At the pump you see the price per litre and the total. Charging an electric car works differently, but the sum stays simple. All amounts below are examples to calculate with. Real prices differ per charger, per card and per energy contract, and they change regularly.
The basics: kWh times price
Take the number of kWh you add and multiply it by the price per kWh. Add 20 kWh at 0.50 euro per kWh and you pay 10 euro. You’ll find the kWh in the app or on the charger’s screen. Not sure what a kWh is? Read kW vs kWh: charging speed explained.
What else gets added?
Not every charge is that simple. Check in your app or on the charger whether anything comes on top:
- a start fee per charge,
- a monthly subscription for your card,
- a price per minute instead of per kWh,
- an idle fee if you stay parked after charging.
Look at this before you start, especially at a charger you don’t know.
Example: start fee versus kWh price
Say charger A asks 0.45 euro per kWh plus 1 euro per charge. Charger B asks 0.55 euro per kWh and no start fee. Then:
- for 5 kWh, A costs 3.25 euro and B costs 2.75 euro,
- for 10 kWh, both cost 5.50 euro,
- for 30 kWh, A costs 14.50 euro and B costs 16.50 euro.
For a short top-up, the charger with the higher kWh price is cheaper here. For a big charge, it’s the other way round. Work out the break-even point with your own numbers: start fee divided by the difference in kWh price. Here that’s 1 divided by 0.10, so 10 kWh.
Example: paying per minute
With a per-minute price, your bill depends on how fast your car actually charges. Say the price is 0.10 euro per minute and you stay for an hour.
- If your car takes 7 kW, you add 7 kWh. That costs 6 euro, or about 0.86 euro per kWh.
- If your car takes 11 kW, you add 11 kWh. The same 6 euro then works out at about 0.55 euro per kWh.
A slow car, or a nearly full battery that tapers off, makes per-minute pricing more expensive. You can read how tapering works in the charging curve and why fast charging slows down.
Charging at home
At home you pay the kWh price in your energy contract, with no markup from a card provider. Say that’s 0.30 euro and your car uses 18 kWh per 100 km. Then 100 km costs about 5.40 euro at home. At a public charger charging 0.60 euro per kWh, the same distance costs 10.80 euro.
A few things to check:
- Do you have a day and night tariff? Then charging in the cheaper period pays off. That only works if your contract really has that difference.
- Do you have a dynamic contract? Then the price changes per hour or per quarter of an hour. More in charging on a dynamic energy tariff.
- Do you have solar panels? Then the power you generate costs nothing extra, but you do give up what you would otherwise have sold to the grid. How much that matters depends on your contract.
Losses while charging
Some energy is always lost in conversion and in the cables. You pay for those losses too, because your meter or the charger bills the energy that comes out of the grid or the charger, not what ends up in the battery.
Say the loss is 10 percent, an assumption to calculate with. If you want 40 kWh in the battery, about 44 kWh has to go through the meter. At 0.30 euro per kWh that’s 13.20 euro instead of 12 euro. Real figures differ per car and per charger.
Common mistakes
- You compare only the kWh price and forget the start fee. That matters most for short charges.
- You leave the car at the charger after it’s full. An idle fee can make your charge much more expensive, see avoiding idle fees.
- You calculate with the kWh in the battery, not the kWh you pay for.
- You rely on last year’s price. Prices and contracts change, so always check the current terms.
When the sum doesn’t add up
If the price isn’t clearly shown in the app or on the charger, you only find out what you paid afterwards. In that case, pick a charger whose price is visible up front.
Want to know what a trip costs, at home or at a charger? The charging calculator works it out with your consumption and your price. To find your consumption yourself, read calculating consumption in kWh per 100 km. More on the cost structure of the different cards is on charging cards.