Wallbox basics: 11 kW, 22 kW and what your car can actually take
The wallbox offers the power. The car decides how much of it to take.
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EV charging time and cost calculator
Work out how long an electric car takes to charge at home or on a fast charger, what it costs and how much range you add, including solar power.
How the calculation works
On AC, the charging power is the lower of the charging point and the car's onboard charger, and stays nearly constant until about 95 percent. On DC, power is modelled as full up to 50 percent, then tapering to less than half by 80 percent and lower still towards 100 percent, a typical shape for current cars. Real curves vary by model, battery temperature and charger.
- Losses between meter and battery: 15 percent on a household socket, 9 to 11 percent on a wallbox, 6 percent on DC.
- Solar power is valued at the feed-in tariff you give up by charging the car instead.
- Range added uses the consumption you enter; winter and motorway driving raise it noticeably.
Background
All calculatorsGuides to go with it
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