The global information and communications technology (ICT) sector’s life cycle carbon footprint was around 760 million tonnes of carbon dioxide equivalent (Mt CO2e) in 2020, equivalent to 1.4% of global greenhouse gas (GHG) emissions.
The sector used around 920 terawatt-hours (TWh) of electricity in 2020, or around 4% of global electricity use. Despite huge increases in demand for digital services, electricity use has increased by only 15% since 2010, while carbon emissions rose by 6%. Over the same period, global electricity use across all sectors rose by 28% while total GHG emissions rose by 5%.
The carbon emissions of the ICT sector include the following:
User devices primarily intended for entertainment and media such as televisions and gaming consoles are counted separately from the ICT sector, following ITU-T Recommendation L.1450. The entertainment and media sector, which includes TVs, TV peripherals, and gaming devices, accounted for an estimated further 1% of global GHG emissions. These figures also exclude cryptocurrencies, such as Bitcoin mining, which accounted for around 0.1% of emissions.
These estimates are taken from a 2023 study by Malmodin et al. The study combines extensive sales data on devices and equipment with reported energy use and emissions data from companies in the sector. It builds on previous studies, including Malmodin & Lundén (2018) and Malmodin et al. (2010).
An older but frequently cited study by Andrae & Edler (2015) presents three different scenarios for how the energy use and carbon emissions of the ICT sector could evolve to 2030. Media articles have frequently cited the ‘worst case’ scenario in this study, which projects that the ICT sector could use half of the world’s electricity by 2030 and emit one-quarter of the world’s carbon emissions. The authors have published an updated 2020 study, reducing their estimates on energy use by 31% in 2020 and 61% in 2030.
The ITU L.1470 standard, GHG emissions trajectories for the ICT sector compatible with the UNFCCC Paris Agreement, was published in 2020, outlining the pathway needed to meet the global climate goals of the Paris Agreement. These guidelines are the first targets specific to the ICT sector that have been approved by the Science-Based Targets Initiative. It requires cuts of 45 per cent by 2030 and sets out a roadmap for meeting net zero carbon emissions by 2050.
The majority of mobile operators are now disclosing their climate impacts, energy and GHG emissions via the internationally recognised CDP global disclosure system. The GSMA, the mobile industry association, is working with operators to help them commit to targets aligned to the new net zero pathway for the sector. Many of these operators have also committed to or have set near-term Science-Based Targets.
Energy efficiency and renewable energy are expected to account for most of the sector’s operational emissions reductions over the next decade, along with collaboration with suppliers to drive reductions through the supply chain. The latter is vital, as supply chain emissions can represent over two-thirds of the industry’s carbon footprint.
The energy efficiency of data networks has improved rapidly over the past decade. A 2018 study found that the energy intensity of fixed networks had halved every two years since 2000. Another study estimated that the energy needed to transmit one gigabyte of data over mobile networks had decreased by over 95% between 2010 and 2017. ICT companies are also investing into R&D programmes to ensure that next-generation equipment can be even more efficient to keep pace with growing demand for digital services.
ICT companies are already leading buyers of renewable energy, accounting for about half of all corporate renewable energy purchases in recent years. Several data centre operators and network operators have purchased enough renewable energy to match 100% of their annual consumption. These companies are also playing an important role in demonstrating and investing in early-stage clean energy technologies such as green hydrogen, advanced nuclear, and direct air capture.
Yes, the sector is seeking to offset its impact: and it is a trend that has positive system-wide benefits.
ICT companies are major buyers of renewable energy, accounting for about half of corporate renewable purchases in recent years. In a study of global telecom operator energy and carbon footprint performance for the period of 2010 – 2015, the share of renewable electricity was around 46%. A more recent study of European operators estimated that the share of consumed renewable electricity was around 55%.
Purchases and commitments by ICT companies have helped to scale renewable energy, helping to drive down costs while expanding renewable energy access into new markets. Several data centre and network operators have reached 100% renewables in recent years, purchasing enough renewable energy to offset their energy use for a given year.
However, in any particular hour, the data centre or network operator might be drawing more or less power than the wind or solar facility is generating that hour, and accounting for that real-time variation is the next step for renewable electricity use by data centres.
As energy storage becomes more common and renewable electricity generation becomes more widespread, this challenge will get easier. It may also unlock a role for data centres in demand side energy management. ICT companies are well equipped to participate in this newly emerging market because they are already familiar with combining digitalisation, back-up power and uninterrupted power supply. Data centres can play an important role in dynamic power systems that balance supplies of electricity from generators with demand from users.
The average lifespan of mobile phones today is around three years, far short of its technical lifespan of around eight years. After upgrading, some handsets enter a vibrant second-hand market or are given to friends or family, but a large share are hoarded at home. The GSMA estimates that there are over five billion dormant phones in the world today, containing over 50,000 tonnes of copper, 100 tonnes of gold, and enough cobalt to make 10 million electric car batteries.
Some manufacturers have begun to focus on increasing, retaining or recovering a product’s value, either by extending longevity and/or facilitating take back, repair, refurbishment, and resale. This, in turn, is leading to partnerships across the value chain or establishing their own in-house repair and refurbishment services.
In 2023, leading operators around the world signed up to a new set of pace-setting targets developed with the GSMA, commiting to increase take-back of mobile phones and ensuring that all recovered phones are repaired, reused, or responsibly recycled.
Governments can also play an important role in increasing the circularity of mobile phones. For example, the European Commission has proposed new rules to make devices more energy efficient, durable, and easier to repair.
Digital technologies and services, including emerging technologies such as 5G, IoT, and AI, hold great potential to reduce carbon emissions globally, across numerous sectors and industries.
Recent reports from the GSMA showed that the ICT sector is already making a significant contribution to combating climate change by reducing the emissions of other industries through smart connected technologies and behaviour change. The GSMA estimates that emissions savings enabled by mobile technologies could be ten times larger than the global carbon footprint of the mobile industry itself.
Reports from other organisations such as the World Economic Forum and the Exponential Roadmap Initiative have also shown how digital technologies and services are a key lever to achieving net zero.
Digital technologies can also enhance climate resilience. For example, social media can help crowdsource data on vulnerable areas, IoT sensors can help monitor soil quality in agriculture, and virtual and mixed reality can help visualise climate impacts and promote adaptation strategies.
Digital technologies can have both positive and negative effects on climate action. Policies and technology choices can help guide its use to maximise the benefits while minimising the risks.
Although 5G networks allow for much higher data traffic, they are also designed to be more energy efficient than their predecessors. For example, advanced sleep modes and the use of AI can help to reduce energy consumption. With the deployment of 5G, operators have also taken the opportunity to rethink how to build, operate and manage networks in a smarter and more strategic way.
Mobile operators will increasingly be able to use network function virtualisation, software-defined networks and network slicing to tailor the connectivity to the needs of the application. That will mean less energy is wasted. Although 5G is likely to drive a massive expansion in the number of ‘things’ connected, many of these connections will consume very little energy. For example, some narrow-band Internet of Things (NB-IoT) connected devices will be able to function for a decade using a single battery.
The overall energy and emission impacts of 5G are still uncertain. 5G networks will be denser than their predecessors, employing more base stations and other infrastructure. Moreover, many mobile operators will run 2G, 3G, 4G and 5G networks in tandem for much of the next decade, placing upward pressure on their energy usage. However, carefully managed decommissioning of legacy 2G and 3G networks are a key opportunity to reduce mobile network energy use over the next several years.
The Internet of Things (IoT) is a network of physical devices, including things such as personal health monitors, smart appliances, and autonomous transportation systems, which are embedded with digital technologies that enable the devices to interact with each other by collecting and communicating data. IoT is already in widespread use today, for example, in smart factories to improve the efficiency and maintenance of equipment.
Generally, the direct impact of IoT on energy consumption is negligible, since the added consumption from the IoT sensor or device is relatively small. However, the smart functionality that is enabled by IoT could save much greater amounts of energy, such as turning off air conditioning when occupants leave the home or adjusting temperature controls automatically. Reducing standby energy use is critical to ensure that overall energy use of IoT-enabled devices does not result in a net increase in energy use and emissions.
The main energy and climate impacts will come from the application of IoT, including in smart electricity grids, smart homes, smart cities, health monitoring, transportation system control, and environmental management. Current deployments of IoT suggest that it is generally used to improve operational efficiency, which usually means a reduction in energy used and therefore carbon emissions.
Ultimately it is hard to predict the long-term effects of the IoT. Research into its broader effect on energy use faces four uncertainties: What IoT applications will be broadly adopted, how much will they communicate, how will human behaviours change in response, and how will sensors be powered?
Digitalisation across all sectors offer significant opportunities to support the system changes needed to transition to net zero economies – from more accurate climate modelling and energy services to supporting smarter cities and home working.
However, the rapid growth in demand for digital services raises questions about how the carbon footprint of ICT could change in the future. The best starting point for understanding the future is to analyse historical developments, evaluating real-world measurements of electricity consumption and data traffic in light of expected future developments.
Looking at data from recent years, the electricity consumption and carbon footprint of the ICT sector does not follow the same trends as data traffic. Between 2015 and 2022, internet traffic increased by 600% and data centre demand more than quadrupled, while energy use of data networks and data centres increased by just 5% per year.
In addition, energy efficiency improvements across the sector, the transition to renewable energy, together with replacing larger devices with smartphones, continues to limit ICT’s footprint, despite the ongoing build-out of networks and rising subscriber numbers.
Looking ahead, it is likely that data traffic will continue to rise exponentially, but that ICT’s carbon footprint and electricity consumption will not follow, due to continued developments in efficiency and the phasing out of older networks and access technologies paired with increased usage of renewables.
Claims that digital technologies will consume a significant share of global electricity over the next decade are therefore, unreasonable (as well as far too expensive to support).