E20 petrol won't affect fuel efficiency, may boost performance, says govt

Refuting claims that E20 petrol affects fuel efficiency, the Ministry of Petroleum and Natural Gas highlighted E20 petrol's environmental benefits, improved engine performance

   

The Ministry of Petroleum and Natural Gas has rejected reports suggesting that E20 petrol -- fuel blended with 20 per cent ethanol -- leads to a reduction in fuel efficiency.

 

In a social media post, the ministry stated that such claims are factually incorrect and lack support from scientific research. It explained that although ethanol possesses a lower energy density than petrol, the effect on mileage is minimal.

 

What is E20 petrol?

 

E20 petrol is a mixture comprising 20 per cent ethanol and 80 per cent petrol. Ethanol is a type of alcohol-based fuel commonly produced from crops such as sugarcane. While latest vehicles are designed to handle such fuel blends, most older vehicles in India are typically configured for E10 petrol, which contains 10 per cent ethanol.

 

 

Survey points to concerns from vehicle owners

 

The clarification from the ministry comes amid a recent survey, which indicated that a majority of Indian petrol vehicle owners are opposed to the government’s mandate on E20 petrol. The survey received more than 36,000 responses from petrol vehicle owners across 315 districts. According to the findings, two out of three owners of vehicles bought in 2022 or earlier reported a decline in fuel efficiency in 2025 compared to previous years.

 

No major issues with legacy vehicles

 

"Material compatibility tests by Automotive Research Association of India (ARAI), Indian Institute of Petroleum (IIP) and Indian Oil Corporation  have confirmed that legacy vehicles also showed no significant variations, performance issues or abnormal wear-and-tear when operated with E20. Moreover, E20 fuel passed hot and cold tests without any engine damage," the ministry said.

 

Marginal drop in efficiency, offset by new tech

 

The ministry noted that for vehicles originally designed for E10 petrol but calibrated for E20, fuel efficiency may decline by 1 to 2 per cent. In other vehicles, the drop may be in the range of 3 to 6 per cent. However, this reduction can be further minimised through improved engine tuning and the use of E20-compatible components, which have already been adopted by leading automobile manufacturers.

 

SIAM confirms availability of E20-ready vehicles

 

The Society of Indian Automobile Manufacturers (SIAM) has confirmed that vehicles designed to comply with E20 fuel standards, equipped with upgraded components, have been in operation on Indian roads since April 2023, the ministry said.

 

E20-tuned vehicles deliver enhanced performance: Ministry

 

The ministry also highlighted ethanol’s role in enhancing vehicle performance. Ethanol has a higher octane rating (108.5) compared to petrol (84.4), which contributes to improved engine performance and better ride quality in newer vehicles. It added that vehicles specifically tuned for E20 petrol demonstrate even greater performance levels. Ethanol's higher heat of vaporisation reduces the temperature within the intake manifold, thereby increasing the density of the air-fuel mixture and enhancing engine efficiency.