E100? Govt wants to go beyond E20 amid concerns over impact of ethanol on older vehicles

India’s aggressive push to expand ethanol blending in petrol—aimed at cutting crude oil imports amid ongoing West Asia-related supply disruptions—is now raising practical concerns for millions of vehicle owners, according to a report by The Times of India.

The government has been strongly advocating higher ethanol blending under its Ethanol Blended Petrol (EBP) programme, positioning it as a key pillar of energy security. Officials argue that the initiative has already delivered significant gains, helping India save nearly 4.5 crore barrels of crude oil annually and reducing foreign exchange outflow by around Rs 1.65 lakh crore so far.

However, the transition is not without challenges—particularly for vehicles that are not fully compatible with higher ethanol blends.


A major concern flagged in the NITI Aayog roadmap on E20 adoption is the potential impact on vehicle performance. According to the report, vehicles originally designed for E10 fuel (10% ethanol blending) but calibrated for E20 may see a 1–2% drop in mileage. This is especially relevant for a large segment of vehicles manufactured between 2012 and March 2023, which were primarily built for E10 compatibility.

From April 2023 onwards, manufacturers began producing vehicles that are “E20 material compliant,” meaning they are designed to handle petrol blended with up to 20% ethanol. Looking ahead, vehicles sold from April 2025 are expected to be fully E20 compliant, marking a significant shift in India’s automotive ecosystem.

Despite these advancements, experts involved in the policy discussions caution that moving beyond E20 will require both technological upgrades and supportive policy measures. Without these, consumers could face reduced fuel efficiency and potential long-term wear-and-tear issues.

The automobile industry has also raised concerns. Industry body SIAM has suggested tax incentives on E10 and E20 fuels to offset the marginal drop in fuel efficiency experienced by consumers. So far, however, the government has not introduced any such relief.

Meanwhile, signals from policymakers indicate that the ethanol push is only set to intensify. In recent consultations on future fuel efficiency norms, officials from both the power and petroleum ministries have urged automakers to prepare for higher blending levels. Petroleum ministry joint secretary Sujata Sharma recently reinforced this direction, stating that increasing ethanol blending is “an idea whose time has arrived,” with stakeholder consultations currently underway.

Globally, countries like Brazil offer potential models for smoother adoption. As per experts, TOI reported, India could introduce separate fuel dispensers for different ethanol blends, allowing consumers to choose based on vehicle compatibility. Another long-term solution being explored is the promotion of Flex Fuel Vehicles (FFVs), which can run on ethanol blends ranging up to 100%.

In fact, the government is now preparing to notify updated testing norms to enable commercial production of such vehicles. While draft regulations for vehicles capable of running on E85 and higher blends (E100) have been under discussion, final approval is still pending. Although several automakers have developed FFV prototypes, mass-market rollout has yet to begin.