EMISSIONS AND EFFICIENCY OF IMPROVED WOODBURNING COOKSTOVES IN HIGHLAND GUATEMALA

A comparison was made of the thermal efficiency and emissions of the t raditional three-stone fire and the ''Plancha'' improved stove-burning wood. Simultaneous measurements of efficiency and emissions of suspen ded particles and carbon monoxide were taken in order to incorporate b oth of these factors into a single standard of performance - emissions per standard task. These factors were measured during both a Water Bo iling Test (WBT) and a Standardized Cooking Test (SCT). No statistical difference in efficiency between the Plancha and traditional stove wa s found. The Plancha required more time to perform both of the tests, and this difference was Statistically significant (p=0.048) for the WE T. The Plancha emitted 87% less suspended particles less than 2.5 mu m in diameter (PM2.5) and 91% less CO per kJ of useful heat delivered c ompared to the open fire during the WET. The relative environmental pe rformance of the Plancha improved during the SCT, resulting in a 99% r eduction of total suspended particulate matter (TSP) emissions and a 9 6% reduction of CO emissions per standardized cooking task. A strong c orrelation (r(2) = 0.87) was found between the average kitchen concent rations of CO and PM2.5 during the WBTs, indicating the usefulness of CO measurements as an inexpensive and accurate way of estimating PM2.5 concentrations. (C) 1998 Elsevier Science Ltd.