Ethanol-Blended Fuel Optimization for Improving Efficiency and Reducing Emissions in Indian Commercial Trucks

This manuscript examines ethanol-assisted decarbonization pathways for Indian commercial trucks and reframes the problem around the technical realities of heavy-duty compression-ignition engines. While national policy discourse on ethanol in India has focused primarily on spark-ignition gasoline applications, the freight sector remains dominated by diesel platforms whose fuel economy, duty cycles, durability expectations, and aftertreatment constraints differ markedly from passenger vehicles. The paper therefore evaluates ethanol deployment for trucks through two technically credible routes: low-level stabilized ethanol–diesel blends and ethanol–diesel dual-fuel operation in which diesel remains the ignition source and ethanol supplies a controlled share of the total fuel energy. To bridge the gap between laboratory evidence and field-retrofit feasibility, a Retrofit Ethanol Assist Module (REAM) is proposed as a supervisory add-on that estimates ethanol fraction, schedules injection corrections, applies combustion-safety guard rails, and preserves aftertreatment functionality. The paper synthesizes findings from peer-reviewed studies on fuel stability, lubricity, ignition delay, low-temperature combustion, reactivity-controlled compression ignition, heavy-duty dual-fuel operation, and fuel consumption modeling. The analysis shows that ethanol can substantially reduce soot, carbon monoxide, and unburned hydrocarbon emissions, and under optimized medium-to-high-load operation can lower nitrogen oxides while maintaining or slightly improving indicated efficiency. The revised contribution is therefore a literature-grounded engineering framework that converts scattered results into a coherent retrofit architecture and validation methodology suitable for future experimental work and conference extension.