To be aligned with the Global Protocol for Community-Scale Greenhouse Gas Inventories (GPC), users must first define an inventory boundary to identify the geographic area, time span, gases, and emission sources. Any geographic boundary may be used. The GPC is designed to account for greenhouse gas emissions in a single reporting year and includes the seven gases covered by the Kyoto Protocol. The GPC groups emissions into three categories based on where they occur: scope 1, scope 2 or scope 3 emissions.
Scope 1: Greenhouse gas emissions from sources within the geographic boundary Scope 2: Greenhouse gas emissions occurring as a consequence of the use of grid-supplied electricity, heat, steam and/or cooling within the boundary. Scope 3: All other greenhouse gas emissions that occur outside the boundary as a result of activities taking places within the boundary