Methodology for net avoided emissions

In 2024, SMG partnered with an independent climate tech company to conduct our first-ever estimation of net avoided emissions resulting from second-hand transactions across our three General Marketplaces: Ricardo, anibis.ch, and tutti.ch. This builds on earlier efforts to estimate and display indicative carbon savings at item level on Ricardo listings. The 2024 analysis uses an improved methodology, offering a more comprehensive and consolidated view of the net climate benefits enabled by circular consumption across our platforms.

The full methodology and detailed results will be published in our 2024 Avoided Emissions Report.

Consequential LCA approach

The estimation follows a consequential Life Cycle Assessment (LCA) method, aligned with internationally recognised guidance from the World Resources Institute (WRI). By combining real marketplace activity data with extensive survey input from buyers and sellers, we can accurately assess how second-hand shopping displaces new purchases, and how much carbon it avoids.

The analysis incorporates three key components:

• Alternative scenario emissions
  The full cradle-to-consumer footprint of a new product that would have been purchased instead. This includes emissions from raw material extraction, manufacturing, distribution, and final delivery.
• Replacement rate
  The proportion of second-hand purchases that actually displaced the purchase of a new product, based on user-reported behaviour. This metric varies by product category.
• Emissions from second-hand transactions
  The carbon footprint associated with the second-hand exchange itself, including: delivery emissions (e.g. post, local pick-up), packaging emissions, and SMG's operational emissions related to facilitating the transaction

The survey data informs the replacement rate, but also provides granular inputs on user behaviour, such as delivery methods and packaging choices, which directly influence the emissions associated with second-hand transactions. This integration of behavioural science strengthens the credibility and accuracy of the estimation.

The avoided emissions were determined using the following logic:

Net avoided emissions
= (Alternative scenario emissions × Replacement rate (%))
− Emissions from second-hand transactions

This methodology ensures that SMG’s contribution to circularity and climate mitigation is measurable, transparent, and grounded in scientific best practice.