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Budget backup power for comms and critical safety loads

Comms, alarms, the water pump for firefighting and a few lights must keep running when solar output drops or the main system fails. Size a protected battery reserve for them.

How

1. List critical loads with their watts from maker spec sheets: satellite dish and router, booster, radio chargers, alarm panel, cameras, a few LED lights.
2. Add up the total watts and multiply by the hours you need them to get watt-hours per day.
3. Use the backup runtime calculator in this module to check how long a given battery will run those loads.
4. Ask the power designer to put these loads on a separate critical loads circuit fed from the battery, so they stay on when other loads are shed.
5. For a household without a full solar build, a portable power station can cover these loads (power-29).
6. Keep at least one small portable power bank or solar charger for radios and phones in the grab bag.
7. When grid power returns, unplug sensitive electronics or use surge protection devices, as Ready.gov advises.

Do these first

• power-1

Sources

1. Starlink Product Specifications: Standard. Starlink (SpaceX), accessed 2026-11
2. Power Outage Safety Tips (Ready.gov fact sheet, hosted copy). Ready.gov (FEMA), via Cal Poly Pomona Emergency Management, accessed 2026-11

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