Union minister for road transport and highways Nitin Gadkari, defending the government’s ethanol-blending programme, said in an interview that motorists who dislike the blended fuel had another route open to them. “People who do not want ethanol-blended fuel can go for 100% petrol, but they will have to pay more,” he said.
Key Features
The remark lands in the middle of concerns about the nationwide rollout of E20 petrol — a blend of 20% ethanol with petrol — with some motorists complaining of lower mileage and accelerated wear on older engines. Here’s what is actually on offer: The closest option to pure petrol at Indian fuel stations is the small family of 100-octane fuels. Indian Oil Corporation’s XP100, launched in December 2020, is one such example. Hindustan Petroleum Corporation Ltd (HPCL) sells the other 100-octane brand, Power100. In a response on X to a customer query in August last year, HPCL said ethanol content in its variants was up to 4.5% in Power100. Refiners say octane-100 petrol, although developed for high-performance engines that need a more knock-resistant fuel, can be used for standard cars. Put plainly, the fuel will run in a regular sedan or hatchback, and may deliver a smoother drive, but a mass-market engine may not fully draw the full advantage of 100-octane. The instrumental catch that stands in the way of widespread adoption of 100-octane petrol is their price. At the moment, these fuels cost ₹167- ₹170 per litre in Delhi, about 60% more than regular petrol. For consumers outside the metros, 100-octane — or ethanol-free — petrol remains largely inaccessible.
Because they need to maximise energy output and offer stability that old or high-compression engines require, the basis for low ethanol content in Octane-100 fuels is the target customer: typically high-performance vehicles such as luxury, sports cars or classics rely on full-petrol fuels. The government has maintained that some vehicles may see mileage drop up to few percentage points on E20 but assert that the blend is a cleaner fuel, offers India some energy security by minimising the amount of crude oil import, and there is no proof of engine damage. For consumers hunting for near-pure petrol, though, the choice is not straightforward. XP100 has trace amounts or effectively no ethanol content, estimates suggest. Separately, Bharat Petroleum sells Speed100. Ethanol, per unit of volume, packs lower energy than pure petrol. Availability is the second barrier. These are mostly available in cities, and that too at select pumps. Some premium petrol on the market — HPCL’s Power99, Bharat Petroleum’s Speed97, Shell’s V-Power — are sometimes assumed to carry less ethanol than regular E20. That assumption conflates two separate characteristics.
XP100 is manufactured at the company’s Mathura refinery using an indigenous refining process it calls OCTAMAX, according to Indian Oil. At the time of the launch, the government noted how 100-octane fuel was part of “a niche market for luxury vehicles that demand high performance”. Indian Oil said on its website that the use of XP100 for standard cars “will offer smooth engine operation with improved performance in terms of fuel economy, emissions and acceleration” though “the complete benefits” are “enhanced when used in matching engine configuration”.
What Could Be Better
Because it is a niche product, another aspect, car enthusiasts have said, is that 100-octane petrol moves slowly through the retail chain. Because ethanol is hygroscopic and can absorb moisture from the air, if blended with ethanol, the risk of water contamination and fuel degradation may increase. That means the fuel often sits for extended periods in underground storage tanks at petrol stations. Refiners sidestep that potential problem by keeping the blends at low levels or by opting for near-pure petrol.
Verdict
The octane rating measures a fuel’s stability under compression. That secondary, uncontrolled burn is what drivers hear as engine knock, which can over time damage pistons. Ethanol content, on the other hand, refers only to how much bio-derived alcohol has been blended into the petrol. HPCL’s tweet laid that out: “Ethanol content is approx. These blends help reduce emissions and enhance fuel efficiency. So what explains the anecdotes of better acceleration and fuel efficiency that many are experiencing? It is simply that petrol, per unit, packs more energy than ethanol. But the debate is not only about acceleration or mileage. Higher ethanol also requires some component changes since this fuel could corrode some rubber components more readily.
The two can move together — ethanol itself has an octane rating of around 108 RON (research octane number), so blending it up to 20% lifts a regular fuel’s overall octane by about six RON. Conversely, premium petrol can have a higher octane rating while still containing 20% or lower ethanol. 20% in regular petrol, 15% in Power95, 11% in Power99, and up to 4.5% in Power100. Many are also concerned that their cars, usually those sold before 2023, are not equipped to deal with E20.
Since this April, all petrol available in India is at least 95RON – a mandate that is largely seen as having been possible due to the mandatory 20% ethanol blending.
The higher the number, the more the fuel resists auto-ignition, which the US Energy Information Administration (EIA) defines as the situation “when rising temperature and pressure from the primary combustion causes unburned fuel to ignite”. In August 2025, Indian Oil also said on X that XP95 was blended with “either 10% or 12%” ethanol depending on supply location, but it is not clear if the product retains the same ethanol blending proportion today.
