E20 petrol can cut mileage by 2-6%, government says, as Kejriwal seeks price relief

E20 petrol is now dispensed nationwide under a policy that took effect on April 1, and the official mileage answer is a range, not a yes or no. Road Transport and Highways Minister Nitin Gadkari says petrol blended with 20% ethanol can reduce fuel economy by 2-6%, with the band moving by vehicle category and vintage.

So does E20 lower your mileage? For compliant vehicles, the reduction is about 1-2%, because ethanol carries less energy per litre than pure petrol. For some older vehicles designed for E10, the central government puts the fall closer to 3-5%, while saying E20 has not caused widespread engine damage.

The 2-6% band, and why it moves

Gadkari informed parliament-linked discussion that E20 can cut fuel economy by 2 to 6 per cent depending on vehicle category and vintage. A separate government position says E20 has passed durability tests without engine failures, but still concedes fuel efficiency could decline by up to 6% depending on type and age. The oil ministry has used a narrower 3-5% figure for some vehicles, and says cleaner combustion, higher octane rating and energy security outweigh the impact.

In the social-media row over the rollout, Gadkari’s retort was: ‘You and I can’t check car’s mileage’. The Times of India captured the split neatly: one minister puts mileage drop due to E20 at 2-6%, another puts it at 3-5%.

What older cars face

The sharper hit is concentrated in older machines. The government has admitted that E20 can produce around a three to five per cent reduction in mileage in some older vehicles designed for E10. A government note reported by TheWire.in makes the same admission: E20 can reduce fuel economy by 3-5% in some vehicles.

The same debate reaches insurance and upkeep. E20 adoption affects vehicle compatibility, mileage, maintenance and insurance coverage for cars and two-wheelers, according to a CNBCTV18 report. The direct question — does E20 lower my mileage — has also been put to Mahindra, Toyota and Mercedes-Benz in a CarDekho round-up, though the automaker answers are separate from the official 2-6% range.

The bill question Kejriwal raised

Arvind Kejriwal, AAP national convener and former Delhi chief minister, said on Tuesday he had written to Prime Minister Narendra Modi on Monday over E20. His letter seeks reduced prices for E20 since the blend gives lower mileage, and asks for a review of the rollout for older cars. The Mint report frames it as a price issue, not just a technical one.

Forbes India has framed the cost side as what a 3-5% mileage drop does to a petrol bill. The strategic case for E20 remains unchanged in official statements: less dependence on imported crude oil, lower emissions, cleaner combustion and a higher octane rating. Kejriwal’s ask leaves the open point with the Centre — whether older-car owners get a price correction or a rollout review before the next mileage comparison reaches the pump.