18 months, high energy costs have put a renewed focus on technical strategies to reduce and better manage energy consumption as well as to ensure network resilience and stability.”

The 20-page report, titled "Effective Energy Saving Strategies and Best Practices for MNOs," is a follow-up to the NGMN’s network energy efficiency roadmap, "Green Future Networks: Network Energy Efficiency Phase 2," and aims to provide MNOs with best practice energy saving and energy management techniques.

MNO to-do list

The alliance said its latest report is the first to demonstrate a collective MNO response to the challenging energy landscape through reduction in energy consumption and efforts to safeguard energy stability without negatively impacting the network performance.

MNOs are of course already implementing a number of energy-saving measures, from shutting down legacy networks to installing more energy efficient RAN equipment. Indeed, the NGMN Alliance remarked that the RAN accounts for around three-quarters of all mobile network electricity consumption.

MNOs are also deploying monitoring systems to analyze and improve energy efficiency, implementing liquid cooling systems, and switching off capacity during off-peak periods. A further challenge is to ensure a resilient and affordable energy supply through methods such as the production of renewable energy and optimizing battery usage at RAN sites.

Given all this activity, certain best practices are emerging. For MNOs, the recommendations are: 

  • Accelerate the transition from legacy networks (such as 2G and 3G) to more energy efficient technologies (such as 4G and 5G) whenever possible.
  • Deploy additional 5G/4G spectrum refarmed from 3G to increase network data throughput and capacity, and to keep up with the high data growth experienced during the past years.
  • Leverage the capabilities of the latest RAN technologies to achieve higher energy efficiency.
  • Implement Intelligent RAN energy saving features to save more energy in both 4G and 5G layers.
  • Update RAN sites with state-of-the-art energy efficient RAN equipment and antennas, which facilitate all mobile generations, 2G to 5G.
  • Replace onsite air-conditioning units with energy efficient cooling.
  • Deploy renewable energy sources and battery storage units, which reduce the network dependency by electrical grids.
  • Use intelligent energy saving features together with battery storage equipment to further increase the network stability.

The NGMN Alliance also provides two cases where these practices have been implemented with measurable results. 

For example, it said deployment of some of these solutions has allowed Dutch telco KPN to keep energy consumption flat over the period from 2018 to 2022, while data traffic increased by 33% annually. 

“Similarly, in the past five years, in the Vodafone network, data traffic has increased over 600% yet the absolute energy consumption has not changed, representing a reduction of energy consumed per unit of data traffic of nearly 90%,” it added.

Laurent Leboucher, member of the NGMN Alliance Board and group CTO and SVP Orange Innovation Networks at Orange, also said a further publication on this topic is due in the first quarter of 2024, “which will provide longer term guidance including on how radio access network (RAN) sharing is a significant and cost-effective way of saving energy.”