Portable Power Station Runtime Calculator
Estimate portable power runtime from usable capacity, conversion efficiency, standby watts, load duty cycle, and a user-selected reserve.
Estimated runtime
Run the calculator
Planning estimate only: replace the example defaults with measured load values and exact equipment documentation. Standby must be lower than calculated battery-side running draw. Verify starting surge and recharge separately; this tool does not establish medical suitability or guarantee runtime.
- Usable watt-hours
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- Battery-side average power
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- Raw runtime before reserve
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- Planned runtime after reserve
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Conservative runtime scenarios
Compare the entered load with harder duty-cycle assumptions
Example defaults only — replace them with measured values and exact equipment documentation. Outputs are rounded down to the nearest tenth-hour or whole minute. Starting surge is a separate pass/fail check, and recharge is not included in these runtime outputs.
Planning workflow
How to estimate portable power station runtime for outage loads
- Enter the power station watt-hour rating and an exact-model usable-capacity assumption.
- Add measured running load watts, conversion efficiency, and battery-side standby draw.
- Enter a measured or documented duty cycle and select energy to hold as reserve.
- Compare entered, higher-duty, and continuous-load scenarios, then check starting surge separately.
- Test the exact setup and treat recharge, medical-device requirements, and fuel-generator safety as separate planning checks.
Evidence for the assumptions
Sources behind the runtime planner
- Home Use Devices: How to Prepare for and Handle Power Outages for Medical Devices that Require ElectricityU.S. Food and Drug Administration
- DELTA 2 User ManualEcoFlow
- Explorer 1000 Plus Portable Power StationJackery
- CPSC Generator Safety and Carbon Monoxide WarningU.S. Consumer Product Safety Commission
Frequently asked questions
Does watt-hour runtime include starting surge?
No. Runtime math uses running watts. Verify inverter surge rating separately for refrigerators, pumps, or compressors.
How much usable capacity should I assume?
Use documented settings and test results for the exact power station and battery configuration. Do not treat the label watt-hours as automatically deliverable energy.
Can this calculator size medical backup power?
It can help estimate energy, but medical users should check device manuals and clinician or provider guidance before relying on any battery.
Essential load presets
Use measured watts whenever possible
Solar recharge reality check: panel input depends on the power station's documented limits and actual conditions. Treat recharge as a separately measured scenario, not free energy inside the runtime estimate.
Do not size from watt-hours alone
Check starting surge, AC vs DC efficiency, pass-through charging limits, safe indoor use, carbon monoxide rules for generators, and whether a medical device needs provider guidance.
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