Your result
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Enter your values, then click Calculate result.How this calculator helps
Estimate charging units, cost and cost per kilometre for an electric vehicle. The calculation keeps important tariff, equipment and usage assumptions visible so visitors can replace defaults with their own bill, datasheet or measured values.
How to use it
- 1
Copy current values from a bill, equipment label, datasheet or measurement.
- 2
Enter realistic operating hours, rates and system losses rather than best-case marketing figures.
- 3
Use the result for comparison and obtain qualified electrical design where safety or installation is involved.
Formula and methodology
Grid kWh = battery energy added ÷ charging efficiency; cost = grid kWh × unit rate.
Uses the values you enter with transparent energy, power and efficiency relationships. Provider tariffs and equipment specifications should be replaced with current figures.
Worked calculation example
Adding 40 kWh at 90% efficiency requires about 44.4 grid units.
How to interpret your result
Use battery energy, charging efficiency and tariff to compare charging with fuel cost on the same travel basis.
Input guide
Use energy actually added rather than battery nameplate alone.
Apply a realistic charging-efficiency loss.
Enter the tariff that applies at the charging time.
Scenario comparison
| Scenario | What it demonstrates |
|---|---|
| 40 kWh battery charged from 20% to 90% | adds 28 kWh before losses. |
| Home versus public charging | compare their different effective rates. |
| Monthly 1,500 km | combine cost with measured vehicle kWh/km. |
Common mistakes to avoid
- Charging the full battery in the calculation after every short trip.
- Ignoring conversion and battery-conditioning losses.
- Comparing charging cost with petrol without matching distance.
Check charger statements or a meter and the vehicle's measured consumption history.
What can affect the result?
Tariffs and adjustments
Provider rates, taxes, fuel adjustments and export rules can change by billing period.
Real operating conditions
Temperature, dust, voltage, cycling, shade and user behaviour change energy results.
Safety and compatibility
Surge, cable protection, equipment limits and installation standards need professional checking.
Limits of this estimate
This planning estimate cannot reproduce every provider bill, inspect a site, certify wiring or equipment, predict weather, or replace a qualified electrical or solar design.
Sources and review information
Frequently asked questions
Is the ev charging cost free?＋
Yes. SolvePilot tools are free, work in your browser, and require no account.
Does SolvePilot store my values?＋
No. Calculations run locally in your browser and the values you enter are not sent to a server.
Should I treat the result as an exact bill or quotation?＋
No. Results are informed estimates. Final charges can vary because of taxes, tariffs, lender terms, usage patterns, or provider rules.
How can I improve the accuracy?＋
Use recent values from your own bill, statement or institution, review every assumption, and confirm important results with the relevant official source.
Is this an official bill or engineering design?＋
No. It is a planning estimate. Confirm tariffs with the provider and safety-critical equipment, wiring and protection with a qualified professional.