akar.earthOvercrediting: Definition
What is overcrediting? When carbon projects issue more credits than real climate impact, the main causes in REDD+ and ARR, and how to avoid it.
Overcrediting is when a carbon project receives more credits than the emission reductions or removals it actually achieved. Each excess credit represents a tonne that was never avoided or removed, so buyers relying on it overstate their climate impact.
Why it matters
Overcrediting is the main integrity criticism of the voluntary carbon market. Studies and media reports on REDD+ baselines damaged trust and prices across nature-based credits. Rating agencies, the ICVCM and buyers now focus on it. Quality matters for price: BeZero ratings show prices rising about 40% per rating band.
Main causes
- Inflated baselines: projecting more deforestation or less growth than would really happen. See baseline setting.
- Weak additionality: crediting activities that would have happened anyway.
- Uncounted leakage: emissions shifting outside the project.
- Measurement error: biomass models or sampling that overestimate stocks without an uncertainty deduction.
- Missed reversals: fires or clearing after issuance not reported.
How it is reduced
Newer methodologies use dynamic or jurisdictional baselines that track what actually happens in control areas. Verra’s VM0047 uses a dynamic performance benchmark from control plots, and VM0048 allocates REDD+ baselines from jurisdictional data. Conservative defaults, field calibration and independent verification also help.
Indonesia and Southeast Asia angle
Indonesia has a large stock of REDD+ credits from older methodologies. BeZero’s 11 rated ex-post Indonesian projects average ‘A’, better than the common ‘B’ elsewhere, but buyers still examine each baseline. New projects should be designed with current methods from the start. Read the REDD+ baseline controversy and see how credit ratings agencies assess it.
Buyers can protect themselves by checking the baseline method, comparing claimed deforestation rates with independent data, reading rating summaries and preferring recent methodology versions. Developers benefit too: projects with conservative, transparent accounting tend to hold their value when scrutiny rises.
Common mistakes
- Choosing the most favourable reference region.
- Using ex-ante growth curves as if they were measured.
- Ignoring buffer and uncertainty rules.
Frequently asked questions
What causes overcrediting in REDD+?
Mostly inflated baselines that assume more deforestation than would actually have happened. Leakage that is not fully counted and weak monitoring add to it.
How are standards responding?
Through new methodologies with jurisdictional or dynamic baselines, such as Verra's VM0048 for REDD+ and VM0047's dynamic performance benchmark for ARR, plus ICVCM assessments.