Utilization of higher ethanol blends, 20% ethanol in gasoline (E20), as an alternate fuel can provide apparent benefits like higher octane number leading to improved anti-knocking properties, higher oxygen content resulting in complete combustion. Apart from technical benefits, use of ethanol blends offer certain widespread socioeconomic benefits including option of renewable source of energy, value addition to agriculture feedstock resulting in increase in farm income, creation of more jobs in rural sector and creating job at local levels. Use of higher blends of ethanol can reduce dependence on foreign crude leading to substantial savings in cost of petroleum import.
The impact of higher Gasoline-Ethanol blend (E20), on the fuel system components of gasoline vehicles must be known for assessment of whether the fuel system will be able to perform as intended for the complete design life of the system. Similarly, emission characteristics with use of such alternate fuels must also be evaluated to confirm its suitability before using it.
A comprehensive exercise was conducted for evaluation E20 fuel for its potential as an alternate transportation fuel. Laboratory immersion study on typical metals & non-metals used in the fuel system components of 4-wheelers & 2-wheelers was conducted for evaluation of change in properties, before and after immersion, like weight, volume, tensile strength, elongation, hardness and impact strengths of six elastomers and 4 plastics, and corrosion rate of eight metals. Statistical evaluation of the test results of properties, for elastomers and plastics, was conducted and majority of the results were found to be statistically significant.
Field trials were conducted on six 4-wheelers (old and new) through running-in, with both E20 and commercial gasoline, on roads representing various conditions and driving patterns including city, highway, expressway, hills/ghats, etc. Vehicle performance was evaluated through periodic mass emissions before, after and during vehicle running-in, evaporative emissions and component rating before & after mileage accumulation.
This paper presents the outcome of systematic evaluation of E20 fuel, in comparison with commercial gasoline, conducted through laboratory evaluation as well as field trails on 4-wheeler (old and new) vehicles.
A robust methodology was developed and followed for evaluation of alternate fuels in a holistic manner. The study revealed vital information on the performance of E20 fuel, in comparison to commercial gasoline, in terms of emissions, operating performance and material compatibility.