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Measuring the climate impact of our digital services at GDS

Graphic saying 'GDS CO2 per year is equivalent to 770 cars or 400 homes'

Earlier this year, GDS formed a Sustainability Network to help our department reduce greenhouse gas emissions. 

We were inspired by the government’s commitment this year to reduce emissions to “net zero” by 2050, and the government’s Sustainable Technology Strategy 2020.

We decided to measure how much CO2 is produced as a result of our work, so we started with the largest potential source – our digital services.

Why we chose to focus on our digital services

When we think about reducing emissions, we often think of flying less or switching the lights off. We don’t tend to think about the energy it takes to keep digital services like GOV.UK up and running. But at GDS, this is actually our biggest potential source of emissions.

The IT industry actually uses 3.6% of the world’s electricity, and it produces 1.4% of the overall greenhouse gas emissions.

Websites like GOV.UK stay up and running thanks to thousands of computers in data centres. These computers are powered by electricity, which is a potential source of CO2, depending on how it’s produced.

At GDS, we use data centres from various companies, including Amazon Web Services (AWS). We decided to find out how our data centres source their electricity, and how much CO2 they produce through keeping services like GOV.UK, GOV.UK Verify and GOV.UK Notify running.

What we wanted to find out

To estimate the climate impact of our digital services, we wanted to find out a couple of key things:

  1. How much electricity does it take to power our digital services?
  2. How much CO2 is produced by that electricity? This would depend on how much of the electricity is generated from ‘green’ energy like solar or wind, and how much comes from burning fossil fuels.

To tackle these 2 questions, we asked our hosting providers for data on our electricity usage and CO2 emissions. We also made a rough estimate of our overall electricity usage. And, we estimated the amount of CO2 emissions produced by our electricity, using data from this electricity map produced by a company called Tomorrow.

Problems getting the data

We asked our hosting providers, Amazon Web Services, UKCloud and Carrenza, to tell us how much electricity we use, and how much CO2 we produce.

Only one of our providers, UKCloud, agreed to give us data about our electricity usage. For Amazon and Carrenza, we made a guess about the amount of electricity we use, assuming a percentage of our monthly bill.

In addition, neither Amazon nor Google currently shares information about how much CO2 their data centres produce. Although they claim that some of their data centres are “carbon neutral” or “100% renewable”, they do not explain to what extent they achieve this through offsetting – for example, through renewable energy projects elsewhere. Offsetting is useful, but it’s more important to avoid emitting CO2 in the first place.

We want to host our services in the most sustainable way we can. So we need to know how much CO2 is actually produced per kilowatt of electricity, per data centre.

Hopefully, our hosting providers will provide this data soon, now that Amazon has announced new commitments to measure and reduce emissions.

How much CO2 do GDS digital services produce?

Because our hosting providers didn’t share our electricity usage data with us, we went ahead and estimated it, based on the information we did have, including our recent bills. 

We estimated that the maximum amount of CO2 we produce is around 4,000 tonnes of CO2 per year. That’s the equivalent of the CO2 produced by the energy used by a village of 400 homes every year. Or the fuel burned by 770 cars, on average, in a year.

This is almost certainly GDS’s largest source of emissions. So we are keen to find ways to bring it down to zero, in order to meet our commitments.

What’s next

It’s encouraging to see the largest hosting providers, Amazon and Google, make announcements about measuring and reducing their CO2 emissions. If our providers make their data centres more sustainable, this will reduce our emissions. It will also benefit all their customers, including other teams in government.

Over the next year, we’d like to work with colleagues across government to:

  1. Reduce the electricity we need to run our services – for example, by making our digital services more efficient
  2. Keep asking our providers for better data to help us develop guidance on the most sustainable data centres by region and country 
  3. Update the Service Manual’s guidance – 'Deciding how to host your service' – based on what we learn

Let us know in the comments below if you’d like to work together to reduce the climate impact of government services.

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  1. Comment by Chowdhury Tarul Ahsan posted on

    I'm glad that the government is taking measures for eco friendly hosting. Though it will take time to completely build the awareness but at least the step is taken.

  2. Comment by Adam Turner posted on

    Hi. This is great. Today we published the annual report against the Sustainable Technology Strategy mentioned in your introduction
    Please speak to me, or any member of the HMG STAR community for how we did it. Your figures were included under the Cabinet Office return.
    We'd love to assist you with your work.
    Our new strategy will be released next year and we will be publishing policy for cloud procurement, ethical and social impacts and energy efficiency to deliver our sustainability outcomes.

  3. Comment by Nicky Stewart posted on

    Hi we are very happy to support this great work and will provide any data we can to help. Polite request - could our name be amended to UKCloud, rather than UK Cloud? thanks in advance

    • Replies to Nicky Stewart>

      Comment by Emily Labram posted on

      Hi Nicky,

      Thanks for your support - much appreciated!

      My apologies for the mistake - we've corrected the name.

      Best wishes,

  4. Comment by Ben Rusholme posted on

    This is an important topic so I read this with interest. I am pleased you have made a start by estimating the carbon impact of your digital services. I look forward to hearing more about this work, particularly increasing efficiency and use of renewable energy.

  5. Comment by Colin posted on

    This is a good start, however any digital service requires labour required to build, run and maintain the service. I would suggest the next step should be to assess the labour involved and how much CO2 this generates (IT equipment, travel, buildings, etc).

    • Replies to Colin>

      Comment by Emily Labram posted on

      Hi Colin,

      You're absolutely right.

      We started with data centres as they were probably the largest source of emissions. But to calculate a digital service's total emissions, we will need to measure the other sources you mention.

      We know that other departments have done good work on measuring the emissions caused by government office buildings, for example. We'd be keen to hear more, and share what we learn, too.

      Best wishes,

  6. Comment by Neil Ranade posted on

    I am just putting together an email campaign to encourage more people to register for paperless billing for council tax and am using the emissions data as a tactic to change behaviour.

    Currently I have calculated - albeit, approximately that to send 1 council tax bill results in 439 gms of CO2 being released into the atmosphere. This includes paper production, printing costs, transport (road and rail) and factory office energy costs.

    Scaling this up to say 50,000 households equates to 22 metric tonnes or the equivalent of 5 cars not being driven for a whole year.

    CO2 emissions for 1 email equate to approx 4gms.

    • Replies to Neil Ranade>

      Comment by Emily Labram posted on

      Hi Neil,

      This is absolutely great work!

      We're excited to hear how you've used the same approach to encourage and reward your users for reducing CO2.

      How did the campaign go? We'd be interested to know if you've seen any change in the rate of paperless billing.

      Thanks and best wishes,

  7. Comment by Ravi posted on

    This is genuinely good work - really well done on trying to shine a light on a fairly hidden source of emissions.

    When I read the blog, it reminded me of this article ( which said that, 10 years ago at least, two Google searches were as carbon emitting as boiling a kettle - a pretty catchy comparison!

    I wonder if such comparisons might be useful in changing people's behaviours to more environmentally responsible usage of digital services?

    • Replies to Ravi>

      Comment by Emily Labram posted on

      Hi Ravi,

      Thanks for the feedback! Yes, we tried to make the emissions easier to understand by using comparisons to everyday things like heating, flying, driving.

      I like your idea of giving positive feedback to encourage change. E.g. when developers figure out how to shut down the resources they don't need overnight, we could say "you've saved as much CO2 per day as three cars" or "boiling a kettle 10 times per day".

      Employers could also look at introducing benefits to all staff for their individual efforts, e.g. through schemes like Climate Perks, which gives free holiday days to staff who use trains instead of flying on holiday:

      Good stuff!

  8. Comment by Egle posted on

    Super interesting article! I'd love to help on a personal basis and wonder what would be the steps or if possible at all!

    • Replies to Egle>

      Comment by Emily Labram posted on

      Hi Egle,

      Thanks very much!

      There are so many possibilities for getting involved, either within a department, across government or in the wider industry. It's definitely a case of what interests you the most.

      A few pointers:

      OneTeamGov are a great cross-government community who are running an unconference on climate action in January. You can find them on Twitter.

      "Climate Action Tech" have a Slack community for people in tech which is full of interesting projects and opportunities.

      And the Green Web Foundation have lots more guidance and expertise on measuring and reducing CO2 emissions from digital services.

      Or you can reach me on Twitter and we can discuss more!

      Best wishes,

  9. Comment by david posted on

    Have you considered the environmental benefits of your digital services (e.g. how many paper forms have been replaced)?

    • Replies to david>

      Comment by Emily Labram posted on

      Hi David,

      This is a good point, thanks for flagging.

      It would be great to understand how much CO2 we save through digitising a service, when compared to paper, phone calls or in-person services.

      We would love to make this kind of comparison in future in order to understand the benefits of digital from an environmental perspective.

      At the same time, we are also aware of the need to reduce *all* emissions in order to meet our legal commitments. That was the prompt for this work, and since GDS only runs digital services, it was our starting point.

      If you see any data on the comparison between digital and non-digital services, in terms of CO2 emissions, do let us know!


  10. Comment by Adam posted on

    This is really interesting and so important to understand our footprint in the sector - it can be easily forgotten that these services actually have to be powered somehow!

    It'd be great as a future step to understand our impact of more traditional assets, such as heating and lighting in government buildings. Ie. how much of the civil service energy use is through green energy suppliers?

    Would be great to get involved!

    • Replies to Adam>

      Comment by Emily Labram posted on

      Hi Adam, absolutely!

      We are actually doing a project this week at GDS to measure the rest of our CO2 footprint. That will include the heating and lighting of our building, as you mention.

      I imagine other departments have done this already. Would be great to share more about the process!

      There are lots of ways to get involved in this work either within our own departments or by getting involved in the wider tech industry. I recommend the Slack community "Climate Action Tech" for inspiration. They are also organising an unconference on 18 October called "OMG Climate" in London which may be of interest too.

      Best wishes,