Consider Digital presents
Every web page you have ever loaded was powered by a real power station, somewhere. This is the story of that journey — and of the carbon it quietly carries.
this page practises what it preaches —
no images · no webfonts · no tracking · one small file
01 · Generation
Britain's grid is cleaner than it has ever been — and in 2024, wind generated more electricity than gas for the first time. But every kilowatt-hour still carries a carbon cost, and that intensity changes hour by hour with demand, weather and the generation mix.
GB grid average, 2024 · ≈ 125 g CO₂ per kWh
every byte you ship spends some of it
02 · Transmission
From the turbine, electricity is stepped up and sent across the country on the transmission network, then stepped down, again and again, until it reaches a socket — and the router, mast and phone plugged into it.
≈ 8% of the energy is lost as heat
before it ever reaches a plug
03 · The request
In a few dozen milliseconds your request crosses the network to a data centre, and the page streams back — byte by byte, through machines that never sleep. Distance matters: the further your data travels, the more energy the journey takes.
where a page's energy is spent
≈ ½ your device · ¼ the network · ¼ data centres
sustainable web design model, estimates
04 · The page itself
Pull the median web page apart and you find ≈ 2.7 MB — most of it images and JavaScript, much of it never noticed by the person reading.
one view of a typical page
≈ 0.5 g CO₂e · feels like nothing — keep scrolling
a modest site, one year
120,000 views ≈ 60 kg CO₂e — like driving 220 miles in a petrol car.
at a million views a month, it's tonnes — and there are over a billion websites.
multiply it out, and the web's little pages add up to a significant amount of carbon.
06 · An analogy
Swap one bulb for an LED and the grid never notices. Swap every bulb in the country and it adds up to a significant change.
Web pages work on exactly the same maths. One page is grams. The web is megatonnes. Every little helps — because there is an enormous amount of little.
07 · The whole web
…it would be among the largest electricity consumers on Earth. Digital technology is estimated to drive 2–4% of global emissions — in the same league as aviation.
And it is gaining weight. The median page has roughly tripled in size since 2012: more script, more imagery, more video — rarely more useful.
median page weight
0.8 MB (2012) → 1.9 MB (2018) → 2.7 MB (today)
08 · Lighter is a choice
Modern formats, right-sized. The single biggest saving on most pages.
Every kilobyte is shipped, parsed and run — on the reader's battery.
Beautiful type is already on every device. This page ships zero font bytes.
Never autoplay. A poster frame and a click saves megabytes per visit.
Serve from data centres running on renewables. Same site, cleaner watts.
Sites gain weight silently — every upload, plugin and rebuild adds up. Measure, monthly.
the LED moment for the web —
lighter pages, at scale, are a real climate lever
Consider · Digital
We test websites for their CO₂ footprint and run ongoing audits that catch bloat before it ships — unoptimised images, creeping scripts, forgotten video — so your site stays as light as the day it launched.
Test your site's CO₂ →Sources & workings: NESO / National Grid ESO generation data (2024) · HTTP Archive page-weight medians · Sustainable Web Design model v4 · websitecarbon.com. Figures are rounded — the point survives the rounding.