E20 petrol can reduce fuel economy by 2-6%: Nitin Gadkari

Petrol blended with 20% ethanol (E20) can reduce fuel economy by 2 to 6% depending on the vehicle category and vintage, Road Transport and Highways Minister Nitin Gadkari informed Parliament on Thursday (July 30, 2026).

The Union Minister, however, argued that tests for engine durability on a dynamometer and on-road vehicle tests have not shown any failures due to E20.

In a written reply to the Lok Sabha, Mr. Gadkari said E20 fuel provides better acceleration, improved ride quality and approximately 30% lower carbon emissions compared to E10 fuel.

Mr. Gadkari said a study to evaluate the effect of E20 on BS-III, BS-IV and BS-VI E10 (Gasoline) two-wheelers and four-wheelers was carried out jointly by ARAI, SIAM and Indian Oil Corporation Ltd (IOCL).

He said the study comprised of standard testing as per the respective certification requirements & customised test protocols developed along with the Original Equipment Manufacturers (OEMs).

“The fuel efficiency of vehicles may be reduced by 2 to 6% depending on the vehicle category and vintage. The tests for engine durability on a dynamometer and vehicle tests on road have not shown any failures due to E20,” the Minister said.

The rollout of E20 petrol (80% petrol, 20% ethanol) has drawn criticism from Opposition parties and some consumer groups, who have raised concerns about its impact on older vehicles not specifically designed for 20% ethanol blends.

Critics have questioned whether all vehicles are fully compatible with E20, flagged the possibility of reduced fuel efficiency and higher maintenance costs, and sought clarity on liability if engine or fuel-system problems arise.

The government has maintained that the transition has been phased and backed by extensive testing, while automobile manufacturers have said they continue to honour warranty claims for vehicles using E20 fuel. Opposition parties have repeatedly sought greater transparency on vehicle compatibility and consumer safeguards.

The Minister explained that the Ethanol blended petrol (EBP) programme has been implemented through a phased, scientifically validated and consultative process involving NITI Aayog, automobile manufacturers, Oil Marketing Companies (OMCs), Automotive Research Association of India (ARAI), Society of Indian Automobile Manufacturers (SIAM), Indian Institute of Petroleum (IIP) and other technical institutions.

In India, he said the ethanol blended petrol (EBP) programme commenced with a pilot in 2001, E5 was introduced in 2006, and although blending remained around 1.53% in 2013-14, it has since been increased progressively in a calibrated manner after creating the necessary production capacity, infrastructure and regulatory framework.

According to him, E15+ blended petrol has been in widespread use for over three-and-a-half years and E19-E20 fuel for over two-and-a-half years.

Mr. Gadkari noted that more than 20 crore two-wheelers and over 3 crore petrol cars have been operating on these blends without any verified evidence of widespread engine failure or vehicle breakdown attributable to ethanol blending.

“Manufacturer service data confirm that there is no abnormal corrosion, wear or reduction in vehicle life due to E20 fuel,” he said, adding that manufacturers continue to honour warranty obligations for vehicles using E20 fuel, providing further confidence in its safety and reliability.

BS, or Bharat Stage, refers to India’s vehicle emission standards that set limits on pollutants such as carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC) and particulate matter (PM).