Yes, really. If you work long hours on a laptop or desktop computer, like we do, then your power usage contributes to global warming. Admittedly, it does so in rather small amounts compared to the big offenders like fossil fuel extraction industries and transport. But this summer’s heat waves got us thinking - how culpable are we? So we started digging into the numbers on emissions from the IT industry.
Turns out, all this also has a very topical energy cost angle. So read on for some tips on not only minimising your carbon footprint, but also saving some money on your energy bills.
(A little note on the side: To keep the scope of this blog post manageable, we have limited ourselves to three broad areas. There is much more nuance to this topic, of course, and we also chose to omit certain areas entirely. For instance, much has been written about the carbon cost of crypto currency in recent years, but we decided not to include this topic here.)
Let’s dig in!
Increasingly being used for work, smartphones are expected to generate over 140 million tons of CO2 or CO2 equivalent emissions in 2022. If you think that is big, read this: that figure is less than half a percentage point (< 0.5%) of the total CO2 emissions generated in 2021 - a whopping 34 gigatons. Both of these stats are from Deloitte (1), which also states that the vast majority of emissions are generated during manufacturing and shipping, nominally the first year of a device’s lifecycle. Speaking of lifecycles, these tend to be on average between 2-5 years for modern devices (2). 85 kilos of Co2 are generated per smartphone in its first year alone, and much of that depends on factors such as production materials used in the device and the energy efficiency of the manufacturers’ facilities.
This may all sound fairly innocuous, but honestmobile.co.uk has a great calculation that illustrates all this more tangibly. They estimate 70 kg of CO2 emissions annually:
“The average person in the UK is expected to live to the age of 81, and the average child gets their first phone at the age of 10. So, the average Brit has a phone for about 71 years which equates to 4,970kg of CO2. That’s equivalent to flying from London to New York 7.5 times.” (3)
They continue, pointing out that using one’s phone requires them to be charged frequently and to run services that require energy-intensive infrastructure (e.g. servers and data centres). All this adds up, and simply texting, calling and posting your snaps on Instagram or similar platforms generates about 17kg of CO2 per year per phone (4).
German manufacturer Viessman goes further yet, stating in a 2019 report that using a smartphone one hour each day for a year generates 1.25 tons of CO2 - that’s about the same amount of emissions as a roundtrip flight between London and New York generates (5).
With much of the maths around carbon emissions, numbers vary widely, so stating a definitive statistic is tricky. Regardless of exact numbers, it seems that the only tangible mitigating effect we can have - short of simply not owning a smartphone or barely using it - is to buy fewer devices and keep using them for longer.
As with mobile phones, much of the emissions from computers comes from the production of these devices. In fact, one estimate claims that about 75-85% of their total carbon footprint is generated before the computer is even shipped out (6) - this includes mining for the materials used in its construction and the energy used during manufacturing.
But beyond production and shipping, what is the energy consumption of a typical computer, and how can individuals lower this? Interestingly, this is a case of ‘little things that matter’, as explained on the Microsoft Sustainable Software blog:
"The biggest contributor to embodied carbon comes from the integrated circuits within the system especially as our devices get smaller and more powerful. These include components such as CPUs, graphics processing units or GPUs, solid-state drives or SSDs, memory, network processors, wireless processors, voltage regulators, and many more." (7)
This means that small changes to the way your computer runs those components could result in greater efficiencies and lower carbon emissions over time. If you want to dig a little deeper, we ran a little experiment using one of our colleagues’ home office set-up.
Despite the fact that all computers use integrated circuits, studies have shown that desktop computers use more energy and cause higher emissions when in use than laptops, in fact up to around 175 kg of CO2 a year (8). Compare that to a laptop’s emissions, which, depending on use, lie between 40-90 kg of CO2 in a year. As Henry’s small scale experiment shows, many variables impact on power consumption - from hardware used to processes run, and hours spent actively working on the computer as well as whether or not a user turns the device off when not in use. Hardware also includes external devices like additional screens, modems, printers, cameras and microphones (9), all of which come with their own CO2 footprint, much of it, again, generated pre-sale.
If you wanted to cut down on emissions, a good place to start would be to
This one is a doozy. Entire white papers have been written about the carbon emissions of servers and data centres, and we will not attempt to compete with them here. In short, every time we conduct a search online, watch a video or run any application we consume power. So far so obvious. But why and what is the carbon footprint of these daily actions? We will look at the basics.
All apps and software need to be run on servers from which individuals can access them on their own devices. These servers are generally housed in large-scale data centres. In 2021 there were about 8,000 data centres globally, responsible for about 1% of the world’s total energy consumption (10). If you are interested, Stackscale has a fascinating map of the global network of servers and submarine cables (11).
Global energy consumption by all servers is a bit of a guessing game, but most sources agree that the total equals that of entire countries. In fact, one estimate states that if all servers worldwide were a country, its energy consumption would rank it 11th in the world (12).
Google’s server network was estimated to comprise over 2.5 million servers in 2016 (13). And while no public data exists on their energy consumption, a 2020 report states that Google used 15.5 terawatt hours of electricity across all their operations, with the majority of that going to their data centres (14). Fellow tech behemoths Facebook and Amazon also run huge networks of centres with equally high energy consumption.
The bulk of electricity in these data centres is used for cooling and running the servers. This makes sense if you consider the heat generated even by your puny laptop - then multiply that by several thousand. In many cases, measurements show that there is actually higher energy consumption in the infrastructure set up to store and maintain servers, than there is being consumed by the servers themselves (15).
As with much of the debate around emissions and climate change, individual actions can seem negligible and obsolete. But at Lola Tech we are big believers in the power of individuals - so here are a few things you can do:
We sourced most of this information from various online publications and websites, which you can see listed below. But one particular source stood out as being a treasure trove of data, and that is Make Berners-Lee’s book ‘How Bad Are Bananas - the carbon footprint of everything’. We highly recommend you get yourself a copy (used, ideally! And maybe not via Amazon…).
(1)- (3) Lee, P., Boucaille, A., Calugar-Pop, C. and Raviprakash, S. (2022) “Making smartphones sustainable: Live long and greener”, Deloitte Insights Magazine (30) [online]; Available at: https://www2.deloitte.com/us/en/insights/industry/technology/technology-media-and-telecom-predictions/2022/environmental-impact-smartphones.html [Accessed 19 July 2022]
(4) Honest Mobile (2020) “What’s the carbon footprint of my smartphone?”, honestmobile.co.uk, August 25, 2020; Available at: https://honestmobile.co.uk/2020/08/25/whats-the-carbon-footprint-of-my-smartphone [Accessed 19 July, 2022]
(5) Viessmann (2019) “The carbon footprint of (nearly) everything”; www.viessmann.co.uk, Available at: https://www.viessmann.co.uk/company/blog/the-carbon-footprint-of-nearly-everything [Accessed 19 July, 2022]
(6) Circular Computing (2021) “What is the carbon footprint of a laptop?”, www.circularcomputing.com, 9 August 2021; Available at: https://circularcomputing.com/news/carbon-footprint-laptop/ [Accessed 20 July 2022]
(7) Manne, S. (2020) “Examining the carbon footprint of devices”, Microsoft Sustainable Software blog, 23 November 2020; Available at https://devblogs.microsoft.com/sustainable-software/examining-the-carbon-footprint-of-devices/ [Accessed at 21 July 2022]
(8) Energuide, “How much power does a computer use? And how much CO2 does that represent?”; www.energuide.be; Available at: https://www.energuide.be/en/questions-answers/how-much-power-does-a-computer-use-and-how-much-co2-does-that-represent/54/ [Accessed 20 July 2022]
(9) Zetterlund T. (2022) “Do you know how much CO2 your computer use?” (sic), Torbjorn Zetterlund, 4 January 2022; Available at: https://torbjornzetterlund.com/do-you-know-how-much-co2-your-computer-use/ [Accessed 20 July 2022]
(10) Daigle, B. (2021) "Data centers around the world: A quick look", United States International Trade Commission, Executive Briefings on Trade (May 2021); Available at: https://www.usitc.gov/publications/332/executive_briefings/ebot_data_centers_around_the_world.pdf [Accessed 20 July 2022]
(11) Stackscale (2022) “All internet servers together draw the world map” Stackscale Blog, 21 March 2022; AVailable at: https://www.stackscale.com/blog/internet-servers-map/ [Accessed 19 July, 2022]
(12) Zodhya (2022) "How much power do the servers consume?" (sic) Medium, 19 March 2022; Available at: https://medium.com/@zodhyatech/how-much-power-do-the-servers-consume-8f9620be71a [Accessed 20 July 2022]
(13) DataCentre Knowledge (2017) "Google data center FAQ" DataCenter Knowledge, 17 March 2017; Available at: https://www.datacenterknowledge.com/archives/2017/03/16/google-data-center-faq [Accessed 19 July 2022]
(14) Google (2021) "Environmental Report", December 2021; Available at: https://www.gstatic.com/gumdrop/sustainability/google-2021-environmental-report.pdf [Accessed 15 August 2022]
(15) Booth, J. (2020) "UK data centres - carbon neutral by 2030?" UK Energy Research Centre, 10 September 2020; Available at: https://ukerc.ac.uk/news/uk-data-centres-carbon-neutral-by-2030 [Accessed 20 July 2022]
(16) Mould, R., "Sustainable web design – how to reduce your website’s carbon footprint?", RJM Digital blog; Available at: https://www.rjm.digital/blog/website-design-and-development/sustainable-web-design [Accessed 19 July 2022]
