E20 Fuel: All You Need To Know

E20 Fuel: All You Need To Know

BS6-II norms were introduced in April 2023 in India and to be compliant, auto manufacturers had to modify their engines to make them compatible with E20 fuel. With E20 fuel, the automotive industry can look forward to a cleaner and more sustainable future in the ever-changing world of alternative fuels. India has a goal to cover the entire country with E20 fuel by 2025. In this article, we will discuss the E20 fuel in great depth, including its composition, manufacturing methods of ethanol, its uses, efficiency as an automotive fuel, compatibility with various engines, and environmental impact.

What is E20 fuel?

Automotive fuel blends comprising 20% ethanol and 80% gasoline are referred to as E20 fuel. A biofuel that is sustainable and biobased, ethanol is usually made from plant resources like corn, sugarcane, or other biomass. Reducing the dependency on fossil fuels, cutting greenhouse gas emissions, and encouraging the use of renewable energy sources are some of the primary goals of ethanol use in gasoline blends.

Since ethanol contains more oxygen than gasoline, an E20 fuel blend offers significant advantages like increase compression ratio due to inherent higher-octane number, resulting  in more efficient combustion and thus accounts for lesser tailpipe emissions.  Ethanol comes from renewable resources, and it burns cleaner than other fuels. Here are some key things to know about ethanol as a compound, before delving deeper into its use as an automotive fuel.

What is ethanol?

Ethanol, also known as ethyl alcohol, is a type of alcohol that is commonly used in various applications. It is a clear, colourless liquid with a characteristic odour and taste. Ethanol has the chemical formula C2H5OH and is composed of carbon, hydrogen, and oxygen atoms. Pure ethanol is nontoxic and biodegradable, and if spilled, they break down into harmless substances. However, fuel ethanol contains denaturants to make fuel ethanol undrinkable.

How is ethanol sourced?

Ethanol can be produced from various sources, but it is often derived from renewable resources such as crops like corn, sugarcane, barley, and wheat. It can also be produced from cellulosic materials like agricultural residues and wood.

What are ethanol’s uses?

Fuel: Ethanol is commonly used as a biofuel. It can be blended with gasoline (as in E10, E15, E20 blends etc) or used as a standalone fuel for engines designed to run on ethanol. It is flammable and can be used as a fuel for combustion engines. Ethanol burns more cleanly than some other hydrocarbon-based fuels.

Industrial solvent: It is widely used as a solvent in the production of various compounds, including pharmaceuticals, perfumes, and personal care items.

Beverage: Ethanol is the type of alcohol found in alcoholic beverages. In this context, it is produced through the fermentation of sugars in fruits, grains, or other plant materials.

Antiseptic: Ethanol has antiseptic properties and is commonly used as a disinfectant for medical and household purposes.

Ethanol is a versatile compound with a range of applications, and its use has environmental benefits, especially when produced from renewable sources. It is a key component in the development of renewable and sustainable energy sources.

How is ethanol produced?

Ethanol is produced through fermentation. Plant-based sugars and starches are the primary ingredients used to produce ethanol.

Ethanol can be produced from various crops rich in sugars or starches. Common feedstocks include corn, sugarcane, barley, wheat, and sorghum. To produce ethanol from these crops, the plants are harvested and processed to extract the sugar or starch content. However, ethanol can be produced from other cellulosic materials as well.

The extracted sugars or starches from the above processes are then converted into ethanol through fermentation. Microorganisms such as yeast or bacteria are introduced to the feedstock to metabolise the sugars and produce ethanol and carbon dioxide. The fermentation process takes place in fermentation tanks under controlled conditions.

Once the process of fermentation is finished, a mixture containing a combination of ethanol, water, and other by-products is obtained. The next step, which is meant to separate ethanol from water and other impurities is known as distillation. As a part of the distillation process, the mixture is heated. Since ethanol has a lower boiling point than water, it evaporates and is then condensed back into liquid form. If any residues of water are remaining in this liquid, an additional step namely dehydration is employed to remove the remaining water and increase the ethanol concentration. Dehydration can be carried out through various methods, including molecular sieves or azeotropic distillation.

Depending on the required ethanol concentration, the resultant ethanol can be mixed with gasoline to create ethanol-blended fuels like E10, E20, or E85.

How are engines running ethanol blend fuels different from pure gasoline engines?

The qualities of pure gasoline and ethanol differ, so adapting engines to run on, say, E20 fuel (20% ethanol and 80% gasoline combination) usually involves multiple changes and considerations. The following are some significant adjustments that auto manufacturers may need to make:

1. Compatibility of materials:

Since ethanol and gasoline have differing characteristics, several materials that are frequently used in petrol fuel systems do not work well with greater ethanol blends. Manufacturers must make sure that parts of engines, including gasoline tanks, seals, gaskets, and fuel lines, are constructed of materials suitable for use with ethanol.

2. Fuel System modifications:

It is also necessary to modify the fuel delivery system, which includes the pumps and injectors, to accommodate the unique characteristics of E20. Because it contains more oxygen than gasoline, ethanol burns a little differently as compared to gasoline. Engine control systems require calibration to maximise E20 performance.

3. Engine modifications:

To achieve the best possible air-fuel mixture and ignition timing for E20, the engine control unit (ECU) needs to be recalibrated. This minimises emissions while ensuring effective combustion and performance.

4. Sensor modifications:

It might be necessary for some sensors, including oxygen and fuel composition sensors, to work with ethanol mixtures. These sensors are essential for giving the ECU feedback so that the engine can be controlled precisely.

5. Testing for durability:

To guarantee that every part of an engine built for use with E20 can endure the long-term corrosive effects of ethanol, the engines must go through extensive durability testing.

Advantages of E20 fuel

1. Renewable:

One of the key ingredients of E20 is ethanol, which is made from renewable resources like corn, sugarcane, or biomass. Hence, E20 is a greener and more sustainable fuel than regular gasoline.

2. Energy security and domestic production:

Many countries generate their own ethanol, which lessens their reliance on oil imports. By generating employment in the agriculture and biofuel industries, this improves energy security and boosts regional economies.

3. Assistance for agricultural sectors:

Ethanol manufacturing frequently depends on crops like corn and sugarcane. The development of biofuel from these crops gives farmers new sources of income, enhancing the long-term financial viability of farming communities.

4. Lower emission of greenhouse gases:

The carbon footprint of ethanol is smaller than that of gasoline. Reducing greenhouse gas emissions during the manufacture and combustion of ethanol aids in the fight against climate change.

5. Greater octane rating:

The octane rating of ethanol is higher than that of gasoline. Better engine efficiency, performance, and combustion characteristics may result from this. Compression ratios and thermal efficiency can be increased in engines tuned for greater ethanol blends.

6. Resistance to engine knock:

Since ethanol has a higher-octane rating than gasoline, it lowers the possibility of engine knock, enabling more aggressive engine tuning and leading to a potential increase in power output in engines meant to run on E20.

7. Possible financial savings:

Producing ethanol in large volumes is less expensive than producing gasoline. Considering regional market dynamics and governmental regulations, E20 may result in lower costs for customers.

It's crucial to remember that while E20 has numerous benefits, there are drawbacks as well.

Disadvantages of E20 Fuel

1. Compatibility with existing engines:

Not every engine on a vehicle on the road today is made to run on E20. To guarantee compatibility, manufacturers must alter engines and fuel systems. Upgrades or retrofits may be necessary for older vehicles.

2. Infrastructure cost:

Significant expenditures in additional infrastructure, such as storage tanks, pumps, and pipes, are necessary for the widespread implementation of E20.

3. More corrosive:

Compared to gasoline, ethanol has different chemical characteristics, and it is corrosive to several materials that are frequently used in fuel systems. Component deterioration or damage could result from compatibility problems.

4. Absorption of water:

Because of its hygroscopic qualities, ethanol can draw moisture from the surrounding air. Phase separation brought on by this water absorption may result in corrosion if the manufacturer doesn’t account for it.

5. Agricultural effects on the environment:

Intensive farming methods used to produce ethanol may be a factor in environmental problems such as soil erosion, pesticide use, and deforestation. Utilising sustainable farming methods is essential to reducing these effects.

To sum up, E20 is at the forefront of renewable and sustainable fuels. The push from the government too has made it necessary for manufacturers to develop vehicles which are compatible with ethanol blends.