Corporate Climate Solutions

Fuel-Efficient Cookstoves

This report was last updated in November 2020. It may no longer be accurate, both with respect to the evidence it presents and our assessment of the evidence. We may revise this report in the future, depending on our research capacity and research priorities. Questions and comments are welcome.‍

‍

Adoption of fuel-efficient cookstoves can decrease household fuel use and therefore carbon emissions. There are a wide variety of cookstove offsets on the market, using different technologies in different contexts. Although the methodology used to certify these projects ensures that they make a reasonable case for offsetting emissions, it also requires strong assumptions around stove use and changes in cooking behavior. The impact evaluation literature shows highly mixed results. Some randomized control trials (RCTs) show cookstoves having strong effects on fuel usage while others show null effects.

We do not feel comfortable recommending cookstove offsets in general, as the RCT literature shows that the required assumptions are frequently not satisfied. We would recommend offset projects similar to those that have shown strong results in a rigorous evaluation, such as the recent work by Berkouwer and Dean. Given this RCT, we recommend offsets generated by the the manufacturer of the cookstoves studied in that paper, BURN.

‍

Efficient cookstoves result in decreased emissions by decreasing the amount of fuel (generally wood) a household uses for cooking. This causal mechanism is theoretically valid, but in practice, even the introduction of stoves that are mechanically superior will not result in reductions in fuel usage, due to variations in human behavior. Certifiers such as the Gold Standard use a specific methodology to calculate emissions reductions from cookstove projects. We base our assessment off of the Gold Standard methodology, but to the best of our understanding, the methodology of the other certifiers is roughly similar. Their calculation relies on a standard model which takes into account the baseline value of fuel usage, the efficiency of the stove, and pre-determined conversion factors of wood to emissions to calculate emissions reductions. It also includes corrections for some human behavior elements, such as the fraction of households who continue to use the less efficient stoves and the fraction of cooking that continues to be conducted on the old stoves.

Key model parameters, such as whether households are still using the more efficient stoves, need to be continually verified by a third party in order for carbon credits to be issued.

Overall, we have three main concerns with cookstove certification methods:

There is no actual measurement of fuel usage. While this is understandably difficult to measure, it would provide an indication of the magnitude of avoided CO₂. Without this data, we have to rely on strong assumptions about usage of the stove and its efficiency in real-world conditions. Additionally, the offset certifiers assume that energy demand stays constant, even though the stove drastically decreases the price of cooking by reducing fuel needed.
There is no comparison group. Offset certifiers estimate a reduction of fuel usage compared to the households’ fuel use prior to cookstove distribution. Thus, we must make the strong assumption that the level of wood consumption would have stayed constant in absence of the cookstoves. This may not be true if cooking practices are changing over time for other reasons, such as decreasing availability of foraged wood.
Verification data is collected by recipients of offset funds. Verification surveys in the field are contracted by the project developers. They have a strong incentive to show that stoves are being used.

Given that certification methodologies rely on a number of questionable assumptions, we next ask whether these are validated in the academic literature. Fortunately, a number of high-quality RCTs on improved cooking technology have been conducted in a number of contexts. RCTs are the gold standard in determining causality. If these studies generally find that stove usage remains high and wood usage decreases, they make a strong case for cookstoves meaningfully reducing emissions.

Unfortunately, the results of these studies are mixed. Certainly, some show positive results. For instance, Bensch and Peters (2015) conduct an RCT of improved cookstoves in Senegal and indeed find large decreases in firewood usage. But they also find that 27% of meals are still cooked on traditional stoves in the treatment group a year after distribution, which is higher than the assumptions we see in many offset projects. Berkouwer and Dean (2019) find that improved cookstoves in Kenya lead to reductions in fuel expenditure by 40%, close to the manufacturer’s claims of 50% reduction, and that these effects persist for 18 months after the cookstoves’ adoption. On the other hand, Hanna et al (2016) find no change in greenhouse gas (GHG) emissions from a cookstove project in India, primarily due to dis-adoption of the stoves. Aung et al (2013) find no change in fuel usage for a cookstove project that received emissions credits in India. Beltramo and Levine (2013) also find no effect of an improved cookstove on fuel usage in Senegal.

Due to the strong assumptions that must be made in the certification process and the mixed results in the RCT literature, we do not feel like we can confidently recommend cookstove offset projects unless causality has been validated with a high-quality impact evaluation.

‍

Fuel-Efficient Cookstoves

Cookstoves as a Carbon Offset

Mechanism

Causality

Project-Level Additionality

Marginal additionality

Permanence

Co-Benefits

Assessment of Cookstove Projects

References

Explore More Climate Giving Research

Support Our Work

Giving Green Fund

Top Climate Nonprofits

Support Our Work