EV Cost per km Calculator
Calculate the running cost per km of your electric vehicle.
Compare home vs public charging costs and see annual fuel savings vs petrol.
The running cost of an EV is primarily the electricity cost for charging. This is dramatically lower than petrol — typically 3–6x cheaper per km depending on energy prices.
Cost per km formula: Cost per km = electricity price (per kWh) × energy consumption (kWh/100km) / 100
Worked example (home charging):
- Consumption: 16 kWh/100km
- Home electricity: £0.25/kWh
- Cost = 0.25 × 16 / 100 = £0.04 per km = 4p/km
Public rapid charging example:
- Same consumption: 16 kWh/100km
- Public rapid charger: £0.65/kWh
- Cost = 0.65 × 16 / 100 = £0.104 per km = 10.4p/km
Comparison with petrol:
- Petrol car: 7L/100km at £1.50/L = £0.105 per km = 10.5p/km
- EV at home: 4p/km — 2.6x cheaper
- EV at public rapid: 10.4p/km — comparable to petrol
Annual savings estimate: At 15,000 km/year, switching from petrol to home-charged EV saves: (10.5p − 4p) × 15,000 = £975/year in fuel alone.
Note: EV servicing costs are also lower (no oil changes, fewer brake replacements due to regenerative braking, no timing belt). Total annual running cost savings are typically £1,200–£2,000 for a typical driver.