Start with loads, not square feet
Two 4,000 sq ft homes can need very different generators: one has a single A/C system and a gas range, the other has three A/C systems, an electric range, a pool and an EV charger. That is why we never assign a kilowatt figure from the size of the house. A load calculation lists every circuit you want on during an outage, adds the starting demand of motors and compares the total with the rated output of each model.
- Essential loads: refrigerator, lighting, outlets, internet, garage door
- Comfort loads: central air conditioning, water heater, range, dryer
- Property loads: pool pump, well pump, irrigation, lift station, EV charger
Air conditioners and starting demand
The compressor of a central A/C system draws several times its running current for a fraction of a second when it starts. That locked-rotor amperage is the single biggest factor in generator sizing in Florida. Soft-start kits and load-management modules reduce the peak or stage the start of a second system, which is how a well-configured 22 kW unit can carry two air conditioners that would otherwise call for a larger generator.
Fuel and rated output
The same generator delivers less power on natural gas than on propane. Every Generac spec sheet lists two ratings, and the load calculation must use the one for your fuel. Natural gas also depends on utility pressure and meter capacity, which we verify before quoting. Propane needs a tank sized for several days of runtime.
22 kW versus 26 kW
Gen-Power installs Generac’s current Next Generation line, where the 22 kW delivers 21 kW on natural gas and the 26 kW delivers 24 kW; a 28 kW model is now the largest air-cooled generator Generac makes. (The previous Guardian Series delivered 19.5 and 22.5 kW at the same sizes; we still service those units.) A 22 kW tends to fit a three- or four-bedroom home with one or two A/C systems, a gas range and load management on the pool pump or EV charger. A 26 or 28 kW tends to fit two or more large A/C systems running together, an all-electric kitchen and laundry, or an owner who prefers not to shed any load.
Larger homes
Estates with three or more A/C systems, elevators, wine rooms or large pool and irrigation equipment usually move to liquid-cooled generators from 30 kW up. They run quieter at full load, are built for long continuous operation and are sized with the same load calculation, often together with a load-management panel that prioritizes circuits.
Get a load assessment
Bring your electric bill, the model numbers of your A/C systems and a list of what you want on during an outage. We measure the panel, confirm the fuel and give you a written proposal with the model, the transfer switch and the assumptions behind the size. No figure on this page replaces that visit.