Cleaner Cooking: Exploring Tools to Measure and Understand the Long-term Adoption and Environmental Significance of Cookstoves in India

About 40% of the world’s population, or roughly 3 billion people, rely on solid biomass fuels like coal, wood, dung, and crop residues to cook and meet their household energy needs. This outdated energy system has severe social, health, and environmental implications. Women are disproportionately affected as they predominantly bear the burden of cooking and collecting fuelwood, which exacerbates the “time poverty” trap that restricts them from participating in economic and educational activities. Exposure to indoor solid fuel combustion, also known as household air pollution, is responsible for 3-4 million premature deaths per year and is a leading risk factor for chronic obstructive pulmonary disease, childhood pneumonia, stroke, ischemic heart disease, and lung cancer. Solid-fuel cooking contributes to 16% of global ambient air pollution, emitting CO2 and other climate-forcing pollutants like carbon monoxide, black carbon, and methane./nTo tackle the issue of solid-fuel cooking on a global scale, initiatives have been launched to introduce energy-efficient cookstoves known as “improved” or “clean” cookstoves. These cookstoves can significantly reduce fuel use, emissions, and cooking time compared to open fires or rudimentary cookstoves. They are considered a cost-effective climate mitigation strategy, with the potential to reduce emissions by 1 Gigatonne CO2e per year if implemented globally. Nevertheless, for improved cookstoves to have any tangible health benefits, they must attain high levels of efficiency. The reduced burden on women from less fuelwood collection time and labor, as well as shorter cooking times, should not be disregarded, but households must first adopt the improved cookstoves for any benefits to be achieved./nImproved cookstoves programs have largely failed to achieve their promised advantages due to low levels of sustained adoption. Often, cookstoves have inadequate performance in the field compared to lab settings and fail to meet users’ needs. Moreover, the widespread use of unreliable methods, such as surveys, to measure the adoption and impact of the cookstoves has hindered the cookstoves sector from advancing. Surveys can be unreliable for measuring quantitative data, as there are different biases associated with interviews, and studies have shown that households tend to over-report their usage. Existing methodologies used to verify carbon emission reductions from cookstoves projects do not require usage monitoring and allow for the use of default cookstove emission factors, resulting in inaccurate estimations. Temperature dataloggers or “stove use monitors” have emerged as a reliable, objective method to measure users’ actual usage and provide more granularity. Despite this, surveys are still widely used to measure usage and thus, projects may be failing to capture dis-adoption, which is still poorly understood. More research is needed to develop measurement methods that are accurate, feasible, and affordable./nThe success of improved cookstoves projects depends on designing with and for users, using reliable long-term methods to measure impact and usage, and understanding the reasons for usage or lack of usage. This dissertation aims to achieve these goals by adapting a successful, cost-effective cookstove from Africa to India, identifying motivations and barriers to adoption through case studies in rural Maharashtra, where fuelwood is widely used for cooking, and improving methods for estimating the carbon significance of cookstoves projects. Chapter 1 provides background on the health and climate effects of solid-fuel cooking, as well as current solutions and areas where more research is needed. In Chapter 2, I describe thedesign process of adapting a cost-effective, successful cookstove, the Berkeley-Darfur Stove (BDS) from Africa to rural Maharashtra. While some issues could not be addressed without a complete re-design, women who participated in the design process expressed interest in purchasing the modified BDS, called the Berkeley-India Stove (BIS). Chapter 3 then compares survey-reported usage and sensor-recorded cooking events (durations of use) of the BIS in two monitoring studies, in rural Maharashtra, that occurred between February 2019 and March 2021. The first was a free trial of the BIS, and the second involved households that purchased the BIS. We found that over-reporting usage was common in both studies and surveys failed to detect the long-term declining trend in usage in the second study. In Chapter 4, we analyze the sensor data of the second study. We found that about 43% of households had an overall decreasing trend in usage, average daily usage stabilized around 95 days and households used the stove intermittently, with some demonstrating intervals of nearly 3 months of no usage, on average, between periods of use. Finally, in Chapter 5, we present the results of comparing the performance and emissions in lab-based experiments of the BIS and the baseline cookstove, the mud chulha, which has existed in South Asia for millennia. We found that the BIS used 43% less fuelwood and emitted 25% less PM2.5 compared to the mud chulha for the same cookstove task. We also present methods to use the temperature dataloggers—previously used to measure usage—for estimating the BIS’ fuelwood burn rate and CO2 emission rate./nIn summary, this research presents case studies and method analyses that highlight the importance of incorporating user-centered design techniques and sensor data in cookstove interventions. Using reliable methods to measure the impact of cookstoves’ projects is necessary for the development of the cookstoves sector and addressing the negative effects of solid-fuel cooking globally. Moreover, the lessons learned from these studies can also extend to technology intervention projects more broadly.

Advisor: Gadgil, Ashok