Comparative evaluation of thermal and emission performances for improved commercial coal-fired stoves in China

The extensive use of traditional cooking stoves to meet daily cooking and heating requirements has highlighted the serious problem of indoor and outdoor air pollution. This study evaluates seven improved coal-fired space-heating and cooking stoves and compares them with a widely used stove of an older design, selected as a baseline reference. The seven stoves were selected from a range of candidate improved stoves submitted by manufacturers for testing as part of the air quality improvement in the Hebei Clean Air Project, Hebei Province, China. Stove performance was evaluated when burning raw coal and coal briquettes during the high and low power stages respectively. All seven improved cooking stoves surpassed the baseline stove in combined heating and cooking thermal and emission performance. Among the improved cooking stoves, Model 2-TL was found to have the highest average thermal efficiency, 87.2 ± 0.5%, when burning coal briquettes at high and low power. The lowest emission of PM_2.5 was 0.94 ± 0.5 mg MJ_NET ^-1, CO 0.55 ± 0.28 g MJ_NET ^-1, and CO/CO₂ 1.1 ± 0.6%, respectively. It is concluded that the use of these improved heating and cooking stoves should be promoted for daily cooking and heating requirements. This strategy will not only save fuel to the benefit of the household, but widespread adoption could contribute to significant reductions of CO and PM_2.5 emissions in Hebei Province.