How the calculation works
Energy added = battery size × (target % − current %). Energy drawn from the grid = energy added ÷ (1 − charging loss). Cost = energy drawn × electricity price.
Frequently asked questions
Why can my real cost be higher than the result?
Charging losses, peak-rate tariffs and fast-charger fees all add to the bill. Raise the loss field or enter the price of the charger you actually use.
Can I include public charging fees?
Yes. Enter the public charger’s price per kWh in the electricity price box.