The web (and your website) relies on a vast network of computers to move data around the Internet. This data can be an email, a photo or the latest episode of your favourite TV show. But, how much energy does moving this data use, and what is the cost to the environment?

We all know that the technology we use has a direct impact on the environment and the amount of CO2 produced. We also know that some of the top advice to help reduce CO2 levels is to turn off appliances when we aren’t using them. However, while you’re browsing the web or streaming your favourite TV show, there are lots of other computers at work which you can’t turn off or control.

How much energy does the web use?

It is difficult to precisely measure the impact of web browsing on the environment. This is mainly due to the amount of shared Internet infrastructure. However, we can make some estimates based upon existing information.

Research conducted in 2017 estimated that 0.01kWh of electricity would be needed to transfer 1GB of data by 2020 (excluding data centres and home routers/computers) and in 2019 it was calculated that 0.256kg of COis produced per kWh of electricity. Based on these numbers we can calculate that transferring 1GB of data would produce 2.56g of CO2.

In 2019, the average broadband connection used 315GB of data every month, this is an increase of 31% from the previous year. This means that in 2019, a typical broadband user would produce almost 1kg of CO2 per month. That is the same as driving 2.5 miles in a car.

How can we save energy on the web?

Trying to reduce the amount of CO2 produced by using the web is difficult, since you only control one small part. But there are some changes which are already happening, plus some extra things you can do to help ensure your impact is minimised.

Data centres are becoming more efficient

The number of data centres around the world has increased rapidly to meet the demand for their services. However, despite the increase in numbers, boosted efficiency means data centres still only account for around 1% of global energy use. Also, a number of data centres are powered entirely by renewable energy so their environmental impact is minimised even further.

Download music and videos instead of streaming

Streaming services are convenient, however streaming music or video means you are transferring the data every time you enjoy them. Downloading means that data only gets transferred once. The difference between this could be significant when you consider Netflix uses 3GB of data per hour of HD video.

Use a tablet when browsing the web

Tablets are more power efficient than laptops and desktops. A typical laptop uses between 20 and 60 watts of power while a tablet uses 15 watts of power. If you use a tablet instead of a laptop to browse the web this could use significantly less energy.

Optimise your website

If you run your own website, you can ensure that the images, CSS and JavaScript it uses are optimised and compressed to reduce the amount of data transferred. This also has the benefit of ensuring that your website loads quickly and doesn’t keep the user waiting. We can help you with this process as part of our web development service. 


The contribution of individual websites to overall CO2 emissions are small. However, helping to ensure that they use as little data as possible means less energy will be consumed. When this is combined with increasingly efficient computer hardware; it contributes to even greater energy savings.