Fuel efficiency and air pollutant concentrations of wood-burning improved cookstoves in Malawi: Implications for scaling-up cookstove programs

Abstract

National governments and other key stakeholders in developing countries are grappling with how to reduce household air pollution (HAP) resulting from cooking with solid fuels using traditional cooking technologies. Recent studies have shown that improved cookstoves may offer reductions in fuel use and harmful emissions of carbon monoxide (CO) and fine particulate matter (PM2.5), yet there is little quantitative evidence collected in a “real-world” setting showing how improved stoves perform directly compared to traditional cooking technologies. Our simulated kitchen study takes place in a semi-controlled, “real-world” setting in Malawi and was designed to quantify the fuel efficiency improvements and air pollutant concentration reductions capabilities of two improved stoves currently marketed in the country. In this study, we perform a Water Boiling Test (WBT) to compare the air pollutant concentrations (CO and PM2.5) and fuel efficiency of the traditional three-stone fire stove and two improved cookstoves: a locally produced clay stove known as the Chitetezo Mbaula (CM) and a Philips gasifying stove. We find that the Chitetezo Mbaula uses 53% of the fuel used by the traditional three-stone fire, and produces 59% of CO, and 50% of PM2.5 of the three-stone fire. The Philips gasifying stove uses 31% of the fuel, and produces 38% of CO, and 22% of PM2.5 of the traditional three-stone fire. We consider the potential for the wide-scale adoption of each of these technologies given their relative costs and conclude that lower-cost, intermediate quality cookstoves are an important and realistic first step toward reducing household air pollution.

Systems Science Approaches for Global Environmental Health Research: Enhancing Intervention Design and Implementation for Household Air Pollution (HAP) and Water, Sanitation, and Hygiene (WASH) Programs

“…A well-understood limitation of previous household energy programs was that air pollution emissions from improved cookstoves in community settings greatly exceeded what was expected based on laboratory testing (Coffey et al 2017;Eilenberg et al 2018). Clean fuel interventions with liquefied petroleum gas (LPG), electric induction, ethanol, biogas, and pellet-fueled gasifier stoves have consistently outperformed traditional and improved solid-fuel stoves in both laboratory and field studies (Champion and Grieshop 2019;Jagger et al 2017;Wathore et al 2017) and are the most likely to achieve the desired air quality and health benefits.…”

“…As described in the preceding two sections, there are numerous examples of projects that have underdelivered because of shortcomings of the technology. Many improved biomass stoves do not deliver the air pollution reductions required to greatly minimize adverse health impacts, although they do reduce fuel use and may provide some reduction in air pollution (Jagger et al 2017). Improved water supplies do not necessarily provide water that is safe at the point of collection (Bain et al 2014), in part because most household water treatment options fail to cover the full array of waterborne pathogens or fail to keep water safe after it is treated (Shaheed et al 2014).…”

“…2018 ). Clean fuel interventions with liquefied petroleum gas (LPG), electric induction, ethanol, biogas, and pellet-fueled gasifier stoves have consistently outperformed traditional and improved solid-fuel stoves in both laboratory and field studies ( Champion and Grieshop 2019 ; Jagger et al. 2017 ; Wathore et al.…”

“…As described in the preceding two sections, there are numerous examples of projects that have underdelivered because of shortcomings of the technology. Many improved biomass stoves do not deliver the air pollution reductions required to greatly minimize adverse health impacts, although they do reduce fuel use and may provide some reduction in air pollution ( Jagger et al. 2017 ).…”

Exploratory study of Polycyclic Aromatic Hydrocarbon (PAH) contributions to household air pollution arising from improved cookstove use in rural Malawi

“…The above is indicative of the Malawian climate in which ICS research and development finds itself. Cookstoves are foremost in Malawian policy agenda, cutting across energy, environment, health, and gender sectors (Jagger et al, 2017). ICS implementaion is supported by a growing diversity of cookstove research in Malawi, including: Wathore et al 2017…”