IIT Kanpur says E20 petrol does not significantly cut mileage or harm engines
IIT Kanpur researchers said tests found E20 petrol does not significantly reduce mileage or damage engines. The findings challenge online claims and back the wider rollout of ethanol-blended fuel.

Amid concerns over the nationwide rollout of 20 per cent ethanol-blended petrol, or E20, researchers at IIT Kanpur on Tuesday said their studies found no significant drop in fuel efficiency and "no evidence" that the fuel harms engines in either existing or older vehicles.
The claim comes days after the Oil Ministry said E20 can reduce mileage by up to 5 per cent in some vehicles, but added that the impact is outweighed by benefits including lower life cycle carbon emissions.
Dhruv Raj Karana, Project Scientist at the Engine Research Laboratory in IIT Kanpur's Department of Mechanical Engineering, told PTI that the fall in fuel efficiency with E20 was less than 5 per cent in the institute's research. He said the up to 5 per cent drop could be caused by factors other than fuel and that a similar result can be obtained "even if back to back tests are repeated with pure petrol".
Karana said "extensive testing" showed that E20 does not cause engine damage, corrosion or other technical problems. He dismissed claims on social media about E20 damaging vehicles as "scientifically unfounded" and advised motorists to follow their vehicle manufacturer's manual and the Ministry of Petroleum and Natural Gas guidelines instead of relying on unverified online posts.
He also said IIT Kanpur's Engine Research Laboratory, headed by Professor Avinash Kumar Agarwal, has been carrying out extensive research on ethanol-blended fuels. The team has also successfully tested E85 fuel, which contains 85 per cent ethanol, though he said such high blends require specially designed engines and compatible fuel systems.
Karana said the institute's studies found no significant drop in fuel efficiency due to E20 and that any variation in mileage was influenced more by driving habits, road conditions and vehicle maintenance than by the fuel itself.
In a detailed question-and-answer document issued recently to counter criticism of the Ethanol Blended Petrol Programme, the ministry said E20 was a "cleaner, higher-quality and more efficient fuel" than E10 or pure petrol and had been rolled out only after "years of scientific testing, consultations with automobile manufacturers and the expansion of domestic ethanol production".
Amid concerns over the nationwide rollout of 20 per cent ethanol-blended petrol, or E20, researchers at IIT Kanpur on Tuesday said their studies found no significant drop in fuel efficiency and "no evidence" that the fuel harms engines in either existing or older vehicles.
The claim comes days after the Oil Ministry said E20 can reduce mileage by up to 5 per cent in some vehicles, but added that the impact is outweighed by benefits including lower life cycle carbon emissions.
Dhruv Raj Karana, Project Scientist at the Engine Research Laboratory in IIT Kanpur's Department of Mechanical Engineering, told PTI that the fall in fuel efficiency with E20 was less than 5 per cent in the institute's research. He said the up to 5 per cent drop could be caused by factors other than fuel and that a similar result can be obtained "even if back to back tests are repeated with pure petrol".
Karana said "extensive testing" showed that E20 does not cause engine damage, corrosion or other technical problems. He dismissed claims on social media about E20 damaging vehicles as "scientifically unfounded" and advised motorists to follow their vehicle manufacturer's manual and the Ministry of Petroleum and Natural Gas guidelines instead of relying on unverified online posts.
He also said IIT Kanpur's Engine Research Laboratory, headed by Professor Avinash Kumar Agarwal, has been carrying out extensive research on ethanol-blended fuels. The team has also successfully tested E85 fuel, which contains 85 per cent ethanol, though he said such high blends require specially designed engines and compatible fuel systems.
Karana said the institute's studies found no significant drop in fuel efficiency due to E20 and that any variation in mileage was influenced more by driving habits, road conditions and vehicle maintenance than by the fuel itself.
In a detailed question-and-answer document issued recently to counter criticism of the Ethanol Blended Petrol Programme, the ministry said E20 was a "cleaner, higher-quality and more efficient fuel" than E10 or pure petrol and had been rolled out only after "years of scientific testing, consultations with automobile manufacturers and the expansion of domestic ethanol production".