Experimental Characteristics of Bioethanol-Gasoline Blended Fuels: Analysis of Air-Fuel Ratio, Exhaust Emissions, and Fuel Consumption in Spark Ignition Engines

The development of alternative fuels based on bioethanol has been encouraged by the current energy crisis and the increase in motor vehicle emissions. The performance characteristics of Pertamax–bioethanol fuel blends (E0, E20, E40, E60, and E80) in Spark Ignition Engines without modification are examined in this study, with an emphasis on fuel consumption, exhaust emissions, and air fuel ratio. A four-gas analyzer and a flow meter were used to conduct the experiments throughout an engine speed range of 1500–7500 rpm. The results show that a leaner mixture can be produced by increasing the concentration of bioethanol, as seen by higher AFR and lambda values. The E80 blend significantly decreased HC emissions by 81% at 1500 rpm, going from 354 PPM to 66 PPM. The E20 blend reduced CO emissions by up to 70% at higher engine speeds. CO2 emission increased by 5–10% for all bioethanol mixes, suggesting more thorough burning. Fuel usage increased in direct proportion to the quantity of bioethanol; at 7500 rpm, the E80 blend used 24.2% more fuel than E0. The E20 and E40 mixes provide the best mix of fuel efficiency and emission reduction for driving in cities. At low to medium engine speeds, however, the E60 and E80 perform better. Overall, the findings show that bioethanol blends up to E40 may be accommodated by normal electronic fuel injection systems with just little modifications, supporting the wider use of alternative fuels in standard Indonesian vehicles.