Why does CO2 cause pollution

Is Netflix Bad for the Environment? How video streaming is fueling climate change

Dozens of e-mails a day, a call via WhatsApp, saving photos in the cloud, briefly watching a video on YouTube - all of this is part of everyday digital life almost all over the world. For each individual it is "just a photo", it is "only a few minutes of video", but all in all, our internet behavior causes enormous climate effects.

Because every computing activity requires electricity. And the generation of electricity, which mainly still uses fossil fuels, generates CO2.

The use of digital technologies has even overtaken the aviation industry in terms of CO2 emissions. While the share of air traffic in global CO2 emissions is estimated to be around 2.5 percent (and rising), almost four percent of all CO2 emissions are now due to global data transfer and its infrastructure, like the French think tank "The Shift Project" set out in its most recent study. The non-profit organization is researching ways to an economy that works with renewable energy.

Digital everyday life with enormous energy requirements

The sum it calculates includes both the energy costs for the IT infrastructure and for the actual data usage - and the latter consumes more electricity than the production of all devices and technology combined.

According to a projection by the IT giant Cisco, 60 percent of the world's population will be using the Internet by 2022. And global data transfer is growing: by more than 25 percent per year, Cisco predicts. Therefore, one urgently needs to think about the future of Internet use, says Maxime Efoui-Hess of "The Shift Project". The energy and environmental engineer contributed significantly to the latest study of "The Shift Project". His conclusion: we urgently need to be more "digital modesty" again.

Digital technology has become an indispensable part of everyday life, but we have to rethink, according to the study by "The Shift Project"

"We only have limited energy resources. Even if we switch to renewable energies now, we cannot assume that they will prevail everywhere in the next ten years," the author of the study points out. The internet works through global networking. For a "purely green" data transfer, every country on earth would only have to use renewable energies. But that is not foreseeable. "That is why global data transfer must not continue to grow as rapidly as before," said Efoui-Hess.

300 million tons of CO2 through online videos

The majority of this data is now made up by videos: 80 percent of all data rushes through the network as moving images. Almost 60 percent of global data transfer is online video. This includes videos that are stored on a server, viewed on separate end devices without prior download and made available by platforms that can be accessed via the Internet.

The problem: moving images require huge amounts of data. The average CO2 consumption through such online videos is more than 300 million tons per year (measurement period 2018). This is roughly the amount that all of Spain emits in one year. The higher the resolution, the more data is required. According to "The Shift Project", ten hours of HD film require more bits and bytes than all the articles in the Internet encyclopedia Wikipedia put together.

The problem is our brain

The way we consume videos and films has fundamentally changed. While films used to convey a story with moving images and music, videos on the Internet are primarily used to capture the attention of users and keep them on the respective page for as long as possible. "It works wonderfully because our brain is geared towards moving pictures. We look immediately when something moves. That is why more and more moving pictures are being linked on the Internet: music, information, advertising," says Efoui-Hess.

Our brain loves films - streaming providers and internet platforms make use of this

In the meantime, platforms such as YouTube, Facebook, Netflix and Co are using this preference in an increasingly sophisticated way, reports Efoui-Hess. "For example with the autoplay function, which lets videos start running without having to start them manually. Or with subtitles. This makes information even easier to consume and the user watches the film right through to the end in most cases."

"The last mile is crucial"

Can the hunger for video be satisfied in a more energy-efficient way? Or do you have to do without your favorite online series altogether? In any case, it is better to watch a program on analog television than on a live stream or in the media library, says Efoui-Hess. The analogue broadcast also consumes electricity, but here the data is only transmitted nationally instead of halfway around the world, as is often the case with Internet videos.

Mobile phone CO2 sling: In mobile communications, data transmission costs a lot of energy

Lutz Stobbe also confirms how important the transport route is for electricity consumption. At the Fraunhofer Institute for Microelectronics and Reliability in Berlin, he is researching the environmental impact of information and telecommunications technology. The so-called last mile is particularly crucial, i.e. the question of which technology is used to get the data to the user.

Most of all electricity is consumed in a cellular network transmission. Open space attenuation, buildings, vegetation and weather weakened the electromagnetic waves and led to losses. Therefore, a high transmission power is necessary. But the signal also has to be amplified with the old copper cables, especially over long distances. "The power amplifiers have a low degree of electrical efficiency. As a result, around half of the energy used for data transmission is lost as heat. The most efficient transmission technology is clearly fiber optic cables that transmit the signals by light."

5G instead of fiber

Germany, for example, still mainly surfs the Internet with copper cables. Only slightly more than two percent of all broadband connections consist of fiber optics (as of 2017). Mobile communications, on the other hand, are being massively expanded.

After all: According to Stobbe, work is currently being carried out on what is known as edge computing, i.e. on storing the requested data closer to the end customer, for example in data centers in large cities, instead of sending it far across the country.

The technology is exhausted

Hoping for new devices and technologies that could operate in a more energy-saving and therefore more climate-friendly manner would, however, be of no use. The energy efficiency of technical devices has not changed significantly in the past ten years, says Stobbe. This is another reason why you should use your old devices for as long as possible.

The power consumption of IT technology has not changed significantly in the past ten years

What remains, however, are small adjusting screws that each individual can turn. "We call this digital hygiene. Do you really have to upload 25 images of the same motif to the cloud? Every saved photo, every saved video is saved there again and again for security reasons, and that consumes energy every time extinguishes, you save energy. "

Read more: Tips on digitally saving electricity (Source: Federal Environment Agency)

"The digital CO2 emissions must be on the agenda"

Maxime Efoui-Hess also knows such adjusting screws: "A lower video resolution always saves data and thus electricity. A smartphone, for example, cannot display an HD resolution at all." In addition, the bigger the screen, for example on a smart TV in the living room, the higher the power consumption. Conclusion: Watching HD films on your smartphone via the mobile network is the most energy-intensive and therefore the most harmful to the climate.

"The Shift Project" has developed a CO2 calculator for the browser in order to create awareness of the climate impact of everyday digital life. It measures the CO2 emissions caused by one's own internet activity. However, the organization does not see the user as the sole responsibility. The question of a more climate-friendly Internet, and thus above all of the future handling of moving images on the Internet, is of such great relevance that it has to be put high on the political agenda, according to the conclusion of their study. But so far, neither governments nor international institutions have recognized the issue as a problem, let alone taken it up.