No damage to engines, but mileage sees slight dip: Govt clarifies on E20 fuel concerns

The Ministry of Petroleum and Natural Gas has issued a detailed clarification in response to recent social media reports suggesting that 20 percent ethanol-blended petrol (E20) may be damaging engines and impacting vehicle performance. The ministry said that while a marginal drop in fuel efficiency is expected, there is no evidence of any damage to engines or critical vehicle components due to the adoption of E20.

According to the ministry, multiple scientific studies, including international research and testing by Indian institutions like the Automotive Research Association of India (ARAI), Indian Institute of Petroleum (IIP), and Indian Oil Corporation’s R&D division, have confirmed that E20 causes no significant differences in power, torque, or fuel consumption.

These studies tested both carbureted and fuel-injected vehicles across 100,000 kilometers and found no abnormal wear and tear, engine issues, or performance losses.

The clarification emphasized that E20-compliant vehicles have already been introduced in India. The Society of Indian Automobile Manufacturers (SIAM) has confirmed that vehicles built with upgraded components specifically designed for E20 have been available since April 2023.

For older vehicles, the ministry stated that the decrease in mileage is marginal — around 1 to 2 percent for those originally designed for E10 and calibrated for E20, and about 3 to 6 percent for others. This impact can be minimized further through engine tuning and improved materials.

Addressing concerns about material compatibility and corrosion, the ministry said safety standards for E20 are well-established under Bureau of Indian Standards (BIS) specifications and Automotive Industry Standards. In some older vehicles, minor parts such as rubber gaskets may need replacement after prolonged use — typically after 20,000 to 30,000 kilometers — but these are low-cost and manageable during regular servicing.

On the environmental front, the ministry reaffirmed that ethanol blending significantly reduces CO2 emissions and enhances India’s energy security. Ethanol is increasingly being sourced from diversified feedstock including surplus rice, maize, damaged food grains, and agricultural residues under the push for second-generation biofuels. Niti Aayog studies show greenhouse gas emissions are reduced by 65 percent with sugarcane-based ethanol and 50 percent with maize-based ethanol compared to petrol.

The ministry also highlighted technical advantages of ethanol. With a higher octane number than petrol, ethanol improves ride quality and performance, especially in modern engines that require higher-octane fuels. Additionally, its higher heat of vaporization leads to better air-fuel mixture density, enhancing engine efficiency.

From a policy perspective, the government underscored that the shift to E20 was not abrupt but followed a phased and transparent roadmap that has been publicly available since 2021. The rollout involved close coordination with automakers, fuel retailers, and standards agencies to ensure readiness across the value chain.