The claim spread quickly at the end of June, though the Attorney General’s office denied it the next day.
At the end of June 2026 a claim about E20 petrol moved fast across Indian social media. The government, it said, had told the Supreme Court that its 20 percent ethanol blending programme was an experiment. To anyone already unhappy about E20 petrol, it read as an admission.
Where the Claim Came From
Reports on 30 June 2026 said the Attorney General had used that word at a hearing.
The setting was procedural. Government lawyers had sought the transfer of ethanol cases, to prevent parallel proceedings and the risk of clashing rulings. So the court held that transfer petitions should be filed. It also held that the existing position on ethanol supply for 2025-26 would continue.
What the Attorney General’s Office Said
On 1 July the Attorney General’s office issued a clarification. It said the reports were wrong, and that the government had not described the programme that way.
That clarification did not travel nearly as far as the original claim.
What Is Established About E20 Petrol and Mileage
The mileage question is separate, though there are figures on the record for it.
In 2014-15 the Automotive Research Association of India ran a study with the Indian Institute of Petroleum and Indian Oil. The Ministry of Heavy Industries funded it. It found a drop in fuel economy of up to 6 percent, depending on vehicle type. The test cars still started and drove fine on both plain petrol and E20.
The Society of Indian Automobile Manufacturers put the drop at 2 to 4 percent in August 2025. Meanwhile the Ministry of Petroleum told the Rajya Sabha that blended petrol does not affect compatibility or cause unusual wear.
What Is Still Being Argued
On 1 September 2025 the Supreme Court threw out a petition that had asked for plain petrol to stay on sale at fuel stations. The bench led by the Chief Justice would not take it up.
A further petition filed in July 2026 asks for something narrower. It wants pumps and bills to show the ethanol content. It also wants a public list of which vehicles can take it, plus warranty and insurance cover for older cars.
The Wise Take
Two different arguments have run together here, so separating them helps. Whether the government called its own programme an experiment is a question about what happened in court. The Attorney General’s office has denied it. Whether E20 petrol cuts mileage is a question with real measurements behind it. The answer there is yes, by somewhere between two and six percent, depending on whose figure you take and which vehicle you drive. Now, the claim that spread was the one no driver could check. The one that can be checked is still waiting for a list.
