Diagnostic guide
How to Choose the Right Standby Generator Size in Florida
Last reviewed · Reviewed by the Pro Electrician technical team
Short answer
To power a standard Florida home including a 3-ton to 4-ton central air conditioner, refrigeration, and lighting, a 20kW to 24kW standby generator is typically required. Larger homes with multi-zone AC systems or pool heat pumps require 24kW to 26kW models.
Starting Wattage Versus Running Wattage
Electric motors, especially air conditioning compressors and well pumps, require two to three times more power to start than to run continuously. A 4-ton heat pump may only consume 4,000 running watts, but its locked-rotor starting draw can spike to over 14,000 watts. Standby generators must be sized to accommodate these momentary startup peaks without stalling.
- Central AC starting wattage often dictates the minimum generator size
- Soft-start modules can reduce compressor starting draw by up to 60%
- Continuous loads like refrigeration, well pumps, and lighting are added to the baseline
Whole-Home Backup Versus Essential Circuit Systems
Homeowners can choose between an essential-circuit system (14kW–18kW) that powers refrigerators, lighting, well pumps, and partial cooling, or a whole-home system (22kW–26kW) equipped with an automatic transfer switch and load shedding that powers every breaker in the residence seamlessly.
Fuel Selection: Liquid Propane Versus Natural Gas
Standby generators run on either natural gas or liquid propane (LP). In rural Hernando County where natural gas is unavailable, buried 250-gallon to 500-gallon propane tanks provide 5 to 10 days of continuous generator runtime during hurricane grid blackouts.
