Driving & travel · Calculator companion · By K Imports
EV journey & charging: practical guide
This guide explains how to use the Count.ie ev journey & charging. Estimate range, charging loss and day/night electricity cost. Follow the inputs, method and worked example below, then compare your own scenario.
Guide written .
Open the EV journey & charging calculatorWhat to prepare
- Record the distance, vehicle specification and the relevant fuel or electricity price.
- Separate one-off purchase or import costs from recurring running costs.
- Use observed consumption where available and label any manufacturer's figure as an assumption.
Understand the inputs
- Real-world consumption uplift (%)
- Set to zero when using measured real-world consumption.
The calculation method
Battery energy = distance × Wh/km ÷ 1,000. Grid energy divides by charging efficiency. Day/night prices use the selected energy split.
Worked example
Illustrative inputs and their result.
Example inputs
- Journey distance (km)
- 150
- Usable battery capacity (kWh)
- 64
- Baseline energy use (Wh/km)
- 180
- Real-world consumption uplift (%)
- 0
- Share of grid energy lost (%)
- 15
- Day electricity price (€/kWh)
- 0.35
- Night electricity price (€/kWh)
- 0.15
- Charging energy at night (%)
- 80
Calculated example result
- Charging cost for the journey
- €6.04
- Electricity from the grid
- 31.765 kWh
- Estimated range
- 355.56 km
- Cost per 100 km
- €4.02/100 km
How to interpret the result
A running-cost or range estimate is not a guarantee of real-world performance. Weather, loading, driving conditions, charging losses and changing prices can alter the result.
Compare vehicles over the same distance and ownership period. Test a higher energy price or worse consumption before deciding that the apparent saving is dependable.
Common mistakes to avoid
- Do not mix litres per 100 km with miles per gallon, or battery capacity with energy purchased.
- Distinguish an advertised charging power from power sustained during a full session.
- Check taxes, vehicle classification and exclusions against the stated date and sources.
Assumptions and sources
A 15% energy loss means dividing by 0.85, not merely adding 15%. Weather, speed, reserve charge and battery health affect range. Tariff standing charges and session fees are excluded.
If your case falls outside this scope, use a more suitable calculator or contact us about an unclear method.