The cost of charging an electric car at home depends on the electricity you draw from the grid and the price you pay for it. To start, you don't need an average rate: you need your contract and an estimate of the energy used during the charging session.
The basic calculation: energy times price
Variable charging cost = kWh drawn from the grid × price per kWh. If the charging session spans periods with different prices, calculate each period separately and add the amounts together. Check whether the price you use already includes taxes so you don't add them twice.
A hypothetical example, without promising a market price
Suppose you have a battery with 50 kWh of usable energy and charge from 20% to 80%. The ideal amount of energy added would be 50 × 0.60 = 30 kWh. At an assumed price of €0.20/kWh, that energy would cost €6. This is an illustrative calculation: it is not an electricity offer or a guaranteed final cost.
The energy drawn from the grid may be greater than the amount stored in the battery. If the meter records 33 kWh for that session, at the same assumed price, the variable cost would be €6.60. Use the actual reading when it is available; do not apply a universal percentage for losses.
kW and kWh do not mean the same thing
kW expresses power: the rate of supply at any given moment. kWh expresses cumulative energy. A charger with a higher rated power does not lower the price per kWh or guarantee that the vehicle can accept that power.
As a rough estimate, 30 kWh at a constant power of 7.4 kW takes about four hours. The actual time may be longer due to vehicle limits, available power, and variations in charging. To choose equipment, consult our single-phase and three-phase power guide.
Expenses not included in that calculation
- The cost of the charger and its installation.
- Fixed supply charges or terms.
- A possible change in contracted power.
- Other items on the bill that do not depend on that session.
To compare rates, look at the total cost of your household consumption, not just the charging period. A lower nighttime price may come with other conditions.
Check your estimate over several sessions
Record the energy registered and the calculated cost over several usual charging sessions. If you are comparing data from the car, the app, and the meter, identify what each one measures and avoid treating them as identical figures. This will allow you to adjust the estimate to your usage.
Also read how to schedule charging times. If you are still preparing your charging spot, start with the pre-installation checklist.
From calculation to the right equipment
Compare the specifications of the 7.4 kW single-phase Pulsar Max and the 22 kW three-phase Pulsar Max. Choose based on the vehicle and the installation; a higher rated power does not reduce the price of energy on its own.