EVKX Range & Travel Calculator

The EVKX Range & Travel Calculator estimates range, energy use and journey time at a chosen driving speed. Use it to compare vehicles under the same conditions or see how a change in speed, heating demand or road surface affects the result.

Open the EVKX Range & Travel Calculator, select the vehicles you want to compare, and choose a mode.

Choose the right mode

• Range: estimates single-charge distance for displayed state-of-charge windows of 100–0%, 100–10% or 80–10%.
• Distance: estimates driving energy, charging stops and total travel time for a chosen distance.
• Time: estimates how far the vehicle can travel within a time budget that includes driving and charging stops.

Start with the same speed and conditions for each vehicle. Then change one input at a time to see its effect. Metric and imperial units use the same calculation model, with converted inputs and outputs.

The charge-window presets belong to Range mode. Distance and Time modes calculate charging strategies separately. Their trip calculation starts with a full battery. For journeys requiring charging, it adds enough energy to cover the calculated shortfall, without an arrival-reserve allowance. There is no setting for a desired arrival charge.

Set the conditions

The selected speed is treated as constant throughout the driving portion. It strongly affects aerodynamic energy demand, so use a speed that represents the scenario you want to compare.

Temperature and heating demand are separate controls. Lowering the temperature changes dry-air density; it does not automatically add cabin heating or model a cold battery. To explore heating demand as well, set the HVAC load separately. HVAC is heating, ventilation and air conditioning, represented here by a constant manual power load from 0 to 5 kW.

The other controls change specific parts of the estimate:

• Road condition applies a rolling-resistance multiplier for dry, damp, wet, very wet or snowy surfaces.
• Battery state of health reduces available energy in Range mode to represent capacity loss with age. Its treatment in Distance and Time modes has a limitation described below.
• Heat-loss factor applies an additional capacity reduction. It is entered as a fraction: 0.20 means a 20% reduction. It is separate from the charging-loss allowance and should not duplicate a capacity loss already represented by state of health.
• Trim selects available wheel and tyre data for the rolling-resistance estimate. Base, Mid and Top select entries in the vehicle's wheel-options list; they do not switch to a complete manufacturer trim with different weight and aerodynamics.
• Trailer presets add trailer mass, rolling resistance, aerodynamic effects and auxiliary demand.

In Distance mode, the terrain controls take total ascent, net elevation change and descent steepness. Total ascent is all the climbing along the journey; net elevation change is the destination's elevation relative to the start. A round trip can have substantial climbing while its net elevation change is zero. The calculation uses these totals rather than a detailed elevation profile.

For calculations based on displayed charge percentages, EVKX uses the energy between displayed 100% and 0% when the reserve below displayed zero is known. Otherwise, it falls back to recorded net capacity, then gross capacity if net is unavailable. If a reserve below displayed 0% exists, using net capacity includes energy outside the displayed window. Gross capacity also includes protected margins. These fallbacks can therefore overestimate the energy available between displayed 100% and 0%. Battery buffer and usable capacity explains these capacity boundaries.

How consumption is estimated

The model combines aerodynamic demand, drivetrain and rolling demand, auxiliary systems and the manual HVAC load. Distance mode can also include the effect of terrain.

Aerodynamic energy per kilometre rises approximately with the square of speed. Its calculation uses air density and the vehicle's drag area, or drag coefficient and frontal area. Rolling demand depends on mass, tyres and road condition. A constant electrical load consumes more energy per kilometre at lower speeds because each kilometre takes longer. Climbing adds energy demand; descending can offset part of it.

EVKX builds the model from vehicle data and calibrates it against available consumption observations. Where suitable measurements are available, their recorded conditions help inform the fit. Otherwise, the model uses valid steady-speed consumption figures, such as 90 km/h, 70 mph and 120 km/h values. WLTP is used as a fallback when no valid steady-speed figure is available.

Missing physical data and sparse consumption observations leave more of the result dependent on default assumptions. The component breakdown is therefore a modelled allocation of consumption, not a measurement of each system in the car. For the wider relationship between battery energy, consumption and certified range, see Understanding EV Range.

Charging and journey time

Distance and Time modes combine the driving-consumption estimate with the vehicle's stored charging curve. The optimiser tests charging windows and numbers of stops to find a low total journey time for the scenario. The selected strategy uses the same charging window at each stop.

Charging-time estimates reduce charger-side power by a fixed 5% to estimate how quickly stored battery energy increases, and add five minutes to each stop. The 5% affects time only; it is not added to driving consumption. Actual losses and stop overhead vary. Charging Loss explains the difference between charger-delivered and stored energy.

Charging stops are calculated positions along the journey. The model assumes a suitable charger is available at each required position and uses the recorded vehicle curve rather than checking a particular station's power limits. Use DC fast charging when planning actual stops around station capability and the energy needed for the next leg.

Read the results

The summary shows the values relevant to the selected mode, including distance, driving energy, consumption, travel time and charging stops.

The consumption chart separates drivetrain and rolling demand, aerodynamic demand, auxiliary systems, HVAC and additional road-condition resistance. A trailer contribution appears when applicable. Terrain affects the trip's consumption but has no segment in the chart. With terrain settings, the chart's total can therefore differ from the consumption shown in the summary.

The chart may label aerodynamic demand as wind resistance. This means drag through still air at the selected speed; there is no separate headwind or tailwind input.

Distance and Time results also include a travel log of the calculated driving and charging segments. The locations shown are distances along the simulated journey, not identified charging stations.

Current limits and route planning

The calculator does not model changing traffic speeds, a detailed route elevation trace, automatic HVAC behaviour or battery temperature. Wet and snowy road settings apply selected resistance assumptions rather than a weather forecast.

Real charger locations, availability, queues, shared power, payment compatibility and prices are outside the core calculation. The model uses the car's curb weight and has no dedicated inputs for passengers or luggage, roof boxes, bike racks or tyre pressure.

Two known issues currently affect results:

• Capacity adjustments in Distance and Time modes: state of health and the heat-loss factor change the reported charging-stop positions and energy added, but the optimiser still uses the unadjusted battery capacity. Stop counts, charging times, journey-time estimates and the distance achievable in Time mode therefore do not consistently reflect reduced capacity. Use Range mode for capacity comparisons.
• Manual recalculation with terrain: changing a terrain input triggers an automatic calculation that includes the terrain settings. The manual Recalculate button currently omits them, so it can produce a different result from the visible settings.

In Distance mode, the optional ABRP panel provides a separate third-party route comparison for vehicles with an available mapping. It does not automatically inherit the EVKX scenario's distance, speed or environmental settings. It opens with a default Nordkapp–Paris route, so set your own route and assumptions in ABRP before comparing its result with the EVKX estimate.