Ethanol policy must count in water, sustainability costs, Pg15

Key Highlights:

• India's E20 petrol rollout is an ambitious biofuel initiative, with ethanol blending increasing from 1.5% in 2013-14 to nearly 20% in 2025.
• The program has successfully reduced crude oil imports, generated rural incomes, and diversified the country’s energy basket.
• The article highlights concerns about the sustainability of ethanol production, particularly its significant water footprint and varying environmental impact based on feedstock.
• Sugarcane, a primary feedstock for ethanol, is highly water-intensive, requiring 1,500–2,500 mm of water per growing season.
• Policy decisions for ethanol blending should be guided by scientific evidence and sound public economics rather than solely by blending targets.

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Detailed Insights:

• Ethanol is produced from various feedstocks including C-heavy molasses, B-heavy molasses, sugarcane juice, maize, and damaged food grains, each with a different environmental footprint.
• The Energy Return on Energy Invested (EROEI) for sugarcane ethanol is typically 2-4, while grain-based ethanol ranges from 1.2-2, indicating varying energy efficiency.
• E20 fuel contains 6-7% less energy than pure petrol, potentially reducing fuel economy, though higher octane can offset this in calibrated engines.
• Vehicles manufactured from April 2023 are mandated to be E20 compatible, but older vehicles require continued availability of lower-blend fuels and consumer information.
• Climate benefits of ethanol must be assessed through a life-cycle assessment, considering emissions from cultivation, processing, and transport, as it is not inherently carbon neutral.
• Producing one litre of sugarcane ethanol can embody 2,000–3,500 litres of water, posing a significant challenge in India's water-stressed regions.
• Subsidies for electricity and urea encourage unsustainable practices like excessive groundwater extraction and overuse of nitrogen fertilizers in sugarcane cultivation.
• The article suggests reforming subsidies to support farmers directly through income transfers and allowing market-reflective pricing for resources.
• Investment in second-generation ethanol derived from agricultural residues and non-food biomass is crucial to reduce pressure on land and water resources.

Key Concepts Involved:

• E20 petrol: A motor fuel blend consisting of 20% ethanol and 80% gasoline.
• Energy Return on Energy Invested (EROEI): A ratio that compares the amount of energy delivered by a system to the amount of energy consumed to deliver that energy.
• Life-cycle assessment: A comprehensive method to evaluate the environmental impacts of a product or system throughout its entire life cycle, from raw material extraction to disposal.
• Second-generation ethanol: Biofuel produced from non-food biomass sources such as agricultural residues, wood, or dedicated energy crops.