IIT Kanpur claims E20 petrol doesn't harm engine performance

The Indian Institute of Technology (IIT) Kanpur on Tuesday (July 14) claimed that its research found no evidence that E20 petrol harms engine performance or fuel efficiency in either existing or older vehicles.

The findings come amid growing debate over the nationwide rollout of E20 petrol, a blend of 20 per cent ethanol and 80 per cent petrol, which has sparked widespread discussion over its impact on vehicles.

Also read: E20 petrol row: Gadkari says only dealers, not consumers, can check mileage

The study follows the Union Ministry of Petroleum and Natural Gas's clarification last week that while E20 fuel may reduce mileage by up to 5 per cent in some vehicles, the impact is offset by benefits such as lower lifecycle carbon emissions.

'Only up to 5% decrease'

Dhruv Raj Karana, Project Scientist at the Engine Research Laboratory in IIT Kanpur's Department of Mechanical Engineering, said the institute's research found that the reduction in fuel efficiency with E20 is less than 5 per cent.

Speaking to PTI, he said the observed mileage drop could also be influenced by factors other than the fuel itself and that similar variations can occur "even if back-to-back tests are repeated with pure petrol."

Karana added that extensive testing found no evidence of engine damage, corrosion or other technical issues caused by E20 fuel.

Dismisses social media claims

Karana described claims circulating on social media that E20 damages vehicles as "scientifically unfounded" and urged motorists to rely on their vehicle manufacturer's manual and the Ministry of Petroleum and Natural Gas's guidelines instead of unverified online posts.

Also read: Most NDA supporters reluctant to adopt E20 petrol: C-Voter survey

He also said IIT Kanpur's Engine Research Laboratory, headed by Professor Avinash Kumar Agarwal, has been conducting extensive research on ethanol-blended fuels. The team has also successfully tested E85 fuel, which contains 85 per cent ethanol, although such blends require specially designed engines and compatible fuel systems.

Fuel efficiency

According to Karana, the institute's studies found no significant drop in fuel efficiency attributable to E20. He said variations in mileage are influenced more by driving habits, road conditions and vehicle maintenance than by the fuel itself.

In a recent question-and-answer document issued to address concerns over the Ethanol Blended Petrol Programme, the Petroleum Ministry described E20 as a "cleaner, higher-quality and more efficient fuel" than E10 or pure petrol. It said the nationwide rollout followed years of scientific testing, consultations with automobile manufacturers and the expansion of domestic ethanol production.

Why E20 remains controversial

Despite the government's assurances, the nationwide rollout has triggered concerns among vehicle owners.

Many motorists and social media users have claimed the real-world drop in fuel efficiency is significantly higher than the 3–5 per cent acknowledged by the Petroleum Ministry.

Also read: Policy over choice? Experts flag consumer risks in E20 fuel rollout | AI With Sanket

Others have raised concerns that ethanol's hygroscopic nature, its tendency to absorb moisture, could increase the risk of corrosion, fuel pump failures and rough idling, particularly in vehicles manufactured before April 2023 that were not designed to run on E20 fuel.

Some vehicle owners have also expressed concerns that engine failures allegedly linked to ethanol-blended fuel could affect warranty coverage or insurance claims.

Meanwhile, the Supreme Court recently dismissed a public interest litigation filed by vehicle owners seeking mandatory fuel labelling and the continued availability of unblended E0 petrol, holding that fuel blending is a policy decision within the government's domain.