Inputs
Example data table
| Scenario | Speed (km/h) | Temp (°C) | Adjusted (kWh/100km) | Range (km) | Range (mi) |
|---|---|---|---|---|---|
| Eco city commute | 45 | 18 | 14.1 | 345.1 | 214.4 |
| Normal mixed trip | 85 | 22 | 21.9 | 275.4 | 171.2 |
| Sport highway cold | 115 | -5 | 65.3 | 89.9 | 55.8 |
Formula used
Eusable = Epack × usable% × (1 − reserve%) × (1 − degradation%) × Tenergy
Tenergy reduces accessible energy in very cold or hot conditions.
cprop = cbase × (w·Mroll + a·Maero + o·1) × Mcycle × Mstyle × Mtemp × (1 − Sregen) ÷ η
Shares w,a,o depend on city/mixed/highway. Maero scales with relative air speed squared.
caux = (Paux / v) and celev = (m·g·Δh / 3.6e6)
For net descents, downhill recovery is limited by the regen setting.
Range = Eusable / (cprop + caux + celev)
How to use this calculator
- Enter your pack capacity and a realistic base consumption from past trips.
- Set average speed and expected wind; these dominate aerodynamic losses.
- Add temperature and cabin setpoint to estimate HVAC energy per kilometer.
- Include payload, road condition, and tire pressures for rolling losses.
- Use advanced multipliers if you have measured data or modifications.
Battery energy window
Range starts with usable energy, not gross pack size. Packs often expose 90–97% of capacity, and drivers keep a buffer for routing risk. Here, usable kWh equals pack capacity × usable percent × (1 − reserve) × (1 − degradation), with a temperature availability factor. Example: 75 kWh, 94% usable, 10% reserve, 6% degradation gives ~59.6 kWh before temperature effects. Many owners use a 10–90% window.
Baseline consumption calibration
Base consumption is the best anchor because it captures drivetrain efficiency, tires, and route texture. Use the median kWh/100 km from mild-weather trips, then layer adjustments. Many midsize EVs run 14–19 kWh/100 km in mixed use, while larger SUVs often sit 18–24. A realistic baseline reduces reliance on extreme multipliers. A 10% mass increase or low tire pressure can raise rolling losses noticeably.
Aerodynamic and speed effects
Above ~70 km/h, aerodynamic drag dominates. Drag power scales with air speed³, while energy per kilometer tracks roughly air speed² when other terms are steady. A 10 km/h increase at highway speeds can cut range quickly. Headwinds compound losses: a 20 km/h headwind at 100 km/h raises relative air speed to 120 km/h, increasing aero losses by about (120/100)² ≈ 1.44. Roof racks and low tire pressure further worsen highway efficiency, so use the aero multiplier for add-ons.
Temperature, HVAC, and auxiliaries
Cold weather reduces accessible energy, and cabin heating can add several kilowatts. The calculator converts auxiliary power to distance using Paux / speed, so slower driving makes HVAC costlier per kilometer. Rule of thumb: 2 kW at 40 km/h adds 5 kWh/100 km, but only 1.7 kWh/100 km at 120 km/h. Heat pumps typically lower winter HVAC power versus resistive heaters, so adjust auxiliary input accordingly.
Elevation, regen, and planning buffers
Climbing consumes m·g·Δh energy; descending recovers only part via regenerative braking. With 60% regen, a 1,000 kg effective mass descending 100 m might return ~0.16 kWh, while the climb costs ~0.27 kWh. Reserve and degradation are practical buffers: 5–15% reserve is common on sparse corridors, and increasing degradation keeps estimates realistic as packs age. A 1–3% annual capacity fade is a useful starting assumption for older vehicles.
FAQs
How is the estimated range calculated?
The tool divides usable battery energy by total energy per distance, combining propulsion consumption, auxiliary loads, and net elevation cost. Multipliers adjust for speed, wind, temperature, driving style, road condition, and drivetrain efficiency.
What should I enter for usable battery percent?
Use the portion of the pack that is typically accessible for driving. If you are unsure, start with 94–96% for many modern packs, then adjust so the calculator matches a known full-charge trip.
How do I choose base consumption?
Use your vehicle’s recent average kWh/100 km from mild-weather driving with typical payload. Pick a median value rather than a best-case run, then tune speed, wind, and HVAC inputs to match a specific trip.
Why does wind change range so much?
Aerodynamic losses rise with the square of relative air speed. A headwind effectively increases your speed through the air, so energy per kilometer can jump quickly even if your ground speed stays the same.
How do I account for battery aging?
Set degradation to reflect reduced capacity over time. If you do not have a measured value, try 1–3% per year as a starting point, then refine using your observed usable kWh between charge limits.
Does regenerative braking increase highway range?
Regen helps most in stop-and-go or hilly routes where you frequently decelerate. On steady highway cruising there is little braking to recover, so high speed and wind still dominate overall energy use.