EV vs petrol: compare energy cost without ignoring the rest

How to compare EV electricity and petrol fuel fairly, including real-world efficiency and charging losses.

Editorial review: Oct 15, 2026 · Educational content · No sponsored recommendations

Put both vehicles on the same distance

Energy comparisons should start with identical monthly or annual distance. Petrol consumption is commonly expressed as liters per 100 km, while EV consumption is kWh per 100 km.

Home and public charging can have very different prices

An EV charged mostly at home can have a different energy cost from one relying on fast public chargers. Use a blended electricity rate if your charging is mixed.

Real-world efficiency matters

Temperature, speed, traffic, tires and driving style change both fuel and electricity consumption. Use observed efficiency rather than brochure values whenever you have it.

Energy savings are not total ownership savings

Purchase price, battery warranty, depreciation, insurance, maintenance, tax treatment and charging hardware can outweigh the energy difference. Keep the energy calculation as one layer of a larger ownership model.

Sensitivity is more useful than certainty

Change fuel price, electricity price and distance independently. If the conclusion survives large changes, it is more robust than a result that flips with a small assumption adjustment.

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