Ethanol is a renewable, domestically produced transportation fuel. Ethanol is produced by fermentation of waste plant material i.e. biomass. Ethanol is an organic chemical compound. It is simple alcohol with the chemical formula C2HSOH, and is often abbreviated as EtOH. Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor. Ethanol is also produced via petrochemical processes such as ethylene hydration. Ethanol is also listed as a biofuel as the source of the fuel is biological in origin. The most common ethanol production processes today use yeast to ferment the starch and sugars in corn or sugar cane or sugar beets. Corn is the main feedstock for fuel ethanol in the United States because of its abundance and relatively low price historically. The starch in corn kernels is fermented into sugar, which is then fermented into alcohol. In India ethanol is produced as a by product in the sugar production process during fermentation of sugarcane juice by yeasts.
Ethanol (Biofuel) Generations
India released the biofuel policy document in 2018. As per the national policy and in alignment with international practice biofuels are categorised in four generations as shown in Figure 1.
1G Ethanol is the traditional ethanol produce from sources such as sugarcane and corn. The production is from edible food stocks and fueled the Food Vs Fuel debate. So also the agricultural land utilization and higher water use for growing sugarcane was highlighted as concerns. 2G Ethanol seeks to use waste biomass to generate ethanol from cellulose.
Use of rice husks, straw or waste wood chips which were traditionally burned by farmers causing air pollution can be used for ethanol fuel generation. 3G Ethanol does not require any land resource at all and is generated from extracts from Algae which grow on waste water ponds or artificial lakes. 4G Ethanol is produced from genetically engineered crops using advances in biotechnology which absorb carbon from the atmosphere and hence are termed carbon negative. In India 1G ethanol is widely available and 2G ethanol production has commenced with encouragement from the Government.
Experimental work on 3G Ethanol is in progress in India in some premier biotechnology research institutions.
Global Use of Ethanol as a Vehicular Fuel
Ethanol is an ideal fuel for vehicles using spark ignited engines such as 2 Wheelers, 3 Wheelers, Passenger Cars, SUVs and small commercial vehicles. Ethanol has good miscibility with gasoline and can be blended easily with some additives. The common blends of ethanol-gasoline in India are 5% ethanol blend (E5) and 10% ethanol blend (E10). In countries like USA 15% ethanol blend (E15) and 20% ethanol blends (E20) are in use. India also notified E12, E15 and E20 as ethanol blends for future. Brazil allows 25% ethanol blend (E25) and 27% ethanol blend (E27) as well. The ethanol blends higher than 20% till 85% can be used in a special category of vehicles known as flex-fuel vehicles (FFV). The consumer is free to fill any blend of ethanol as per availability in the vehicle fuel tank. The FFVs have the ability to detect the percentage of ethanol in the fuel tank through sensors and can adjust the engine operation parameters including the ignition timing and air fuel ratio through the electronic control unit. Such FFVs are widely used in countries like Brazil, Europe and USA. India is expected to announce a policy for introduction of ethanol vehicles soon. Figure 2 summarises the ethanol fuel blends.
The neat ethanol vehicles used in countries like Brazil are termed as E100 vehicles. The actual percentage of ethanol is neat ethanol vehicles is 93% (E93) with 7% additives. There is also a category of vehicles such as buses and trucks which use compression ignition engines fueled by 95% ethanol with 5% ignition additives (ED 95). This technology is used in Europe and some buses were introduced in India.
Emission Benefits of Ethanol Blending in Gasoline
When blended with gasoline for use as a vehicle fuel, ethanol can offer some emissions benefits depending on vehicle type, engine calibration, and blend level. As with conventional fuels, the use and storage of ethanol blends can result in emissions of regulated pollutants, toxic chemicals, and greenhouse gases (GHGs). Adding ethanol to gasoline even in low percentages, such as 10% ethanol and 90% gasoline (E10), reduces carbon monoxide emissions from the gasoline and improves fuel octane. Using ethanol as a vehicle fuel has measurable GHG emissions benefits when considering the life cycle steps required for gasoline. Carbon dioxide (CO2) released when ethanol is used in vehicles is offset by the CO2 captured when crops used to make the ethanol are grown. As a result, FFVs running on high-level blends of ethanol produce less net CO2 than conventional vehicles per mile traveled.
A life cycle analysis was published by USDOE in 2018. Figure 3 shows the results of the LCA. It projected the reduction in carbon intensity of emissions arising from transport and other sources. The baseline was taken as 2005 with a predominant gasoline mobility resulting in 98000 grams of CO2 emissions/MMBtu energy produced in USA. Due to implementation of ethanol blending (produced from corn) and introduction of flex fuel vehicles as well as resultant changes in agriculture and crude oil refining the CO2 emissions decreased to 59,766 g/MMBtu. The report also develops two projected emission profiles for corn ethanol in 2022. The first scenario is business-as-usual (BAU) scenario, assumes that recent trends observed in corn inputs, per-acre corn yields, refinery technologies, vehicle fleets, and other factors continue through 2022. The continuation of these trends has implications for the path that GHG emissions attributable to corn ethanol production will reduce to 54,588 g CO2/ MMBtu. The second projection, labeled the High Efficiency-High Conservation (HEHC) scenario is based on the assumption that refineries adopt a set of currently available technologies and practices that are known to reduce emissions in corn production, ethanol refining, transportation, and co-product management. The HEHC scenario can be viewed as a case where refineries take a more aggressive approach to reducing emissions. This results in the lowest levels of 27852 g CO2/ MMBtu emissions.
Disadvantages of Ethanol Blending in Gasoline
Because low levels of ethanol can cause gasoline to evaporate more easily, low-level ethanol blends can increase evaporative emissions in gasoline vehicles. However, vapor pressure for low-level ethanol blends can be adjusted to adhere to the same volatility standards as gasoline. A gallon of ethanol contains less energy than a gallon of gasoline, resulting in lower fuel economy when operating the vehicle. The impact to fuel economy varies depending on the energy difference in the blend used. For example, E85 that contains 83% ethanol content has about 27% less energy per gallon than gasoline (the impact to fuel economy lessens as ethanol content decreases). Engines in gasoline vehicles, including flexible-fuel vehicles (FFVs), are optimised for gasoline. If they were optimised to run on higher ethanol blends, fuel economy would likely increase as a result of increased engine efficiency.
Case Study of Brazil as a Success Story of Ethanol Blending
Brazil is the world’s second largest producer of ethanol fuel following the United States. Brazil and the United States have led the industrial production of ethanol fuel for several years, together accounting for 85 percent of the world’s production in 2017. Brazil produced 26.72 billion liters representing 26.1 percent of the world’s total ethanol used as fuel in 2017. Between 2006 and 2008, Brazil was considered to have the world’s first “sustainable” biofuels economy and the biofuel industry leader a policy model for other countries; and its sugarcane ethanol “the most successful alternative fuel to date. Brazil’s 40-yearold ethanol fuel program is based on the most efficient agricultural technology for sugarcane cultivation in the world, uses modern equipment and cheap sugar cane as feedstock, the residual cane-waste (bagasse) is used to produce heat and power, which results in a very competitive price. Brazilian sugarcane based ethanol programme resulted in 61% reduction of total life cycle greenhouse gas emissions, including direct indirect land use change emissions.
Since 1976, the Brazilian government made it mandatory to blend anhydrous ethanol with gasoline, fluctuating between 10% to 22% which required minor adjustments in gasoline engines. In 1993 the mandatory blend was fixed by law at 22% anhydrous ethanol (E22) by volume in the entire country, but with leeway to the Executive to set different percentages of ethanol within pre-established boundaries. In 2003 these limits were set at a minimum of 20% and a maximum of 25%.
Since July 1, 2007 the mandatory blend is 25% of anhydrous ethanol (E25) and 75% gasoline. The lower limit was reduced to 18% in April 2011 due to recurring ethanol supply shortages and high ethanol prices between harvest seasons. By mid March 2015 the government raised temporarily the ethanol blend in regular gasoline from 25% to 27%. Figure 4 shows the historic progression of ethanol blending in Brazil.
Brazil has ethanol fuel available throughout the country. There are no longer any light vehicles in Brazil running on pure gasoline. Figure 5 shows a typical Petrobras gas station at São Paulo with dual fuel service, marked A for alcohol (ethanol) and G for gasoline.
The Brazilian car manufacturing industry developed flexible-fuel vehicles that can run on any proportion of gasoline (E20-E25 blend) and hydrous ethanol (E100). Introduced in the market in 2003, flex vehicles became a commercial success, dominating the passenger vehicle market with a 94% market share of all new cars and light vehicles sold in 2013. By mid-2010 there were 70 flex models available in the market including sports cars, off-road vehicles and minivans. As of June 2015, flex-fuel light-duty vehicle cumulative sales totaled 25.5 million units, and production of flex motorcycles totaled 4 million. The success of “flex” vehicles, together with the mandatory E25 blend throughout the country, allowed ethanol fuel consumption in the country to achieve a 50% market share of the gasoline-powered fleet.
Status of Ethanol Blending in India
The ethanol blending programme started in 2003 where 5% ethanol blending was mandated in 9 states and four union territories. In 2006 the 5% blend and in 2008 the 10% blend was mandated for the entire country. The ethanol blending was not uniform in India as some places E0 was supplied, whereas some other places E5 nr E10 was available. The average ethanol blending percentage in 2017 was only 2.3%, which continued to rise to 4.6% in 2019 to 8.1% in 2021. It is expected that India will have E10 all over the country by 2022 and E20 will be introduced from 2023 to 2025 five years ahead of the biofuel policy deadline of 2030. Figure 6 summarises the timeline for the ethanol blending programme in India.
E20 Launch by Hon’ble PM of India
According to the report, 20% ethanol blending is within reach. The report further lays out an annual plan for the gradual rollout of E20 ethanol in the country. It suggests specific responsibilities of Union Ministries, State Governments and vehicle manufacturers for the production, supply and gradual rollout of 20% ethanol blending in petrol by 2025. Immense benefits can accrue to the country by 20% ethanol blending by 2025, such as saving Rs 30,000 crore of foreign exchange per year, energy security, lower carbon emissions, better air quality, self reliance, use of damaged food-grains, increasing farmers’ incomes, employment generation and greater investment opportunities. The E-20 roadmap proposes the following milestones:
- Raise pan-India ethanol production capacity from the current 700 to 1500 crore litres
- Phased rollout of E10 fuel by April 2022
- Phased rollout of E20 from April 2023, its availability by April 2025
- Rollout of E20 material-compliant and E10 engine-tuned vehicles from April 2023
- Production of E20-tuned engine vehicles from April 2025
- Nationwide educational campaign
- Encourage use of water-sparing crops, such as maize, to produce ethanol
- Promote technology for the production of ethanol from non-food feedstock
Other recommendations include expediting regulatory clearances for ethanol distilleries through a single-window mechanism, unrestricted movement of denatured ethanol all over the country, tax incentives for blended fuel and petrol vehicles.
Ethanol production – National Biofuel Policy (2018)
Government of India has emphasized on achieving energy security of the country with a target of reducing import dependence i.e. usage of fossil fuels by 10% from 2014-15 levels by the year 2022. This target is to be achieved by adopting a five pronged strategy which includes, Increasing Domestic Production, Adopting Biofuels and Renewable, Energy Efficiency Norms, Improvement in Refinery Processes and Demand Substitution. This envisages a strategic role for biofuels in the Indian Energy basket. The growing concern about the import dependence for fuel requirement in tandem with environmental pollution issues have driven the need for biofuels that have superior environment benefits and are economically competitive with fossil fuels. Figure 7 highlights the Vision of national biofuel policy of 2018.
The Salient Features of the policy are:
- The Policy categorises biofuels as First Generation (1G) bioethanol & biodiesel and “Advanced Biofuels” – Second Generation (2G) ethanol, Third Generation (3G) biofuels, to enable extension of appropriate financial and fiscal incentives under each category.
- The Policy expands the scope of raw material for ethanol production by allowing use of Sugarcane Juice, Sugar containing materials like Sugar Beet, Sweet Sorghum, Starch containing materials like Corn, Cassava, Damaged food grains like wheat, broken rice, Rotten Potatoes, unfit for human consumption for ethanol production.
- Farmers are at a risk of not getting appropriate price for their produce during the surplus production phase. Taking this into account, the Policy allows use of surplus food grains for production of ethanol for blending with petrol with the approval of National Biofuel Coordination Committee.
- With a thrust on Advanced Biofuels, the Policy indicates a viability gap funding scheme for 2G ethanol Bio refineries of Rs 5000 crore in 6 years in addition to additional tax incentives, higher purchase price as compared to 1G biofuels.
- The Policy encourages setting up of supply chain mechanisms for biodiesel production from non-edible oilseeds, Used Cooking Oil, short gestation crops.
- Roles and responsibilities of all the concerned Ministries/Departments with respect to biofuels has been captured in the Policy document to synergise efforts.
Review of CMVR Regulations on Ethanol
Ethanol has been notified as an automotive fuel in the central motor vehicle rules (CMVR) through notifications released by the Ministry of Road Transport and Highways. Each notification has a unique GSR number and contains information on effective date of implementation, the applicability of fuel to various vehicle categories, reference to fuel quality standards published by BIS, emission testing methodology and emission limits applicable. The following are the notifications published till date.
- GSR 682 (2016) – For notification of Flex Fuel Vehicles (E85) + Compression ignition Ethanol technology vehicles (ED 95) + Pure Ethanol Vehicles (E100).
- GSR 156 (2021) – For notification of 20% Ethanol Gasoline blend (E20) for use in vehicles powered by spark ignited engines.
- GSR 439 (2021) – For notification of 12% Ethanol Gasoline blend (E12) and 15% Ethanol Gasoline blend (E15) for use in vehicles powered by spark ignited engines.
Review of BIS Standards on Ethanol
BIS is the authority which frames the national standards for India. BIS standards for fuel specifications are drafted by the Petroleum and Chemicals division (PCD 3) committee. The standards include information on the fuel, the specifications of the fuel including limits and testing methodology for fuel characterisation. The standard also provides international references. Following are the BIS standards released by BIS.
- IS 2796 (2008) – This is the standard for commercial Gasoline. Through the control order released by ministry of petroleum this standard was amended to include E5 and subsequently E10.
- IS 17021 (2021) – This is the standard specifying 20% Ethanol Gasoline blend (E20) for use in vehicles powered by spark ignited engines.
- IS 17586 (2021) – This is the standard specifying 12 % Ethanol Gasoline blend (E12) and 15% Ethanol Gasoline blend (E15) for use in vehicles powered by spark ignited engines.
- IS 16634 (2017) – This is the standard specifying 85% Ethanol (E85) for use in flex fuel vehicles powered by spark ignited engines.
- IS 16629 (2017) – This is the standard specifying 95% Ethanol (ED95) and additives for use in vehicles powered by compression ignition engines.
- IS 15464 (2004) – This is the standard specifying 100% Ethanol (E100) for use in vehicles powered by spark ignited engines
Review of AIS 171 – Safety Standard on Ethanol
The AISC committee published the AIS 171 as a safety standard to be followed by ethanol vehicles for safe operation and guidelines for test agencies for type approval of ethanol vehicles. The standard is titled as Safety Requirements for Type Approval of Anhydrous Ethanol & Ethanol Blended Motor Gasoline (EBMG) Vehicles (for Blends ≥ 20%). The standard is applicable for Vehicles using higher than 20% ethanol blends up to 100% ethanol. The lower blends including E-20 have been excluded from the scope as they are treated at par with gasoline. The contents of the standard are as follows:
- Anhydrous Ethanol Fuel Quality Requirements
- Material Compatibility Requirements
- Health Safety Considerations
- Fire Safety Considerations
- Electrical Conductivity Safety Considerations
- Labeling of Ethanol Vehicles
- International References
Flex Fuel Vehicle
Flex fuel vehicles have an internal combustion engine capable of functioning with a variable mixture of ethanol and gasoline. Flex fuel engines are already available in countries such as Brazil, the USA, and Canada. Flexible fuel vehicles (FFVs) have an internal combustion engine and are capable of operating on gasoline and any blend of gasoline and ethanol up to 83%. FFVs have one fuel system, and most components are the same as those found in a conventional gasoline-only car.
Some special ethanol-compatible components are required to compensate for the different chemical properties and energy content in ethanol, such as modifications to the fuel pump and fuel injection system. The engine control module (ECM) is also calibrated to accommodate the higher oxygen content of ethanol. Figure 8 provides the key components of the flex fuel vehicles.
The components of the vehicle include a receptacle to which the nozzle from the dispenser is attached for supply of fuel to the vehicle. Fuel injection system introduces fuel into the engine’s combustion chambers for ignition. The fuel line is metal tube or flexible hose transfers fuel from the tank to the engine’s fuel injection system. A fuel pump transfers fuel from the tank to the engine’s fuel injection system via the fuel line. Fuel tank stores fuel on board the vehicle to power the engine. The fuel is injected into either the intake manifold or the combustion chamber in the engine, where it is combined with air and the mixture is ignited by the spark from a spark plug. The transmission transfers mechanical power from the engine and/or electric traction motor to drive the wheels. The ECM controls the fuel mixture, ignition timing, and emissions system; monitors the operation of the vehicle; safeguards the engine from abuse; and detects and troubleshoots problems. The battery provides electricity to start the engine and power vehicle electronics/accessories. The exhaust system channels the exhaust gases from the engine out through the tailpipe. A three-way catalyst is designed to reduce engine-out emissions within the exhaust system.
Advantage of flex fuel vehicles is that ethanol does not contribute significantly to greenhouse gasses, making it a popular alternative for GHG reduction. Further advantage of the flex fuel vehicle is that it is designed to burn whatever proportion of ethanol blend is available in its combustion chamber. Electronic sensors gauge the blend, while microprocessors adjust the fuel injection and timing. Another significant advantage of driving a flex fuel vehicle is the tax credit which is provided for encouraging green vehicles by the Government. Disadvantage of flex fuel vehicles in that it does not provide the same level of fuel efficiency as equivalent Gasoline Vehicle. Ethanol (E85) will reduce vehicle mileage by 25% to 27% due to lower calorific value of ethanol as compared to Gasoline. Also the availability of flex fuel stations is an impediment in its growth.
Introduction of Flex Fuel vehicles In India
Recently, Hon. Minister of Road Transport Shri. Nitin Gadkari has appealed to the CEOs of Indian Automobile Manufacturers to roll out flex fuel two wheeler and four wheeler vehicles in the Indian market within a year’s time. Auto companies in India may soon be asked to manufacture passenger and commercial vehicles that run on multiple fuel configuration aimed at reducing the use of polluting fossil fuels and cutting down harmful emissions. The government is also working on an incentive scheme to promote manufacture and use of flex engines in vehicles. New policy for use of flexible fuel vehicles (FFVs) is expected to be issued by the Ministry of Road Transport that would provide incentives to ensure increased use of ethanol for running vehicles. It is expected that in India, FFVs will present an advantage as they will allow vehicles to use different blends of ethanol mixed gasoline available in different parts of the country. Introduction of FFVs will require development of indigenous vehicle technologies for new vehicles and retrofitting solutions for older vehicles that will have to be approved by the Government. Introduction of FFVs require additional investment by OEMs for upgrading production lines and technology transfers to develop the flex fuel vehicles in India.
Ethanol has moved out of the research phase and may very well be the first bio-fuel to be implemented nationally. As ethanol is a fuel based on agriculture, its importance to a country like India, whose GDP is driven by agriculture based economy cannot be underestimated. The ethanol blending programme has taken centre stage and the sustained efforts of all stakeholders will usher in the era of flex fuel vehicles in India.
- National Biofuels Policy of India (2018) – Ministry of Petroleum, Govt of India
- Energy technology – Hisour https://www.hisour.com/common-ethanol-fuel-mixtures-40963/
- A Life-Cycle Analysis of the Greenhouse Gas Emissions from Corn-Based Ethanol – USDOE, ICF Report September, 2018
- Ben Mckay et. al. https://www.researchgate.net/publication/277353685_The_political_economy_of_sugarcane_flexing_initial_insights_from_Brazil_Southern_Africa_and_Cambodia
- SIAM White Paper on Alternative Fuels (2019)
- USDOE Fact Sheet https://afdc.energy.gov/fuels/ethanol_fuel_basics.html
- AIS 171 Safety Standard for Ethanol blended Motor Gasoline
- EIA Document https://www.eia.gov/energyexplained/biofuels/ethanol.php
- IS 17021 – BIS standard for E-20 ethanol fuel blends
Sr Deputy Director