Overview
Nathan Wrigley spoke with Charlotte Bax at WordCamp Europe about making websites more sustainable. Charlotte, who transitioned from sustainable lifestyle blogging to web design under the name Digihobbit, now runs ENNOR Toolbox, a startup that measures CO2 emissions from websites and web apps. She presented practical steps for reducing a site’s environmental impact.
Why web sustainability matters
ICT accounts for a significant share of global energy use, often estimated at about 8–10 percent. If the internet were a country it would be among the largest emitters. Much of that footprint is hidden in data centers, networks, hardware production, cooling, and e-waste, so the consequences are easy to overlook. For designers and developers, small changes can scale into large reductions, especially on high-traffic sites.
Practical actions for web creators
Charlotte highlights several concrete areas to reduce emissions and improve efficiency:
1. Green web hosting
– Pick hosts powered by renewables. The Green Web Foundation provides a database and a site-check tool to verify whether hosting runs on renewable energy. Providers can supply evidence for inclusion, and you should check directly with hosts when listings are incomplete.
– Understand differences between generating your own renewable energy, buying from a green supplier, and purchasing certificates; these options vary in impact and credibility.
2. Architecture and UX
– Design navigation and information architecture so users find what they need with fewer page loads. Reducing page views lowers server processing, bandwidth, and CO2 over time.
– Improve search and structure to avoid unnecessary journeys around the site.
3. Design and content (images, fonts, CSS, video)
– Use images only when they add value. Images are usually far heavier than text.
– Resize and scale images correctly; do not serve huge source files when a smaller size is shown in the browser.
– Use modern image formats like WebP or AVIF to cut file sizes with minimal quality loss, and tune quality settings (for example 80–90 percent) to save bytes.
– Use SVG for icons and logos where appropriate; vectors scale cleanly and can be lightweight when optimized. For WordPress, plugins like Safe SVG can reduce security risks.
– Avoid autoplay background videos. They dramatically increase page weight and often harm UX. Use thumbnails or image placeholders and load video only on user interaction (deferred loading).
– Defer embedded players and third-party scripts (YouTube, Vimeo, tracking) until the user chooses to play or interacts, to avoid loading heavy assets and trackers unnecessarily.
4. Caching and server optimizations
– Implement server-side caching so pages are rendered once and served many times instead of regenerating per request.
– Use browser caching for static assets like CSS, fonts, and scripts so repeat views use less bandwidth.
– Use a CDN when your audience is geographically spread; CDNs cache content at edge locations so data travels less distance. Evaluate CDN use based on audience distribution and traffic patterns, since CDNs also store multiple copies.
5. Visitor management and traffic
– Remember the formula: total emissions = page weight × number of visits. High-traffic sites should prioritize reducing per-page weight and managing bot traffic, which can multiply emissions.
– Control bots and unnecessary requests, and prioritize human users where possible.
6. Grid-aware websites
– Explore adaptive, grid-aware approaches that alter the site experience depending on the visitor’s local energy mix. If the local grid is carbon-heavy, show a minimal version; if it is renewably powered, offer richer features. Implementations may use edge workers or client-side methods. This progressive enhancement is promising for high-traffic sites but remains experimental.
WordPress and broader community work
– Charlotte recommends measuring themes and setups rather than assuming one CMS is greener than another. Test page weight and first-load CO2 as experiments.
– Drupal has a sustainability policy; WordPress previously had a formal sustainability team that was disbanded. At WordCamp Europe contributors informally re-formed a sustainability table during Contributor Day and began organizing to revive official efforts. Charlotte is active in promoting sustainability as a core WordPress value.
Mindset and approach
– Sustainable choices are contextual: consider audience, traffic, and site purpose.
– Small improvements on high-traffic sites scale into significant impact. Think beyond individual features and address architecture, caching, and asset weight.
– Treat sustainability as a journey: inspire people, provide simple tools, and encourage conscious choices rather than forcing one-size-fits-all solutions.
Resources and contact
– Green Web Foundation: hosting database and site-check tool for renewables.
– ENNOR Toolbox: Charlotte’s bulk measurement tool for site emissions.
– Work by Fershad Irani and the Green Web Foundation on grid-aware tooling.
– Charlotte (Digihobbit) is reachable on LinkedIn and Mastodon; include context when you contact her.
Conclusion
Digital choices have measurable environmental consequences, and web teams can act now. By focusing on hosting, architecture, optimized images and video, caching, bot management, and experimental adaptive approaches, designers and developers can reduce a site’s carbon footprint. Small, well-targeted improvements, particularly on high-traffic sites, produce outsized benefits.