A new investigation has raised serious concerns over the credibility of many large-scale carbon offsetting projects, revealing that their actual climate impact in 2024 may have fallen far short of claims.
According to research published this week by advocacy group Corporate Accountability, 43 high-profile projects accounted for 47.7 million tonnes of carbon credited as avoided or removed—representing nearly a quarter of the global voluntary carbon market (VCM) total for the year. However, the analysis found that eight in ten of the world’s 100 largest carbon offset projects were “problematic”, either due to inflated emissions claims or social and environmental harm.
The study highlights systemic flaws in the voluntary market, including widespread over-crediting and the delivery of negligible or no additional climate benefits in many cases. Nearly one-quarter of the projects examined reportedly failed to deliver new emissions reductions, and 14% were said to have underperformed.
Forestry and land use projects were most frequently flagged, but concerns were also identified in renewable energy, low-carbon household technology, and industrial site offsets. Notably, over 90% of the problematic projects were located in the Global South.
Corporate Accountability argues that the findings demonstrate that current efforts to reform the voluntary carbon market are inadequate. The group is calling on businesses to redirect carbon credit investments towards proven climate solutions and urging policymakers to accelerate regulatory oversight and introduce stronger accountability mechanisms.
In response to growing criticism, the UK Government reiterated in 2024 its support for carbon and nature credits as part of net-zero strategies, while acknowledging concerns about market integrity. It is currently consulting on principles to guide credit buyers, with a focus on transparency and quality. Similar initiatives are underway in countries including Kenya, Singapore, and Japan.
Despite the credibility issues, analysts at Wood Mackenzie remain optimistic about the long-term future of the voluntary carbon market. They forecast growth from fewer than 500 million tonnes of CO₂-equivalent credits in 2025 to as much as 3 billion tonnes by 2050, driven by tightening regulations and increasing demand from hard-to-abate sectors such as aviation.
Prices are also expected to climb. From current averages around $10 per tonne, Wood Mackenzie projects a fivefold increase by mid-century, contingent on efforts to improve offset quality.
“The carbon offset market is entering a decisive phase,” said Peter Albin, senior research analyst at Wood Mackenzie. “While the demand-led push for higher quality offsets may temper near-term growth, it’s laying crucial groundwork for long-term market expansion.”
