This is an approximate measurement of your cost per charge for your e-bike. The data below uses a 48V, 10.4AH battery as an example. All Data as an example reference, and the actual battery you use shall prevail. Reference data: Battery voltage: 48V Battery Amps/Hour:  10.4AH Local cost per kWh ( kilowatt /hour): 15 cents  To get the estimated cost per charge 1.Multiply your Battery Voltage *  Amps/Hour to get the Watt/hour capacity Example   48V*10.4Ah = 499.2 Wh    2.Then you divide by 1000 to get kilo Watt/Hours Example 499.2Wh/1000 = 0.4992 kWh   3.Now multiply by your average kWh rate  For example, The kWh cost of your local average house is 15 cents per kWh. we get   15 * 0.4992 kWh = 7.488 Cents   Fully charging your 48V 4Ah batterywill costs you 7.488 cents.