How it is calculated
- Single-phase power = voltage × current ÷ 1,000.
- Three-phase power = √3 × voltage × current ÷ 1,000.
- Delivered energy assumes 90% charging efficiency; estimated range = delivered energy ÷ consumption × 100.
07 · Home charging
Estimate home charging power and range
Translate electrical supply values and available charging hours into nominal power, battery energy and potential driving range. Use it to understand the arithmetic before discussing equipment with a qualified installer.
Your inputs
Get your result
Use your own figures or load the worked example below. All calculations stay in this browser.
This estimate does not assess electrical capacity or installation suitability. Actual power is limited by the circuit, charger, and vehicle.
How to use this tool
- Select single phase or three phase and enter the appropriate voltage and current per phase.
- For three phase, use line-to-line voltage, such as 400 V, rather than a 230 V phase-to-neutral value.
- Set hours and vehicle consumption, then calculate. Apply the lowest limit of your circuit, charger and vehicle.
Worked example
400 V, 16 A three-phase charging
- Supply voltage (line-to-line for 3-phase)
- 400 V
- Current
- 16 A
- Supply type
- Three phase
- Charging window
- 8 hours
- Vehicle consumption
- 18 kWh / 100 km
Expected result About 11.1 kW · 79.8 kWh over 8 hours · about 443 km
√3 × 400 × 16 ÷ 1,000 = 11.085 kW. Over eight hours at 90% efficiency this is 79.81 kWh, equivalent to 443.4 km at 18 kWh/100 km.
Transparent estimates
How to read this result
Nominal power assumes a balanced supply and power factor of one. Energy is not capped by battery capacity or the car's onboard charger; a full battery stops charging. This is not an installation assessment.
Assumptions
- Voltage and current are treated as steady nominal values for the full charging window.
What this estimate cannot tell you
- This is not an electrical installation or safety assessment. Vehicle, charger, circuit, and supply limits may cap power.