Climate ActionDecember 2, 2023by

Buffer Pools: Safeguarding the Integrity of Nature-Based Carbon Credits


In the pursuit of addressing climate change and reducing greenhouse gas emissions, nature-based carbon credits have emerged as a powerful tool. These credits, generated through activities like afforestation, reforestation, and conservation projects, have the potential to provide up to 30% of the global climate mitigation required to limit global warming to 1.5 degrees, as highlighted by the UN Global Compact. Notably, buffer pools are primarily utilized in nature-based carbon credit initiatives, which face a higher likelihood of reversals compared to technology-based carbon reduction solutions. However, ensuring the integrity of these credits and minimizing risks associated with their issuance is crucial to their effectiveness. In this context, buffer pools play a pivotal role, functioning as a risk management mechanism that can significantly impact the landscape of climate action.

Buffer pools are a critical component of nature-based carbon credits, serving as a safeguard to ensure the long-term effectiveness and integrity of these credits. By mitigating the risks associated with their issuance, buffer pools contribute to the sustainability and credibility of carbon credit programs. They hold the potential to support climate change mitigation efforts by de-risking the transition of companies and industries towards low-carbon practices.

In essence, buffer pools can be likened to insurance policies for carbon credits. Their primary purpose is to guarantee that each carbon credit will represent the removal or avoidance of 1 ton of CO2 emissions, even in the face of unexpected carbon stock losses. This risk management mechanism provides a safety net, ensuring that the environmental benefits associated with these credits are not compromised.

To understand the role of buffer pools more concretely, it’s essential to grasp how they function. Instead of immediately selling all generated carbon credits, a portion is set aside and placed in a designated buffer pool. This strategic move ensures that, in the event of a reversal, buffer credits can be drawn upon to uphold the credibility of previously issued credits.

A reversal in the context of carbon credit projects involves the re-emission of greenhouse gases that had been previously sequestered or prevented by the project, raising doubts about the validity of the credits issued. These reversals can be triggered by various factors, such as human activities like logging, forest fires, and environmental factors like droughts

The potential impact of buffer pools extends to the realm of insurance markets. It is estimated that by 2030, these risk management mechanisms could contribute to the growth of a substantial insurance market, with projections reaching up to USD1.3 billion. This development reflects the increasing recognition of the importance of safeguarding the long-term benefits of nature-based carbon credits.

The registry is responsible for overseeing the management of the buffer pool. It has the option to consolidate buffer credits from all projects within the registry program into a unified pool, which may be categorized by project type. Alternatively, the registry can choose to link the buffer pool directly to specific projects on an individual basis.

In the context of carbon credit projects, it is important to note that, not every instance of carbon stock loss within a project area will lead to the removal of credits from the buffer pool. Specifically, if a project demonstrates a net reduction or removal of emissions throughout a crediting period, credits will be exempt from cancellation within the buffer pool. Additionally, in situations where there is no net loss of carbon stock during the subsequent verification, and the project has achieved a surplus of emissions reductions or removals compared to losses, buffer pools will not be triggered.

When a net loss of carbon stock is identified during verification, credits can be removed from the buffer pool. The response measures depend on the registry overseeing the carbon credit program. In instances where the loss of credits is extensive, surpassing the project’s contributions to the buffer pool, or if the project is terminated, the liability and corresponding actions differ depending on the registry. For example:

  • The American Carbon Registry requires projects to either acquire credits from another project or cancel credits from the buffer pool. This cancellation should equate to the total number of credits ever issued by the project.
  • Verra, on the other hand, mandates the cancellation of credits exclusively from the buffer pool. In exceptional cases, where a project is terminated prematurely or fails to submit a verification report for 15 years, all credits ever sold by the project will be removed from the buffer pool.

In Verra, projects that exhibit outstanding performance are eligible to recover a portion of their buffer credits. This initiative allows for the release of up to 15% of the project’s buffer pool credits, provided the project demonstrates consistent exceptional performance over a 5-year monitoring period. Such performance is defined by either a decrease in the project’s risk score or a reduced reliance on the buffer. It is crucial to note that this release can only take place after a minimum of 5 years from the initial verification of the credits.

Understanding how these contributions are classified is essential for project proponents and stakeholders alike. Contributions to the buffer pool can occur either directly from a project’s issuance, or in the case of project proponents having the flexibility to input credits from another project. These contributions rates can be categorized into two main types of buffer pool contributions:

  1. Standard Flat Rate: Some contributions adhere to a standard flat rate, which may be subject to adjustments. For example, the Gold Standard imposes a flat rate of 20% as the contribution.
  2. Risk-Adjusted Basis: Contributions for certain projects are determined on a risk-adjusted basis. These determinations are subject to minimum thresholds set by registries, such as Verra, which sets the threshold at a minimum of 10%.

In instances where contributions are contingent on risk assessments, the specific project’s amount contribution is determined by the outcomes of non-permanence risk assessments conducted during each monitoring period. For select registries, such as Verra, a project’s contribution to the buffer pool per issuance may fluctuate over time based on the project’s identified risks during each monitoring period, and after any credits have been cancelled from the buffer pool.

Projects are motivated to minimize their contributions to and reliance on the buffer pool when contributions are linked to project-specific non-permanence risk assessments. This approach is designed to maximize the volume of credits available for sale, thereby optimizing revenue for the project.

Assessing the efficiency of a project’s risk buffer contribution hinges on the transparency of non-permanence risk assessments for nature-based projects. However, the current risk buffer mechanisms fall short in accounting for variations in credit quality, highlighting the pressing need for alternative insurance tools tailored to nature-based credits.

The Voluntary Carbon Market is currently experiencing heightened scrutiny across various domains, including the design and operation of buffer pools. Consequently, both registries and market bodies are taking proactive steps to revise buffer pool requirements and non-permanence risk modeling, aligning them with the latest scientific advancements. With concurrent progress in Monitoring, Reporting, and Verification (MRV) technology, broader improvements in certification methodologies, and the emergence of insurance products tailored to carbon credits, there will be substantial strengthening of the resilience of both carbon credits and buffer pools moving forward.


Author: Victor O. Nyakinda