EV home-charging cost calculator
Calculate energy drawn from the wall using battery size, charge window, charging losses, monthly frequency, currency, and electricity rate.
Worked calculation
A complete ev charging example
40.3 kWh is drawn from the wall per session before multiplying by six monthly sessions. The inputs are examples, not claims about every device. Replace each one with the label, meter reading, schedule, and tariff that apply to you.
Wall kWh = battery kWh × charge added × (1 + charging loss)60 kWh battery · 20% to 80% · 12% loss · 6 sessions/month
- Monthly energy
- 241.9 kWh
- Monthly cost
- US$43.55
- Annual cost
- US$522.55
Transparent method
The calculation
Wall kWh = battery kWh × charge added × (1 + charging loss)Battery energy is lower than wall energy because charging electronics, battery conditioning, cabling, and heat consume energy.
Read the full methodology →Sensitivity check
Run three scenarios.
Daily top-upUse a smaller charge window with more sessions.
Weekly chargeUse the typical start and target percentages.
Cold-weather caseTest a higher charging-loss assumption.
Use the result well
What can change the answer?
- Public-session fees and parking are excluded.
- Charging losses vary with vehicle, temperature, and charger power.
- Time-of-use pricing should be modelled with the applicable off-peak rate.
Calculation standards
Visible inputs. Reproducible results.
WhoPowerCost Lab's research desk maintains the formulas, market notes, and worked examples.
HowEnergy, tariff, and behavioural assumptions stay separate so readers can replace one input without hiding the others.
WhyThe page exists to answer an operating-cost decision. Advertising never changes a formula, default, or recommendation.