Organizations often know they need a GHG inventory but are unsure where to begin. The answer is to establish the inventory boundary first, then systematically identify sources and activity data.
Scope 1: direct emissions
Scope 1 covers direct emissions from sources owned or controlled by the reporting organization. Examples include fuel combustion in owned equipment and certain process emissions.
Scope 2: purchased energy
Scope 2 covers indirect emissions associated with purchased electricity, steam, heat and cooling. The accounting approach needs to match the reporting context and available contractual or grid information.
Scope 3: the value chain
Scope 3 covers other indirect emissions in the organization’s value chain. It can be the most data-intensive part of an inventory, so screening and prioritization are often useful first steps.
A practical starting sequence
- Define the organizational boundary.
- Map major emissions sources.
- Identify available activity data.
- Select appropriate emissions factors.
- Calculate and quality-check the inventory.
- Use the results to identify material reduction opportunities.
