Effective carbon removal accounting requires well-defined system boundaries and a complete understanding of emissions resulting from project operations and material sourcing. All carbon sources, sinks, and reservoirs (SSRs) within the system and project boundaries have been identified according to the ISO 14064-2 framework for identifying and selecting greenhouse gas SSRs for regular monitoring or estimating GHG emissions or removals.
Emissions associated with each deployment are directly correlated to where project boundaries are drawn in relation to company operations, and as such must be clearly defined and stated to avoid misrepresenting system efficacy and total climatic impact. Project emissions are the portion of total company emissions directly related to intervention operations and deployment, as shown in the illustrative graphic below:
Figure 3: Illustrative carbon accounting for company versus project-level emissions over the course of five hypothetical carbon removal projects. Notably, based on the GHG Protocol’s Draft Land Sector and Removals Guidance, there are no Scope 2 removals, since removals do not occur in the generation of electricity, steam, heating or cooling, and any removals occurring in the value chain of the energy generation process are accounted for in Scope 3.
As the size and scope of the project expands, it will begin to encompass additional company emissions and broader sourcing considerations. Emissions sources currently identified within the project boundary, in line with ISO SSR requirements, include the following:
Upstream transportation and distribution of materials to production sites.
Production and processing of materials that are a direct result of project sourcing.
Considerations of direct or indirect land-use changes resulting from sourcing materials.
Production Site Operations
Energy use for the production of carbon buoys.
Emissions associated with capital equipment purchases and site construction.
Contractor activities including maintenance and equipment setup.
Energy use for loading and transportation of the deployment vessel.
Other Production Sites (Macroalgae Hatchery and Verification Hardware Development)
Energy use for production operations.
Construction, equipment purchases, and maintenance.
Cradle-to-gate emissions of raw materials.
Upstream transportation & distribution of materials and equipment.
In addition to the categories listed above, any other emissions sources that are directly related to project operations such as data center use should be evaluated for materiality and included in deployment reporting. Both company and project emissions accounting are performed under the Greenhouse Gas Protocol. In addition, any life cycle assessments (LCAs) utilized in emissions calculations must be verified by a third party, and where possible, supported by supplier records.
Figure 4. Intervention system process flow, including likely CO2e sources, sinks, and reservoirs within the project boundaries.
For all deployments, conservative standard emissions factors and discount rates will be utilized where project emission sources cannot be directly measured. In the event there is not a clear line between project and company emissions within the defined project boundary, emissions will be reasonably applied to the project level to ensure conservative accounting.
Project-related emissions associated with capital goods will be amortized over a maximum of 12 months from the in-service date. Construction in progress ongoing for longer than 12 months will commence amortization on a rolling basis until the asset is put into service, at which point the remaining emissions liability will be recognized in line with the standard amortization policy. All project emissions liabilities will be recognized in project carbon accounting to net the metric tons of CO2e removed during a project.
A short amortization period is a unique approach for project-level CapEx carbon accounting. This approach ensures that the carbon removal project recognizes emissions carbon liabilities on a time frame where the emissions do not have a material, compounding negative effect on the planet. As a result, this liability can be recognized and removed from the emitter’s balance sheet when balanced by the carbon removed during project operations.