If you’re concerned about the carbon emissions of your website, give yourself a good old pat on the back! The environmental impact of our work can reach far and wide, and asking the question “what are the carbon emissions of a website” is a highly valid one. Read on to find out why.

During the first lockdown of 2020, we made time to form our own climate strategy after one of our climate-conscious clients asked us: “How do we offset the carbon footprint of our website?”

Being an outdoorsy and nature-loving team, we’ve always been extremely passionate about doing our bit for the planet. Sure, we power our devices, homes and workspaces with green energy, but does that make us 100% sustainable?

What are the carbon emissions of a website?

During our research into this we came across some powerful statistics, this one being the most jaw-dropping:

The majority of websites are hosted on commercial web servers which exist in large data centres, like the one in the picture below. Data centres are big buildings packed full with racks and racks of large servers that never get switched off, because of course if servers get switched off, websites go down. These servers not only need constant power, they need a lot of cooling too, as well as lots of lighting so that technicians can see what they’re doing when they work on them.

The carbon emissions of a website will vary, based on these main factors:

• How well the website’s code is written; bloated code means more energy will be required to load the web pages and therefore the emissions will be higher.
• How energy-efficient the data centre is that hosts the website: if cooling systems and lighting dynamically shut off when not needed, then this will lower the carbon emissions of the data centre.
• What kind of energy is used to power the data centre: is it green, renewable energy? If it isn’t, then the emissions will need to be offset through carbon offsetting initiatives.
• Finally, the energy sources used to power the devices of the people who are actually using the website. This one is interesting because it could easily be overlooked, yet we feel it’s still a significant part of the equation.

Ooooh! Big fancy images – but are they compressed?

Images are a massive contributor to web page load speed and some might say the Holy Grail for fast loading websites is proper compression of images. If images are automatically compressed by the website’s code when they are uploaded, enormous savings can be made on the amount of data transferred for each page view. A compressed image could be less than 500kb in size, whereas uncompressed images will stay the same size as the original file. With digital cameras and smartphones producing images of 5mb, 10mb, even in excess of 30mb in some cases, this is why image compression is such a big deal.

The people over at Website Carbon say that 1.8kWh of energy is used per 1 GB of data transferred. But what does that mean in practical terms? Here’s our clever interpretation of those numbers, with acknowledgement that not all websites are created equal; slow loading websites will clearly use more energy than fast loading ones…:

Carbon emissions of energy-efficient websites

1 page view = 1 gram CO2

Carbon emissions of websites that are not energy efficient

1 page view = up to 6 grams CO2

Website carbon emissions linked to website traffic

It is logical that website carbon emissions increase as website traffic increases; the more data being transmitted, the more energy will be consumed. If you use tracking tools such as Google Analytics you can get an idea of how many visitors your site has received (excluding those who have disabled cookies of course). It’s then a case of understanding much as you can about how efficient the website is and then multiplying page views by between 1 and 6 grams of CO2.

On our own servers, the average site we look after receives around 10,000 page views per month.

If you have a helpful web host, they’ll probably be able to give you a more accurate reading of how many visitors your website has. The reason for this is that it is possible to monitor traffic levels at server level, and this data includes all traffic, not just those who have accepted cookies. So we would encourage anyone who’s really serious about finding this information out to speak to their web host about web traffic at server level, and compare it to the data in their Google Analytics account, because the more web users find out about cookies, the less likely they are to accept them!

Our climate positive approach

At Winter Design, we have made it a core component of our managed WordPress hosting to offer two green initiatives:

1. we host all client sites on servers that are powered by 100% renewable energy
2. for good measure, we commit to a carbon offsetting programme to offset the emissions of the inbound traffic to the websites we host.

Are you interested in learning more about your website’s carbon footprint? Get in touch with us to find out more.