The government has mandated the sale of petrol with up to 20 per cent ethanol and a minimum Research Octane Number (RON) of 95 across all states and Union Territories from April 1, 2026.
The oil ministry in a February 17 notification, said, “the central government hereby directs that oil companies shall sell ethanol-blended motor spirit (petrol) with percentage of ethanol up to 20 per cent as per the Bureau of Indian Standards specifications and having minimum Research Octane Number (RON) of 95, in states and the Union Territories”.
The central government can allow exceptions in special situations, for specific regions and for a limited time.
Ethanol is made from sugarcane, maize, or grain. It is renewable, domestically produced and has cleaner burning than pure petrol.
The government has mandated ethanol blending in petrol to help cut oil imports as also reduce emissions. Such a mandate also supports farmers as it boosts demand for sugarcane, maize and agricultural surplus.
Most vehicles manufactured in India from 2023-2025 onward are designed to run on E20 and no major issues are expected, industry officials said.
Older vehicles may however see a slight drop in mileage (3-7 per cent). Also rubber/plastic component may wear.
The insistance on minimum RON 95 is to prevent engine damage.
RON, or Research Octane Number, is a measure of a fuel’s resistance to engine knocking (pre-ignition). Knocking happens when fuel burns unevenly inside the engine, causing pinging sound, loss of power and possible engine damage over time.
The higher the RON, the more resistant the fuel is to knocking.
In simple terms, octane is like a fuel’s ‘self-control under pressure’ – higher RON means fuel stays stable under high compression.
Ethanol naturally has high octane value (around 108 RON). Blending 20 per cent ethanol in petrol, increases knock resistance.
Encouraged by India achieving 10 per cent ethanol doping in petrol in June 2022 – five months ahead of the target date – the government advanced 20 per cent blending to 2025-26 from 2030. Most pumps in the country now sell E20 or petrol blended with 20 per cent ethanol.
According to the oil ministry, since 2014-15 India has saved more than ₹1.40 lakh crore in foreign exchange through petrol substitution.
