Energy and exergy efficiencies of four biomass cookstoves using wood chips

Abstract

With the growing need for comprehensive analysis of energy conversion systems for performance evaluation and improvement, this study investigates the energy and exergy performance of four biomass cookstoves using wood chips as fuel source. The cookstoves evaluated include the three-stone fire, charcoal stove, modified charcoal stove, and top-lit updraft (TLUD) cookstove. The performance of the cookstoves was carried out following the standard cookstove testing protocol of water boiling test in cold and hot start conditions. Relevant parameters were measured at five-minute interval until the water reached the boiling temperature of 100 °C; the test was replicated four times for each stove and the mean value reported. The result of the study revealed that energy efficiency of the cookstoves was higher than the exergy efficiency both in the cold and hot start. The efficiencies increased steadily with time until the water reached 100 °C boiling temperature. The energy, and exergy efficiency in the cold and hot start condition of the cookstoves appear similar with no obvious difference; that is, the performance of the cookstoves appear the same irrespective of whether the stove is used in the cold or hot start condition. The TLUD cookstove offered better energy and exergy efficiencies compared to other cookstoves investigated.

Keywords:

• biomass fuel
• cookstoves
• energy analysis
• exergy analysis
• water boiling test