A fifth of your petrol is now alcohol. Here's what that actually does to the price, the mileage, and the country.
Crude, the rupee, ethanol, and what petrol costs both before tax and at the pump — five numbers you can check, and your own arithmetic on top. No press release. By the end you'll have built both sides of the ledger yourself, and you decide.
The numbers here are pinned to 2026's expensive stretch — a barrel up near its year's highs, the rupee near its weakest — on purpose: that's the hardest case for ethanol to win, so if it holds up here it holds up anywhere. (Crude has since eased off that peak; the Delhi pump stayed frozen at ₹102.12 the whole way.) Nothing below is a benefit claim — it's just how that pump price is assembled, piece by piece.
Before anything else, the thing people get wrong. "E20" is not five litres of petrol plus one of ethanol. It's one litre, in which a fifth is ethanol. Pick a blend and see the split in a litre you actually buy.
Petrol's price is set by a world market in dollars. Ethanol's is fixed in rupees, once a year, by the government. Here is every price it's been set at — and the two numbers we'll never let it out of for the rest of this page.
Fix the two things that set petrol's price — the barrel and the rupee — and watch the pump. Then add ethanol into the litre and watch the same shock land softer. This is the whole mechanism, in your hands.
Five years of the Delhi pump, built honestly. Each coloured band is a slice of what a litre would cost if the price simply tracked crude — the barrel, a steady refiner's margin, the frozen duties, the dealer and VAT. Watch the crude band swell through 2022 and again in 2026, while the teal line — what you actually paid — barely lifts. The space above it, up to the top of the wave, is your shield.
The next few years are the question: a rupee drifting weaker, a crude market that lurches on every headline. Push both and watch the pump price of each blend. The faint bars are where they sit today; the solid ones are your scenario. Watch the gap between E0 and E20 open up.
Section 06 showed ₹90 is five years behind us. So here is the whole landscape at once. Ethanol is held at ₹73 throughout; drag the barrel and the rupee — or pick a scenario — and find the narrow green band where E20 lands back between ₹80 and ₹90. The white ring marks crude near its 2026 high.
Here is the honest cost. We assume a 10% mileage drop at E20 — worse than the 6–7% most engines actually lose, to give the doubters the benefit. Set your real mileage and see the extra you'd pay, per kilometre and per month. Mileage is the cost we can price; there's one we can't, and we name it below.
Now the other side, from the very same driving. The ethanol in your tank is petrol India didn't import — not litre-for-litre, since ethanol carries less energy, but real rupees that stayed in the country instead of leaving it, and went to an Indian field instead of a foreign one.
No verdict from us. Here is what you assembled — the cost to you on the left, the money that stayed in the country on the right — from your own numbers, with every assumption tilted against the case for ethanol.