EV vs Petrol Cost Comparison
How to Use
Introduction
The usual answer to whether an EV saves money quotes a per-kilometre figure and quietly omits the extra paid at purchase. This page puts annual distance, fuel consumption, tariff, electricity consumption, the price gap and the number of years into one table, then reports both cumulative savings and payback.
The example uses 15000 km a year, petrol at CNY 7.8 per litre and 7.5 L per 100 km, giving 8775 a year for the petrol car; electricity at CNY 1.1 per kWh and 15 kWh per 100 km gives 2475 a year for the EV. That is 6300 saved per year, 31500 over five years, 1500 net after a 30000 price gap, and roughly 4.76 years to pay back.
Switch the tariff to a public fast charger, or drop the annual distance to 8000 km, and the net figure turns negative immediately. That says more than a per-kilometre saving ever does.
Key features
- Side by side: Annual energy cost for petrol and electric sit on one row, with the gap beside them.
- Same mileage: Both cars use the annual mileage you enter. Different mileages need separate runs.
- Payback years: The price gap divided by annual saving gives how many years it takes to recover.
- Net after gap: Cumulative saving minus the purchase price gap is what actually stays in your pocket.
- Negative saving: If saving turns negative, no payback year is returned. The tool does not invent one.
- Editable constants: Fuel price, electricity price and consumption are built-in references you can replace.
How to use it
- Annual distance: Estimate the yearly mileage first. Both cars must be compared over the same distance.
- Petrol price, Petrol consumption: Enter the price per litre and litres per 100 km; together they give the petrol car yearly energy cost.
- Electricity price, EV consumption: Enter the price per kWh and kWh per 100 km; the EV cost is worked out over the same distance.
- Purchase price gap: Enter what the EV costs extra on the road. It is subtracted from the accumulated saving.
- Years compared: Enter how long you plan to keep the car, then see whether the payback period fits. No payback is shown when yearly saving is negative.
Things to keep in mind
- Reference rates: Fuel price, electricity price and consumption are built-in references.
- On-the-road gap: Enter the on-the-road price gap, not the list price gap.
- Same mileage: Both cars must use the same annual mileage to be comparable.
- Payback: Payback years need positive annual saving; a negative one returns no figure.
- Energy only: Energy only: insurance, maintenance and resale are excluded.
The comparison covers energy only. It does not attempt to price insurance, servicing, battery degradation or resale, so a short payback period is not a full ownership verdict. If the two cars will not cover the same distance, run the calculation twice with each mileage and compare the yearly savings rather than trusting a single shared figure.
The purchase price gap belongs in the calculation as an on-the-road figure, since taxes, subsidies and dealer discounts are exactly what make two otherwise similar cars hard to compare. Negative annual saving returns no payback figure at all rather than a negative year count, which would be meaningless.