NEW DELHI: The Union oil ministry on Tuesday rejected social media claims that 20% ethanol-blended petrol (E20) causes a drastic drop in fuel efficiency, saying it actually improves acceleration and does not affect vehicle insurance validity. The national programme, blending ethanol from sugarcane or maize with petrol, is aimed at cutting emissions and boosting farmer income. The ministry said some were trying to derail it by misinterpreting an insurance company’s tweet to spread fear. While ethanol has a lower energy density than petrol, resulting in slightly lower mileage, the ministry cited only a marginal drop – 1-2% for vehicles designed for E10 and calibrated for E20, and 3-6% for others. Critics argue ethanol’s calorific value means it produces 65% of petrol’s energy per litre. Currently, most petrol sold is E10, containing 10% ethanol.