ACE one cook stove

Abstract

The study was conducted to evaluate the performance of ACE One cook stove which is manufactured by African Clean Energy (ACE) in Lesotho by assessing the performance of different solid biomass fuels within the stove. Pellets, pine wood, corn cobs and cow dung provided by ACE were used in this study where cooking time, energy consumption, heat transfer, combustion temperature and particulate matter emissions were assessed. The heating values were determined using Proximate Analysis, the values ranged from 13.43 MJ/kg for cow dung to 17.65 MJ/kg for corn cobs. Measurement of air pollutants were performed using mobile air quality monitor and combustion temperature measurements were performed using infrared thermometer. The temperature was measured for each fuel and the highest temperature was found when using wood, about 460 °C, followed by corn cobs with 370 °C, pellets with 340 °C and cow dung with 290 °C. However, the pellets had the most sustained heat compared to other fuels. Using wood and corn cobs transferred heat faster due to their big flame and raised the temperature of the water quickly. When using wood, water in a pot gained 610 kJ in 9 minutes, with corn cobs, pellets and cow dung, energy gained was 410 kJ, 350 kJ and 240 kJ respectively. Water Boiling Tests (WTB) results showed that the use of cow dung required much more fuel and an extended cooking time compared to other fuels. The second WBT using a different mass to test refuelling showed that refuelling slowed the cooking process. When burning the fuels in a closed room, the PM2.5 emissions for all the fuels were above 425 μg/m3, which was considered as hazardous level. Cow dung emitted more particles than other fuels during combustion which lasted longer in a room. The pellets showed the lowest emissions of them all in both open and closed room. In a closed room, the highest value for the pellets was 800 μg/m3 while other fuels had reached 999.9 μg/m3. The values obtained when burning the fuels in an open room had shown a significant decrease in emissions, 60.3 μg/m3 for pellets, 144.7 μg/m3 for wood, 234.2 μg/m3 for corn cobs and 612.4 μg/m3. The study further assessed the performance of the charging system that comes along with the stove. The power dissipated by the solar panel in this study was less than its rated power. The highest value from 4 experiments done one different days was 8.57 W. Time taken to charge the stove with a wall charger was shorter than using a solar panel. Using the battery of the stove to charge a cell phone has shown high power usage but using it for powering LED lamp has shown to be discharging the battery at a very slow rate.