Analysis finds 80 per cent of offsets from major voluntary carbon market projects in 2024 unlikely to deliver promised emissions reductions

A new report titled ‘Built to Fail? World’s largest carbon offset projects unlikely to deliver promised emissions reductions despite ongoing reforms’ raises significant concerns about the credibility and effectiveness of the voluntary carbon market (VCM), suggesting that the current system may be exacerbating the risk of climate action failure rather than mitigating it.

The study, which analysed 47 of the world’s largest offset projects retired in 2024, finds that over 47.7 million carbon credits—representing about 80 per cent of those retired from these projects—were classified as problematic. These credits are deemed unlikely to deliver the promised emissions reductions, despite the recent wave of reforms known as VCM 2.0.

The report underscores that these problematic projects account for nearly a quarter of all credits retired in the VCM in 2024. It further highlights that 93 per cent of these projects are located in the Global South, including countries such as Brazil—host of the upcoming COP30 climate summit—Cambodia, and Turkey.

Using project risk assessments from carbon credit rating agency BeZero, the study examined the potential for fundamental failings across 37 of the 43 problematic projects. These included concerns over non-additionality, non-permanence, leakage, and over-crediting. 23 projects had a legitimate or high risk of being non-additional, meaning the emissions reductions would have occurred even without the project. 14 projects had risks associated with non-permanence, such as the possibility that carbon storage could be reversed.

While none of the 47 projects had the highest possible BeZero rating (AAA), only four projects were rated as having a higher than moderate likelihood of delivering 1 tonne of CO₂e avoidance or removal. Even these, the report notes, carried legitimate risks of failure.

Major Registries And Verifiers Under Scrutiny
According to the research, Verra, the world’s largest carbon offset registry, issued over 90 per cent (43.6 million) of the problematic credits analysed. The report questions whether Verra’s recent updates to its methodologies have been sufficient to prevent systemic flaws.

Other registries named in the report include the Gold Standard Impact Registry, Climate Action Reserve, and ACR, which together issued an additional 4.1 million problematic credits.

The analysis also identified 17 different third-party verifiers involved in approving these projects, raising concerns about the effectiveness of existing certification and oversight mechanisms within the VCM. The report suggests that the system’s current “checks and balances” are not stringent enough to prevent flawed credits from entering the market at scale.

Of the 43 problematic projects, the majority were forestry and land use projects (23) and renewable energy projects (15). Smaller numbers were found in household device projects (4) and chemical/industrial process projects (1).

Some of the largest problematic projects included in the report were the Pacajai REDD+ Project in Brazil, the Southern Cardamom REDD+ Project in Cambodia, and the Alkumru Hydroelectric Power Plant in Turkey.

Broader Market Implications
The findings represent a snapshot but point to broader concerns across the VCM. The report notes that 43 of the top 100 projects in 2024 were not rated by major agencies like BeZero, Sylvera, or Renoster – leaving the quality of 34.7 million additional credits unclear. Nine other projects that were rated by these agencies also raised red flags, representing a further 6.2 million potentially problematic credits.

The authors of the report question why such a flawed and risk-laden system continues to play a central role in global climate action strategies. Despite ongoing reforms, they argue that VCM 2.0 appears structurally incapable of delivering credible, permanent emissions reductions at the scale and speed required.

Critical Questions Ahead of COP30
With Brazil set to host COP30 later this year, the findings raise pressing questions about the future of voluntary carbon markets as a tool for climate mitigation. The report urges a re-evaluation of the roles played by registries, verifiers, and investors, calling for accountability and transparency across the entire carbon credit value chain.

“Climate action must not fail. There must be absolute certainty that the solutions posed to solve the most pressing global crisis are guaranteed to work at the scale and in the timeframe needed, and that they align with – rather than further erode – justice,” the report warns. “Should we fail, the consequence will be millions and millions of lives and tens of trillions of dollars, annually.”