In this direction, the successful experience of ethanol implementation in Brazil – which in 2020 replaced 48% of its petrol with ethanol – could provide India a pointer. This has been achieved through the mixture of 27% anhydrous ethanol in gasoline and the use of pure ethanol by a ‘flex fleet’, which represents more than 86% of the total vehicle fleet. In Brazil, ethanol is sold in a network of more than 41,700 retail outlets. So, while many countries opt for electrification in mobility, ethanol’s role in sustainable mobility should be considered.
Electrification is a trend because energy consumption of electric motors is lower, at about 0.7 MJ/km, compared to vehicles equipped with internal combustion engines (ICE), at 1.62 MJ/km. The problem begins when electrification is thought to be synonymous with one of its options: battery-powered electric vehicle (BEV). There are other electrification options, such as parallel and in-series hybrids, and vehicles equipped with fuel cells, with or without on-board reform, or extraction of hydrogen. Hybrids and fuel cells with on-board reforming operate on liquid fuels. The cleaner or more renewable these fuels are, the more sustainable the solution will be.
The most appropriate combination of motorisation and transport energy will depend on the geography and characteristics of each country or region. The option to be adopted will depend on how public policy will be measuring the energy and environmental impacts. If public policy is interested in measuring only exhaust emissions, the battery-powered vehicle can be considered a solution, even using electricity produced from a fossil source. This is the ‘tank-to-wheel’ concept, admittedly partial and incomplete.
If the policy assesses related emissions from energy generation to its final use, we will have a more complete ‘well-to-wheel’ assessment. If the policy assesses full emissions including those related to the construction and disposal of vehicles and power-generation systems, it will follow the ‘cradle-to-grave’ concept.
Some emission-control strategies have been based on engines without, however, worrying about the source of energy. In Europe and the US, under the ‘well-to-wheel’ concept, petrol or diesel vehicles emit 122-150 gm of CO2-equivalent/km (gCO2e/km). BEVs in Europe, however, emit about 92 gCO2e/km using the average local fossil-renewable electricity mix. Reducing emissions from 122 to 92 gCO2e/km is an advance, despite the high cost of the vehicle and new infrastructure required.
But this level of emissions is still far above the 58 gCO2e/km emitted by ethanol-fuelled ICEs of the flex fleet in Brazil, and the 29 gCO2e/km of flex ethanol hybrids being sold there since September 2019. By 2032, BEVs are expected to be emitting 74 gCO2/km, ethanol ICE vehicles down to 38 gCO2e/km, and ethanol hybrids 27 gCO2e/km, the same level as ethanol fuel cells, all under ‘well-to-wheel’. In the cradle-to-grave concept, the advantage of ethanol-powered engines is even greater.
Several countries follow the Brazilian example. Others are unable to produce biofuels in sufficient volume due to the limitations of land, sun and water. Some have announced plans to expand wind and solar photovoltaic generation – intermittent sources of energy – storing them in the form of hydrogen generated from electrolysis of water. But this solution presents hurdles in generation, storage and distribution. As hydrogen requires storage in expensive and risky 500-900 bar pressure tanks, it is more suitable for expansion into stationary units for ammonia production and other industrial applications only.
For distribution in a disperse geography where there are production conditions for such, ethanol and biogas, and biomethane generated from agro-industrial waste, it should be understood as enveloped hydrogen in the form of liquid fuel, captured, stored and distributed in an efficient, economical and safe manner. Sustainably produced biofuels, such as ethanol and biomethane, allow many countries to enter the Age of Hydrogen.
As India intensifies the use of ethanol in mobility, it will not only promote a sustainable source of energy in transport, but will simultaneously address three pressing issues: dependence on oil imports and its impact on the trade balance; diversification and promotion of income and jobs in agriculture using available feedstocks; and the significant reduction in local and global emissions.
The above news was originally posted on economictimes.indiatimes.com
