Every time someone visits a website, energy is consumed at three stages:

• Data centres (where your site is hosted)
• Transmission networks (the infrastructure that moves data)
• End-user devices (the laptop, phone, or tablet displaying your content)

The Website Carbon Calculator estimates emissions based on page weight, hosting, and traffic, providing a useful benchmark for measuring your site’s footprint.

To put this in perspective, the average internet user generates approximately 400g of CO2 per year just from browsing. A single web search emits around 0.8g of CO2. Stream for just 60 minutes and you’ve released approximately 36g of CO2. These seem small in isolation, but scale them across billions of users and the numbers become staggering.

The good news is that website owners can significantly reduce these emissions through thoughtful design and development choices. The difference between a bloated, inefficient site and a lean, optimised one can be an order of magnitude in energy consumption, and that gap directly translates to carbon emissions.

Dark mode has been widely promoted as an energy-saving feature, particularly on devices with OLED screens where black pixels consume no power. But the reality is more nuanced than the marketing suggests.

When dark mode saves energy (and how much)

On OLED and AMOLED displays, dark mode’s effectiveness depends heavily on screen brightness. A study from Purdue University found that at 100% brightness, switching to dark mode saves 39-47% battery power. However, at typical indoor brightness levels (30-50%), savings drop to just 3-9%, a difference most users wouldn’t notice.

The key insight is that brightness level has an exponential effect on power draw. Lowering brightness from 100% to 50% reduces OLED power consumption by approximately 10x, regardless of whether dark mode is enabled. At low brightness, the potential savings from dark mode become marginal because baseline power draw is already low.

Dark mode doesn’t help on LCD screens

LCD displays, still common in laptops and budget devices, use a constant backlight regardless of pixel colour. Dark mode provides no energy benefit on these screens. The backlight remains on whether the screen displays black or white, so colour choice is irrelevant to power consumption.

The practical takeaway for web developers

Offering dark mode is worthwhile for user preference and accessibility (particularly for users with dyslexia), but don’t market it as a major sustainability feature unless you can demonstrate actual energy savings through testing. True black (#000000) backgrounds on OLED devices do save energy, but only when users are at high brightness levels, relatively uncommon during typical indoor use.

Choosing a hosting provider powered by renewable energy is one of the most direct ways to reduce your website’s carbon footprint. But not all “green hosting” claims are created equal, and it’s worth understanding what you’re actually paying for.

What “green hosting” means

Most green hosting providers achieve carbon neutrality through one of three approaches:

• Renewable Energy Certificates (RECs): The host purchases certificates equivalent to their energy consumption, funding renewable projects elsewhere
• Power Purchase Agreements (PPAs): Direct contracts with renewable energy suppliers, ensuring the grid receives renewable energy equivalent to the host’s usage
• On-site renewable generation: Data centres powered by their own solar or wind installations (rare but most direct)

Does green hosting actually reduce emissions?

Yes, but the impact depends on how it’s done. RECs are the least impactful (they’re essentially offsets) while PPAs and direct generation genuinely increase renewable capacity. The Green Web Foundation maintains a database of hosting providers and their sustainability credentials, helping you verify claims and choose genuinely low-carbon hosts.

UK-specific hosting considerations

On roughly a third of days in 2025, at least half of Britain’s electricity came from renewables, so hosting in the UK already starts from a lower carbon baseline than many regions. Choosing a UK-based green host compounds this advantage, particularly if your audience is primarily UK-based (reducing transmission distance as well).

Does Yellow Peach offer green hosting?

At Yellow Peach, we host the majority of our clients’ websites with DigitalOcean, who utilise Equinix data centers running on 100% renewable energy to host infrastructure for its cloud computing services.

WordPress powers 43% of all websites, which means its environmental impact is substantial. But WordPress itself isn’t inherently unsustainable, the issue is how it’s configured and what you build on top of it.

Choose lightweight themes

Bloated themes with dozens of unused features, heavy JavaScript libraries, and complex animations generate unnecessary page weight. That’s exactly why we specialise in custom-built WordPress themes that provide excellent functionality without the environmental overhead.

Audit and remove unused plugins

Every active plugin adds code to your site. Many add front-end scripts that slow load times and increase energy consumption. Regularly audit your plugins and remove anything you’re not actively using. If a plugin does one job well, it’s usually better than a bloated all-in-one solution trying to do everything.

Use performance plugins correctly

Caching, lazy loading, and JavaScript optimisation plugins can significantly reduce energy consumption—but only if configured properly. Misconfigured performance plugins can actually make things worse. Work with someone who understands these tools if you’re not confident in the settings.

Optimise databases regularly

WordPress databases accumulate revisions, spam comments, and orphaned data over time. Regular database optimisation (using plugins like WP-Optimize) reduces the processing required for each page load, lowering server energy consumption.

Building sustainable WordPress sites requires expertise in both performance optimisation and thoughtful architecture. Our WordPress development team specialises in creating lean, efficient sites that perform excellently while minimising environmental impact.

The techniques that reduce environmental impact, lean code, optimised images, fast load times, intuitive UX, thoughtful caching, are the same techniques that create better websites full stop.

Sustainable web development isn’t a separate discipline requiring sacrifices; it’s simply good development practice applied consistently.

The internet’s energy consumption is projected to double by 2030 as AI, streaming, and high-bandwidth applications continue to grow. Individual websites won’t single-handedly solve that problem, but millions of websites making thoughtful decisions collectively can make a measurable difference.

Start with the basics: optimise images, choose green hosting, reduce unnecessary scripts, and design for efficiency. These aren’t radical changes, they’re achievable improvements that benefit your users, your performance metrics, and the planet. And unlike many environmental challenges, this one is entirely within your control.