Emissions and efficiency of improved woodburning cookstoves

A comparison was made of the thermal efficiency and emissions of the traditional three-stone fire and the "Plancha " improved stove-burning wood. Simultaneous measurements of efficiency and emissions of suspended particles and carbon monoxide were taken in order to incorporate both of these factors into a single standard of performance- missions per standard task. These factors were measured during both a Water Boiling Test (WBT) and a Standardized Cooking Test (SCT). No statistical difference in efficiency between the Plancha and traditional stove was found. The Plancha required more time to perform both of the tests, and this difference was statistically significant (p=0.048) for the WBT. The Plancha emitted 87 % less suspended particles less than 2.5 ~tm in diameter (PM2.5) and 91 % less CO per kJ of useful heat delivered compared to the open fire during the WBT. The relative nvironmental performance ofthe Plancha improved uring the SCT, resulting in a 99 % reduction of total suspended particulate matter (TSP) emissions and a 96% reduction of CO emissions per standardized cooking task. A strong correlation (r 2 = 0.87) was found between the average kitchen concentrations ofCO and PM2.5 during the WBTs, indicating the usefulness of CO measurements as an inexpensive and accurate way of estimating PM2.5 concentrations. 01998 Elsevier Science Lt