
Subject and objectives of the study
The current study – status as of June 2025 – models the environmental impacts of the production and use of ICT over a period from 2010 to 2036. The energy and resource requirements for the manufacture of ICT used in Germany are calculated as a carbon footprint, reflecting the global supply chain. For the energy-intensive usage phase, both the electricity demand and the carbon footprint are quantified depending on the annually changing energy mix.
The data model developed by Fraunhofer IZM for quantifying the environmental impact of ICT covers key application areas and product categories, including ICT in households, at work, in public spaces, in data centers, and in telecommunications networks. Due to limited public data, ICT used in industrial production, agriculture, logistics, mobility, and transportation, as well as in the areas of energy and building control, could not be modeled.
Rising energy demand and carbon footprint in the use of ICT
The total annual electricity demand of ICT in Germany has grown from around 46.5 TWh in 2015 to 54.4 TWh in 2025. The modeled forecast shows a further increase to around 75.5 TWh in 2035. Data centers are the primary contributors to this increase.
The share of data centers in the total electricity demand of ICT has been growing significantly for several years. In 2015, data center electricity demand was still 14.1 TWh, which corresponded to a 30% share of total ICT-related electricity consumption. By 2025, electricity demand will have increased to 25.9 TWh per year, accounting for 47.6% of total ICT electricity consumption. The forecast for 2035 shows a further increase to 41.3 TWh, which would correspond to 54.7% of total ICT electricity demand. This makes data centers the largest driver of ICT electricity demand in Germany.
The cloud-based demand for data processing, storage, and transmission is increasing with advancing digitalization. Virtual worlds and artificial intelligence are keeping the increase in data volume constant. And even though existing IT systems are being better utilized, cooling and power supply infrastructures are being optimized, and technical progress in the fields of microelectronics and photonics is continuing, the trend can no longer be offset as it was in the past, and the power requirements of data centers will therefore increase significantly in the medium term.
ICT in households represents the second largest area of application in terms of electricity consumption. This category comprises 36 product groups, including smartphones, personal computers (PCs), televisions, and home routers. In 2015, ICT in households accounted for 22.2 TWh, or just under 47.7% of total ICT electricity demand.
These products underwent significant technical improvements during the same period, which are also linked to consistent European legal requirements for maximum power consumption. As a result, electricity demand fell significantly in the following years and will reach 17.1 TWh in 2025, corresponding to a share of only 31.4%.
In the medium term, however, the electricity demand of ICT in households will rise again. This trend is due in particular to the significant power consumption of large televisions and network technology in the home environment. A value of 21.8 TWh is forecast for 2035, which corresponds to a constant share of 28.9%.
The areas of application for ICT in the workplace and in public spaces have remained largely constant since 2015, at an average of 7 TWh and 0.5 TWh respectively, and are also expected to show only minor changes in the forecast up to 2035.
There is a certain degree of uncertainty in both forecasts, as public data used to determine the current situation appears to be somewhat contradictory. The declining sales figures suggest that devices are now being used for several years longer than they were ten years ago. A reasonable assumption in this context is that the functional and technological maturity of PCs, displays, and communication technology is contributing to their longer service life.
The electricity demand of telecommunications networks has been rising slightly for years. In recent years, there has been a significant increase from around 2.7 TWh in 2015 (if the analog/ISDN network that still existed at that time is included, the figure would be around 3.5 TWh) to 4.8 TWh in 2025. The forecast predicts only a slight further increase to 6.0 TWh in 2035 in the medium term.
The expansion of mobile communications networks and the switch to new mobile communications standards have been the drivers of growing electricity demand in recent years. However, more modern technologies and system architectures generally improve energy efficiency. As a result, despite the increasing volume of data transmitted via the networks, electricity demand is likely to increase only moderately in the coming years as the networks are continuously modernized.