
Summary
Many websites are not optimised for website performance to minimise page size. In almost every case, a more data-efficient website provides a faster, smoother experience for visitors with a smaller carbon footprint per page.
So, there’s a very high chance your WordPress website’s carbon footprint and sustainability is not as good as it could (or should) be. Read our recommendations on how to improve your WordPress website’s speed.
In fact, at WordCamp Europe this summer, sustainability was a key topic across the whole three-day conference.
What you’ll learn
- Summary
- How is website performance linked to sustainability?
- Start by measuring your website’s performance
- Understanding website page weight
- Optimising your WordPress website with a performance plugin
- The advantages of a more sustainable website
- A sustainable WordPress website will outperform others
- Why not start by measuring your website’s carbon footprint?
- Read more articles
How is website performance linked to sustainability?
Many people don’t realise their website has a carbon footprint because they’re not physical objects. This is understandable – you don’t see the pollution coming from your computer or mobile phone!

The average small site produces around 60kg of carbon every year, which is equivalent to an average car driving 270 miles.
The carbon emissions are created by:
- The electricity used by the data centre where your website is hosted – servers, systems, electricity, and cooling mechanisms
- The data transfer network from your hosting server to your site visitor’s device
- The devices used to view your website online.
- The embodied carbon in the manufacturing of the equipment and chips used at the data centre, transmission network, and device.
So the lower the amount of data required, the faster your page will be presented to your visitors. And that’s why measuring your website performance is important.
Start by measuring your website’s performance
So, what is website performance really? Essentially, it comes down to speed**.
How fast your pages load, which is known as page speed, and how fast your site responds to users’ actions, such as scrolling and clicks, within their browsers.
And what determines your site’s speed? A lot of that is down to data.
Many websites are not optimised to reduce data. What that means is when each page loads, there is a lot of data to download from the hosting server and transmit to the device. And every single time a visitor requests a page to visit, all that data makes the page slow to load.
As a quick test, open your browser in ‘private mode’ and test your homepage using Google’s page speed test tool.

If you want more detail, then Gtmetrix has a free tool which tells you which parts of a page have the most data.

** It’s important to note that other factors, such as ease-of-use and accessibility, influence website performance.
Understanding website page weight
Page weight is the number of bytes of data transferred from your server to a user’s device for the page to load in their browser.
Web pages with a larger page weight will be inefficient, as they require more electricity to send the data and take longer to present the page to the user.
A range of factors influence your page weight and, as a result, your site’s performance, including:
- Your WordPress theme and the amount of unnecessary code it includes
- Your use of WordPress plugins, including page builders and adding additional features such as ecommerce and event management
- Your background colours, fonts, and design elements
- The number and size of photos, videos, and media files
- Documents such as PDF files to be downloaded on pages
- Scripts, tracking code, third-party APIs and anything else that adds to the total data of your web pages.
Optimising your WordPress website with a performance plugin
A proven way to improve your site’s performance is to reduce your page weight as much as possible. A performance plugin intervenes in your WordPress site processes as pages load to make them faster and reduce the data transferred. These plugins most commonly optimise your cache, files, images, or database.
If you are creating a new website, then make sure you ask your designers and developers to build performance and optimisation from the start.
If you have an existing website there are some popular WordPress performance plugins which can resolve common issues.
Popular WordPress website performance plugins
Perfmatters
Is one of our favourite performance plugins. It is great at removing unused CSS, delaying JavaScript, optimising the fonts on your site and lazy-loading images. It also has an advanced asset optimisation feature.
Nitropack
Has many features you need to improve your WordPress website speed, including a CDN, lazy loading, image optimization, and CSS and JavaScript modification. However, this plugin can be expensive depending on the amount of traffic your site gets.
WP Rocket
Is a good alternative to Nitropack and includes advanced caching, image lazy loading, database cleanup, and file optimisation.
Autoptimize
Fills in the gaps left by WP Rocket. This plugin is good if you need to minify CSS, optimise JavaScript, and even cleanup HTML.
WP-Optimize
Is one of the best free WordPress plugins to improve your WordPress website performance, with advanced caching rules, database cleanup and image optimisation included.
Asset Cleanup
All WordPress plugins create assets, unfortunately, some plugins load their assets on every page even if they’re not being used. This plugin cleans up these assets so they are only loaded when required for a page.
Just be careful to test first!
It is worth testing your chosen plugin on a copy (development or staging version of your site) before adding it to your live site.
Some performance plugins have settings that can break the styling and change how your website works.
The advantages of a more sustainable website
The more energy-efficient your website is, the better it will perform, providing the fastest possible user experience for your visitors.
Quick test – When was the last time you tested your website for its loading times and page speed? Let us know, and we’ll tell you how you compare to the top performers in your industry.
This influences your visitor retention, bounce rates, and conversion rates, which all impact the amount of revenue your site can generate for your business.

Walmart discovered that improving page load time by one second increased conversions by 2%
So, focusing on sustainability is an easy – but highly valuable – way to improve your overall marketing results:
- Accelerating page speed
- Increasing conversions
- Delivering an improved user experience
- Reducing bounce rates
- Increasing visitor retention
- Higher SEO rankings
A sustainable WordPress website will outperform others
There’s a link between your website’s carbon footprint and its speed and performance. But many marketers we’ve spoken to over the past year don’t even realise their website has a carbon footprint at all.
When users’ tolerance for frustrating, slow websites is at an all-time low, optimising your website is vital for marketing success. Large page weights and slow page speeds cause poor energy efficiency.
You can find a simple but detailed guide to optimising your WordPress website and reducing its carbon footprint here.
Why not start by measuring your website’s carbon footprint?
Before you improve your website’s performance, start by measuring the carbon footprint – then you can report on the carbon footprint savings as you speed up your site.
Use our Kanoppi carbon footprint plugin. This intuitive tool provides measurements and insights about your WordPress website’s carbon footprint and helpful recommendations for reducing it.
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