E-Scooter Battery Range Planner
Plan a realistic e‑scooter range (not the brochure number)
This planner estimates how far an electric scooter can travel on a charge using four inputs you can usually find on a spec sheet or measure in an app: battery capacity (Wh), average motor power (W), average speed (mph), and a real‑world efficiency (%) factor. The result is a baseline range under steady, average conditions—use it to decide whether a route is feasible and how much reserve you should leave.
How the calculation works
At its core, range is “energy available” divided by “energy used per hour,” then converted into distance by multiplying by speed.
Step 1: Convert battery energy into usable energy
Battery capacity is measured in watt‑hours (Wh). A 500 Wh pack can theoretically deliver 500 watts for 1 hour. In real riding you don’t get 100% of that energy to the wheel due to controller losses, drivetrain friction, tire losses, and leaving a safety margin. That’s why this calculator applies an efficiency factor.
Step 2: Estimate ride time from average power
If your scooter draws an average of P watts while moving, and you have C watt‑hours available, then estimated ride time is C/P hours (before applying efficiency).
Step 3: Convert time into distance
Distance = time × speed. If you travel at an average speed S (mph), then range in miles is hours × mph.
Formula
Variables:
- C = battery capacity (Wh)
- P = average motor power draw (W)
- S = average speed (mph)
- E = real‑world efficiency (%)
The calculation is:
Where R is estimated range in miles. The same pieces also give estimated ride time:
Ride time (hours) = (C / P) × (E / 100)
Choosing a good efficiency (%)
The efficiency field is a practical “real‑world reduction” knob. Use it to reflect conditions and to build in a reserve. Typical starting points:
- 90–95%: very flat route, warm weather, steady cruising, high tire pressure, light rider, gentle acceleration
- 80–90%: mixed riding (some stops, mild hills), typical commuting conditions
- 70–80%: frequent stop‑and‑go, colder weather, heavier rider/load, rough pavement, headwinds, more hills
- 60–70%: very hilly, strong winds, aggressive riding, cold battery, older battery, or if you want a large safety buffer
Interpreting the results
- Estimated range (miles): A planning number for an average ride. If your commute is close to this value, you should either lower efficiency (more conservative) or plan to recharge.
- Estimated ride time (hours): Useful for planning how long you can stay moving at the chosen average power. If your speed is higher than typical, your effective efficiency may drop because higher speeds often increase aerodynamic drag and power demand.
Practical tip: if you want to avoid arriving at 0%, treat the output as a maximum and aim to use only 70–85% of it (or simply lower the efficiency input until the result matches the reserve you want).
Worked example
Suppose you have:
- C = 400 Wh
- P = 350 W (your typical average draw while moving)
- S = 15 mph
- E = 85%
Ride time:
(400 / 350) × 0.85 = 0.971 hours (about 58 minutes)
Range:
0.971 × 15 = 14.6 miles
If the same route is colder and hillier and you change E to 70%, the estimate becomes:
(400 / 350) × 0.70 × 15 = 12.0 miles
What changes real‑world range the most?
| Factor | What it does | How to reflect it here |
|---|---|---|
| Hills / climbing | Raises average power draw significantly | Increase P if you know it, or lower E |
| Stop‑and‑go riding | Acceleration spikes power; regen (if any) rarely recovers much | Lower E (or increase P) |
| Higher speed | Often increases power demand due to air drag | Don’t just raise S; consider higher P or lower E |
| Cold temperatures | Reduces usable battery energy and voltage under load | Lower E |
| Rider weight / cargo | More energy needed for acceleration and climbing | Lower E (simple approach) or raise P |
| Tire pressure / surface | Rolling resistance changes power required | Lower E for soft tires/rough roads |
| Battery age / health | Reduces effective capacity over time | Lower E or reduce C to a realistic value |
Limitations and assumptions (important)
- Average power is the biggest simplification. Real scooters draw highly variable power (accelerations, hills, starts). If your “average motor power” is an optimistic number, the range will be optimistic.
- Efficiency is a catch‑all. It bundles drivetrain/controller losses, environmental effects, and your reserve margin into one percentage. Two different rides can have the same efficiency for different reasons.
- Speed and power aren’t independent. In real riding, going faster usually requires more power. If you increase speed without adjusting power (or efficiency), you may overestimate range.
- Battery specs can be marketing values. Advertised Wh may not be fully usable (BMS limits, voltage sag, cutoff). Consider using a slightly lower capacity or a lower efficiency to compensate.
- Does not model wind, grade, rider mass, tire size, or aerodynamics explicitly. Those effects must be represented by your chosen power and/or efficiency.
- Not a safety guarantee. Plan conservatively if you rely on the result to avoid being stranded.