Chief Economic Adviser V. Anantha Nageswaran has advocated restoring E10 petrol at fuel stations alongside E20, arguing that the lower ethanol blend is essential to safeguard an estimated 75–80 million older two-wheelers currently at risk under India's accelerated ethanol blending programme. His recommendation, published in an article in The Indian Express, comes as public debate over E20's impact on engine health intensifies across social media.

The Core Concern: Carburettor-Era Vehicles

Nageswaran identified a specific and, he argued, genuine vulnerability in India's older vehicle fleet — two-wheelers manufactured before the BS4 emission norms that rely on carburettors rather than fuel-injection systems. A carburettor, he explained, cannot sense the additional oxygen present in ethanol blends and automatically adjust the fuel-air mixture. On E20, such engines draw in too little fuel relative to the air intake, causing them to run hotter than designed. Older rubber seals that are not ethanol-compatible may also degrade when exposed to higher ethanol concentrations.

The CEA stressed that this cohort of vehicles — numbering between 75 million and 80 million — represents a real-world policy gap that the original ethanol roadmap had anticipated but not adequately addressed. 'The original roadmap anticipated this and requested that a lower-blend fuel remain on sale for these vehicles, but that fuel quietly vanished from the pumps and needs to return,' he wrote.

What Nageswaran Actually Proposed

The adviser's recommendation is straightforward: restore E10 as a parallel option at pumps, rather than replacing E20. 'Restoring a lower blend at the pumps, say, E10, alongside the option to buy E20, would calm most public concern, lower total ethanol use instead of raising it, and protect the existing fleet while the retrofit programme catches up,' he wrote.

Notably, Nageswaran also pushed back on what he described as exaggerated claims circulating online. He noted that ethanol carries roughly two-thirds the energy content of petrol, meaning E20 results in an energy penalty of approximately 7 per cent — not the far steeper mileage loss widely cited on social media platforms. Testing conducted in both the US and India, he said, found no increased engine wear in vehicles not rated for E20.

Broader Policy Caution on Ethanol Blending

Beyond the immediate fleet-protection argument, Nageswaran urged the government to hold at E20 and conduct a thorough cost-benefit assessment of the food-versus-fuel trade-off before pushing blending ratios higher. He flagged unresolved distortions in pricing, water use, and edible-oil policy as issues that must be addressed in tandem with any expansion of the ethanol blending programme.

This comes amid India's broader push to reach 20 per cent ethanol blending in petrol nationwide — a target that has been advanced over the years as part of the country's energy transition and farm income support strategy. Critics and independent analysts have long warned that rapid scaling of food-crop-based ethanol risks straining domestic sugar and grain supplies.

What Happens Next

The CEA's article does not carry the weight of a formal policy directive, but recommendations from the office of the Chief Economic Adviser typically inform budget and sectoral policy discussions. Industry bodies representing two-wheeler manufacturers and fuel retailers are likely to weigh in as the debate gains traction. The government's response — particularly from the Ministry of Petroleum and Natural Gas and the Ministry of Road Transport and Highways — will determine whether E10 makes a formal return to forecourts.