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Journal of Petroleum Engineering & Technology Research Article

Sustainable Chemistry for Climate Action-E-20 Ethanol-Blended Petrol in India: A Comprehensive Assessment of Energy Security, Environmental Sustainability, Economic Benefits, and Human Health

  1. Ravuri Hema Krishna ✉ Professor, Professor, Department of Chemistry, Amrita Sai Institute of Science and Technology, Bathinapadu, Andhra Pradesh, India

Abstract

The transition from conventional petrol to ethanol-blended petrol represents an important component of India’s strategy to strengthen energy security, reduce dependence on imported fossil fuels, promote renewable energy, and support sustainable transportation. Among the available ethanol blends, E20 petrol, comprising approximately 20% ethanol and 80% petrol by volume, has emerged as a major milestone in India’s Ethanol Blended Petrol (EBP) Programme. India reached its 20% ethanol-blending goal during the 2025–26 Ethanol Supply Year, achieving the milestone several years ahead of the initially planned 2030 deadline. The increased adoption of E20 has important implications for the country’s economy, agriculture, energy security, environment, and public health. Replacement of a portion of petroleum-derived fuel with domestically produced ethanol can reduce crude-oil import requirements, conserve foreign exchange, enhance domestic energy resilience, and create additional markets for agricultural feedstocks such as sugarcane and maize. Ethanol’s high-octane number and oxygenated molecular structure can also influence engine combustion and exhaust emissions. Available assessments indicate that ethanol blending can reduce selected pollutants, particularly carbon monoxide and hydrocarbons, although changes in nitrogen oxides and other emissions depend on engine technology, fuel formulation, operating conditions, and vehicle characteristics. Lifecycle assessments further indicate that ethanol produced from suitable Indian feedstocks can have substantially lower greenhouse-gas emissions than conventional petrol. These environmental benefits may contribute indirectly to improved air quality and reduced exposure to certain traffic-related pollutants, thereby providing potential public-health advantages. However, the sustainability of E20 depends on feedstock selection, agricultural practices, water and land requirements, production efficiency, lifecycle emissions, and vehicle compatibility. This review critically examines the economic, energy-security, environmental, agricultural, and human-health implications of E20 compared with conventional petrol and evaluates its opportunities, limitations, and future prospects for sustainable transportation in India.

Keywords

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