Government of India has mandated nationwide sale of E20 petrol (20% ethanol blending) with a minimum Research Octane Number (RON) of 95 across all States and Union Territories from 1 April 2026.
The Centre may grant temporary exemptions for specific regions under special circumstances. This move marks a major milestone in India’s fuel diversification and clean energy transition strategy.
What is E20 Petrol?
E20 petrol contains:
- 80% conventional petrol
- 20% ethanol (biofuel derived from sugarcane, maize, and grains)
Ethanol is:
- Renewable
- Domestically produced
- Cleaner burning than pure petrol
India has already achieved 20% ethanol blending in 2025- five years ahead of the original 2030 target under the National Policy on Biofuels.
Why Minimum RON 95 is Mandatory?
The government has insisted on minimum RON 95 to prevent engine knocking and avoid potential engine damage.
What is RON (Research Octane Number)?
RON measures a fuel’s resistance to knocking (pre-ignition).
Knocking occurs when:
- Fuel burns unevenly
- Causes pinging sound
- Reduces engine power
- May damage engine components over time
Higher RON = Better resistance to knocking.
Ethanol naturally has:
- ~108 RON
- Petrol typically ~84 RON
Blending 20% ethanol increases knock resistance, making fuel suitable for high-compression modern engines. In simple terms, octane reflects a fuel’s ability to remain stable under pressure.
Government’s Objectives
The mandate aims to:
- Reduce crude oil imports
- Lower greenhouse gas emissions
- Boost farmer incomes
- Strengthen domestic biofuel production
- Enhance fuel security
Since 2014-15, India has saved over ₹1.40 lakh crore in foreign exchange through petrol substitution (as per Oil Ministry).
Impact on Vehicles
Compatibility
- Most vehicles manufactured between 2023–2025 are E20-compliant.
- Majority of modern engines are calibrated for ethanol blends.
Observed Concerns
Some older vehicle users report:
- 3–7% mileage drop
- Faster wear of rubber/plastic components
However, industry experts expect the transition to be largely smooth.
Performance Characteristics of E20
Studies and evaluations (including by NITI Aayog, IOCL, ARAI and SIAM) found:
- Improved acceleration
- Smoother driving performance
- Higher knock resistance
- Roughly 30% lower carbon emissions compared to E10 fuel
Ethanol’s higher heat of vaporisation:
- Lowers intake manifold temperature
- Increases air-fuel mixture density
- Enhances volumetric efficiency
Emissions Impact (Life-Cycle Assessment)
A life-cycle emissions study by NITI Aayog found:
- Sugarcane ethanol: ~65% lower greenhouse gas emissions than petrol
- Maize ethanol: ~50% lower emissions than petrol
However, environmental benefits require deeper scrutiny due to agricultural sustainability concerns.
Ethanol Blending Progress in India
- 2014: 1.5% blending
- June 2022: 10% blending achieved ahead of schedule
- 2025: 20% blending achieved
- Target advanced from 2030 to 2025–26
Sugarcane-based ethanol supply:
- FY14: 40 crore litres
- FY24: ~670 crore litres
- Derived from ~9% of total sugar output
The government reports payment of over ₹1.20 lakh crore to farmers since FY15.
Agricultural and Environmental Concerns
While ethanol blending supports farmers, concerns remain:
Water Intensity of Sugarcane
- 60–70 tonnes of water required per tonne of sugarcane
- Optimal rainfall needed: 1,500–3,000 mm
- Many regions fall short of this
This leads to:
- Groundwater over-extraction
- Unsustainable irrigation practices
A 2023 Central Groundwater Board report highlighted:
- Sugarcane-growing districts in Maharashtra extract more groundwater than neighbouring areas.
Land Degradation
The Desertification and Land Degradation Atlas of India 2021 found:
- Nearly 30% of India’s land is degraded.
Water-intensive cropping combined with climate variability may worsen ecological stress. Thus, while ethanol reduces fossil fuel emissions, agricultural sustainability remains a critical policy issue.
Policy and Institutional Framework
The ethanol blending push is aligned with:
- National Policy on Biofuels
- Energy security goals
- Farmer income enhancement strategy
- Climate commitments under India’s NDCs
Technical evaluations were conducted by:
- Indian Oil Corporation Limited
- Automotive Research Association of India
- Society of Indian Automobile Manufacturers
Economic Impact
Benefits
- Reduced oil import dependency
- Foreign exchange savings
- Stable demand for sugarcane and maize
- Farmer income support
- Rural industrialisation
Risks
- Overdependence on water-intensive crops
- Groundwater depletion
- Land degradation
- Food vs fuel concerns
- Regional ecological imbalance
Strategic Significance
The E20 mandate represents:
- A structural shift in India’s fuel policy
- Movement towards biofuel-led energy diversification
- A balancing act between energy security and environmental sustainability
- Acceleration of India’s clean mobility transition
However, long-term success will depend on:
- Diversification beyond sugarcane (e.g., grain-based, 2G ethanol)
- Sustainable water management
- Crop pattern rationalisation
- Continued engine calibration improvements