What Makes a High-Quality Carbon Offset?

Questions for Buyers to Ask About Overestimation

Examining in detail how a project’s GHG reductions were quantified can be difficult and time-consuming. However, two relatively straightforward questions can point to areas of potential risk:

  • Does the project apply any deviations from the protocol/methodology and appropriately justify these deviations? Several carbon offset programs allow projects to deviate from a protocol’s requirements if the project developer can justify an alternative approach to program staff. Deviations are often temporary, and typically involve situations where a project is not able to produce monitoring data according to prescribed methods, but is able to estimate them using alternative methods. Programs will generally try to ensure that alternative methods are more conservative than what a protocol prescribes. Offset credit buyers may nevertheless wish to review cases where a deviation was applied for and approved.
  • Are there any gaps or other discrepancies in project monitoring data, and have these discrepancies been properly explained and addressed? Major carbon offset programs have rules and procedures to address gaps or discrepancies in project monitoring data (for example, if a flow meter temporarily breaks down and fails to collect data for a period of time). Such instances should be transparently reported, along with methods to address them. If monitoring reports and relevant data are not available and easily accessible (usually online), this lack of transparency should raise concerns about overestimation.