Mis à jour le 28 September 2022.
Energy usage has been a hot topic for the past few years and the Russian-Ukrainian war has made the matter even more relevant. Is our way of consuming culture via streaming services to be questioned? Could it be made more efficient? This depends on several factors, including how the country (where the data center and user are located) produces its energy (its energy mix) and the way we consume media (a TV uses a lot more electricity than a smartphone). It’s also important to note that data transmission is energy consuming and must be accounted for as well.
Since the mid-2010s with the rise of YouTube and the arrival of streaming platforms such as Netflix, energy experts of all stripes have been studying the energy consumption of this practice. The method of calculation itself is a source of debate among researchers of different ideologies, each wanting to defend their theory. The most serious studies on which numerous articles are based all converge towards the same conclusion and the variations, which can be significant, are caused mainly by the application of an ideology rather than by the figures. Video streaming, online gaming, video conferencing and emerging technologies represent around 80% of the global bandwidth and, in the future, will likely increase the demand for data centers and networks. But how much energy does all this use?
The three types of streaming energy use
Hosting/data center energy usage
Improving energy efficiency helps limit the increase in energy demand. Data centers are multiplying around the world, yet the average energy use of a data center is declining every year and continues to be more than offset by ongoing improvements in the efficiency of servers, storage devices, network switches and infrastructures, as well as the high and growing number of services provided by highly efficient cloud and hyperscale data centers.
Cloud and hyperscale data centers work at high capacity, partly thanks to virtualization software that allows data center operators to provide higher performance with fewer servers. Moreover, these large data centers typically have very low power usage effectiveness (PUE) ratios, which is a measure of how efficiently a data center uses energy. The most efficient hyperscale data centers can have PUE ratios of approximately 1.1 (which means that 0.1kWh is used for cooling/energy supply for every 1kWh used for IT equipment. Some are continuing in this direction by sending the water heated by the cooling systems to district heating networks. The number of initiatives is increasing and the application of these ideas is likely to become more commonplace.
Transmission energy usage
Globally, the entirety of data transmission networks used 260 to 340TWh in 2020, which is 1.1 to 1.4% of global electricity usage. This figure takes into account all transmissions, of which streaming is only a small part. To give you a rough idea of what this represents, it is approximately five times less than the energy used by the global steel and iron industry, but it is also the same as the entire annual production of France’s nuclear plants. This means that France’s nuclear energy consumption represents 1.1 to 1.4 percent of the world’s electricity consumption.
Data transmission network technologies are becoming more efficient. The global internet traffic, which more than doubled from 2017 to 2020, could double again by 2023 if current trends are sustained. The type of data transmission is changing rapidly, with the traffic from portable devices growing three times faster (+50%) than that from wired and WiFi devices, such as laptops and desktop computers (+17%).
This trend toward greater use of mobile networks may also have significant implications for the energy consumption of data networks, due to the fact that mobile networks have significantly higher electrical intensities (kWh/GB) than fixed networks at current levels of traffic and network usage.
By the end of 2022, 4G and 5G networks are expected to collectively handle about 83 percent of mobile traffic, compared to less than 1 percent for 2G. 4G networks are about five times more energy efficient than 3G networks and 50 times more efficient than 2G networks. Infrastructure and network suppliers have predicted that 5G networks could be 10 to 20 times more energy efficient than 4G networks by 2025-2030.
Consumer energy usage
As consumers, we can further reduce our environmental footprint by opting for smaller devices and screens that use less electricity. It also helps to look closely at the energy label and repairability index of products and to replace devices less often, as the production phase accounts for about 80% of the carbon emissions of mobile devices during their lifespan (about a third for TVs) and because e-waste is a growing problem around the world.
Another recommendation is to not watch videos if you simply want to listen to a file. The giant YouTube has a lot of work to do on this front given its position as world leader and its inability to disable the video file if it only contains audio. Some experts suggest improving compression systems, others simply advise watching videos in a lower resolution, even if this also changes the sound quality (something else to be improved). Moreover, watching a video on a mobile device uses a lot less energy than on a 4K television. However, this statement should be taken with a pinch of salt, because CO2 emissions are also related to the manufacturing and the transport of audiovisual equipment, the information received from online services as well as the electricity consumption in the user’s home.
Energy mix by region
Differences in electricity production can make the numbers vary drastically. Consequently, a recent study commissioned by Le Temps (Swiss newspaper) and carried out by Carbon Trust in 2021 showed that in Sweden, streaming an hour-long video produces “only 3g of CO2 compared to 10g in France and 76g in Germany”. But it can also depend on the way in which the information is transmitted (streaming, for example). As mentioned earlier, “faster networks produce less CO2”. That is “2g an hour for fiber optic, 4g for standard copper lines, 5g for 5G, 13g for 4G and 90g for 3G”.
This is due to the act that each country generates its electricity differently. France, which uses nuclear power, generates approximately 8 times less CO2 than Germany for its electricity production, but almost 5 times more than Sweden. With only 1.4% of fossil fuels in its energy mix, the Scandinavian country proves that a country’s energy mix can influence how “guilty” a user feels when streaming a 4K movie.
While each country must continue its efforts to decarbonize its energy mix, the world average in relation to a given service should be prioritized if we want to make relevant comparisons (climate change concerns all countries). According to the IEA (International Energy Agency), it is generally more eco-friendly to watch a movie at home than driving to the movie theater. By way of comparison, on average in Europe, the carbon footprint of streaming a video for one hour is equivalent to driving 250 meters in a car.
Data center firms and major internet companies are among the biggest investors in renewable energy and future technologies designed to reduce CO2 emissions. These corporations and global economic behemoths are investing massively in renewable energy for purely economic purposes: to stabilize the cost per kW/hour, which can vary widely as recent events have shown.
The increase in the use of streaming services since COVID
According to the ITU (the United Nations’ International Telecommunications Union), internet usage increased by 10.2% in 2020 during the first year of the pandemic with 4.6 billion users, before reaching 4.9 billion in 2021. While the use of streaming services is one factor in this increase, data center usage has, according to SDCIM (a data center software company), jumped 775% at Microsoft, 1000% in audio/video/message exchanges at Facebook, with 700% more VPN users. Concerning Netflix, the two countries that were the most impacted by Covid, Italy and Spain, saw users rise by 57% and 34% respectively. The internet traffic rate saw a new peak of 9.1 terabits of data exchanged per second! Looking at these figures, one would have thought that the resources to run these data centers would be stretched to the limit, but streams were not particularly impacted. The resilience of the network is therefore strong and ready to respond in case of important demand.
The responsibility of key players in this sector
All sectors and technologies are needed to meet the targets of the Paris Agreement. Digital technologies are no exception. In fact, digital technologies such as Artificial Intelligence could help reduce climate change. But in the absence of meaningful climate policies, AI may allow oil extraction to become cheaper or it could be used to extend the lifespan of coal-fired plants. The ideologies and constraints of world leaders are inextricably linked to consumers’ daily carbon footprints.
There is no denying that data center usage is increasing every day and that it is essential to closely monitor the exponential growth of streaming services and other digital technologies so that we can continue to enjoy the benefits while reducing the negative consequences ‒ particularly concerning electricity usage and carbon emissions. The electricity usage of these centers is fairly stable, thanks to process innovations that are absorbing the additional energy demand and increasing investments in renewable energy. Instead of relying on sometimes deceptive media coverage, achieving the goals of the Paris Agreement will require rigorous analysis, real business leadership and sound policies aligned with well-informed citizens.
If all economic participants made as much effort as companies in the online services sector regarding environmentally responsible investments, perhaps the overall situation would be a little less concerning. Efforts on the part of consumers can also help to achieve a certain degree of energy responsibility. Keep in mind that if there is no demand from consumers for a product or service, companies are likely to rethink and withdraw their offer from the market.
There are other, less obvious effects that may still tip the balance, as we mentioned in the article: Matt Damon is worried about the end of DVD and Blu-ray, “Recently, HBO Max removed more than 37 programs, including many originals that can’t be found anywhere else.” Understandably, movie lovers and Matt Damon will always have a hard time accepting that market law should decide which movie should vanish.
Cultural media isn’t a threat to the planet
It is clear that data centers and movie streaming won’t be the cause of the power cuts announced for this winter by our governments. It is also difficult to blame the data centers that have multiplied tenfold in recent years as they don’t consume more energy than before. It is also hard to criticize the sector’s giants due to their massive investments in renewable energy. They can be accused of “buying” their eco-friendly badge, but the same can’t be said for other industries that consume much more energy.
Unless you hate movies, and taking into account that it is responsible for approximately 1-3% of total global energy consumption, it wouldn’t be a terrible thing for cultural media transmission to use a little more energy, especially if the energy mix of countries becomes a little greener. The global pandemic reminded us just how important it is in our daily lives. We should also keep in mind that digital technologies are excellent educational tools, that data centers also preserve books and archives from all over the world, all the scientific articles and reports that have been written on the subject, that data transmission also allows you to call your loved ones and many other things that are simply beneficial for the whole of humanity.
It is up to consumers to avoid watching videos of cats on their 8K TVs with Dolby Atmos surround sound. As citizens, it is up to us to be aware of our daily screen time, to favor the purchase of high quality equipment with a high repairability rating when possible, to use second-hand equipment (check out our partner AV-Market.com), or to use low energy consumption viewing devices for trivial content… Isn’t this just common sense?
Sources: IEA, Carbon Trust, ITU, Malmodin, US Department of Energy