The CO₂ emissions from manufacturing and use of digital devices (laptops, phones, tablets, TVs, ...) are huge and rising steeply. Here is what you as a consumer can do to help reduce your digital carbon footprint.
- The current CO₂ emissions from the internet and digital devices form about 2% of the world CO₂ emissions but are expected to rise steeply over the next two decades. By 2040 this "digital carbon footprint" alone will make up more than half of the acceptable global carbon footprint to keep global warming below 1.5°C. So the growth in digital carbon footprint is unsustainable: it would make it virtually impossible to keep global warming below the safe limit.
- What is little known is that the CO₂ emissions from production of digital devices exceed the emissions from the electricity they use over their lifetime. So even if newer devices are more energy efficient, producing more of them will make the emissions problem worse.
- Apart from the carbon footprint of production and energy consumption of our digital devices, their main purpose — accessing the internet — also causes increasing amounts of CO₂ emissions. As an end user, you only have direct control over a small fraction of this: the energy consumption of your home (or office etc) network. The core network consumes a huge amount of energy but it does this regardless of how much data you transfer. But there is indirect consumer control: if we collectively use more and more data, the network operators have to install additional capacity. Conversely, if we collectively used a lot less data, some of the networking infrastructure could be powered down and even decommissioned. So it still makes sense to be frugal with your internet data.
The solution — what you as a consumer can do:
- Buy fewer new devices (laptop/desktop/phone/tablet/TV):
- Keep using your existing devices for as long as possible.
- Have your devices repaired rather than replacing them.
- Only buy devices you really need.
- When you use your devices, use them as little as possible and in the most energy-efficient manner:
- Reduce your internet usage.
- Reduce your resolution when watching streaming video.
- Turn off your camera in online meetings.
Buy fewer new devices
The CO₂ emissions from production of digital devices far exceeds the emissions from the electricity they use. Therefore the best possible action from a consumer perspective is not to buy new devices.
For digital devices such as mobile phones, tablets, laptops, desktop computers and televisions, the carbon footprint from manufacturing is so large that no amount of energy efficiency savings during use can compensate for it. So buying a new device effectively results in more emissions, even if it is a more energy-efficient model. It is better to keep using an older device for longer, even if it less energy-efficient. For the same reason it is better to have your devices repaired than to replace them.
Companies are starting to realise that increasing numbers of consumers want to use their devices for longer. Apple has recently introduced a repair self-service and several brands of Android phones have started to offer up to four years of support on some models.
When you use your devices, use them frugally
The internet network infrastructure also generates huge amounts of CO₂ emissions. This is the "invisible" carbon footprint of the physical infrastructure required to serve, store and transfer video, voice and data.
As an end user, you only have direct control over a small fraction of this: the energy consumption of your home (or office etc) network. The core network consumes a huge amount of energy but it does this regardless of how much data you transfer. But there is indirect consumer control: if we collectively use more and more data, the network operators have to install additional capacity. Conversely, if we collectively used a lot less data, some of the networking infrastructure could be powered down and even decommissioned. So it still makes sense to be frugal with your internet data. The same argument holds for cloud storage: manufacturing storage devices has a huge carbon footprint. If we collectively store less data in the cloud, fewer storage devices are needed, and that reduces emissions.
- For video calls, the most effective action is to switch off your camera whenever possible, even if this does not save a lot of energy in the immediate sense.
- For watching streaming video (including TV), reducing the resolution has a similar effect.
- When you use a search engine or browse the web you also increase your footprint. Search requires a lot of storage hardware as well as compute power to calculate the ranking of results. The cost of browsing the web is also high in an less intuitive way: the machinery for brokering and serving ads and tracking user behaviour requires a lot of compute power.
In a nutshell, the key actions you can take to reduce your digital carbon footprint are to buy fewer new devices, keep using your existing devices for as long as possible and only buy devices you really need: this reduces the carbon footprint of manufacturing. And when using your device, the most effective action is to be frugal: reduce your internet usage, reduce the resolution when watching streaming video and turn off your camera in video calls. Store as little data as possible, especially in the cloud.
Postscript: video calls are still better than cars, even electric ones
Even with your camera on, it is still better to have a video conference than to drive to a face-to-face meeting. Assuming average estimates for the emissions from internet usage and car journeys, driving just 500 m causes the same emissions as a video call of one hour. And it might come as a surprise that even if you drive a new electric car, that distance only increases to 1 km.
[Note: post edited on 2022-12-07 because the original post assumed that internet network emissions are proportional to the traffic volume, and more recent research shows this is not the case.]