EV Annual Energy Consumption Calculator

What does this quantity describe?

An electric car's annual energy need follows from distance driven and consumption per 100 km: E = s·e/100. Consumption e is not a fixed vehicle constant — it depends strongly on driving style, speed, temperature and load.

As with fuel consumption in combustion vehicles, an EV's official test-cycle (WLTP) consumption diverges from real-world use. Real-world data shows a typical 10-20% higher figure in mixed everyday driving, with considerably larger gaps at high motorway speeds.

Formula and variables

E = s · e / 100

• E = s · e / 100
• s = 100 · E / e
• e = 100 · E / s

Choose the inputs correctly

Enter two of the three quantities. Annual energy requires mileage and consumption, mileage requires energy and consumption, consumption requires energy and mileage. Use a real, self-measured value for e where possible rather than the pure manufacturer figure.

How to use the calculator

Select the target quantity and enter the two known values with units. For a more realistic annual energy estimate, add roughly 10-20% to the vehicle's WLTP figure to account for everyday conditions.

Worked example

Given s = 15,000 km and e = 20 kWh/100 km, substitution gives E = 15,000 · 20 / 100 = 3,000 kWh per year.

Understand the result and units

An annual energy need of 3,000 kWh is the amount that must be charged over a year to cover the assumed mileage at this consumption — excluding charging losses, which additionally increase the amount drawn from the grid.

Consumption is given in kWh per 100 km, energy in kWh, larger amounts also in MWh. Consumption rises disproportionately with speed, since aerodynamic drag grows with the square of speed.

Typical applications

The calculation is used to estimate annual electricity costs for EVs, compare models, size home wallboxes and PV self-consumption scenarios, and for rough charging-infrastructure planning.

Assumptions, limits and common mistakes

The formula assumes a constant average consumption over the year. Real values vary with outside temperature (especially in winter due to cabin heating and lower battery efficiency), driving profile, load and tyre choice; charging losses during the charging process itself are not included here and would need a separate charging efficiency factor.

Common mistake: Do not take WLTP consumption figures uncritically as real-world consumption — real-world data typically shows 10-20% higher values in everyday use, and considerably more at high motorway speeds. Also, do not confuse vehicle consumption (kWh at the vehicle) with grid consumption (kWh from the outlet, including charging losses).