Emissions Inventory

An emissions inventory (or GHG inventory) is a systematic, quantified record of all the greenhouse gas (GHG) emissions generated by an organisation, territory, project or product over a defined period. It is the foundation of climate accounting, target setting and sustainability reporting: you cannot manage or reduce what you have not first measured.

What it is for

• Transparency and accountability towards stakeholders.
• Identifying the hotspots where mitigation will have most effect.
• Regulatory compliance and participation in carbon markets.

Methodological frameworks

• GHG Protocol Corporate Standard, covering Scope 1, Scope 2 and Scope 3 emissions.
• ISO 14064-1 for quantification and reporting at organisation level.
• IPCC Guidelines for national inventories.

How an inventory is built

1. Set the boundaries: choose the consolidation approach (equity share, financial or operational control).
2. Collect activity data: fuels, electricity (kWh), distance travelled, tonnes of material.
3. Apply emission factors: from recognised sources such as the IPCC, the IEA or national datasets.
4. Calculate and consolidate results in CO2 equivalent (CO2e).
5. Verify internally or through an independent third party.
6. Report through frameworks such as CDP or under sustainability-reporting standards.

Reporting context

GHG inventories increasingly feed formal disclosure. The TCFD task force was disbanded in 2023 and its climate-related recommendations have been consolidated into IFRS S2, with monitoring taken over by the ISSB under the IFRS Foundation, while in the EU the CSRD and the ESRS require emissions data. In Spain, Royal Decree 214/2025 requires companies within its scope to calculate their Scope 1 and 2 emissions (Scope 3 remains voluntary) and to have a five-year reduction plan with quantified targets.

Challenges

• Data quality for Scope 3, which is often the largest and hardest part to measure.
• The internal resources needed to collect and manage the data.
• Methodological changes that require historical figures to be restated.

An accurate emissions inventory is the starting point for corporate climate management, for setting science-based targets and for credible communication. At Manglai we help companies build and maintain their GHG inventory across all three scopes. Discover Manglai's carbon footprint software.