Start with a diary, not a leaderboard
Record two ordinary weeks of driving and identify the longest routine day, not just the average. Separate commuting, local errands and occasional long trips. A car that comfortably covers the commute may still need an awkward stop on a weekly family visit. Equally, buying substantial extra battery capacity for one annual holiday may be an expensive way to avoid a modest charging break.
Add your parking situation to that diary. A driver with reliable overnight charging can begin most mornings with a predictable charge level. Someone relying on a public hub must account for the journey to that hub, possible queues and the time spent charging. The same advertised range can therefore support two quite different ownership experiences.
Keep official claims and road tests separate
WLTP is a standardised laboratory-based approval procedure used for European vehicle figures. EPA ratings use a different US testing and adjustment framework. These are useful comparison references within their own systems, but neither is a guarantee for a particular motorway journey. Do not rank one car’s WLTP figure directly against another car’s EPA figure as though the methods were identical.
Independent road tests answer a different question: what happened to a particular vehicle under recorded conditions? Look for air temperature, average speed, route elevation, wind, tyre specification, wheel size and use of cabin heating. A result without that context is weak evidence. This site does not claim to have conducted instrumented road tests; our numerical examples are calculations with disclosed inputs.
Translate energy into a working distance
A first approximation is usable battery capacity multiplied by battery-side efficiency. A 60 kWh usable pack at an assumed 4 miles/kWh gives 240 calculated miles from full to empty. Neither the battery size nor the efficiency assumption should be confused with a tested result. Gross pack capacity can exceed the energy the driver can access, so using the wrong capacity inflates the calculation.
For repeated motorway stops, the relevant window may be much smaller than a full battery. Between 80% and 10%, that same pack provides 42 kWh. At an assumed motorway efficiency of 3 miles/kWh, the calculated distance is 126 miles. This is an illustration of the arithmetic, not a recommendation to arrive with a particular reserve in all circumstances.
| Assumed efficiency | 100–0% arithmetic | 80–10% arithmetic |
|---|---|---|
| 4.0 miles/kWh | 240 miles | 168 miles |
| 3.5 miles/kWh | 210 miles | 147 miles |
| 3.0 miles/kWh | 180 miles | 126 miles |
Allow for winter without inventing a universal penalty
Cold conditions can increase cabin-heating demand and change battery performance. Short journeys can be particularly demanding because the cabin is repeatedly warmed for relatively few miles. Higher road speed, headwinds, rain, gradients, roof boxes and towing can also raise consumption. There is no single percentage reduction that responsibly describes every car and route.
Use a conservative scenario derived from relevant evidence for the model you are considering. Check whether a test vehicle had a heat pump and whether it preconditioned while plugged in. Preconditioning can improve comfort and, where supported, battery readiness; it does not create free energy. Some energy may simply be drawn from the charger rather than the pack.
Compare complete journeys
Range and charging speed should be evaluated together. A car that needs one additional stop can still deliver an acceptable journey if that stop is short, reliable and naturally placed. Conversely, an impressive charging claim is less useful if the compatible site requires a substantial detour or offers only a small number of bays.
For a purchase shortlist, plan one normal week and one demanding trip for each exact variant. Use the same starting charge, weather assumption and arrival reserve. Record driving time, detours, expected charging time and a fallback location. Do not silently replace missing data with a best-case figure. An explicit uncertainty is more useful than a confident but unsupported winner.
Your test-drive checklist
Check the exact wheel and battery specification, reset the trip display with permission, and note temperature and route. A brief test drive cannot establish annual efficiency, but it can expose comfort, visibility and charging-port placement issues that a range chart misses. Ask for the manual’s charging recommendations before signing.
Next: assess the time at the plug