In Short : The statement “Cookstove emissions are underestimated by a factor of 10” indicates that the emissions from traditional cooking stoves, often used in many households, may be ten times higher than previously estimated. This underscores the importance of accurately assessing and addressing the environmental impact of common practices, such as cooking, to better understand and mitigate their contribution to air pollution and climate change.
In Detail : The global carbon market’s fastest-growing offset, which promotes the distribution of efficient cookstoves in developing nations to decrease greenhouse gas emissions, significantly overstates the stoves’ carbon savings – by a tenfold margin, a recent investigation has revealed.
Confidence in the carbon market
This discrepancy poses a significant challenge to combating climate change by enabling companies to claim climate goals and market “carbon neutral” products without actual reductions in greenhouse gas emissions. It also erodes confidence in the carbon market, thereby affecting the market’s capability to sustainably fund efficient stoves.
Focus of the research
The study, published in Nature Sustainability, represents the first thorough, quantitative evaluation of any offset project type. Researchers at the University of California, Berkeley scrutinized five methodologies used to assess cookstove emission reductions against published studies and independent analyses.
Clean cooking and social justice
Daniel Kammen, the James and Katherine Lau Distinguished Professor of Sustainability at UC Berkeley, emphasized the critical link between clean cooking and global strategies for social justice and climate, noting the significant attention the pre-published study has garnered.
“Clean cooking now figures very centrally on national decarbonization and sustainable development goal strategies, global funding cycles, and the political agenda of national leaders,” said Kammen. “Integrating the science, human rights, and economics of clean cooking is now critically linked to both social justice and climate strategies around the planet.”
Carbon offset credits
The popularity of cookstove offsets stems from the global reliance on solid fuels or kerosene by approximately 2.4 billion people, contributing to millions of premature deaths and around 2% of global greenhouse gas emissions annually. In the first ten months of 2023, efficient cookstoves constituted the voluntary carbon market’s fastest-growing project type and the second-largest share of issued credits.
Annelise Gill-Wiehl, a UC Berkeley Ph.D. candidate and the study’s first author, highlighted the potential of accurately estimated carbon offsets to support the distribution of efficient stoves, reducing fuel costs and potentially saving lives.
“Estimated correctly, carbon offsets have the potential to support the free or subsidized distribution of efficient stoves that reduce time spent collecting firewood or the cost of purchasing fuel,” she said.
Substantial over-crediting
However, the study revealed substantial over-crediting, suggesting that many projects exaggerate stove usage and underestimate the continued use of traditional stoves, among other issues.
The Berkeley team’s recommendations for aligning cookstove methodologies with current science include prioritizing stoves that meet World Health Organization health standards, as most market stoves do not. They developed a method for assessing offset quality, which can guide buyers, developers, and regulators towards high-quality credits that genuinely benefit health and climate goals.
Key findings
In the sample covering 40% of cookstove credits, the team found that cookstoves were over-credited by a factor of 9.2 times. Across all cookstove offset credits from the studied methodologies, cookstoves were over-credited by approximately 10.6 times.
The Gold Standard’s Metered methodology, which directly monitors fuel use and credits the cleanest stoves, was found to be the most aligned with the study’s estimates, overvalued by only a factor of 1.5. This methodology shows the greatest potential for emissions abatement and health benefits.
This investigation not only documents quality issues in the offset market but also provides actionable recommendations for trading in quality credits that align with Sustainable Development Goal progress, offering a paradigm shift towards clean fuels and stoves that can significantly support health and climate benefits.