The 'Green Hosting' Problem — And Why We Built Something Better

In 2022, a digital agency asked a simple question: is our hosting green? Four years later, the industry still doesn't have a straight answer. But we're getting closer.

A few years ago, Supercool — a UK digital agency — published a refreshingly honest post about their attempt to move their clients to greener hosting. Their conclusion, after weeks of research, was bleak. The complexity of web hosting makes it almost impossible, they said, to be confident that your website is entirely green throughout the supply chain.

They weren't wrong. But the questions they raised stuck with us — because they're exactly the questions we've spent two years engineering EcoPigs to answer.

The problem with a green tick

Most website carbon tools work the same way. They measure page weight, check whether the hosting provider appears in a green database, and produce a score. Green tick or no green tick. Clean or dirty.

Supercool spotted the flaw immediately. A Content Delivery Network caches your site on servers around the world. When a carbon tool checks your site, it hits the nearest CDN edge node — which might be powered by renewables in London — while your actual origin server sits on a coal-heavy grid in Virginia.

The tool sees the CDN. It gives you a green tick. Everyone moves on.

But the data centre doing the real work — storing your database, running your application logic, processing your payments — could be anywhere. And "anywhere" matters enormously when electricity grids vary from around 10 gCO₂/kWh in Sweden to over 800 in South Africa.

A green tick doesn't tell you that.

What "green hosting" actually means

Supercool asked a pointed question: is a hosting provider green if they power their offices with renewables but not their data centres? Or vice versa?

It's a fair question, and the answer depends entirely on who's doing the defining. Some providers call themselves green because they buy carbon offsets. Others because their head office has solar panels. Others because they've signed a pledge to reach net zero by 2040.

None of that tells you what's happening to the electrons powering the rack your website sits on, right now, today.

The Green Web Foundation maintains the most rigorous database of verified green hosts. To be listed, a provider needs documented evidence of renewable energy procurement for their data centre operations — not their offices, not their marketing, not a future commitment. Actual energy supply to actual servers.

That's the standard EcoPigs uses. If the Green Web Foundation hasn't verified it, we don't call it green. And even when they have, we only reduce the data centre portion of emissions by 80% — because no hosting operation is perfectly efficient, and because the network infrastructure and your visitors' devices are on their own grids regardless.

Looking behind the CDN

This was the technical challenge that interested us most. If a site is behind Cloudflare or CloudFront, most carbon tools see the CDN edge and stop looking. EcoPigs finds the origin.

Our hosting detection works in layers. We check the Green Web Foundation, resolve the domain's IP and geolocate it, and if we detect a known CDN — Cloudflare, Akamai, Amazon CloudFront, Fastly, Google Cloud CDN — we flag it and trace back to the origin server. For government and institutional domains, TLD patterns give us high-confidence inference: a .gov.uk site behind Cloudflare almost certainly has its origin in the UK. For commercial sites, we re-resolve without the www prefix and compare IPs.

It's not perfect. We assign confidence scores rather than certainties. But it means we calculate emissions using the grid intensity of where your data actually lives — not where the nearest CDN edge happened to respond.

The grid matters more than the green tick

Here's something that surprised us when we started building EcoPigs: switching hosting location often has a bigger impact than switching to a "green" provider.

France generates most of its electricity from nuclear. Its grid intensity sits around 56 gCO₂ per kilowatt-hour. The US averages 370. Poland, still heavily coal-dependent, sits at 680.

An identical website, serving identical content, produces twelve times more carbon emissions hosted in Poland than in France — green certification aside.

This is why EcoPigs uses a five-tier grid intensity system rather than a single global average — pulling live generation mix data for the UK and EU (updated every 30 minutes), EPA figures for the US, Electricity Maps data covering 80+ countries, and Ember 2024 baselines where live feeds aren't available. When EcoPigs calculates your emissions, it uses the most accurate, most current data available for the specific country your server is in. Not a global average. Not a guess.

Four numbers, not one

The original Sustainable Web Design model — the methodology behind Website Carbon and most other tools — produces a single number: grams of CO₂ per page view. It's simple and useful as a rough guide. But it treats the entire delivery chain as a single black box.

EcoPigs breaks it into four segments: the data centre hosting your site, the network delivering your content, your visitor's device, and the embodied carbon baked into all that hardware. Each segment uses its own energy intensity constant, drawn from IEA 2024 and Malmodin 2023 research.

And critically, green hosting only affects the first one. Your visitor's phone doesn't care whether your server runs on wind power.

This matters because it gives you an honest picture. Green hosting typically reduces total emissions by 25–35%, not the 100% that a simple green tick might imply. That's still significant — but it's one lever among several, not a silver bullet.

What we're honest about

Supercool described a complex supply chain: data centres, web servers, proxy servers, firewalls, payment gateways, caching layers, load balancers. They're right — and we don't claim to audit all of it.

EcoPigs traces the primary delivery path: your domain, any CDN in front of it, and the origin server behind it. We don't audit your Stripe integration's hosting, your analytics provider's data centres, or the CDN powering your font library.

Those are real emissions. But they're largely outside a website owner's control, and attempting to measure them without access to those providers' infrastructure would mean guessing. We'd rather give you an accurate, verifiable number for the infrastructure you can actually influence than an impressive-sounding number built on assumptions you can't interrogate.

From measurement to action

The most telling line in Supercool's post was about advocacy. They found that simply asking their hosting provider about sustainability led, within a month, to a VP of Social Impact being appointed. Customer pressure works.

But advocacy is more effective with data.

An EcoPigs report doesn't just tell you your emissions — it quantifies what switching hosting provider would actually save. It shows the difference between your current grid and a cleaner one. It tells you whether your green hosting certification is moving the needle, or whether your page weight is the bigger problem.

That's the difference between "we care about sustainability" and "our website produces 2.3 tonnes of CO₂ annually, and moving from US hosting to a verified green provider in France would reduce that by 70%."

Where we are now

Four years after Supercool's post, the mysteries of green hosting are less mysterious — but only if you're willing to look past the green tick.

The questions they asked were the right ones. Can you trust a CDN-masked carbon score? Is green hosting really green? What about the rest of the supply chain? The honest answer to all three is still: it's complicated.

What's changed is that the tools now exist to give you a more granular, more honest answer. Not a perfect one — but a transparent one, with methodology you can interrogate and data sources you can verify.

That's worth something.

EcoPigs is a website carbon measurement engine built by OYNK. It powers the emissions analysis behind our PEER Audit reports, giving businesses accurate, location-aware carbon data for their digital presence.