Greenhouse Gas Protocol update would provide guidance on GWPs

The WBCSD/WRI recently proposed an update to their Corporate Greenhouse Gas Protocol to provide specific regulations regarding the global warming potential (GWP) values used by companies seeking compliance with the standard.

Unlike the more recent Product and Scope 3 standards, the Corporate standard does not currently include specifications or guidance related to the selection and use of GWPs in organizational GHG assessments. The proposed amendment would align the Corporate standard with the Product and Scope 3 standards in requiring the use of 100-year GWP values published by the IPCC.

Furthermore, the WBCSD/WRI has proposed recommending that any company conducting an assessment for the first time use GWP values published in the IPCC’s most recent Assessment Report, which at this time is the 4^th Assessment Report (AR4). Companies that have previously conducted an assessment using GWP values in the 2^nd Assessment Report could continue using these values, provided that they are 100-year figures. Lastly, the source of the GWP values must be reported in the company’s assessment.

It’s interesting to note that the change will have implications for Defra/DECC’s conversion factors for company reporting, which currently provide emission factors for CH₄ and N₂O in CO₂e using the 2^nd Assessment Report GWPs. Reporting companies will need to convert the kgCO₂e factors into kgCH₄ and kgN₂O using the 2^nd Assessment Report GWPs, and then convert back to kgCO₂e using the 4^th Assessment Report GWPs (assuming they opt to use latest GWPs). Alternatively, it would be helpful if Defra/DECC published base factors for kgCH₄ and kgN₂O rather than kgCO₂e, allowing reporting companies to choose which GWPs they want to apply.

The open comment period enabling stakeholders to provide feedback on the proposed changes ended July 29^th. If accepted, the amended standard should be used for all new GHG assessments prepared for the next year of reporting seeking compliance with the WBCSD/WRI Corporate Greenhouse Gas Protocol.