The carbon footprint of the internet: what’s the environmental impact of being online?

07 February 2022 | OVO Energy

How does scrolling through social media relate to climate change? It might seem abstract, but the internet actually accounts for 10% of global electricity demand. And, as more and more people around the world gain access, that percentage is set to rise to as much as 20% by 20301.

Here’s the lowdown on the carbon footprint of being online, where it comes from, and how to build good digital habits. Plus, find out how we’ve started to decarbonise our online presence here at OVO.

What’s the environmental impact of the internet?

A study by the Boston Consulting Group found that the internet is responsible for around 1 billion tonnes of greenhouse gas emissions per year. That’s about 2% of total emissions. 

In other words, the internet has an impact on the climate that’s roughly comparable to the aviation industry, which is responsible for 2% of CO2 emissions worldwide.

We talk a lot about giving up flying for climate change. So, is it time we started talking about spending less time online, too?

How does the internet create carbon emissions?

It might feel hard to wrap your head around how something like a Google search could emit carbon. After all, we tend to think of the internet as existing in a “cloud”, not part of the physical world. Of course, the truth is a bit more complicated. The carbon footprint of the internet comes from a few different sources.

First of all, there’s the devices you use to actually access the internet. Your laptop, smartphone, TV, and any other connected device has a carbon footprint. That comes both from the manufacturing of your device, and the electricity you use to power it. 

Then there’s the question of all the infrastructure around the world that stores our information and keeps us connected. The many satellites, cables, and data centres that make up the internet (and the electricity used to power them) have a carbon footprint of their own.

The carbon footprint of each individual action we take online is small. But with over half the world’s population (4.9 billion people) being internet users2, the overall effect can be pretty huge. The exact amount of carbon emitted for each click of your mouse will depend on a few different factors, such as the size of the device you’re using, the data centre you’re accessing, and most importantly, where the electricity to power both of them is coming from

Want to learn about some other ways you can fight climate change from home? Here are a few easy ways to reduce your carbon footprint

What’s the environmental impact of an email?

Each email you send racks up an average of 1g of carbon emissions3. That’s about the same weight as a paperclip.

It doesn’t sound like much – until you think about how many emails you actually send and receive. According to our research, Brits send an average of 64 unnecessary emails per day. How many times have you fired off a message just to tell someone “Okay”, or “Thanks!”? 

That’s why we launched our Think Before You Thank campaign, featuring a browser extension and email signature that help you send fewer one-word emails (and explain to people that you’re not doing it to be rude!). Remember, while the carbon footprint of an email is fairly tiny on its own, making daily habit changes like this can be good for our wellbeing, and help us to decarbonise our lives.

What’s the environmental impact of streaming?

Streaming is one of the biggest energy consumers online. In the US, Netflix and YouTube alone represent more than 63% of global internet traffic4.

One study by the University of Bristol in 2016 estimated that the amount of YouTube videos watched that year amounted to over a billion hours, and resulted in 10 million tonnes of carbon dioxide being released into the atmosphere5

When it comes to music, the carbon footprint of streaming a song once is very small. But it’s been shown that if you want to listen to a song more than 27 times, it’s actually greener to buy a physical copy of it rather than streaming.

How about Netflix? Analysis from the International Energy Agency (IEA) suggests that the carbon footprint of streaming is a bit smaller than alarmist media stories have reported in the past. The IEA estimates that an hour of watching something streamed online, such as Netflix, generates about 36g of carbon. That’s relatively little, compared to travelling by bus for an hour (150g of carbon emissions), or driving a car for a mile (710g)6.

So when it comes to the impact we have as individuals, streaming a song or video isn’t the worst thing we can do for the planet. After all, we all need a little light entertainment in our lives sometimes! But when all that streaming is combined, our individual behaviours eventually add up to some pretty big emissions, so it’s important to be aware of the overall impact. 

In the age of convenience and next-day shipping, many of us have been guilty of having items speedily delivered to our door. But what’s the carbon footprint of online shopping? Just like anything else, it depends how often you do it, how much you buy, and what your alternatives would be. 

In general, shopping online is seen as better for the environment than shopping in person. But this is only the case if you’d otherwise be driving to the shops. Importantly, the carbon footprint of your online basket will be bigger if you choose the next-day delivery option – and even more so if you return your items, as 1 in 3 shoppers do7.

To learn more about sustainable shopping, read our guide to fast fashion and how it impacts the environment.

How the internet can help us fight the climate crisis

It’s not all doom and gloom. While we should of course be concerned with how much electricity the internet’s eating up, there are also reasons to be optimistic about the digital revolution.

There have been huge improvements in energy efficiency in recent years. This means that even though we’ve become greedier for data, the electricity use of data centres has not rocketed upwards as you might expect. That’s because the data centres are using electricity more efficiently. Lots of tech giants also invest in renewable energy, including Amazon – which is the largest corporate purchaser of renewables in the world8

The internet can also help us to make greener choices in our everyday life. For example, while the average carbon footprint of an email is 1g, the footprint of sending a letter can go up to 29g9

Plus, connected devices like smart meters and other smart home technology will help us to decarbonise home heating, and make our homes more energy efficient – which will be a huge step forward in our fight against the climate crisis.

8 ways to reduce your carbon footprint online

  1. Shut down your computer when you’re done:we may not be able to control how data centres are powered, but we can make sure that we use electricity efficiently in our homes. It’s always best to make sure devices are switched off when they’re not needed. Make sure you unplug your chargers, too – devices that are plugged in but switched off still use up a small amount of electricity13.
  2. Downsize your gadgets: smaller devices use less power. So try doing things on your phone rather than on a computer as much as possible – and if you can, invest in smaller, more efficient gadgets.
  3. Choose a “conscious” cloud: if you back up your data in a cloud, check whether your provider is using renewable electricity to power their data centres. All of the Big Three providers (Google, Amazon, and Microsoft) have pledged to decarbonise their clouds. Find out how they’re doing here.
  4. Make your searches green: the search engine Ecosia is a green alternative to major search engines – and they use the profits generated from your searches to plant trees around the world!
  5. Think before you thank: every time you send an email, ask yourself: does this need to be an email? One message might not make much difference, but if we all get used to saying less online, we could make an impact on our collective carbon footprint.
  6. Change your autoplay settings: one study by Lancaster University found that many people use YouTube or other streaming services as “background noise”, or even fall asleep to them. So help clean up your online habits by avoiding doing this. In most streaming apps, you can adjust your settings so that they won’t keep automatically playing new content once you’ve fallen asleep, or stopped paying attention. 
  7. Spend more time offline: this one sounds simple, but it’s the biggest step of all. The internet is a necessary part of our lives for many of us – but to combat the impact on our climate, we need to collectively rethink how much time we spend online. Even the smallest changes – like limiting your social media use, or buying something locally rather than online – could make a real difference if we all work together.
  8. Switch to green energy: Get a quote from OVO today and join us on the journey to net zero carbon.

How we’re lowering our own digital carbon footprint

As part of our wider mission to become a net zero business, we’ve started taking steps to decarbonise our website. 

The biggest change so far is to migrate away from our legacy content management system, which was pretty inefficient. Now, we’re using a more modern system, and we’re also making sure we use images that are easier to load on your phone or computer (which not only improves your experience, but also uses less data). 

The impact of these changes has so far been pretty promising. Our homepage used to generate 1.49g of carbon per visit – but now, it’s 0.44g. This website carbon calculator currently estimates that is cleaner than 73% of other web pages. Not a bad start!

We also considered sustainability and renewable energy use when choosing which cloud providers to use to back up our data.

These actions are a good beginning to help minimise the impact of our internet use. But we know there’s always more to do. So we’ll keep working on it – because getting to zero carbon is a journey we’re all on together.

Sources and references



3 Mike Berners-Lee, How Bad are Bananas?: The carbon footprint of everything, Profile Books, 2020



6 Mike Berners-Lee, How Bad are Bananas?: The carbon footprint of everything, Profile Books, 2020