Emissions Get Split Into Three Scopes and the Boundary Does the Work
Scope 1 is what you burn, Scope 2 is the power you buy, Scope 3 is everyone else in your value chain. The boundaries decide whether a number is impressive or meaningless.
Why a Standard Was Needed
Before 2001 companies reporting emissions used whatever boundaries they preferred, which made two disclosures impossible to compare. The Greenhouse Gas Protocol, written by the World Resources Institute and the World Business Council for Sustainable Development, imposed a common structure.
Its central move was to split emissions by who controls the source. That single decision drives everything else.
The Three Scopes
| Scope | What it covers | Typical example |
|---|---|---|
| Scope 1 | Direct, from sources the company owns or controls | Furnaces, company vehicles, process emissions |
| Scope 2 | Indirect, from purchased electricity, steam, heat | Grid power for offices and plants |
| Scope 3 | Indirect, everything else up and down the chain | Suppliers, business travel, product use, disposal |
Scope 1 and Scope 2 are mandatory under the standard. Scope 3 is where the mass usually sits and it is the hardest to measure, which is why it is so often reported partially or not at all.
The Scope 2 Trick Worth Knowing
There are two legitimate ways to compute Scope 2 and they can produce very different answers.
Location based uses the average emissions intensity of the grid the facility physically sits on. Market based uses the emissions attached to the electricity the company contractually purchased, which lets renewable energy certificates and power purchase agreements reduce the reported figure.
A company can buy certificates, report a market based Scope 2 near zero, and draw exactly the same electrons from exactly the same coal heavy grid as before.
When a company announces its electricity is one hundred percent renewable, it is almost always making a contractual claim, not a physical one. Both numbers are real. They answer different questions.
Intensity Versus Absolute
The second place boundaries do heavy lifting is the denominator. An absolute target commits to total tonnes falling. An intensity target commits to tonnes per unit of revenue, per unit of output, or per employee.
A company growing quickly can improve intensity every year while total emissions rise. Both statements are true simultaneously and only one of them matters to the atmosphere.
Where the Numbers Come From
Very little of this is metered. Most emissions figures are activity data multiplied by an emission factor: litres of fuel times a factor, dollars spent with a supplier category times a factor, kilometres flown times a factor.
Spend based factors are the crudest. They assume every dollar spent in an industry carries the same emissions, so a company that switches to a cleaner supplier at the same price shows no improvement at all.
This is why restatements are common and why comparing two companies at the same reported tonnage tells you less than it appears to.
What Actually Changes a Reported Number
Four things reduce reported emissions, and only two of them are operational improvements.
Real reductions come from using less energy or switching to cleaner inputs. The other two are boundary effects: divesting a dirty business moves the emissions to someone else balance, and changing methodology or emission factors can shift a figure by double digit percentages with no physical change.
Reading the methodology note and the restatement history is the whole job.
The Bottom Line
The three scope framework is an accounting convention that defines control boundaries, not a measurement technology. Scope 2 has two valid answers, intensity targets can improve while absolutes rise, and most underlying figures are estimates from spend multiplied by a factor. Any climate claim should be read the way you read a non standard earnings metric: check the boundary before you check the number.