What Are the Innovative Technologies for Overall System Energy Reduction?

5G networks are currently reaching a nationwide scale in many developed markets, offering an enhanced user experience and higher data rates to consumers and enterprise users. The foundational technology for most of these 5G networks is massive Multiple Input, Multiple Output (MIMO) where Active Antenna Units (AAUs) are implementing beamforming to increase cell and system capacity by an order of magnitude as compared with non-massive MIMO systems. However, this comes at a cost in terms of both capital expenditure and energy.

To meet these high data requirements for 5G, networks will need more infrastructure, leading to an overall increase in network energy consumption. A typical 5G base station uses three times more energy than a 4G base station, partly because AAU represents a significant operational cost for operators. According to Huawei, a 64T64R active antenna unit could consume up to 2 kilowatts (kW) compared with an LTE radio unit that typically consumes approximately 800 watts. Infrastructure vendors are investing heavily in research and development for innovative software and hardware to help operators achieve a lower level of energy consumption.

The 5G new-radio standard has been developed based on the knowledge of network traffic activity and the need to support sleep modes within radio-network equipment. Therefore, the standard offers better support to implement energy-saving features, and many vendors are already offering Artificial Intelligence– (AI-) driven energy-saving software to reduce energy consumption.

Aside from energy-saving software, vendors are also adopting innovative hardware technologies to target energy saving within the overall system. Some of the innovative technologies include:

• Gallium Nitride (GaN): High-output power and energy consumption requirements are pushing vendors to switch from laterally diffused metal-oxide semiconductors to GaN for Power Amplifier (PA). GaN enhances energy efficiency with properties such as high current density, high transition frequency, high breakdown voltage, low on-state resistance, and low parasitic capacitance. These properties translate into high output power, high efficiency, and wide bandwidth. GaN in a Doherty PA configuration can enhance efficiency by more than 50%, significantly reducing transmitting power consumption.
• High-performing chipsets: The new generation of chipsets is very energy efficient. Nokia’s ReefShark can cut energy usage by up to 64%; Ericsson Silicon can reduce energy usage by 30% to 60%; and Samsung’s new system-on-chip can enable energy savings up to 70%.
• Liquid cooling: According to Nokia, 90% of the electricity consumed by base stations is converted into waste heat; every kilowatt hour (kWh) of heat requires one kWh of cooling. Compared with traditional air-cooling systems, liquid cooling could reduce energy consumption of a typical base station by up to 60%. Moreover, operators have the opportunity to sell the heat as usable energy.
• New architecture/design: Huawei recently released its latest AAU. MetaAAU incorporates ultra-large antenna technology that supports 384 antenna elements, doubling the number of a traditional AAU. It has been tested in the 5G Capital Project, a joint innovation project by Huawei and China Unicom with a theme of “Smarter, Together,” and has proved to be an effective energy-saving tool. It enables the base station to achieve the same coverage at a lower transmit power level, reducing power consumption by 30% over conventional AAUs. ZTE’s V-tooth heat dissipation design has been applied to 5G base stations. When integrated with new phase change inhibition material, it improves the heat dissipation efficiency by 20% and reduces the temperature of the system and core components, contributing to significant energy savings.

Vendors play a key role in lowering the carbon footprints of a network, and they should continue to focus on energy efficiency and energy reduction when producing their products. Vendors should also accelerate AI integration within energy management solutions to manage all elements affecting energy consumption. According to Ericsson, intelligent site control solutions can help reduce site energy consumption by up to 15%.

Operators should deploy more energy-efficient equipment along with any software that helps to bring down power usage. In this way, they can choose to switch off some of the components in the radio access network that are not required during low traffic, contributing to significant energy savings. Since renewable energy and energy storage devices are becoming more affordable, operators should use them where possible. Moreover, operators should deploy and support any real-time monitoring tools based on AI as it reduces the number of site visits and offers a better network performance overview, improving the overall efficiency.