The Centre has reiterated that petrol blended with 20 per cent ethanol (E20) is safe for vehicles, even though it may lead to a marginal drop in fuel efficiency. Union Road Transport and Highways Minister Nitin Gadkari informed Parliament that extensive testing has not revealed any engine damage caused by the fuel.

In written responses submitted separately to the Lok Sabha and Rajya Sabha, Gadkari said scientific evaluations carried out by government agencies and automobile manufacturers concluded that E20 is compatible with most vehicles currently on Indian roads.

Mileage Impact Limited, Says Government

According to Gadkari, studies indicate that vehicles running on E20 petrol could experience a fuel efficiency reduction ranging from 2 to 6 per cent, depending on the vehicle's age and category.

The assessment was jointly conducted by the Automotive Research Association of India (ARAI), the Society of Indian Automobile Manufacturers (SIAM) and Indian Oil Corporation (IOCL). It included laboratory testing, road trials and manufacturer-approved evaluation methods covering two-wheelers and four-wheelers across BS-III, BS-IV and BS-VI emission standards.

The minister said durability tests and real-world driving evaluations did not identify any engine failures linked to the use of E20 fuel.

Older Vehicles May Need Minor Component Replacement

Addressing concerns about older vehicles, Gadkari said the studies found no requirement for engine modifications in cars or motorcycles operating on E20.

However, he noted that certain BS-III vehicles manufactured before 2016 may require replacement of some rubber components and gaskets over time. These changes, he said, can be carried out during routine servicing and do not indicate any major mechanical concern.

The research also reported no significant issues relating to vehicle performance, engine wear, corrosion, drivability, cold starting or compatibility with metal and plastic components.

Government Highlights Environmental Benefits

Apart from vehicle safety, the minister said E20 offers environmental advantages. According to the government's findings, the fuel delivers improved acceleration and smoother driving characteristics while reducing carbon emissions by nearly 30 per cent compared to E10 petrol.

E20 Rollout Backed by Scientific Studies

Gadkari said the Ethanol Blended Petrol (EBP) Programme has been implemented in phases after consultations involving NITI Aayog, oil marketing companies, automobile manufacturers, ARAI, SIAM, the Indian Institute of Petroleum (IIP) and other technical institutions.

He informed Parliament that an Inter-Ministerial Committee constituted by NITI Aayog in December 2020 thoroughly examined issues such as vehicle compatibility, fuel efficiency, emissions, engine calibration, durability and material performance before recommending higher ethanol blending.

The committee's roadmap, released in 2021, served as the foundation for the country's transition to E20 fuel.

Ethanol Programme Expanded Gradually

The minister noted that India's ethanol blending initiative began as a pilot project in 2001 before E5 fuel was introduced in 2006. Blending levels remained low until 2013-14, after which production capacity, infrastructure and policy support enabled a gradual increase.

According to Gadkari, E15+ fuel has been widely used for over three years, while E19-E20 blends have already been in circulation for more than two-and-a-half years.

Before E20 was rolled out nationwide in April 2026, the government conducted extensive laboratory research, durability assessments and field trials covering fuel systems, corrosion resistance, emissions, engine performance and overall vehicle reliability.

Highlighting the scale of adoption, Gadkari said over 20 crore two-wheelers and more than three crore petrol cars have already operated on ethanol-blended fuel without verified evidence of widespread engine failures linked to ethanol use.

He added that vehicle manufacturers continue to honour warranty claims for vehicles running on E20, reinforcing confidence in the fuel's long-term safety and reliability.