Ethanol blending in petrol: A techno - commercial overview

Abstract

Due to fast depletion of fossil fuels, there is a need to explore ways to circumvent or to reduce their use. Largely populated countries like India need to be more concerned about this. In the last decade, India started blending ethyl alcohol (ethanol, EtOH) in petrol (gasoline). Presently Indian petrol suppliers blend about 10 % EtOH by volume, which is expected to rise to 20 % by 2024. Like any engineering solution, ethanol blending is accompanied by own merits and demerits. This review aims at assessing the effect of ethanol blending in spark ignition internal combustion engines based on technical and commercial aspects. Effect of EtOH blending on the engine performance and emission has been discussed in detail. Various parameters related to fuel quality like the concentration of EtOH present and the amount of water present - which affect the performance - are also discussed. EtOH blending affects the emission and compatibility issues might arise which is discussed. Routes of production of EtOH may change the techno - commercial aspects of any process. This aspect is discussed along with the amount of EtOH blended, since this may help in shaping up the future policy decisions. Contradictions and gaps are highlighted to provide a direction for future studies. Indian and global scenario is also discussed to a considerable detail.