• Source:JND

Ethanol Blending Mileage Drop India:  The Indian government has recently launched the E85 petrol in India, and it costs Rs 20 less than the regular E20 petrol. While the country is looking at E85 as an alternative to strengthen its energy security and save foreign exchange worth billions, the anxiety around ethanol-blended fuel or E20 is still there. Does E20 fuel damage engines? Does E20 petrol reduce mileage? These are still some of the most searched questions regarding the ethanol-blended petrol. So, does E20 petrol really harm the engine and reduce mileage, or is it just a myth?

What Is E20 Petrol?

E20 is a rating given to a certain type of flex fuel. A flex fuel is a blend of two types of fuel, and it acts as an alternative to traditional fuel types, such as petrol and diesel. Flex fuel can be obtained by blending petrol with an oxygenate, such as Ethanol or Methanol. Damage to the engine metal and plastics, along with phase separation, are some of the most common risks associated with Methanol blend fuel, and thus, most of the major global automotive manufacturers prefer ethanol blend petrol.

E20 simply means a fuel type which contains 20 per cent of Ethanol blended with 80 per cent of petrol. Similarly, E25, E30, or E85 are fuel blend ratings. In these ratings, E is used here for Ethanol, while the number stands for the percentage of Ethanol in the fuel type.

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Does E20 Fuel Damage Engines?

Pre-BS-6 phase 2 vehicles, or simply vehicles manufactured before April 2023, are more prone to issues from E20 fuel. Similarly, vehicles with carbureted engines or older rubber and plastic fuel lines might be at a higher risk. This is further proved by a survey done by Local Circles. As per the survey, 28 per cent of old vehicle owners have confirmed experiencing unusual wear and tear and a need for repair.

The survey received 37,000 responses from petrol vehicle owners from 331 districts of the country. Ethanol is more of a solvent, and it can damage metal tanks, fuel lines, and carburettors in the older vehicles. Additionally, as per several reports, older fuel hoses, seals, and gaskets are not ethanol-resistant, and they might get damaged from E20 petrol.

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Does E20 Petrol Reduce Mileage?

Several vehicle users have reported reduced mileage after the rollout of E20 petrol. While E20 petrol might not damage vehicles compatible with ethanol-blended fuel, the fuel efficiency is certainly an area which will be affected. Why? Well, while ethanol certainly has a higher Research Octane Number (RON), it has a lower energy density when compared to regular gasoline. Due to lower energy density, the ECU will be required to inject an increased amount of fuel to achieve the same amount of power. As per experts and several reports, a flex fuel with 20 per cent of ethanol is expected to result in a 7 to 8 per cent reduction in fuel efficiency.

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E20 Petrol: What Should Vehicle Owners Do?

As mentioned earlier, the higher ethanol blend in flex fuel affects older vehicles, especially vehicles from the pre-BS-6 phase 2 stage. Vehicles manufactured after April 2023 are compatible with ethanol-blended fuel, and thus, they don’t require any additional care.

However, older vehicle owners need to take some precautionary measures. To begin with, they can add special ethanol-compatible fuel additives. Vehicle owners are also advised to keep their tanks filled to the top, so that the moisture absorption can be reduced. Lastly, to mitigate the effects of E20 petrol on older vehicles, owners can upgrade the rubber and plastic parts of their vehicles.


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