Bring back E10 for older vehicles: CEA

India should bring back a petrol variant with a lower ethanol blend to protect millions of older vehicles, according to a Government adviser, marking one of the strongest calls yet from a senior official for greater consumer choice amid growing concerns over the country’s ethanol policy.

E20 petrol, containing 20 per cent ethanol, was rolled out last year and has been the only petrol variant available for sale at fuel stations across India since April 1 as part of efforts to cut India’s dependence on imported oil, support domestic agriculture and reduce emissions.

Some users, particularly of non-BS-VI vehicles, have, however, reported a drop in vehicular performance and damage to auto parts — a claim the government has repeatedly dismissed as far from the truth. Oil Ministry has maintained that it’s not feasible to build and maintain infrastructure to supply multiple grades of fuel.

Chief Economic Advisor (CEA) V Anantha Nageswaran, alongside Akash Poojari, who is a consultant in the Department of Economic Affairs, in an opinion piece said the evidence did not support widespread claims that E20 damages vehicle engines, but argued that the policy could pose problems for India’s large fleet of older two-wheelers.

Dismissing complaints outright would be “a mistake because beneath the noise lies a real problem and a much larger question,” they wrote in the Indian Express.

With a disclaimer that the opinion they were expressing was personal, the two authors said India has roughly 75 to 80 million older two-wheelers built before BS-IV that run on carburettors. A carburettor cannot sense the extra oxygen in the blend and adjust for it, so on E20, the engine draws in too little fuel for the air it draws in and runs hot.

Further, older rubber seals that are not rated for ethanol are a separate problem, as they degrade on contact with the fuel regardless of engine temperature, they wrote.

The authors recommended restoring a lower-blend fuel, such as E10, alongside E20 to protect older vehicles while allowing the government to continue its ethanol programme.

The Government should “protect the existing fleet while the retrofit programme catches up,” the opinion piece said.

Ethanol contains less energy than petrol, meaning E20 can reduce the distance a vehicle travels on a litre of fuel. But the authors estimated the overall energy penalty at around 6-7 per cent, rather than the much larger reduction sometimes claimed online.

Testing in the United States and India has also found no evidence of increased engine wear in vehicles compatible with E20, the authors said.

However, older two-wheelers that use carburettors may face separate challenges because their fuel systems were not designed to adjust automatically to the higher oxygen content associated with ethanol-blended petrol. Older rubber seals that are not ethanol-compatible may also deteriorate when exposed to the fuel.

Retrofitting those vehicles with compatible components would be relatively inexpensive but would take years to complete across India’s ageing vehicle fleet, according to the authors.

The opinion piece also questioned whether India should increase ethanol blending beyond the current E20 target, arguing that higher blending levels could intensify competition between fuel production and food crops.

Maize now accounts for about half of India’s ethanol feedstock, while grains together account for nearly 67 per cent, it said. Maize competes with oilseed crops such as soybean, groundnut and mustard for agricultural land, potentially complicating India’s efforts to reduce its dependence on edible-oil imports.

The authors also raised concerns over water use, saying policymakers should focus on the use of “blue water” - water drawn from rivers, canals and groundwater - rather than headline estimates that also include rainfall.

The climate benefits of increasing blending beyond E20 are also not clear-cut, they said, as studies differ on the emissions impact of grain-based ethanol once cultivation and processing are taken into account.

India’s ethanol programme has nevertheless delivered significant benefits, including helping clear sugarcane arrears, supporting rural incomes and providing a guaranteed market for producers. Holding the blend at E20 also carries costs because distillery capacity and investments have been built around expectations of rising ethanol demand, the authors said.

The authors argued that policymakers should prioritise measures that can be reversed relatively easily - such as procurement prices, water-use rules and the availability of lower-blend petrol - before making further changes to the ethanol blend target.

“The engine row we witnessed was never the real argument. The real one is about what we choose to grow, and what we will not be able to take back,” the opinion piece said.

Nageswaran and Poojari said India should restore a lower-blend option such as E10, address pricing and water-use incentives that favour maize over competing crops, reconsider edible-oil import duties and hold the ethanol blend at E20 until the food-versus-fuel trade-off has been fully assessed.