Most people want one number. In the digital emissions vs physical emissions question, is the digital side bigger, yes or no?
The honest reply is that the question is unanswerable as asked, and that is not evasion. It depends entirely on what you include on each side, and almost every confident comparison you will read has quietly chosen boundaries that produce the answer it wanted.
Getting this right matters commercially, because a business that reports on the wrong boundary is either overstating or understating its position, and both are problems.
Digital Emissions vs Physical Emissions: A UK Guide
1. Why the comparison keeps going wrong
- Scope is rarely stated. Does digital include the manufacture of every device your customers use to reach you? Does physical include your suppliers’ logistics? Two comparisons using different boundaries are not comparable, and neither is wrong.
- Double counting is common. A laptop used for work appears in an office energy figure and in a digital footprint calculation. Counted twice, the total is wrong.
- Averages hide enormous variation. A business running data-intensive services has a very different profile from a consultancy with a brochure site. Sector averages describe neither.
- Manufacturing dominates and gets ignored. For most organisations, the largest digital-related impact is making the devices, not running them. Comparisons focused on electricity miss the biggest component.
2. What belongs on the digital emissions side
Broadly: the energy to run your website and services, the network transfer to reach people, the processing on their devices, your own hardware and its manufacture, and the cloud services you consume.
The manufacturing point deserves emphasis. Extending a laptop’s working life from three years to five will usually outweigh anything you do to the software running on it, and it is the least discussed measure in this whole subject.
3. What belongs on the physical emissions side
Premises energy, travel, logistics, materials, waste, and whatever your supply chain contributes.
The boundary question bites hardest here. Whether supplier emissions count depends on the reporting framework you are using, and that decision changes your total substantially.
4. Where digital emissions replaces physical emissions
This is the genuinely interesting case, and it is where digital work has its clearest environmental argument.
A video call instead of a drive to Bristol. An online form instead of a posted document. A digital manual instead of a printed one distributed nationally.
These are real substitutions with real reductions, and they are far more defensible than claims about website efficiency, because the avoided activity is concrete and quantifiable in a way that modelled digital carbon is not.
5. Where digital emissions adds without replacing
The counterpart, which gets less attention.
A video autoplaying on every page load that replaces nothing. Analytics tools duplicating each other. Content nobody reads, stored and served indefinitely. Devices replaced on a cycle rather than at end of life.
Digital activity that substitutes for physical activity generally reduces impact. Digital activity added on top generally increases it. That distinction is more useful than any comparison of totals.
Where to actually start your emissions comparison
With what you control and can measure.
Record page weight, request count and Core Web Vitals for your most-visited pages under stated conditions. Take a carbon estimate from the same pages with the same tool.
Reducing unnecessary data transfer and processing supports a faster experience while lowering estimated digital carbon, though those environmental figures remain modelled rather than directly measured. That caveat belongs in anything you publish.
Then look at the website lifecycle, which is probably larger and is rarely examined.
Before you report any of it
Before you report any of itEnvironmental claims must be accurate and substantiated. The Competition and Markets Authority’s Green Claims Code sets out the standard.
State your boundary explicitly. A figure without a stated scope is not a figure, and any assessor who knows the subject will ask.
Our website sustainability audits cover the website-related portion with the method and boundary documented, which is the part you can defend.