E20 petrol: Good, bad and better. Here are findings from a real study, not influencers' gyan

As we have already reported that automobile engineers working with various major automakers have already admitted that there will be a fuel efficiency drop between two to five per cent, depending on the vehicles, due to E20 fuel. They have also admitted that there are risks of damage to various components of vehicles, but that will occur in the long term, not immediately. In the meantime, no automaker has come up with facts or realistic findings of E20’s impact. This has further raised the anxiety of the vehicle owners. Meanwhile, a Bengaluru-based vehicle tuning company Harmonixx Tuning has come up with its findings, which explains the impact of E20 in a detailed manner. The firm claims to have extensively tested ethanol blended fuels since October 2020. According to them, if you own a car produced after 2015 and it is fuel-injected, there is nothing to worry about. This comes in contradiction with the perception widely spread that vehicles built after 2023 are vulnerable to see damage in their critical powertrain components. Also, what no one is paying attention at is that E20 is not being sold at the fuel stations around us abruptly. The only ruckus is because the government has announced that India has achieved the target of E20 five years before the original deadline of 2030. The reality is that ethanol blended petrol is being sold across the country for quite some time. The ethanol content in the motor fuel has increased gradually. Petrol sold in India prior to 2021 was just petrol combined with other additives like injector cleaners, octane boosters, dye to help identify the fuel, detergents, etc. While the central government’s proposal to blend ethanol in petrol had begun back in September 2002, serious blending started only after the Covid-19 pandemic, once the restrictions on ethyl alcohol was over. The earliest ethanol blend recorded in India was with Power 99, which had E07-E08 (seven to eight per cent ethanol blend) in late 2022, and XP95, which had E05 in April 2023. Now, leaving the history and timeline, let’s come to the advantages and disadvantages of the ethanol blended petrol. Ethanol blended petrol: What’s good about it?While the government has been lobbying for ethanol blending and citing many reasons including the reduced import bill, lesser dependency on crude oil and reduced cost of fuel, let’s just focus on the technical aspects, not economic ones. Ethanol may not be the regular fuel for vehicles, as we have known so far in India, but there are some advantages of this being blended into petrol. Ethanol has a much higher Research Octane Number (RON) rating compared to petrol. Because of the aditional RON, ethanol has a higher knock resistance than regular petrol. It also helps reduce charge temperature, emission of Carbon Monoxide (CO) and Hydrocarbon (HC). It helps reduce soot formation, which is a deep black powdery or flaky substance consisting largely of amorphous carbon, produced by the incomplete burning of organic matter. Ethanol blended petrol: What’sbad about it?It’s not that ethanol has only advantages, but using petrol blended with this comes with a lot of disadvantages as well. Ethanol has a much lower energy density compared to regular petrol. This means, you need to burn nearly 33 per cent more fuel to achieve the same power, which is why you are seeing a drop in your vehicle’s fuel efficiency. This fuel economy drop could range between three to four per cent while using E10 fuel and in case of E20, it could be between six to eight per cent, depending on multiple factors. In older vehicles, mostly the non-fuel-injected ones, the materials used for rubber hoses, gaskets, seals, etc., might not be as durable as those manufactured later due to the use of E20. In such cases, the vehicle owners will have to opt for replacement of those parts. However, with the vehicle aging, replacement of various parts is common anyway, as they become brittle over time. This happens regardless or whether pure petrol is used or blended fuel. Another key disadvantage of ethanol is its hygroscopic nature, which mean it can absorb moisture or water. If ethanol-blended fuel comes in contact with water, ethanol mixes with water completely. If water enters the engine, the pistons can compress ethanol but cannot compress water. This is how a hydrolock can occur. However, hydrolocking is extremely rare. Ethanol could create trouble while starting an engine in very cold climate. However, that could happen if the engine is being run on high ethanol blends, like in excess of E50. In most parts of India, such temperature is not common. Also, India has just reached 20 per cent fuel blending threshhold. E20 petrol: Which engines can run safely on it?Almost all naturally aspirated petrol engines (post-2018). If you own a car that is older than 2015, it is already a decade old, which means you should be doing preventive maintenance anyway. These include injector replacement, fuel filter and fuel pump changes, along with replacing hoses, gaskets, and seals, which will naturally wear out over time. Almost all the naturally aspirated petrol engines, built after 2015 can run safely on E20 fuel, claims the tuning firm. Just make sure you perform the periodic maintenance as prescribed by the vehicle manufacturer. Also, practice preventive maintenance as and when necessary. Some of the preventive maintenance include changing engine oil every 4,000 km if using mineral oil. In case of synthetic oil, change oil every 7,500-8,000 km. Also, change spark plugs after every 15,000-20,000 km. E20 petrol: Should you be worried?The tuning firm claims that if the car is manufactured after 2015 and it is fuel-injected, there is nothing to worry about. The vehicle’s ECU is smart enough to adjust the fuel trims accordingly, and will maintain the air–fuel ratio (AFR) it is programmed to target. Social media hype is just that – hype. The influencers telling you the downside of the E20 and ethanol possibly has no technical knowledge about the internal combustion engine (ICE). Using E20, your engine cannot die. The only real downside is a drop in fuel efficiency. Get insights into Upcoming Cars In India, Electric Vehicles, Upcoming Bikes in India and cutting-edge technology transforming the automotive landscape. First Published Date: 25 Aug 2025, 13:55 pm IST
Source: hindustantimes.com