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Energy Consumption
The Internet as an energy guzzler

Globally, data centres are responsible for a third of the energy requirements of the Internet.
Globally, data centres are responsible for a third of the energy requirements of the Internet. | Photo (detail): © Adobe

Having your own mug for a takeaway coffee or not using the plastic bags at a supermarket – such examples of environmental awareness and personal responsibility have now become part of everyday life for many Germans. However, it is (still) a very small number of people who question whether each individual search query or the sending of every photo on the Internet is really necessary – this, too, can actually be environmentally harmful.

By Arne Cypionka

Is using the Internet harmful to the environment? To say the least, it is most certainly energy-intensive, and by far exceeds the power consumption of your own laptop or smart phone. Even if we hardly waste any time thinking about it when we stream a series or surf the Net. Data transfer is only made possible by a complex infrastructure of transmission towers, internet nodes and data centres. These consume large amounts of energy at times, and since the amount of data transmitted on the Internet is constantly increasing – by around 30 per cent each year, the amount of energy required to enable people to use the Internet is also growing.

For example, a single Google search, the company said in 2009, consumed 0.3 watt-hours. This corresponds to a 60-watt light bulb that lights up for 18 seconds. It was estimated in 2018 that there were approximately 50,000 Google searches – per second. If you add the consumption of the company’s other products, such as the 400 hours of video material that are uploaded to YouTube every minute, the result is a consumption of 10.6 terawatt hours for the year 2018. This is already almost as much as the electricity consumption of a big city like Hamburg (11.9 TWh in 2018).

And even though Google is one of the largest IT companies in the world, it still does not meet the demands of the entire Internet. According to estimates, only one to five percent of the Internet’s total electricity consumption can be attributed to the company. So what are the options for making the Internet more energy efficient?

Greener data centres

Researchers have identified three areas of Internet use that all consume approximately the same amount of energy: In addition to the network infrastructure and end devices such as laptops and smart phones with which we access the Internet, it is primarily the running of data centres. These are large halls full of servers that fill the Net with content. They make all kinds of activities possible: internet searches, cloud backups, social media, music streaming and much more. In addition to the energy supply for the computers themselves, the cooling of the rooms also consumes a lot of electricity because the systems generate vast amounts of waste heat.
This is exactly where technologies come into play – technologies that want to make data centres more ecological. So-called waste heat utilization is used to try to produce new energy from the waste heat emanating from the computers. For example, the computers are cooled with water, which heats up and turns into a source of energy itself. In this way, either the hot water requirements of the data centre can be covered autonomously or even part of the energy required for cooling can be saved. For the latter, the energy from the hot water is processed by an adsorption chiller to generate cooling capacity. In Sweden, some of the waste heat from the data centres is fed directly into the district heating network and used to heat residential buildings. Swimming pools or greenhouses also benefit from district heating.

In Germany, the amount of electricity that could potentially be saved is huge – 13 terawatt hours are converted into heat in Germany’s data centres which is then emitted into the environment almost completely unused. This is as much as Berlin’ annual electricity consumption. In Germany, however, the utilisation of waste heat produced by data centres is paradoxically spreading rather sluggishly, even though German companies are world leaders in technology. According to studies, this can be mainly traced back to a lack of experience, comprehensive concepts and funding programs. Nevertheless, the majority of German data centre operators see great potential in the use of the technology and at least a quarter of the operators plan to install a waste heat utilisation plant the next time they modernise their premises. In addition to this increase in efficiency, the use of renewable energy sources in the data centres is also an important topic. When it comes to renewable energies things are actually looking much better in Germany – almost 30 percent of data centre operators state that they rely entirely on renewable energies.

On a political level, data centres that are more environmentally friendly are most definitely welcome. Since 2015 data centres have been eligible for the “Blauer Engel” (Blue Angel), the Federal Government’s eco-label. It is awarded to data centres that work in an energy-efficient manner, use regenerative energies and ensure a high degree of capacity utilization. So far, however, only a few isolated centres have acquired the certificate.

Energy efficiency does not compensate for increasing consumption

The increasing use of the Internet has also led to the construction of numerous new data centres in Germany and this is most likely to continue in the near future. With greater networking and new, data-hungry applications, such as self-driving cars, the amount of data and energy consumed will continue to grow.

Despite all the efforts made to improve the environmental friendliness of the IT sector, studies have so far shown one trend above all – although data centres, computers and smart phones are becoming increasingly energy-efficient, this saving cannot yet compensate for the additional energy consumption caused by the growth of the Internet. This is why it is all the more important that the environmental compatibility of digitization should become a more relevant, larger issue in the public eye. The potential increases in data centre efficiency, such as the utilisation of waste heat, could make a significant difference if they were approached more consistently. And maybe some people would even stop and think for a moment before they once again succumb to the temptation of sending a photo of a dinner party to all their friends.