Systematic assessment of the achieved emission reductions of carbon crediting projects

Benedict S Probst; Malte Toetzke; Andreas Kontoleon; Laura Díaz Anadón; Jan C Minx; Barbara K Haya; Lambert Schneider; Philipp A Trotter; Thales A P West; Annelise Gill-Wiehl; Volker H Hoffmann

doi:10.1038/s41467-024-53645-z

Systematic assessment of the achieved emission reductions of carbon crediting projects

Nat Commun. 2024 Nov 14;15(1):9562. doi: 10.1038/s41467-024-53645-z.

Authors

Benedict S Probst^{1

2

3}, Malte Toetzke^{4

5}, Andreas Kontoleon⁶, Laura Díaz Anadón^{6

7}, Jan C Minx^{8

9}, Barbara K Haya¹⁰, Lambert Schneider¹¹, Philipp A Trotter^{12

13}, Thales A P West^{6

14}, Annelise Gill-Wiehl¹⁵, Volker H Hoffmann¹⁶

Affiliations

¹ Net Zero Lab, Max Planck Institute for Innovation and Competition, Munich, Germany. [email protected].
² Group for Sustainability and Technology, ETH Zurich, Zurich, Switzerland. [email protected].
³ Department of Land Economy, Centre for Environment, Energy, and Natural Resource Governance, University of Cambridge, Cambridge, UK. [email protected].
⁴ Net Zero Lab, Max Planck Institute for Innovation and Competition, Munich, Germany.
⁵ Public Policy for the Green Transition, Technical University of Munich, Munich, Germany.
⁶ Department of Land Economy, Centre for Environment, Energy, and Natural Resource Governance, University of Cambridge, Cambridge, UK.
⁷ Harvard Kennedy School, Harvard University, Boston, MA, USA.
⁸ Mercator Research Institute on Global Commons and Climate Change, Berlin, Germany.
⁹ Priestley International Centre for Climate, School of Earth and Environment, Leeds, UK.
¹⁰ Goldman School of Public Policy, University of California, Berkeley, CA, USA.
¹¹ Öko-Institut, Berlin, Germany.
¹² Schumpeter School of Business and Economics, University of Wuppertal, Wuppertal, Germany.
¹³ Smith School of Enterprise and the Environment, University of Oxford, Oxford, UK.
¹⁴ Institute for Environmental Studies (IVM), Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
¹⁵ Energy & Resources Group, University of California, Berkeley, CA, USA.
¹⁶ Group for Sustainability and Technology, ETH Zurich, Zurich, Switzerland.

Abstract

Carbon markets play an important role in firms' and governments' climate strategies. Carbon crediting mechanisms allow project developers to earn carbon credits through mitigation projects. Several studies have raised concerns about environmental integrity, though a systematic evaluation is missing. We synthesized studies relying on experimental or rigorous observational methods, covering 14 studies on 2346 carbon mitigation projects and 51 studies investigating similar field interventions implemented without issuing carbon credits. The analysis covers one-fifth of the credit volume issued to date, almost 1 billion tons of CO₂e. We estimate that less than 16% of the carbon credits issued to the investigated projects constitute real emission reductions, with 11% for cookstoves, 16% for SF₆ destruction, 25% for avoided deforestation, 68% for HFC-23 abatement, and no statistically significant emission reductions from wind power and improved forest management projects. Carbon crediting mechanisms need to be reformed fundamentally to meaningfully contribute to climate change mitigation.