Runtime is the real difference
A natural gas standby generator runs as long as gas flows, which means days of outage with no refueling. A battery gives you silent, instant, maintenance-free power for hours and recharges from solar or the grid. Long winter outages favor generators; short frequent outages and solar homes favor batteries.
Sizing and load management
Whole-home coverage typically needs 18kW to 26kW of standby generation, or a smaller unit paired with a load-shed module that drops the air conditioner or range when demand spikes. Batteries are sized by both kW, how much at once, and kWh, how long.
Transfer switches explained
An automatic transfer switch senses the outage, starts the generator, moves your load over in seconds, then switches back. A manual switch or a generator inlet with an interlock kit is the affordable option for portable units, and it is far safer than extension cords or backfeeding a dryer outlet.
What to back up first
Furnace or boiler controls, refrigerator and freezer, sump pump, well pump, internet, a handful of lights and outlets, and medical equipment. Add air conditioning and the range only if the unit is sized for them.