Green IT | Umweltbundesamt

Much of what we once had to physically move from one place to another, including ourselves, or processing material is now possible virtually and thus seems to have become intangible. Examples: photographs are in the cloud instead of in a photo album, we write an email or chat message instead of a letter, or we meet in video conferences instead of travelling to a face-to-face appointment. Mobile transmission networks, the landline network and data centres have long been part of the critical infrastructure, because they ensure e.g. that energy and water supplies are secure. But behind every digital and virtual application lies a very real demand for raw materials and energy. That demand also contributes to climate change and degradation of the environment. Photos "in the cloud" are stored in a data centre. The server in this data centre first had to be manufactured and needs electricity to operate and for air conditioning. The same applies to video conferencing, e-mail and everything else digital. The desktop notebook and the smartphone in one’s pocket were also produced at considerable cost in terms of raw materials, energy and emissions.

How big is the actual demand for raw materials and energy?

There is little data available about this so far, and its quality is often poor. For example: estimates of the global energy demand of data centres for 2020 range anywhere from 200 to 1,000 terawatt hours (TWh). (By way of comparison: Germany generated a total of around 500 TWh of electricity in 2020 which was fed into the grid). Data can differ by a factor of five, depending on the study.

This high level of uncertainty means that neither efficiency potentials nor adverse developments are easy to identify and thus complicates environmental policy in this sector. UBA is working to improve the data situation.

How can green IT help to make digitalisation resource- and energy-efficient?

Hardware such as notebooks, smartphones or desktop computers should be used as long as possible because most of the climate-damaging emissions in the lifecycle of e.g. a notebook are generated in its production. Imagine, for example, you want to purchase a new, economical notebook. Although when in use it is more energy-efficient than one’s old appliance, thus saving carbon dioxide emissions, it would nevertheless take several decades to pay off the cost of production.

Software, although it is non-tangible, has a major impact on how much electricity hardware uses and how long it can be used.

Computer centres play an intrinsic role in digitalisation. Without data centres, there would be no cloud applications, no streaming, no video conferencing, no communication via email or messenger - in short: no internet. Data centres consume considerable amounts of electricity. About a fifth of Frankfurt am Main's electricity consumption, for example, goes to the account of the city-based data centres.

Transmission networks, together with data centres, make up the internet. There is no digitalisation without data transmission, whether it is a fibre-optic network, copper cable or mobile communications. Our research focuses on how data transmission can be made more climate- and resource-friendly.

Digital services such as video streaming, videoconferencing or cloud data storage are becoming increasingly popular. A research project by the German Environment Agency has focused on the volume of CO₂ emissions of digital services.