Cooking the books: Pervasive over-crediting from cookstoves offset methodologies

Abstract Carbon offsets from improved cookstove projects could advance Sustainable Development Goals 13 (climate), 7 (energy), 5 (gender), and 3 (health). To legitimately "offset" emissions, methodologies must accurately or conservatively quantify climate impact. We conduct the first comprehensive, quantitative over/under crediting analysis of five cookstove methodologies, comparing them against published literature and our own analysis. We find misalignment, in order of importance, with: fraction of non-renewable biomass, fuel consumption, stove adoption, usage, and stacking, emission factors, rebound, and firewood-charcoal conversion factor. Additionality and leakage require more research. We estimate that our project sample, on average, is over-credited by 6.3 times. Gold Standard’s Metered and Measured methodology, which directly monitors fuel use, is most aligned with our estimates (only 1.3 times over-credited) and is best suited for fuel switching projects which provide the most abatement potential and health benefit. We provide specific recommendations for aligning all methodologies with current science.