Electric or combustion: what a kilometre costs
An honest comparison between filling up and charging. An electric kilometre has no single price: it depends on where the kWh come from — home, your own system, or public chargers. Change the mix and watch the verdict change.
The car you have today
The electric car
Km per kWh are what you get from the energy in the battery. About 12% is lost between the socket and the battery: we add it for you, you don't have to.
How you charge
This is the parameter that decides the answer. Charging at home costs a quarter of a rapid charger, and from your own system it costs less still. Enter how much each one weighs: the shares normalise themselves.
At home, from the grid
The tariff on your bill.
From your own system
Not free: it is a kWh you don't sell to the grid. Its cost is the revenue you give up.
Public charger
AC is around €0.45/kWh, rapid DC around €0.79.
How much you drive
Where you live
The comparison
Combustion
0,121 €/km
Electric
0,090 €/km
26%
That is what you save on every kilometre, with the charging mix you entered.
An indicative estimate, not a quote. Fuel and energy prices change constantly: replace them with what you actually pay.
On the same tankful
The question you start from: for what you spend on one fill-up, how far do you get each way?
With combustion
577
kilometres
With electric
781
kilometres
For the same money, electric takes you 204 km further.
How we get to these numbers
Cost per kilometre
Fuel price divided by the km you get from a litre, against the average price of your kWh divided by the km you get from a kWh. It is the only figure that lets you compare two things sold in different units.
Charging losses
Rated km per kWh are measured on the energy in the battery, but your bill counts the energy at the meter. About 12% is lost to the onboard charger, thermal management and the battery, and it has to be paid for: without it, electric walks off with an eighth of a range it does not have.
A solar kWh is not free
A kWh from your own system put into the car is a kWh you did not sell to the grid: its cost is the revenue you give up, around €0.10/kWh. It is still by far the cheapest way to charge, but the sum holds up close inspection.
These results are an estimate and depend on the values you enter. They exclude road tax, insurance, servicing and depreciation, which weigh on the total cost of a car and vary a lot between models. The grid CO₂ factor is the conservative one used across the site.