E100 and B100: Draft Rule Change to Allow 100% Biofuels
Why in the news
A draft rule change would move biofuels from blending additives to standalone fuels for vehicles.
Key facts
- Law: draft amendment to the Central Motor Vehicle Rules, 1989.
- E100: pure anhydrous ethanol, requiring Flex-Fuel Vehicles or dedicated engines.
- B100: neat biodiesel from vegetable oils, animal fats or used cooking oil by transesterification.
- Forex saved: $19.3 billion by January 2026.
- Farmer payments: over $15 billion in a decade, for ethanol feedstocks like sugarcane and grain.
| Fuel | Current wording | Proposed wording |
|---|---|---|
| Ethanol | E85 | E85 or E100 |
| Biodiesel | B10 | B100 |
Significance
- Energy sovereignty: lower crude import bill amid West Asia volatility.
- Forex savings from the ethanol programme.
- Farm support: payments to sugarcane and grain growers.
Brazil model
Brazil has had flex-fuel vehicles since 2003, and 90% of new sales are FFVs, letting buyers choose petrol or ethanol at the pump based on price.
Concerns
E20 drew consumer complaints in 2025 over lower mileage, since ethanol has less energy density, and possible corrosion of rubber and plastic parts in older engines; E100 and B100 will likely need optimised engines.
Exam angle
- Rules amended: Central Motor Vehicle Rules, 1989.
- Reference country: Brazil.
- Ethanol Supply Year: November to October.