A carbon footprint is the total greenhouse gas emissions caused by a person, product or company, usually expressed in tons of carbon dioxide equivalent. For business, the count follows a standard set of three scopes.
Scope 1: direct emissions
These come from sources the company owns or controls, such as fuel burned in boilers, backup generators and company vehicles.
Scope 2: purchased energy
These come from the electricity, steam, heating or cooling a company buys. For data centers, Scope 2 is often the biggest number, because they use so much power.
Scope 3: everything else
Scope 3 covers the rest of the chain: suppliers, shipping, business travel, and what customers do with the product. It is usually the largest share and the hardest to measure. The Greenhouse Gas Protocol publishes the standards most companies follow.
How companies shrink the number
Common steps include improving efficiency, buying cleaner power, redesigning products and asking suppliers for data. The EPA offers calculators and guidance for organizations just starting to measure.
What to watch in the news
When a company says it is carbon neutral or net zero, ask which scopes are included, which year is the baseline, and whether the cuts are real or bought as offsets.
Related reading
Keep going with more explainers in Eco Explained, or see the latest in News.
