The Mass Balance Chain of Custody model

The mass balance approach is primarily associated with tracking the flow of materials through a series of processes or across different stages of the supply chain, often used in the context of sustainable material sourcing or recycling.

This method allocates the input of mixed materials (such as recycled and non-recycled content) across the output products in proportion to their mass. The exact mass of sustainable material must be certified and tracked along the supply chain and reconciled to reflect the ratio of sustainable material integrated into the final product. This serves to back up sustainability claims such as, “made with 90% recycled plastic” although customers have no way of knowing if the final product actually contains any molecules of the sustainable materials or not.

‍

This approach is most common for products and commodities where segregation is very difficult or impossible to achieve, such as in the plastics and petrochemical industry, but also utilised in other segments like transport and metals supply chains. Principles of mass balance can be indirectly relevant to GHG accounting in specific contexts, such as:

‍

Recycled and Recyclable Materials

In scenarios where the use of recycled materials influences the GHG emissions associated with a product or process, considering the reduced impact of using recycled versus virgin materials.

‍

Scope 3 Emissions

For companies calculating their value chain (Scope 3) emissions, especially when assessing emissions associated with purchased goods and services, fuel used in transport and end-of-life treatment of sold products.

‍

The mass balance approach might inform the allocation of emissions in complex supply chains. CarbonLeap makes tracking, tracing, compliance and verification of the mass balance principle possible for fuel usage. This process is supported by our Carbon Bank using state of the art digital technology powered by SAP.

‍