With the rising hope of a greener future, the automobile industry is looking for substitute fuels that can lower the rate of greenhouse gases and make us less dependent on fossil fuels. Flex fuel has come up to be a very famous choice in providing an eco-friendly option for our vehicles. 

This fuel innovation fights the ever-increasing rise of fuel prices and, in due course, creates a pathway to a more sustainable future when a shift to full electrification is complete. 

Keep reading to stay informed about flex fuels, their significance, advantages, uses, and more.

The term flex fuel is short for ‘Flexible Fuel’. These vehicles run on petrol-ethanol blends of 0%-85% ethanol, E85. Essentially, such vehicles use different percentages of ethanol and petrol to make them more flexible, especially where ethanol can be easily accessed or subsidised. This fuel generates fewer emissions, hence cleaner air. 

At the same time, it gives an added advantage of more torque and horsepower than regular petrol.

Flex fuel, more precisely called E85, is primarily a mix of ethanol with petrol. The ratio can vary, but it generally contains about 85% ethanol and the rest petroleum. Ethanol itself is usually derived from renewable sources such as corn, sugarcane, or cellulosic materials. 

The renewable aspect makes flex fuel quite an attractive option for reducing greenhouse gas emissions compared with petrol derived from fossil fuels. Also, flex fuel may contain some additives to enhance performance and provide better stability in different weather.

According to reports, for making a full E100 ethanol compatible, the production cost of a petrol car will be escalated by about ₹17,000 to ₹25,000. For an E20 flex fuel or 20% ethanol blend compatible petrol car, additional expenditure of ₹3,000 to ₹5,000 has to be incurred at the production stage by car manufacturers. 

The approximate cost of components for making a petrol car E20 or E100 flex fuel compatible is shown in the figures. The research and development expense will add at least ₹1,000 to ₹2,000 to this estimate per vehicle. 

For that reason, the flex fuel vehicle E20 could carry a premium of ₹4,000 to ₹6,000 over a comparable petrol car; an E100 version will cost perhaps ₹19,000 to ₹27,000 more than a petrol variant.

The following are the notable benefits of flex-fuel:

• Lower Dependence on Fossil Fuels: Ethanol is a renewable source of energy and has reduced dependence on non-renewable fossil fuels like petrol.

• Environmental Benefits: Ethanol burns cleaner than petrol and reduces emissions of carbon footprints, greenhouse gases, and other harmful pollutants.

• Economic Benefits: Ethanol production can further boost local economies, especially for the places where jobs can be generated and locally cultivated crops used.

• Energy Security: Using ethanol produced domestically can provide energy security by avoiding dependence upon foreign oil.

• Tax Benefits: Consumers driving flex fuel automobiles can enjoy tax credits that can significantly curb or even eliminate their tax obligation.

Unlike the plus points, there are certain drawbacks of flex fuel that you need to be aware of:

• Lower Fuel Efficiency: Ethanol has less energy content per volume compared to petrol, so it offers lower fuel efficiency and might prove costlier to travel the same distance.
• Availability: One might not find E85 fuelling stations around them as easily as they would find regular petrol pumps, hence reducing the feasibility of using flex fuel vehicles in those regions.
• Vehicle Performance: It has been found in some flex fuel vehicles that are fuelled with E85 instead of petroleum, and the acceleration and power are reduced.
• Infrastructure Costs: Construction and maintenance of ethanol production facilities and building up of distribution infrastructure are expensive.
• Mileage: One of the main problems of driving a flex fuel vehicle is its petrol mileage. While some experts claim that the mileage for flex-fuel cars is identical to that of normally powered fuel, others say that they have lower mileage.

Ethanol flex fuel, better known as E85, is a fuel blend mainly comprised of ethanol and petrol. More specifically, it contains approximately 85% ethanol and 15% gas. It is a fuel specifically made for Flex Fuel vehicles capable of running on anything from pure petroleum to E85 or any mix in between. 

Generally, ethanol is produced from renewable biomass like corn, sugarcane, or cellulosic materials, making E85 a more environmentally sustainable fuel than conventional petrol. Ethanol Flex Fuel offers fuel choice flexibility, potentially reduced emissions, and renewable sourcing while boosting farm economies.

A Flexible Fuel Vehicle (FFV) is an automobile designed to run on a blend of different fuels, such as ethanol and petrol blends like E85. FFVs have specially developed engines and fuel systems that allow them to run on unleaded petrol, any mix of petroleum and ethanol up to 85%, or 100% ethanol by volume. 

They are designed to give consumers flexibility at the gas pump, allowing the use of conventional petrol or a combination of renewable ethanol. FFVs are identified by flex-fuel badging or labelling, which makes them easily detectable to consumers at dealerships or when filling up.

Basically, the flex fuel engine is any type of internal combustion engine that can operate on both ethanol and petrol individually or in any combination. This includes pure petroleum through high-concentration ethanol mixes, typically E85. 

Flex fuel engines are specially designed using specific materials and components that could easily work with the differences in ethanol's makeup from that of petrol, such as the higher octane ratings and different combustion characteristics. 

Such engines incorporate sensors and electronic fuel management systems, enabling them to detect a combination of fuel while in operation and adjust accordingly to parameters such as fuel injection timing and air-fuel ratio.

Take a look at some flex car vehicle models that are getting launched in India soon:

1. Maruti Suzuki WagonR Flex Fuel

During the 2023 Bharat Mobility Expo, Maruti Suzuki displayed the prototype of the WagonR flex fuel, giving an idea about the company's plans to have its entire model line-up flex-fuel ready by 2025. According to reports, the flex fuel WagonR emits almost 80% carbon and can run from E20 to E85.

2. Mahindra XUV300 Flex Fuel Prototype

Mahindra also showcased the XUV300 flex-fuel prototype at the Bharat Mobility Expo. It runs on a blend ratio of 20% to 85% ethanol. According to the company, the flex-fuel engine in the XUV300 produces 109 BHP and 200 Nm of max torque. As estimated, the company will introduce its new flex-fuel engines in the market by 2025.

3. Toyota Innova Hycross Flex Fuel

Not too long ago, Toyota showcased the Toyota Innova Hycross as the lead candidate of its flex-fuel engine program, where the vehicle run on E85 blends easily. This was to display the potential of running ethanol-rich blends for low carbon emissions with the same 2.0-litre petrol engine of the Innova Hycros hybrid.

4. E20 Flex Fuel Cars

Although many car manufacturers have announced that their vehicles are compatible with E20 blends, consumer complaints about reduced performance after using E20 petrol have started coming up on social media. In response, car manufacturers have asked owners to continue using unblended petrol or E10 blends.

Flex fuel cars are not very prevalent in the Indian market at present. There are some flex fuel cars that will be launched soon in the upcoming years. 

Moreover, the Indian government has ensured a market for flex-fuel vehicles by stipulating that every new vehicle sold in the country by 2025 must be flex-fuel compatible.

Flex fuel brings several benefits if put into perspective. Among them, it provides better fuel choice flexibility, fewer GHG emissions than traditional petrol, and brings income to the agricultural economy through ethanol production. 

On the negative side, there are issues with access to E85 refuelling stations, the potential fuel efficiency of a vehicle running on the higher ethanol blend, and controversy around the lifecycle environment impacts of ethanol production. 

Flex fuel is a potential step towards sustainable transportation, offering a cleaner set of emissions with higher energy security. As much as it faces challenges with reduced fuel efficiency and limited infrastructure, its flexibility and environmental advantages still underline its role in transitioning to cleaner, renewable energy sources.