Saving time and reducing smoke: A sensor-based performance assessment of a forced-draft “Jet-Flame” cooking system in Malawi

The time, health, and climate impacts associated with reliance on biomass fuels for cooking are significant at the global scale, and particularly harmful to women. To help mitigate these impacts, the Jet-Flame forced draft cookstove retrofit accessory was designed to apply jets of high-momentum air into the fuelbed of existing cooking stoves to improve combustion efficiency and cooking speed. Paired with a rocket cookstove and solar home power kit and light, the device usage and resulting changes in cooking time and kitchen PM_2.5 concentrations were measured in 40 households in Malawi across four study phases using an integrated suite of sensors. Results revealed cooking time across all households was reduced by 29 % upon introduction of the Jet-Flame. Households that used the Jet-Flame more than 80 % of the time in a rocket stove showed an average reduction of 64 % in kitchen PM_2.5 concentration relative to the baseline. Battery power consumption data showed the daily power consumed by the Jet-Flame(s) (200 mAh) was about 10 % of the power consumed relative to the lights and phone chargers (1000 mAh each), suggesting a low power draw by the Jet-Flame and remaining battery capacity available for other uses that are valued by these unelectrified households. Finally, the estimates of carbon dioxide equivalent (CO_2e) emissions reductions earned by implementing the stove and Jet-Flame kit, including fuel savings and reductions in black carbon fraction from 38 to 19 % measured in the laboratory, indicated a reduction in 5.7 tons of CO_2e per stove year from baseline at a fuel harvest non-renewability of 26 % when using the stove and Jet-Flame together. These findings indicate this suite of technologies may potentially help to affordably address global goals for climate, health, and gender equity; especially if supported by carbon and co-benefit financing.