Sustainable IT

The use of IT equipment is rising exponentially. We are using more equipment all the time. How many of us have multiple devices such as a laptop, mobile phone, smart speaker, smart watch, games console – the list goes on. All these devices have a carbon footprint, both in their manufacture and in use - even data has a carbon cost. ICT (Information and communications technology) accounts for around 2.5% of global emissions. This article looks at some of the things you can do to make a difference.

Note the figures below are all from Mike Berners-Lee book ‘How bad are bananas? The carbon footprint of everything’. They are CO2e - Carbon dioxide equivalent, meaning CO2 and other greenhouse gases, and are all ‘best estimates’. To put them in perspective, in the UK we currently each have an annual carbon footprint of around 12.7 tonnes CO2e per year. This needs to be a lot lower - Mike Berner-Lee suggests a 5-tonne lifestyle should be a target in the next few years - so we all need to make some changes.

Use less

At work

The University is aiming to support one device per person.

screen iconMany people need a second screen to be able to work effectively, but if you don’t then sticking to one screen will reduce your electricity consumption.

power button iconSwitch off your computer and monitor (and other devices) when you aren't using them. Even if your computer needs to be on, remember to switch off your monitor (if you have a separate one) if it isn't needed.

computer iconThe standard warranty period for University laptops is five years, no need to replace it after just three. When you do need to replace your University device, make sure it is disposed of in accordance with University procedures – you'll find the guidance listed under 'Computers'.

Electonrics watchDid you know the University is a founder member of Electronics Watch - an independent monitoring organisation that helps organisations work together and collaborate with their supply chain partners to protect the rights of workers in production regions? The University use Electronics Watch's monitoring services to achieve compliance with labour rights safety standards in the supply chains of the ICT hardware goods we purchase. The University also has a sustainable procurement standard, available on the Environmental Management System.

leaf iconDo you need to print? If you do, print double-sided to reduce the amount of paper you use. You can find out the environmental impact of any printing done through MyPrint by logging on to and clicking on ‘Environmental Impact’. All the standard paper used in MyPrint printers is 100% recycled, and used paper and toner can be recycled. 

At home

If you are thinking of buying a new device, stop and think – do you really need it? IT equipment not only generates emissions, but also has other impacts on the environment such as toxic waste if it isn’t disposed of properly.

For existing devices such as laptops or smartphones, using them longer is usually the best policy. If you are looking for a new TV or monitor, size matters – unsurprisingly huge screens are worse than smaller ones, even though they have become more efficient. LED screens are much more efficient than plasma screens, and if you still have an old CRT (cathode ray tube) TV you’ll probably break even on the carbon cost of manufacturing in about 5 years (if you watch an average amount of TV).

What about data?

When you send an email, its footprint depends partly on the electricity used by all the equipment needed to send it, including network and data centre devices. Example costs:  

But the biggest proportion of this is in the manufacture of the devices – 84% for a smart phone. And of course, if you are reading emails at work, your laptop or computer is already on and using electricity.

We all suffer from information overload, so sending fewer emails is a good idea, but it won’t have much effect on your carbon footprint.  

Video calls

The carbon footprint of Zoom / Teams calls is largely dependent on the device you are using:

Plus the embodied emissions in the device you are using. As with emails, the bulk of emissions are embodied in the device itself and the actual additional emissions from the call are fairly minimal.

Of course, the big saving from video calls is the lack of commuting – four of you driving 5 miles each could net 16kg of emissions!

WiFi or Mobile data?

3G network consumes more energy than 4G and, WiFi uses the least. So while you are at home, use WiFi rather than a mobile network. On campus you can use eduroam WiFi - it not only works on campus at Leeds, but at most universities and teaching hospitals in the UK and beyond.

Where is the data stored?

It’s estimated that data centres, such as those run by Google, Microsoft and Amazon use about 1 percent of global electricity. But they are much more efficient than they were 10 years ago and these large remote data centres use much less electricity than local storage. As part of the Digital Enablement programme we are moving more services into the cloud, not only as they are more efficient, but also to improve reliability, flexibility and responsiveness.

But remember, the more data we store, the bigger those data centres need to be and deleting data you no longer need is good practice.  

Just Google it?

Searching doesn’t have a big impact on our carbon footprint, around 0.5g CO2e for one simple search on a Smartphone (including the costs embodied in the smartphone, the electricity and Google’s contribution). drawing of the earth as a globe with the words "UoL on ecosia" around it

In the computer clusters on campus the default search engine is Ecosia. They have their own solar plants to power their data centres and plant trees every time someone searches (about 1 tree for every 50 searches). At the time of writing (November 2021), they’ve planted over 137,000,000 trees! Why not make Ecosia your default search engine?

What else can I do?

To find out more about sustainability at the University, visit the Sustainability website and take the ‘Sustainability in Practice’ module (suitable for all University staff). To access the module, log on to Minerva and click on ‘Organisations’.


(with thanks to Jyoti Mishra from Leeds University Business School)