Context:

• The controversy over E20 petrol (20% ethanol blending) has largely focused on claims that it damages engines and significantly reduces mileage.
• While evidence does not substantiate widespread engine damage, the controversy exposes a more important policy question: how far should India expand ethanol blending?
• This question is more significant given ethanol blending’s implications for food security, water use, farm incomes, energy security and the environment.

E20 and Engine Concerns - Separating Fact from Fear:

• Ethanol contains roughly two-thirds the energy of petrol. Since E20 contains only one-fifth ethanol, the expected energy-related reduction in mileage is around 6–7%, not the exaggerated 30% often circulated online.
• E20 can also reduce carbon monoxide and unburnt hydrocarbon emissions, offering environmental benefits.
• Evidence on engine durability is broadly reassuring. For example,
  • Oak Ridge National Laboratory tested 86 vehicles over nearly 10 million km using blends up to E20 and found no increased wear in vehicles not rated for E20.
  • Indian testing by ARAI, the Petroleum Institute and Indian Oil similarly did not establish widespread engine damage.
• Genuine vulnerability - Older two-wheelers:
  • The important exception is India's estimated 75–80 million pre-BS4 two-wheelers, many of which use carburettors.
  • These cannot automatically adjust to the additional oxygen in ethanol blends, potentially causing lean combustion and overheating. Older ethanol-incompatible rubber seals may also deteriorate.
  • The original policy roadmap envisaged retaining a lower ethanol blend for such vehicles.
  • Restoring E10 alongside E20 could protect the legacy fleet while allowing gradual retrofitting.

The Bigger Question - Should Blending Go Beyond E20?

• The real policy dilemma begins with proposals for E27/E30. Higher blending could increasingly shift agricultural resources from food towards fuel.
• India's annual crude oil import bill is around ₹11–12 lakh crore, while the edible oil import bill is approximately ₹1.6–1.75 lakh crore.
• E20 reduces the crude oil bill by only about 3–4%, whereas edible-oil self-sufficiency offers a potentially more achievable reduction in import dependence.
• India currently produces only around 40% of its edible oil requirement and aims to raise domestic production substantially by 2030–31.

Maize and the Food-vs-Fuel Trade-off:

• The ethanol feedstock structure has changed significantly. For example, maize accounts for about half of ethanol production, and grains collectively contribute nearly 67%.
• Maize competes with soybean, groundnut and mustard for agricultural land.
• Policy incentives intensify this competition because ethanol procurement prices can make maize attractive irrespective of market conditions.
• Distillation by-products are also sold as animal feed, potentially weakening demand and prices for soybean meal.
• Thus, oilseed farmers may face a double disadvantage through both land competition and weaker oilseed prices.

Water Security - Focus on Blue Water:

• Water consumption must be assessed carefully. Headline claims about thousands of litres of water per litre of ethanol often combine:
  • Green water — rainfall naturally received by crops.
  • Blue water — water drawn from rivers, canals, groundwater and wells.
• For water-stressed regions, particularly parts of Maharashtra and Karnataka, policy should primarily regulate blue-water consumption, since it directly competes with other human and ecological requirements.

Is More Ethanol Necessarily Greener?

• The environmental case for moving beyond E20 is not conclusive.
• Higher blending would rely substantially on grain-based ethanol, while Indian life-cycle assessments differ on whether grain ethanol delivers significant climate benefits after accounting for cultivation, processing and associated inputs.
• Therefore, the green argument for higher blending requires stronger scientific scrutiny, rather than being treated as self-evident.

Gains and Costs of the Ethanol Programme:

• Ethanol blending has produced significant benefits -
  • Helped clear sugarcane arrears.
  • Created an assured market for farmers.
  • Supported rural incomes.
  • Enabled distilleries to utilise surplus sugar.
  • Reduced some dependence on imported fossil fuels.
• However, remaining at E20 also has costs. For example,
  • Distilleries have invested in capacity based on expectations of higher ethanol demand,
  • While loans and the management of sugar surpluses are increasingly linked to the ethanol programme.
• Hence, both the benefits of expansion and the costs of stopping at E20 must enter the policy calculus.

Policy Principle - Prioritise Reversible Decisions:

• The most important policy insight is the distinction between reversible and irreversible interventions.
• Measures such as ethanol procurement prices, lower-blend “protection fuel”, water-use regulations, and edible-oil import duties can be modified relatively quickly.
• In contrast, once agricultural land and water are committed to fuel production, and cropping patterns and distillery capacity are established, reversing the policy becomes difficult and costly.
• Therefore, India should adopt a precautionary, evidence-based approach before increasing the mandatory blend beyond E20.

Way Forward:

• Restore E10 or another lower blend for the older vehicle fleet.
• Correct pricing incentives that disproportionately favour maize over oilseeds.
• Regulate ethanol production based on blue-water availability in water-stressed regions.
• Reassess edible-oil import duties and agricultural incentives to promote domestic oilseed production.
• Undertake a comprehensive food-versus-fuel cost-benefit analysis before moving beyond E20.
• Continue scientific assessment of ethanol's life-cycle emissions and water footprint.

Conclusion:

• The E20 controversy should not be reduced to a question of engine damage or mileage.
• The deeper issue is whether India should commit scarce land, water and agricultural resources to progressively higher fuel blending when the gains in energy security remain modest and some consequences may be difficult to reverse.