Association for Public Policy Analysis & Management

Globally, three billion people rely on solid fuels such as wood to satisfy their daily heating and cooking needs. These fuels, burned in traditional stoves with limited ventilation, release harmful levels of household air pollution (HAP). This HAP ranks as the third greatest risk factor leading to global premature mortality (WHO 2012). Improved cookstoves, or ICS (e.g., gas, electric and efficient biomass-burning stoves) have received widespread international attention as a means to reduce wood consumption, time spent cooking and gathering fuels, emissions of short-lived climate forcers, as well as personal exposure to such HAP.

Despite these seemingly large benefits, ICS dissemination programs have faced challenges of uptake and sustained use. Even when adopted, most ICS are rarely used exclusively - rather, these stoves are used for specific cooking and heating tasks alongside traditional stoves/fuels. The challenges of low adoption and mixed use combined with the complications of conducting air pollution measurements in remote locations has resulted in very few rigorous field evaluations of air pollution impacts from clean stove use. As momentum builds towards promoting new technologies to reduce HAP exposure, quantitative evaluations of the emissions from use of these stoves in realistic field settings is critical. Such evaluation must pay attention to stove use by poor households under real world conditions, and therefore account for human behavioral responses to these new technologies.

We leverage a recently completed RCT that sold electric and biomass ICS to households in Uttarakhand, India, and select 200 total households from 38 hamlets. Using survey data collected following the sales campaign, we selected three quarters of these from a group found to be using improved stoves or fuels for some heating and cooking activities, while the remaining 50 only used traditional stoves. Moreover, the 150 ICS users were selected to represent a broad distribution of levels of actual ICS use, defined as the proportion of total cooking and heating hours conducted with an electric, gas, or efficient biomass-burning stove.  The proportion of hours ICS is used is significantly associated with increased education, female headed-households, and electricity availability.

We evaluate the impact of ICS use on household and personal air pollution using samples of particulate matter with a diameter of 2.5 micrometers or less (PM2.5). PM2.5 has adverse health impacts when inhaled, particularly acute respiratory infections and chronic obstructive pulmonary disease, and are naturally emitted during the cooking process.  Filter samples of PM2.5 were collected over 24 hours in all 200 households using a sampling unit suspended near the stove, and also a waist back worn by each primary cook to assess personal exposure. Electronic stove use monitors were placed on all stoves in the household (traditional and ICS) to objectively verify use over 24 hours. In addition, we weighed the wood burned in all households for heating and cooking.

This evaluation of the impacts of ICS use on household and personal air pollution provides important empirical evidence on the potential of these new technologies for reducing exposure.