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How to use
- Enter Energy needed kWh.
- Enter Charger power kW.
- Enter Charging efficiency %.
- Calculate, then review units and consumption or cost assumptions before comparing.
How it is calculated
Effective power = charger power × efficiency; time = energy ÷ effective power
Example
Charging 50 kWh with an 11 kW charger at 90% efficiency gives 9.9 kW effective power and about 5.05 hours.
Important notes
Actual charging power can taper near full charge or because of battery temperature and vehicle limits, so real charging time may be longer.
Worked examples and interpreting results
| Case | Calculation | Result |
|---|---|---|
| Effective power | 11 × 90 ÷ 100 | 9.9 |
| Charging time | 50 ÷ 9.9 | 5.050505 |
Frequently asked questions
Does an 11 kW charger always deliver 11 kW?
No. Vehicle limits, charger conditions, temperature and battery state can reduce actual power.
Is the result an estimate or an actual cost?
It is a calculation based on your inputs. Actual prices, consumption and fees can vary by vehicle, route and energy source.
How should two scenarios be compared?
Use the same distance, period and units, and change one variable at a time where possible.