Ethanol-Blended Diesel Fails Safety Test
Ethanol-blended diesel has failed the required safety specifications, forcing the Centre to put any wider rollout of the fuel on hold for now.
Minister of State for Petroleum and Natural Gas Suresh Gopi informed Parliament that scientific assessments conducted by public-sector oil marketing companies found a major technical problem with the fuel: adding ethanol significantly reduced diesel’s flash point.
The assessments were carried out through the research and development centres of state-run oil companies in association with accredited laboratories and automobile manufacturers.
Flash Point Drops Sharply With Ethanol
The key problem identified during testing was the fuel’s flash point.
The addition of ethanol caused the flash point of diesel to fall significantly, meaning the ethanol-diesel blend failed to meet the mandatory safety specification applicable to diesel.
Because of this failure, the government has effectively ruled out wider use of ethanol-blended diesel unless the technical and safety concerns are resolved.
The issue is particularly important because flash point is a critical safety characteristic for fuels during storage, handling and transportation.
Isobutanol Not Being Blended With Diesel
The government was also asked whether isobutanol was being used as an alternative for blending with diesel.
Gopi clarified that isobutanol is presently not being blended with diesel.
This means there is currently no alternative alcohol-based diesel blending programme of this nature in operation.
India Still Wants More Ethanol Uses
The setback for ethanol-blended diesel comes as India continues to look for additional uses for domestically produced ethanol.
The government is already examining ethanol as a potential cooking fuel, which could help reduce dependence on imported LPG while creating another outlet for domestic ethanol production.
The LPG Equipment Research Centre, a joint venture of Indian Oil Corporation, Hindustan Petroleum Corporation and Bharat Petroleum Corporation, along with public-sector oil marketing companies, is working on developing ethanol-based clean cooking alternatives.
10.5 Billion Litres Of Ethanol Sought
India’s ethanol programme continues to expand through petrol blending.
State-run oil marketing companies floated their first tender in September 2025 to procure around 10.5 billion litres of ethanol for the 2025-26 ethanol supply year.
The tender attracted offers for nearly 17.6 billion litres, around 68% more than the quantity sought. The companies subsequently allocated 10.485 billion litres to 378 registered suppliers.
The figures show the scale of India’s ethanol production and supply ecosystem, even as the government faces technical limitations in finding additional transport-fuel applications.
No Decision To Increase Petrol Blending Beyond E20
The government has also said it has taken no decision to increase ethanol blending in petrol beyond the existing 20% target.
Any future increase will be considered only after detailed scientific and technical studies, along with consultations involving automobile manufacturers, oil marketing companies and research institutions.
For now, therefore, ethanol-blended diesel remains off the table for wider deployment because of the safety problem identified during testing.
Summary
Ethanol-blended diesel has failed required safety specifications after testing showed that adding ethanol significantly lowers diesel’s flash point. Minister Suresh Gopi told Parliament that state-run oil companies conducted scientific assessments with accredited laboratories and automobile manufacturers. Isobutanol is not currently being blended with diesel. The government is instead examining ethanol for cooking fuel while continuing its existing ethanol blending programme for petrol.
