Generator size is measured in kilowatts (kW). Too small and it trips or can't start your air conditioner; too big and you've overpaid. The right size depends on what you want to keep running.
Two common approaches
- Essential circuits: refrigerator, some lights, outlets, Wi-Fi, a gas furnace fan, maybe a window unit. Smaller generator, lower cost.
- Whole home: everything, including central air. Larger unit, sometimes paired with load-management so big appliances take turns.
Central air is the big one
In Louisiana, keeping the AC running is usually the reason people buy a standby generator. An AC compressor draws a surge of power when it starts, so the generator has to be sized for that surge, not just the running load. Soft-start kits can help.
Get a load calculation
A good installer will walk through your panel and appliances and do a load calculation before recommending a size. Be cautious of anyone who quotes a size over the phone without asking about your AC, range, water heater, and pool equipment.