4th Mar 2026

Home EV Charging vs Petrol Costs — How Much You Could Save Per Year

Charge at Home. Save Every Mile.

Thinking about switching to electric?

If you drive 12,000 miles per year, here’s what the numbers look like when charging overnight on an off-peak tariff with Octopus Energy.

Assumptions:

• Overnight tariff: ~7.5p per kWh (Intelligent Go style rate)?• Typical EV efficiency: 3.5 miles per kWh?• Petrol car average: 45 mpg?• Petrol price: £1.45 per litre

? Electric Car (Home Charging Overnight)

12,000 miles ÷ 3.5 miles per kWh = 3,430 kWh per year

3,430 kWh × £0.075 = ~£257 per year

That’s around 2.1p per mile

? Petrol Car (45 mpg)

12,000 miles ÷ 45 mpg = 267 gallons?267 gallons = 1,214 litres

1,214 litres × £1.45 = ~£1,760 per year

That’s around 14.6p per mile

???? Estimated Annual Saving:

Around £1,500 per year

And that’s before factoring in:?• Lower servicing costs?• No oil changes?• No exhaust system?• Potential tax savings

Home charging at off-peak rates completely changes the ownership equation.

If you're covering average UK mileage, the maths is becoming difficult to ignore.