According to reports citing Bhutan’s Department of Trade, the Himalayan nation has opted not to import India’s newly rolled-out E20 petrol (a blend of 20% ethanol and 80% gasoline) and has requested Indian Oil Marketing Companies (OMCs) to continue supplying conventional unleaded petrol for as long as it remains available in India. The decision stems from two primary challenges tied directly to the country’s high-altitude environment and aging fuel handling systems.
First, ethanol is highly hygroscopic—meaning it readily absorbs water from the air. In Bhutan’s humid, mountain climate, aging underground storage tanks and distribution depots face significant risks of water seepage, which can cause phase separation in E20 fuel, resulting in engine damage, component corrosion, and breakdown in remote areas. Second, Bhutanese officials expressed concerns regarding engine performance on steep mountain gradients, where vehicles require maximum power and consistent fuel quality that ethanol blends may struggle to deliver compared to unblended petrol.