GPC Standard Explained: How Municipalities Create GHG Inventories

The GPC is the international standard for how cities and municipalities measure and report greenhouse gas emissions. Developed by WRI, C40, and ICLEI, it provides a consistent framework that makes data comparable across cities worldwide.

Inventory Boundaries

BASIC covers Scope 1 and 2 from stationary energy, transportation, and waste. BASIC+ adds Scope 3, industrial processes, and agriculture/forestry.

The Five GPC Sectors

1. Stationary Energy: Buildings and facilities — residential, commercial, institutional, manufacturing
2. Transportation: On-road, rail, waterborne, aviation within city boundaries
3. Waste: Landfills, biological treatment, incineration, wastewater
4. IPPU: Industrial processes and product use (BASIC+ only)
5. AFOLU: Agriculture, forestry, and land use (BASIC+ only)

Notation Keys

The GPC provides standardized ways to handle data gaps: IE (Included Elsewhere), NE (Not Estimated), NO (Not Occurring), C (Confidential). This transparency about gaps builds credibility.

Getting Started

1. Define your geographic boundary
2. Choose BASIC or BASIC+
3. Identify data sources — utilities, transport authorities, waste management
4. Collect activity data for each sector
5. Apply emission factors from nationally recognized sources
6. Document notation keys for gaps
7. Calculate and report