Isometric recently released a draft module for greenhouse gas (GHG) accounting in carbon removal for public consultation. This module would provide a universal framework for GHG emissions accounting—designed to elevate scientific rigor and transparency—that can be applied across all carbon removal pathways.
Robust GHG accounting makes it possible to quantify and provide evidence for carbon removal activities. It is essential for understanding the full impact of a carbon removal project on the levels of carbon dioxide and other GHGs in the atmosphere. It involves tracking all emissions and removals associated with every phase of the project—including those generated during project establishment, operation, and end-of-life.
When producing credits, a project's emissions, removals and, counterfactual removals—the removals that would have taken place in the baseline scenario—must be presented together in net metric tonnes of carbon dioxide equivalent, as part of a GHG Statement. This approach helps ensure that every Isometric credit represents one tonne of carbon dioxide durably removed from the atmosphere.
Net removals = project removals - baseline removals - project emissions
Currently, GHG accounting requirements are embedded within individual Isometric protocols and energy, transportation, and embodied emissions accounting modules. The GHG Accounting Module would change this by applying consistent requirements across all pathways and acting as a single source of truth, ensuring consistency, transparency, and scientific rigor.
The draft module consolidates a number of requirements already found in Isometric’s protocols and introduces additions to enhance accuracy, transparency, and rigor. Each addition has been developed following a robust empirical approach, using real-world data and with careful consideration of application across different carbon removal pathways.
- A clear framework for what constitutes high-quality GHG emissions data. By following these new requirements, suppliers can reduce uncertainty in GHG assessments.
- A threshold for determining the significance and materiality of GHG emissions from project activities—enabling suppliers to prioritize collecting data that increases the accuracy of their GHG accounting, rather than chasing data that has a negligible contribution to project emissions.
- Requirements for how GHG emissions should be allocated when carbon removal is a co-product of a process or when the removed carbon dioxide is stored within a product.
- For projects that amortize emissions over time—where GHG emissions produced during the development or construction of a project are accounted for over a period of time—this module would introduce new mechanisms that reduce the risk of emissions not being accounted for over a project’s operation.
Isometric’s draft GHG Accounting Module represents a significant step toward a consistent and transparent system for assessing the climate impact of carbon removal projects and will continue to evolve as scientific understanding and data collection technologies improve.
To support effective implementation, a six-month grace period is proposed following certification, to give projects time to adapt processes and reporting.
The module was developed in line with the Isometric Standard and was created in collaboration between Isometric’s in-house Science Team and reviewers from Isometric’s independent Science Network of over 300 scientific experts. Comments on this module are welcome from interested buyers, suppliers, and scientists during the 30-day public consultation period which ends on June 9, 2025.
