Preparedness · not a product test
Battery backup for hurricanes and multi-day outages
A battery is silent and indoor-safer than a gas generator. It is also finite. Plan loads and recharge, not just kWh on a box.
Sizing without folklore
Use the calculator. A useful planning split:
Essentials (start here)
Fridge, a few lights, internet, phones, CPAP, maybe a window AC or furnace fan. Average often 0.3–1.6 kW if you are strict. A 4 kWh portable can cover a night; a 12 kWh stack can cover a calm day.
Whole-home through a storm week
Needs 20–40+ kWh or daily solar/generator recharge. Central AC will empty almost any single-wall battery in hours. That is arithmetic, not a brand failure.
Placement and code-level common sense
- Keep wall batteries and inverters above expected flood level. Manufacturers specify indoor/outdoor ratings — believe the IP rating, not a blog photo.
- A critical-loads subpanel is more useful than a bigger battery you will waste on a pool pump.
- Portables belong indoors dry, with cables run so garage doors and exhaust are not an issue. They are not generators; they also are not waterproof.
- A transfer switch or interlock is still the safe way to feed house circuits. Do not backfeed a dryer outlet.
Charge plan
T-48 to T-24 hours: charge every battery to 100% from the grid while it still exists. EcoFlow documents a Storm Guard–style auto-charge on Ultra X. Tesla documents Storm Watch. Use them if you have them.
During: shed HVAC first. A fridge cycling plus CPAP is a small, high-value load.
After: portable solar (EcoFlow lists a 400 W folding panel at $549) only helps in sun. After a hurricane the sky is often useless for 24–48 hours. A small inverter generator as recharge — not as the primary house feed — is a common hybrid. Follow CO rules.