How to use this calculator
- Enter the battery's nominal energy rating.
- Enter measured power draw while the robot is active and idle.
- Set the share of time expected at active load.
- Protect a battery reserve and compare runtime with the target window.
#3250 · AI & Technology Tool
Robot Fleet Battery Runtime Calculator
Estimate usable operating time for a robot fleet from battery energy, average active power, idle power, active-duty share, and a protected battery reserve. The result helps compare a planned shift with modeled runtime and shows average load, usable energy, and the operating-time shortfall or surplus.
Calculator
Battery and duty-cycle assumptionsFormula
Average power = active power × active share + idle power × (1 − active share)
Usable energy = battery energy × (1 − reserve rate)
Runtime = usable energy ÷ average power
Usable energy = battery energy × (1 − reserve rate)
Runtime = usable energy ÷ average power
What the result means
Runtime is the idealized time until the protected reserve is reached at the entered average load. A positive target margin means modeled runtime exceeds the desired operating time.
Actual runtime can be lower because of battery age, temperature, acceleration peaks, payload, floor conditions, auxiliary equipment, and conversion losses.
Example calculation
A 18 kWh battery with 0.9 kW active draw, 0.25 kW idle draw, 70% active duty, and 20% reserve has 14.40 kWh usable. Its weighted average load produces the runtime shown by the calculator.
Tips for better results
- Use logged average power instead of nameplate peak power when available.
- Increase reserve for battery-life or dispatch requirements.
- Run hot- and cold-temperature cases.
- Include payload and auxiliary equipment in active draw.
- Compare runtime with charging opportunities, not only shift length.
Frequently asked questions
Should I use peak or average active power for the robot fleet?
Use average power measured during representative active work. Peak power is useful for component sizing but usually understates runtime if treated as continuous.
Why is a protected battery reserve removed from usable energy?
The reserve represents energy intentionally left unused to protect the battery or maintain a dispatch safety margin.
Can idle power be zero?
Yes, if the equipment is fully off during non-active time. Otherwise enter standby electronics, communications, and auxiliary loads.
How does active-duty share affect battery runtime?
A higher active-duty share moves average power closer to active power draw, which normally shortens runtime.
Does the estimate account for battery aging and temperature?
No. Reduce the nominal battery energy to the currently usable measured capacity when aging or temperature materially affects performance.
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Battery runtime variables
| Variable | Definition |
|---|---|
| Nominal energy | Battery energy before reserve is protected |
| Active power | Power draw while performing work |
| Idle power | Power draw while waiting or standing by |
| Active-duty share | Percent of time operating at active power |