Ex-ante vs ex-post carbon credits

• Ex-ante credits → issued based on expected future carbon capture

• Ex-post credits → issued after carbon capture has been measured

Both approaches are used in the voluntary carbon market, each with different implications.

1. Ex-post credits

Ex-post credits are issued after carbon has already been captured and verified.

How it works

• Trees grow over time

• Carbon capture is measured periodically

• Credits are issued only once results are confirmed

Advantages

• High level of certainty at the time of issuance

• Widely accepted in traditional carbon markets

Limitations

• Very slow process (often years before credits are issued)

• Requires significant upfront funding without immediate return

• Limits the ability to scale early-stage or nature-based projects

• Does not directly fund new planting, as credits are issued after the impact has already occurred

2. Ex-ante credits

Ex-ante credits are issued at the start of a project, based on projected carbon capture.

How it works

• Expected carbon capture is calculated using scientific models

• Credits are issued upfront

• Project performance is tracked over time

Advantages

• Immediate funding for projects

• Enables faster scaling of reforestation efforts

• Aligns incentives between project developers and sponsors

Considerations

• Based on projections rather than measured outcomes at issuance

• Requires strong systems to ensure delivery over time

3. Tree-Nation’s approach

Tree-Nation uses an ex-ante model, combined with continuous verification.

Key principles

• Carbon estimates are based on species-specific data and conservative assumptions

• Credits are issued at project validation through Project Design Documents (PDDs)

• Each PDD defines:

  • Number of trees

  • Expected carbon capture

  • Delivery timeline

   

This approach ensures that projects receive immediate funding to enable new planting, while performance is continuously verified over time based on real outcomes.

In practice, this means Tree-Nation combines the causality of ex-ante (funding new projects) with the accountability of ex-post (measured and verified performance).

4. Managing delivery over time

Instead of relying only on delayed issuance, Tree-Nation ensures credibility through:

Continuous verification

• Projects are monitored through verification events over time

• Includes:

  • Geolocated planting data

  • Satellite monitoring and remote sensing (e.g. vegetation indices)

  • Field updates and project reporting

   

Dynamic performance tracking

• Project performance is assessed continuously, not just once

• Deviations can be identified and addressed early

Long-term commitment

• Projects are subject to annual verification during the certified monitoring period (5 years for Mission, 10 years for Foundation). Beyond this period, Tree-Nation may continue to monitor project performance through remote sensing for up to 20 years to support long-term ecosystem observation and potential ex-post carbon accounting.

5. Two different models of trust

The difference between both approaches can be summarized as:

• Ex-post model

  → trust is based on waiting for confirmed results

• Ex-ante model

  → trust is based on system design, conservative estimates, and continuous monitoring

In summary

Both approaches aim to ensure a credible carbon impact:

• Ex-post prioritizes certainty at issuance

• Ex-ante prioritizes early funding and scalability

Tree-Nation’s model combines:

• Conservative projections at issuance

• With continuous verification and transparent monitoring over time

This allows projects to scale while maintaining accountability throughout their lifecycle.