This dissertation combines three empirical studies aimed at addressing one of the developing world’s leading causes of death – exposure to household air pollution from using biomass as a cooking fuel –which is responsible for millions of premature deaths annually and contributes to global climate change. The first study tests the effects of a soft commitment device on eliminating biomass use among households in India who have access to a clean fuel, LPG. The second and third studies explore reducing biomass use through a fuel-efficient biomass cookstove among a population in Uganda who does not have access to clean fuels. The second study tests the effects of selling a fuel-efficient cookstove (at the market price) on biomass use. The third study focuses on the methodology behind measuring stove use by comparing four methods of measurement.
The first chapter explores how a commitment mechanism may help households who use a mix of biomass and clean cooking fuels to fully transition to clean fuels. Most Indian households now own an LPG stove and one LPG cylinder. However, many households continue to regularly use indoor biomass-fueled mud stoves (i.e., chulhas) alongside LPG. Focusing on this population in rural Maharashtra, India, this study tests the effects of conditioning a sales offer for a spare LPG cylinder on a soft commitment device requiring initially disabling indoor chulhas. We find that almost all relevant households (>98%) were willing to accept the commitment device. Indoor chulha use decreased by 90% when the sales offer included the commitment device, compared to a 23% decrease without it. If the effects are persistent, this intervention may be one of the most cost-effective means to save lives among tens of millions of Indian households. Using WHO-CHOICE criteria and conservative assumptions, this intervention generates benefits roughly 20 times larger than the costs.
The second chapter, co-authored with Theresa Beltramo, Garrick Blalock, David I. Levine, and Andrew M. Simons, is among the first studies to examine the effects of a fuel-efficient biomass cookstove while selling the stove at market prices. After introducing a fuel-efficient cookstove, fuelwood use and household air particulates declined by 12% and by smaller percentages after adjusting for observer-induced bias, or the Hawthorne effect. These reductions were less than laboratory predictions and fell well short of World Health Organization pollution targets. Even when introducing a second stove, most households continued to use their traditional stoves for most cooking. While any reduction in fuel use and particulate matter was likely beneficial, fuel-efficient biomass cookstoves such as the one used in this study will not be adequate to reach safe levels of household air pollution. Thus, policies that assist consumers to shift to safe fuels such as gas or electricity—particularly when coupled with policies to disable smoky indoor stoves—should take on increased importance.
The third chapter, co-authored with Theresa Beltramo, Garrick Blalock, Juliet Kyayesimira, David I. Levine, and Andrew M. Simons, compares four methods of measuring stove use: time spent cooking (measured by heat sensors on stoves), number of people cooked for (self-reported), fuel weight used (measured by a scale), and particulate matter concentrations (measured by a monitor). We find statistically significant positive correlations between five out of six of these pairs of measures. While the correlations are positive, the explanatory power of each measure for another is weak. The weak correlations emphasize the importance of using multiple measures to track changes in stove use for both researchers and carbon auditors.
