"The IT sector has a problematic growth rate"
Watching videos on YouTube and various streaming services accounts for an increasing share of the world's energy consumption. But what is really the carbon footprint of our online activities? Mike Hazas, Professor of Human-Computer Interaction, clarifies the concepts.
Technology. Photo: Mikael Wallerstedt
“Today, the IT sector accounts for about three percent of global carbon emissions, roughly equivalent to the aviation industry. That may sound acceptable, but the problem with IT is its rate of growth. Global network traffic has been growing by about 30 percent a year, and the number of digital devices is growing by ten percent a year. The growth in IT’s carbon emissions is harder to calculate, but it is important to study and estimate it, rather than simply let the sector grow ’organically’ as it has done so far.
“In Sweden, we produce electricity with a higher proportion of renewable energy than in many parts of the world. So, our local carbon footprint from internet use is likely to be relatively small. On the other hand, we are part of a global digital ecosystem, with manufacturers and data centres that are still dependent on fossil fuels.”
Which of our online behaviours consume the most energy?
“In general, any activity that involves a large video screen, or a machine that gets warm, will consume more energy. Video streaming alone accounts for about three percent of electricity use in Sweden and globally. YouTube accounts for half of all video traffic. At least nine percent of internet traffic is gaming-related. There, different types of games have different environmental impacts. Large consoles such as the PlayStation 5 or Xbox Series X are manufactured far away and contain many minerals, which is much more carbon-intensive to produce. They also draw more power than laptops and most smart TVs.”
Is there an awareness of this?
“I think awareness is still relatively low. I think we should establish a dialogue in society, about how we should value different online services and devices from an energy or environmental point of view. Because you can't start saying whether the growth ‘is too much’ or the manufacturing ‘is not worth it’ without knowing what benefits it brings to people. And it can take years to find that out!”
How does your research work?
“I conduct studies by measuring network traffic, and observing what online services and devices are used, when and for how long. I tie this analysis to energy and carbon emission estimates, based on recent research in life cycle assessment. In the past, with research colleagues in the UK, I have mapped network usage in English households using network logging, time use diaries and interviews, and so on. I am now planning a similar research project in Sweden.”
What can we consider if we want to reduce our environmental impact?
“Some advice includes downloading fewer videos, and not using video streaming as background noise. It's also a good idea to disable background processes on mobile and social media. Turn off automatic app updates and cloud service backups. However, streaming audio on Spotify and other audio media is not so energy-consuming. But above all, don't get new devices too often! Keeping your digital devices for as long as you can is many times more efficient than anything else you do.”
Anneli Björkman