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).
The total life cycle carbon footprint of the ICT sector is approximately 700 million tonnes carbon dioxide equivalent (Mt CO2e) per year. This is equivalent to 1.4 per cent of global carbon emissions and around 4 per cent global electricity use.
While total electricity consumption has increased by approximately 5 per cent since 2015, the carbon emissions of the sector have dropped from around 730 Mt CO2e due to higher levels of renewable electricity use both globally and from specific investments by ICT companies.
The carbon emissions of the ICT sector cover the following:
The entertainment and media sector is counted separately. This covers the use of TVs, games consoles, streaming of music and video, and printed media such as newspapers. This sector accounts for an estimated further 1.1 per cent of total CO2e and approximately 3 per cent of global electricity consumption.
These figures exclude cryptocurrencies, such a bitcoin mining, which is estimated at 0.2 per cent of global electricity use, and the use of surveillance cameras, which is approximately 0.15 per cent.
This data is taken from Jens Malmodin and Dag Lundén. 2018. The Energy and Carbon Footprint of the Global ICT and E&M Sectors 2010–2015 with more recent data included to update the figures. The results are derived from an extensive collection of actual sales, electricity usage and carbon emissions of the companies in the sector.
An older but frequently cited study presents three different scenarios for the expected consumption depending on the expected technology efficiency increase. The unrealistic ‘worst case’ scenario in this study (which suggests that the ICT sector could use as much as a fifth of overall electricity by 2030) in this study has been reported in media articles, despite the report authors highlighting more likely outcomes.
A new international standard for the ICT sector has recently been published that outlines the pathway needed to meet the commitments outlined in 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.
To date, more than 50 mobile operators, which together account for around two-thirds of mobile connections globally – 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.
Globally, 29 network operators representing more than 30 per cent of global mobile connections and 50 per cent of mobile industry revenues have committed to setting Science-Based Targets, along with 35 hardware manufacturers. To date, 28 techUK members have signed up.
A shift to renewable energy is expected to account for most of the sector’s reductions over the next decade. Companies will also achieve greater energy efficiency and deepen relationships with suppliers to drive reductions through the supply chain. The latter is vital, especially for short-lived user devices, as supply chain emissions can represent two-thirds of a companies’ full footprint.
If the ICT industry, ICT suppliers and end-users all switch to using renewable energy then the carbon footprint of the ICT sector would be cut by more than 80 per cent. The sector is already a significant buyer of renewables. ICT companies operating large data centres are leaders in corporate procurement of renewables, accounting for about half of global procurement of renewables in recent years (IEA) and driving renewable deployment across the world through Power Purchasing Agreements (PPAs). The top six off-takers of renewables in 2019 were all ICT companies, led by Google.
Other activities to decarbonise the sector include investing in energy efficient networks, virtualisation of networks, deploying energy conservation measures, utilising free cooling,
Significant investment and R&D programmes are also in place covering energy technologies, battery innovation, energy efficiency, network efficiency, eco-design of products, re-use of equipment, repairing and recycling, climate-tech (covering agriculture, supply chains, buildings, energy, industry and cities) and climate and environment data analytic tools and platforms.
ICT solutions, including IoT, machine learning and automation, have great potential to reduce carbon emissions globally, across numerous sectors and industries. Furthermore, advanced analytics and cloud computing are helping climate scientists better understand the challenges facing the planet.
A recent report by 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 study assessed the enablement impact of mobile communication technology on a global scale. The use of mobile technology powered a global reduction in greenhouse gas (GHG) emissions of around 2,135 million tonnes CO2e in 2018. The emissions savings were ten times greater than the global carbon footprint of the mobile industry itself.
Further deployment of existing technologies to address global warming could cut global carbon emissions by a further 15 per cent. In terms of global decarbonisation, this equals almost one‑third of the halving of emissions deemed crucial by 2030.
New technologies such as 5G, IoT and AI create emission reduction opportunities. Use cases for AI, for example, are emerging that indicate the technology can play a significant role in carbon mitigation and adaptation. A report by Microsoft and PwC estimated that AI could cut 2.4Gt CO2e in 2030, equivalent to the 2030 annual emissions of Australia, Canada and Japan combined. Initiatives such as Microsoft’s AI for Earth attempts to equip NGOs and policymakers with the data, software, and tech to begin to apply AI to conversation and environmental management.
There has been discussion of rebound effects where technology decreases carbon emissions from one activity but increases it in another. An example would be homeworking, where the emissions from commuting are avoided but energy usage increases at home. In this example, as in most sustainable digital solutions, the rebound effect is small and outweighed by other savings.
Across the economy, carbon emissions have dropped significantly as manufacturing has shut down, businesses are closed, and travel is reduced. At the same time, data traffic across ICT networks has shifted as a result of COVID-19 as more people work, live and socialise from home. This data shows that fixed networks (broadband and Wi-Fi) have recorded the largest increases, ranging from a 20 per cent to 100 per cent increase. Data traffic across mobile networks (3G and 4G) has shown a different pattern as fewer people are moving around. For these networks there has been a 10 per cent drop in urban areas and up to a 20 per cent increase in suburban and rural areas.
The biggest change has been in voice services. For example, voice-over Wi-Fi services have seen increases of 90 per cent for some US-based service providers, and 180 per cent in the Netherlands. In Europe, Spain, Germany and Switzerland have seen increases in mobile voice calls of up to 50 per cent in recent weeks.
In the UK BT has seen a 100 per cent increase in daytime traffic across its fixed broadband network. For mobile data, the traffic has fallen slightly since before the virus as more people connect to Wi-Fi. BT reported no noticeable increase in electricity use or carbon emissions.
In Spain, Telefónica has seen a 35 per cent data increase over its networks in Spain (26 per cent fixed network and 48 per cent mobile network) with no increase in electricity usage. There have also been increases in data traffic in the UK and Germany, but at a lower level, and without a significant increase in electricity usage.
The Nordics operator Telia, with operations in Sweden, Finland, Norway, Denmark, Estonia, Latvia and Lithuania reported an electricity consumption increase of less than 1 per cent across its mobile network, despite a 20 per cent mobile data increase, and electricity use was unchanged across at its fixed and core network operations.
Although 5G networks are likely to drive a dramatic increase in mobile traffic, they are also designed to be more energy efficient than their predecessors. Crucially, 5G and related technologies give mobile operators precise control over their networks’ performance and, by extension, energy consumption. Operators have taken the opportunity of 5G’s introduction 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 NB-IoT connected devices will be able to function for a decade using a single battery.
5G networks will be much 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 before they are able to realise savings by decommissioning legacy networks.
However, some operators have decided to decommission both 2G and 3G networks, not the least due to reuse of frequencies, and by that, a higher degree of energy efficiency will be achieved.
In addition, mobile broadband solutions such as Fixed Wireless Access (FWA) will replace older xDSL copper based broadband networks, especially in rural areas, delivering greater energy efficiency as well as future proof broadband access network with significantly lower environmental impact due to copper network maintenance.
Energy efficiency is important to the mobile subsector and ICT sector because electricity costs are a significant overhead, so network operators work closely with equipment manufacturers on energy efficiency. 5G and related technologies give mobile operators precise control over their networks’ performance and, by extension, energy consumption.
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 use today, for instance in electricity meters, to facilitate logistics and in traffic monitoring. So far, the impact on electricity consumption is negligible, since the actual consumption of the connected IoT devices is small. But the main impact will come in future as IoT has the potential to further transform human lives with applications including smart electricity grids, smart homes, smart cities, health monitoring, transportation system control, and environmental management. The IoT will also affect energy production and use, which will, in turn, affect the environmental impacts of the energy system.
IoT technologies can have complex effects on energy use. For example, adding smart functionality to an existing appliance, such as a thermostat, normally causes a small increase in energy used by the temperature control system because of the addition of new sensors, electronics, or displays. That smart functionality, however, may allow the appliance to operate in a way that saves much greater amounts of energy, such as turning off air conditioning when occupants leave the home or adjusting temperature controls automatically.
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. This suggests IoT may help reduce carbon emissions and energy use over time.
Ultimately it is hard to predict the long-term effects of the IoT. Research into its broader effect on energy use face 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?
Rapid digitalisation and ongoing increases in data traffic presents significant opportunities to support the system changes needed to transition to ultra-low carbon economies from more accurate climate modelling and energy services to supporting smarter cities and home working. However, the growth in data raises questions about how the carbon footprint of ICT could change in the future, particularly with the building of larger data centres and the launch of new communications networks. 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 actual data from recent years, the electricity consumption and carbon footprint of the ICT sector does not follow the same trends as data traffic. Since 2010, total data traffic has increased approximately tenfold, while electricity consumption for the ICT sector has increased by less than 10 per cent.
Looking specifically at data centres, studies show while computing output from data centres went up six-fold from 2010 to 2018 electricity use increased up 6 per cent.
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.
Arguments that the ICT industry will consume most of the world’s electricity within a couple of decades are, therefore, unreasonable (as well as far too expensive to support).
Yes, the sector is seeking to offset its impact: and it is a trend that has positive system-wide benefits.
ICT companies are major investors in renewable energy and hold themselves strongly to the principle of additionality; enabling the development of renewable energy projects that would not have occurred without company’s commitment to buy the off-taker for the project. This purchasing has also helped scale renewable energy, which has reduced the costs of renewable energy, developed new markets for renewables, and expanded renewable energy into regions that might have lagged without corporate purchasing pressure.
This trend has now spread into other sectors, but ICT remains a key player in the market. Data centre developers and network operators are increasingly sourcing renewable electricity, like wind or solar, with some making long-term contracts (PPAs) with developers to build power plants that otherwise would not be built. Companies also buy renewable electricity on the market by purchasing Renewable Energy Guarantee of Origin certificates to match their energy demand.
The top six corporate ‘off-takers’ of renewables in 2018 were all ICT companies; the sector is the largest global purchaser of Power Purchase Agreements (PPAs), and was by far the largest investor/purchaser of renewable electricity.
In a study of global telecom operator energy and carbon footprint performance for the period of 2010 – 2015, the share of renewable electricity reached about 46 per cent. A later, not yet published ETNO study for the period 2015 – 2018 focusing on EU based telecom operators, calculated that the share of renewable electricity was about 74 per cent.
In the case of PPAs, which are common in places like the USA, the renewable energy power plants are sized to generate at least as much electricity as the data centre would use over the course of a year, and in that annual sense, they are powering their data centres using clean electricity. In the UK, there is potential to consider how to unlock the PPA market, so PPAs are more accessible to companies that are keen to invest in them (see: techUK Data Centre Energy Routemap).
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.
In the UK, users tend to retain mobile phones for two years before replacing them. This reflects mobile phone contracts that run for two years before users are offered an opportunity to upgrade their phones. Recently this has been challenged by ‘SIM-only’ contracts and consumer reluctance to accept long binding periods.
However, the lifespan of a mobile phone can be as long as eight years. After upgrade, around 8 per cent of handsets are either sold or returned and enter a vibrant second-hand market. The remainder are likely hoarded at home or gifted to friends and family.
Manufacturers are motivated to ensure mobiles are repairable and durable to minimise warranty costs. The focus has been primarily on preventing dust ingress and water damage, underpinned by international standards.
Other circular economy models have been explored. Some OEMs 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.
The European Commission is currently exploring what eco-design measures can be introduced to further support phone’s longevity and has recently announced plans to introduce an EU-wide take back scheme. The UK is also considering options as part of its approach to extended producer responsibility. Indeed, improving a products’ ability to repair and upgrade and its durability is a big focus of current EU and UK efforts on product design. Last year, for example, it introduced new rules requiring manufacturers of certain products to ensure spare parts are available for seven years and to provide repair information to professional repairers. It is also expected to introduce a new ‘right to repair’ in consumer law.
In several articles and papers, the assumed annual growth of the sector’s carbon footprint has been described as high and increasing, mostly based on the assumption that the sector’s carbon footprint and energy consumption is growing in line with exponential data increase. Estimates like these are usually based on limited and/or uncertain data, often of a certain age, that overstates ICT’s footprint.
There are other complexities that make numbers hard to derive and compare studies in this area, which include:
Therefore, in-depth studies and extensive data sets using large samples of measured data are needed to create a better understanding of the sector. Further, these need to be repeated relatively frequently. Until now there have been only a few studies published that are based on actual data and trends and not only modelling, and these studies tell a very different story compared to the extreme figures that are often mentioned.