The “vintage” of an carbon credit can refer either to the year in which it was issued, or the year in which its associated avoided GHG emissions or enhanced removals occurred (for some kinds of carbon credit projects, there can be a significant lag between the emissions impact and issuance, because of longer verification cycles, e.g., with forestry projects). Older issuance vintages may present a quality concern where the following conditions are true:
- The carbon credits under consideration have remained unsold for a long time; and/or
- The carbon credits are being sold directly by the project developer, where the developer:
- Did not contract with a dedicated carbon credit buyer upfront (e.g., under an ERPA); and/or
- Has carried forward a significant number of unsold carbon credits; and
- Has continued to operate the carbon project for several years despite the lack of carbon credit sales.
Pros: Avoiding the purchase of older credit vintages can avoid cases where credits were obviously lower-quality to begin with. It may also help to ensure that your purchase is driving new efforts to avoid emissions or enhance removals. (Even if an old project was high-quality to begin with, if it is now complete or near completion, or it has succeeded for years without selling some credits, then buying unsold credits may not contribute to addressing climate change beyond merely supporting a “sunk” benefit of the project.)
Cons: The vintage of a carbon credit does not by itself indicate anything about its quality.