With the ever increasing world population and hence the more and more use of vehicles and automobiles, environmental pollution is rapidly increasing and has become one of the major challenges of the century. Also the fossil fuel reserves are limited and these are being rapidly exhausted, thus energy security for the future generations is another key concern. Thus scholars around the world are looking for alternative fuels which could be substituted for these fossil fuels and also do not pollute the environment. The most appropriate solution is the widespread use of the resources that nature provides and which could be replenished. It is imperative that, as soon as possible, we find and exploit these new sources of energy. In this context, biomass will play a crucial role in the transition from fossil to renewable fuels. Biomass is renewable, available in large quantities, and helps to recycle the carbon already released into the atmosphere. Ethanol is the most prominent natural resource, when produced from sugarcane and cane. Added to petrol, ethanol is used as a fuel in a large number of countries, and for this reason is considered one of the most viable options to reduce the excessive reliance on fossil fuels.
This study investigates the effects of ethanol-blended gasoline on emissions characteristics of a single–cylinder Spark Ignition (SI) Engine for different compression ratios. The three blends (E5, E10, E15) were prepared in the laboratory. No modifications on the engine and its parts have been made. Moreover, no major problems like knocking were encountered during the engine operation. The emission tests were measured using an exhaust gas analyser and smoke-meter. The experimental results proved that the blending increased brake thermal efficiency more than a sole fuel, such as gasoline. The emission tests found that the CO emissions slightly decreased, while HC increased moderately whereas CO2 and NOx appreciably increased. Experimentation concludes that use of ethanol can effectively help in fossil fuel compensation and can improve the emission characteristics as well.