E20 Petrol Concerns Grow: Why CEA Wants E10 Back at Fuel Pumps
Chief Economic Adviser V Anantha Nageswaran has called for greater flexibility in India’s ethanol-blending policy, suggesting that the government consider making a lower-ethanol petrol option available for older vehicles.
In an opinion article co-authored with Akash Poojari, a consultant in the Department of Economic Affairs, Nageswaran said petrol with a lower ethanol blend, such as E10, could help protect millions of ageing two-wheelers while allowing the country to continue with its E20 programme.
The recommendation comes amid an ongoing debate over the impact of E20 petrol, which contains 20% ethanol. E20 has been the sole petrol variant available at fuel stations across India since April 1 as part of efforts to reduce crude oil imports, support domestic agriculture and cut emissions.
While the government has repeatedly rejected claims of widespread engine damage caused by E20, some vehicle owners—particularly those using older, non-BS-VI vehicles—have reported concerns about mileage, performance and damage to certain components.
Nageswaran and Poojari said the available evidence does not establish that E20 causes widespread engine damage. However, they noted that older two-wheelers may face specific problems because their fuel systems were not designed for higher ethanol concentrations.
The authors estimated that India has around 75-80 million older two-wheelers manufactured before the BS-IV era that use carburettors. Such systems cannot automatically adjust to the additional oxygen introduced by ethanol-blended fuel. As a result, engines can receive a relatively leaner fuel-air mixture, potentially causing them to run hotter.
Another concern involves older rubber seals and other fuel-system components that may not be compatible with ethanol. Prolonged exposure to ethanol can cause some of these materials to deteriorate.
Given these challenges, the authors recommended making a lower-blend petrol such as E10 available alongside E20. They argued that this would provide protection for older vehicles without requiring the government to abandon its broader ethanol-blending goals.
The authors also suggested that the existing vehicle fleet should be protected while retrofit programmes gradually equip older vehicles with ethanol-compatible components. Although such upgrades may not be particularly expensive, completing them across millions of ageing vehicles could take years.
The article also addressed concerns about fuel efficiency. Ethanol contains less energy than conventional petrol, meaning E20 can result in somewhat lower mileage. However, the authors estimated the overall energy penalty at about 6-7%, rather than the significantly higher reduction sometimes claimed on social media.
They further pointed to testing conducted in India and the US, which they said found no evidence of increased engine wear in vehicles designed to operate with E20.
At the same time, Nageswaran and Poojari questioned whether India should raise ethanol blending beyond the E20 target. They cautioned that higher blending levels could increase competition between ethanol production and food crops.
According to the article, maize now contributes around half of India's ethanol feedstock, while grains collectively account for nearly 67%. Increased demand for maize could compete with crops such as soybean, groundnut and mustard for agricultural land.
Such competition could complicate India's efforts to reduce its reliance on edible-oil imports, the authors noted.
The proposal for a lower-blend petrol is therefore aimed at balancing India's long-term ethanol objectives with the practical challenges faced by owners of older vehicles. Offering E10 alongside E20, the authors argued, could protect the existing vehicle fleet while India's transition to ethanol-compatible technology continues. ALSO READ: Is India's E20 fuel rollout damaging engines?
