Generator vs Battery Backup in Central Florida

This is not a brand fight. It is fuel versus a tank of electrons, in a climate where the air conditioner is the load that matters and hurricanes last longer than a dinner outage.

What each machine is for

A home battery stores electricity. Solar can refill it on a sunny day. It starts in milliseconds, makes no exhaust, and needs no weekly exercise run. The tank is small. When it is empty and the sky is dark, you are done until the grid or the sun returns.

A standby generator is a small engine on a pad next to the house. An automatic transfer switch (ATS) senses the outage, starts the engine, and feeds the panel. Runtime is “until the fuel stops.” Natural gas from the street has no tank on your lot. Propane has a tank you fill before the storm. Gasoline in jerry cans is a portable problem, not a standby plan.

A portable generator is a roll-out engine you cord to a few appliances, or (if an electrician installs an interlock) to selected circuits. It is cheaper. You must start it, fuel it, and keep it 20 feet from the house. The U.S. Consumer Product Safety Commission (CPSC) still warns every hurricane season that portables are a leading cause of carbon monoxide deaths after storms. Never in a garage, even with the door up. Never in a porch or carport that traps exhaust.

What they cost in 2026

	Typical installed (Central Florida, 2026)	What you get
One home battery (10-14 kWh)	About $10,000-$16,000	Essentials 1-2 days; limited AC
Two or three batteries	About $20,000-$40,000	Longer essentials, some AC on a sunny recharge day
Portable 5-7 kW + cords / interlock	About $800-$3,000 plus fuel cans	Fridge, lights, maybe a window unit; you are the operator
Standby 10-14 kW (essentials)	About $7,000-$11,000	Selected circuits, maybe one small AC
Standby 18-22 kW (most of a typical house)	About $10,000-$16,000 if gas is already there	Central AC plus the house, until fuel stops
Propane tank (500-1,000 gallon) if no natural gas	Often $2,000-$8,000 extra, more if buried	Days of fuel on site; you fill it before the storm

There is no 30% federal tax credit on a generator you own, and none on a battery you own if it was finished after December 31, 2025. Florida’s 6% sales-tax skip and the property-tax rule (193.624) apply to storage that is part of a solar energy system. A generator is ordinary mechanical equipment. Do not let a solar quote mix the two incentives.

Yearly upkeep: a standby generator wants oil, filters, a load test, and a weekly or biweekly exercise cycle. Budget a few hundred dollars a year, more if you skip it and the unit fails on the first outage. A battery wants a firmware check and a shaded wall. Both need a licensed person if something inside is dead.

Runtime in Florida heat

A 3-ton central air conditioner often draws about 2,400 to 3,500 watts while running, plus a hard start. That is the number that breaks “one battery, whole home” stories. At 3 kW, a 13.5 kWh battery is about four hours of continuous cooling. Fridge, lights, router, and phones without AC are often 4 to 6 kWh per day, so the same battery is closer to two days.

A 22 kW standby unit (about 19.5 kW on natural gas on some nameplates) is in the class that can start a typical central air conditioner and still run the kitchen. It will run tonight, tomorrow, and next week if the fuel is there. Cloudy days do not matter. A flooded street that shuts a natural-gas regulator, or an empty propane tank, does.

Propane sizing, if you go that way: a 500-gallon tank (you only fill to about 80%) is the usual residential size and is often described as several days of a 22 kW unit at a realistic mixed load, not at full nameplate 24 hours a day. A 1,000-gallon tank is the longer-storm bet. Twenty-pound grill cylinders are for a portable, not a whole-house engine.

Natural gas is the cleanest standby story if the pipe is already at the house. Many Central Florida subdivisions have it. Many do not. Look for a gas meter. If there is none, you are buying a tank, a trench, and a gas permit, or you are buying batteries and/or a portable. Do not assume “Orlando has gas.”

Natural gas usually keeps flowing through a hurricane better than the electric grid. It is not guaranteed in a flood or a pipeline outage. Propane on your lot does not care about the street, until you need a refill and the trucks cannot get in.

Safety, noise, and permits

Carbon monoxide. Standby units sit outdoors on a pad with the exhaust aimed away from windows. Portables kill people when they are pulled into a garage “just for the rain.” CPSC: outdoors, at least 20 feet from the house, exhaust away from openings. Put battery-backed CO alarms in the house either way. Newer portables that meet UL 2201 or PGMA G300 can shut off if they sense CO around the machine. That is not permission to run one inside.

Backfeed. Never plug a generator into a dryer outlet to “power the house.” That can electrify the street and kill a lineman. Use a listed transfer switch or a panel interlock installed by a licensed electrician. A battery gateway is the same idea: isolate first, then feed.

Noise. A standby in the 60 to 70 decibel class at the pad is a lawn mower next to the bedroom window. A battery is silent. HOAs care about the first one: setbacks, screening, hours of exercise runs. They care less about a wall-mounted cabinet, though they still may. Florida’s Solar Rights Act (163.04) is about owned solar, not generators.

Permits. A hardwired standby needs building, electrical, and usually gas permits, a site plan, and a load calculation. Orange, Seminole, Osceola, and Lake are not the same desk. A portable used with extension cords typically does not. A portable tied into the panel does. Batteries need electrical permits and a utility interconnection update. Licensed electrical contractor (EC) for the wires. Licensed gas work for the fuel. Same license-check habit as the installer guide.

Solar changes the comparison

Grid-tied solar without a battery or a generator still shuts off in an outage. That does not change.

Solar plus battery: the array can refill the tank on a clear day after the storm. That is the battery’s special trick. Two cloudy days and a 13.5 kWh box still go dark.

Solar plus generator: the generator does not need the sun. If the house also has solar, a well-designed setup can let the panels carry daytime load so the engine idles or shuts off, then the engine covers night and the air conditioner. Many cheap pairings fight each other. Tell both contractors the other machine exists before anyone designs a gateway.

Solar plus battery plus generator is a real design for people who want silent nights most of the year and a week of air conditioning after a named storm. It is also three permits and three maintenance stories. Price it as three line items. Do not hide the generator inside a “complete solar package.”

On Duke Energy Florida and Florida Power & Light (FPL), a battery still does not pay for itself on the monthly bill. A generator never does. Both are insurance. On new Orlando Utilities Commission (OUC) service, a battery can also shift cheap export into evening use. A generator does not. See the Duke vs FPL vs OUC note and the batteries article.

When the generator is the better first buy

• You need central air through a multi-day outage, not a window unit for a few hours.
• Someone in the house depends on power that cannot wait for sun (medical devices, well pump, lots of refrigerated medicine).
• Natural gas is already at the meter, or you will put in a properly sized propane tank and keep it full from June through November.
• You will actually pay for oil changes and the exercise cycle.
• The HOA will allow a pad and the noise.

When the battery is the better first buy

• You already have, or are buying, solar, and you want the array to work when the street is dead.
• Fridge, lights, internet, and phones for a night or two is the actual goal.
• You do not have gas and you do not want a propane tank in the yard.
• Noise, exhaust, and weekly engine tests are deal-breakers.
• You are on new OUC service and you will use stored kWh in the evening on purpose.

When a portable is enough (and when it is not)

Enough: you will store it dry, test it every few months, keep fresh fuel or a propane cylinder plan, run it 20 feet out, and you only need the fridge and some lights. An electrician-installed interlock is safer than a nest of cords.

Not enough: you want the house to take care of itself at 2 a.m., you want central air, you will not haul 50 pounds of machine in the rain, or anyone in the house will be tempted to pull it into the garage “just this once.”

How to decide without a salesperson in the room

1. Write down the outage you are buying for: 6 hours, 2 days, or a week. Florida’s bad ones are the last two.
2. Write down what must stay on. If central air is on that list, one battery is probably not the answer.
3. Look outside for a gas meter. No meter means propane or electricity-only backup.
4. Price a standby and a battery as separate quotes, each with a circuit list, not a monthly payment.
5. If you already have solar, ask each bidder how their machine plays with the existing inverter. If you already have a generator interlock, say so before anyone designs a battery gateway.
6. Check licenses, permits, and HOA in that order. A cheap pad in a setback is an expensive move later.

Buy the generator if the fear is days of 95°F without air. Buy the battery if the fear is a dark fridge and a dead router, or if you want the solar you already paid for to keep working. Buy a portable only if you will treat carbon monoxide as a real rule, not a label on the box. Mixing two of them is fine. Pretending one 13.5 kWh cabinet is a 22 kW engine is how people get surprised in September.