Abstract
Ethiopia has declared a national biofuel production and utilization strategy in the GTP to assure energy security and minimize the risks associated with deforestation and GHG emission. The objective of this study was evaluating the utilization of jatropha oil blended with ethanol and kerosene for cookstove utilization.
The study was assessed (a) the effect of temperature and addition of ethanol or kerosene on the viscosity of jatropha oil (b)The thermal efficiency, SFC and CO emissions of ethanol and jatropha oil stoves operated with ethanol- jatropha oil and kerosene - jatropha oil blended fuels respectively. The viscosity data were collected using Brookfield viscometer model DV2T from 20 oc to 100 oc and at 10, 20, 30 and 40 % jatropha blended with ethanol and kerosene fuels. Thermal efficiency, SFC and CO emissions data were collected using Water Boiling Test protocol (WBT version 4.2.2) at 10, 20 and 40 % jatropha oil blended with ethanol and kerosene fuels. The results show that viscosity of jatropha oil was significantly reduced on heating (p<0.01) and on blended with ethanol (p<0.018) and kerosene (p<0.023).The performance test result showed Ethanol and Jatropha oil stoves thermal efficiency was above 50% up to 40% jatropha oil .SFC and CO of the stoves increases as the ratio of the Jatropha oil increases in the blend. The maximum ratio of Jatropha oil blended with Ethanol and Kerosene was 40 % and shows above 50% thermal efficiency while improved biomass cook stoves such as traditional charcoal stoves, Tikikil and Lakech cook stoves has 23, 26 and 38 % thermal efficiencies, respectively .CO emission of jatropha oil stove and ethanol stove up to 40% jatropha oil showed below 36 grams of CO emission to boil 2.5liters of water while improved cookstoves such as Merchaye, Lakech and traditional cookstoves has 66, 79 and 92 grams of CO emission to boil 2.5 liters of water. Since utilization of Jatropha oil up to 40% blended with ethanol or kerosene fuels on ethanol and jatropha oil stoves have higher thermal efficiency and lower CO emission than other improved cook stoves ,it can be used to reduce deforestation and CO emissions over the existing cook stoves, further improvement of the Jatropha oil stove still needed.
Key words: - Viscosity, Thermal efficiency, Blending, specific fuel consumption, emission
