General Studies Paper 3 (Science & Technology)
Question:- 44. Explain what is ethanol blending and what are the various generations of ethanol. Analyse the environmental and ecological benefits of ethanol blending of petrol in India. Answer in 250 words.
Aug 20, 2022



Ethanol is an agricultural by-product which is mainly obtained from the processing organic matter.  Ethanol in India is obtained primarily from sugarcane via a fermentation process. Blending ethanol with petrol to burn less fossil fuel while running vehicles is called ethanol blending. Currently, 10% of the petrol that powers Indian vehicles is ethanol.  The government of India has advanced the target for 20 per cent ethanol blending in petrol (also called E20) to 2025 from 2030.


LINKAGE POINT: Biofuels can be broadly categorized into the following four types depending upon how they are obtained:




  1. 1.First generation biofuels – made from sugar, starch, vegetable oil, or animal fats using conventional technology. Common first-generation biofuels include Bioalcohols, Biodiesel, Vegetable oil, Bioethers, Biogas.
  2. 2.Second generation biofuels – These are produced from non-food crops, such as cellulosic biofuels and waste biomass (stalks of wheat and corn, and wood). Examples include advanced biofuels like biohydrogen, biomethanol.
  3. 3.Third generation biofuels – These are produced from micro-organisms like algae.
  4. 4.Fourth generation biofuels – They are the amalgamation of genomically prepared microorganisms and genetically engineered feedstock. Cyanobacteria are engineered to increase the oil yield and are used for the efficient production of bioenergy.



The following are the perceived ecological and environmental benefits of ethanol blending of fuel for India:

  1. 1.Ethanol is high in oxygen content, which therefore allows an engine to more thoroughly combust fuel. It will decrease emissions of CO(carbon monoxide), Hydrocarbons, NOx (oxides of nitrogen), etc. as it burns more smoothly due to the presence of oxygen in the molecule itself.
  2. 2.Ethanol contains fewer volatile components than gasoline, which means fewer gas emissions from evaporation.
  3. 3.Relatively low Emissions will help achieve SDG targets and mitigate climate change.
  4. 4.Contributing to Swachh Bharat Mission by supporting the aggregation of non­food biofuel feedstocks such as waste biomass and urban waste- better use of damaged food grains . Also, it will reduce air pollution due to stubble burning in Northern India esp. Delhi, NCR as 2G ethanol refineries would collect the stubble from farmers which was earlier burnt. E.g. recent 2G ethanol plant in Panipat refinery.

Moreover, India is dependent on imports for about 82.1% of its crude oil requirement and to the extent of about 44.4% in the case of natural gas. Because ethanol is produced domestically—from domestically grown crops—it reduces India’s dependence on foreign oil and increases the nation’s energy independence. It is estimated that ethanol blending can save Rs 30,000 crore of foreign exchange per year. Ethanol production will also support farmers and creates domestic jobs. It will help the sugar mill owner to pay farmers their pending FRP for sugarcane. It will also mitigate the problem of low sugar prices in the international market.



Hence, ethanol blending of fuel is a win-win strategy for India. However, the challenge ahead lies in making vehicles E20 compliant and balancing between food and fuel security.