NITI Aayog's 2021 roadmap had flagged mileage, compatibility issues with E20
It noted that while rubber and plastic components used in existing vehicles were compatible with E10 fuel, E20 would require elastomers, plastics and certain metallic components to be compatible with the higher ethanol content, necessitating engineering changes by automobile manufacturers.
- Jul 7, 2026,
- Updated Jul 7, 2026 10:33 AM IST
Long before E20 petrol became the default fuel across India, the government's ethanol blending roadmap had acknowledged lower fuel economy in legacy vehicles, the need for E20-compatible components and a phased transition for the automobile industry.
As the nationwide rollout of E20 petrol comes under intense public scrutiny over concerns around fuel economy and vehicle compatibility, a government roadmap prepared nearly five years ago had already identified many of the technical challenges associated with higher ethanol blends.
The 'Roadmap for Ethanol Blending in India 2020-25', released by NITI Aayog in collaboration with the Ministry of Petroleum and Natural Gas in June 2021, laid out the technical, regulatory and manufacturing changes required for India's transition from E10 to E20 petrol.
Among its key observations, the report estimated that existing four-wheelers calibrated for E10 could witness a fuel economy reduction of around 6-7 per cent when operated on E20 fuel, while two-wheelers could see a decline of 3-4 per cent. Vehicles specifically designed and calibrated for E20, however, were expected to experience a significantly lower reduction of 1-2 per cent.
The report also acknowledged that higher ethanol blends would require changes in vehicle components. It noted that while rubber and plastic components used in existing vehicles were compatible with E10 fuel, E20 would require elastomers, plastics and certain metallic components to be compatible with the higher ethanol content, necessitating engineering changes by automobile manufacturers.
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Recognising the scale of the transition, the roadmap recommended a phased implementation, giving vehicle manufacturers sufficient time to redesign engines, validate components, strengthen supply chains and prepare production facilities for higher ethanol blends.
The report also proposed that the rollout of E20 should be accompanied by a clearly defined transition strategy for the existing vehicle fleet. It recommended that the Ministry of Petroleum and Natural Gas notify a plan for the continued availability of lower ethanol blends for older vehicles during the transition period.
Long before E20 petrol became the default fuel across India, the government's ethanol blending roadmap had acknowledged lower fuel economy in legacy vehicles, the need for E20-compatible components and a phased transition for the automobile industry.
As the nationwide rollout of E20 petrol comes under intense public scrutiny over concerns around fuel economy and vehicle compatibility, a government roadmap prepared nearly five years ago had already identified many of the technical challenges associated with higher ethanol blends.
The 'Roadmap for Ethanol Blending in India 2020-25', released by NITI Aayog in collaboration with the Ministry of Petroleum and Natural Gas in June 2021, laid out the technical, regulatory and manufacturing changes required for India's transition from E10 to E20 petrol.
Among its key observations, the report estimated that existing four-wheelers calibrated for E10 could witness a fuel economy reduction of around 6-7 per cent when operated on E20 fuel, while two-wheelers could see a decline of 3-4 per cent. Vehicles specifically designed and calibrated for E20, however, were expected to experience a significantly lower reduction of 1-2 per cent.
The report also acknowledged that higher ethanol blends would require changes in vehicle components. It noted that while rubber and plastic components used in existing vehicles were compatible with E10 fuel, E20 would require elastomers, plastics and certain metallic components to be compatible with the higher ethanol content, necessitating engineering changes by automobile manufacturers.
DON'T MISS | Amid E20 debate, Centre evaluating phased rollout of E25 petrol by 2029
Recognising the scale of the transition, the roadmap recommended a phased implementation, giving vehicle manufacturers sufficient time to redesign engines, validate components, strengthen supply chains and prepare production facilities for higher ethanol blends.
The report also proposed that the rollout of E20 should be accompanied by a clearly defined transition strategy for the existing vehicle fleet. It recommended that the Ministry of Petroleum and Natural Gas notify a plan for the continued availability of lower ethanol blends for older vehicles during the transition period.