Home Charger Sizing

The average AC power needed to put back the energy you use for driving in the hours the car is plugged in: battery energy = distance × consumption (plus any buffer), energy from the supply = battery energy ÷ charging efficiency, required average power = energy from the supply ÷ charging hours. It then shows how long each common nominal charger rating would take for that energy.

Only if the smaller one cannot replace your energy in the time available. A faster charger does not make the energy cheaper: the cost depends on the kWh drawn and your tariff. Use the EV charging cost calculator for cost.

The vehicle's onboard charger sets a maximum AC charging power. A charger rated above that limit cannot charge faster than the car allows. Enter the limit from the vehicle's specification to see this in the results.

They are nominal ratings on a 400/230 V system: 230 V × 16 A and 230 V × 32 A single-phase, and √3 × 400 V × 16 A or 32 A three-phase (equivalently 3 × 230 V × 16 A or 32 A). Whether any of them is possible at your home depends on your electrical supply, the charger, the vehicle, the installation and local rules. The car does not necessarily receive the nominal power.

Some vehicles can charge from a domestic socket using the manufacturer's cable, usually at a lower power than a dedicated charger. Whether that is suitable for your home and for regular use is a question for the vehicle manufacturer and a qualified electrician; this calculator does not assess sockets or circuits.

The share of energy drawn from the supply that ends up in the battery. The 90% starting value is an example assumption — replace it if you know your vehicle or charger value, for example by comparing the kWh shown by a charger or meter with the kWh added to the battery.