Car running-cost budget
Combine recurring vehicle costs into monthly and annual budgets. Choose petrol or electric operation while keeping the other fixed costs.
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EV charging time and cost
Estimate energy, charging time and electricity cost between two battery levels. Use average input power and efficiency on the same billed or metered side.
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Charging time at the assumed average power
5.56hours
Time uses your assumed average power and efficiency; completion time is not guaranteed. Electricity cost includes input energy only, excluding parking and idle fees.
Energy to store in the battery36 kWh
Energy required at the billing input40 kWh
Estimated electricity cost (other fees excluded)200 TWD
Equivalent time in minutes333.33 minutes
Energy stored = usable capacity × (target percent − current percent) ÷ 100. Energy at the billing input = stored energy ÷ efficiency fraction. Time in hours = input energy ÷ average input power measured at the same billing point. Cost = input energy × price per kWh. Equal charge levels give zero time and cost; a lower target is unsupported. Average power and efficiency are your assumptions; the 90% example is not a universal measurement. Do not use a charger's peak as its average or mix battery-side power with meter-side consumption. Power often drops at higher charge levels; temperature, vehicle/charger limits and auxiliary consumption also affect the result. This is not a charging-curve simulation or an on-time completion guarantee. Only per-kWh charges are included; parking, idle, start, time-based, stepped tariffs and installation fees are excluded. Check the vehicle's usable capacity; do not automatically substitute its nominal total capacity.
Method and scope
Stored energy equals usable capacity times the percentage-point increase divided by 100. Input energy divides stored energy by efficiency; hours equal input kWh divided by average input kW, and cost equals input kWh times price.
Equal start and target levels give zero additional energy, time and cost. A target below the current level is not a charging scenario.
Use usable capacity rather than automatically using gross battery capacity, and do not mix battery-side power with meter-side energy. Peak charger power is not the session average; tapering and temperature matter, while parking, idle, session and time-based fees are excluded.
References:Australian energy department: capacity, power, tariffs and charging limitations
What this helps you do
Estimate energy, charging time and electricity cost between two battery levels. Use average input power and efficiency on the same billed or metered side.
What to enter
Start with usable battery capacity (kwh), then fill the other relevant fields in the units shown. The field hints explain the required format and examples.
How the calculation works
Stored energy equals usable capacity times the percentage-point increase divided by 100. Input energy divides stored energy by efficiency; hours equal input kWh divided by average input kW, and cost equals input kWh times price.
Worked example
A 60 kWh usable battery charging from 20% to 80% stores 36 kWh. At 90% efficiency it draws 40 kWh; at 10 kW average it takes four hours, costing TWD 200 at TWD 5 per kWh.
Understanding the answer
Equal start and target levels give zero additional energy, time and cost. A target below the current level is not a charging scenario.
Scope and limitations
Use usable capacity rather than automatically using gross battery capacity, and do not mix battery-side power with meter-side energy. Peak charger power is not the session average; tapering and temperature matter, while parking, idle, session and time-based fees are excluded.