Compressor cycling and startup surge matter more than label watts.
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emergency power planner
Emergency Power Plan Builder
Turn outage essentials into a printable battery plan with load checklist, runtime target, solar offset, reserve, surge checks, and source-backed model starting points.
Multi-load checklistFridge, router, lights, phones, CPAP, Starlink, fan, and pump.
Solar offset includedDaytime recharge is separated from stored battery capacity.
Printable planCopy or print the result before a storm or outage window.
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Recommended station size
6,930 Wh+Recommended station size: 6,930 Wh+Includes 85% AC efficiency, 20% reserve, and a 15% planning buffer after solar offset.
Load energy4,488 Wh
Solar offset390 Wh
Running watts572 W
Startup surge2,900 W
Conservative7,970 Wh+
Estimated6,930 Wh+
Optimistic6,237 Wh+
Conservative assumes harder conditions; optimistic assumes favorable conditions.
Count ONT, modem, router, and mesh nodes separately if needed.
Use the total number of bulbs or lamps you expect to run.
Charging is usually intermittent, not a 24-hour steady load.
Use manufacturer guidance for medical backup decisions. This is a comfort-focused estimate, not medical advice. Use the device manufacturer's battery guidance for critical backup planning.
Power path, cable, heat, and sky view can change real draw.
Use lower hours if you can charge once and work from battery.
Keep it separate from the router so its steady draw is not missed.
Set quantity to the number of mesh nodes that must remain powered.
Brightness, size, refresh rate, and panel type change real draw.
Small fans can become important in warm-weather outages.
What To Check Next
Source-Backed Model Starting Points
These are formula-fit starting points from the local model database, not affiliate rankings.
Zendure SuperBase V6400
6,438 Wh, AC output 3,800 W, confidence Verified.
- capacity short by 492 Wh
EcoFlow DELTA Pro Ultra
6,144 Wh, AC output 7,200 W, confidence Verified.
- capacity short by 786 Wh
Goal Zero Yeti 6000X
6,071 Wh, AC output 2,000 W, confidence Verified.
- capacity short by 859 Wh
Emergency and medical-adjacent loads need conservative planning. This tool is a planning estimate, not a safety guarantee. Check device labels, manuals, local guidance, and manufacturer backup instructions.
WattRunTime.com
WattRunTime emergency power plan
Recommended station size
6,930 Wh+Includes 85% AC efficiency, 20% reserve, and a 15% planning buffer after solar offset.Load energy4,488 Wh
Solar offset390 Wh
Running watts572 W
Startup surge2,900 W
Outage target
24 hours
Loads
- - Full-size refrigerator: 1 x 500 W, 33% duty, 24 active hours
- - Router or modem: 1 x 12 W, 100% duty, 24 active hours
- - LED lights: 3 x 10 W, 100% duty, 6 active hours
- - Phone charging: 2 x 15 W, 100% duty, 2 active hours
Emergency and medical-adjacent loads need conservative planning. This tool is a planning estimate, not a safety guarantee. Check device labels, manuals, local guidance, and manufacturer backup instructions.
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How To Use The Plan
Start with essentials first. Add comfort and work loads only after the refrigerator, communication, medical-adjacent, and lighting assumptions are realistic.
Critical loads
Refrigerators, pumps, and medical-adjacent devices need conservative surge and reserve checks before comfort loads are added.
Solar offset
Solar reduces daily Wh demand, but overnight backup still depends on stored capacity and weather conditions.
Model fit
Candidate stations must clear capacity, AC output, and known startup surge before appearing as starting points.