Stimulation of ethanol-blending and emission standards to combat vehicular pollution in India

Vehicular polluter is one of the major contributors to air pollution. Emission norms and shifting to clean fuels are the major policy directions in achieving the vehicular emission reduction. In India, Bharat Stage Emission Standards have been implemented to reduce the vehicle exhaust emissions, alongside the promotion of alternative fuels. Further, the use of adopting clean fuels remains a practical and effective approach to reduce vehicular emissions. In the present study, the impact of the use of ethanol-blended fuel and the co-benefit of emission standards on vehicular emissions is assessed and compared with the emissions from petrol, diesel and CNG vehicles. The analysis reveals that CO and PM_2.5 emissions are unavoidable from the ethanol-blended vehicles, but the NO_x emissions are controlled irrespective of the BS norms. Ethanol-blending and CNG fuels show comparatively lesser emissions than the other fuels. The findings indicate that ethanol may be a good renewable fuel choice for cutting emissions without having to eliminate vehicles right once. An affordable way to move toward cleaner mobility would be to combine ethanol and retrofit older BS-III and BS-IV vehicles with cutting-edge aftertreatment technology seen in BS-VI engines. Norms like the EURO-VII plan, which imposes consistent emission limitations on various fuel types, are in line with fuel- and technology-neutral policies. The study calls for an integrated approach of ‘clean fuels’ and ‘clean technologies’ to achieve vehicle emission reduction targets.