I have been logging every fuel fill of my car since December 2017. Eight years, 180 fills, ₹7.28 lakh, and 18 tonnes of CO₂. Twenty months ago, I bought an electric bike and started logging that too.

This is not a coincidence or a conversion story. The Hyundai Creta is still running. The Ultraviolette F77 Mach 2 does the city runs. And because I log everything, the comparison became inevitable.

I wrote about this habit in an earlier post, The Lost Art of Documentation. The argument is simple: you cannot study what you did not record. Eight years of fuel logs have told me things I never consciously tracked. That I paid ₹1.36 lakh extra purely because petrol prices rose 37% since 2017. That December is consistently my heaviest travel month across all eight years. That my car has emitted 18.2 tonnes of CO₂ into Bangalore’s air. None of that came from memory. Memory would have given me “it costs a lot to run a car.” The log gives me the exact shape of that cost.

The bike, twenty months in, costs ₹0.39 per km to run on electricity. The Creta costs ₹8.68 on petrol. That is a 22x gap, not a marginal difference. The bike has saved an estimated 196 kg of CO₂ over 3,000 km. The car has produced 18.2 tonnes over 83,846 km. One number is a promising start. The other is the context that keeps it honest.

This is not a pro-EV piece. The manufacturing footprint, the battery lifecycle, the grid’s coal dependency, none of that disappears because the tailpipe does. But the running cost argument is settled, and eight years of logged petrol data make that clearer than any manufacturer claim could.

The full article, with charts, a side-by-side comparison table, and the complete 8-year car data log, every fill and every service, is here: 90,000 km of Petrol vs 3,000 km of Electrons.