A Battery on the Wall, a Hurricane on the Map

I. Kilowatts, kilowatt-hours, and the air conditioner problem

A battery is rated two ways, and the sales sheet usually blurs them. Power, measured in kilowatts, is how much it can push at one instant. Energy, measured in kilowatt-hours, is how much it holds over time. A common home battery sold in Florida today holds on the order of 10 to 15 kilowatt-hours and can push roughly 5 kilowatts at once, give or take by model. Hold those two numbers apart and most of the confusion clears up.

Central air conditioning is the hard case, and in Florida it is the one you care about. A central air system can draw roughly 3 to 5 kilowatts the whole time it runs, which means a single battery feeding your AC may be flat in a few hours. A refrigerator, a few lights, phone and laptop chargers, and a couple of fans together draw far less, often a few hundred watts on average. That load a battery can carry for most of a day. The picture on the box runs the AC. The battery on your wall probably keeps the food cold.

II. Sizing without fooling yourself

Start with the loads you cannot skip, not the ones you want. A modern refrigerator uses roughly 1 to 2 kilowatt-hours a day. Lights, a well pump if you are on one, a CPAP machine, and chargers add up to something modest. Add those honestly and a single battery of about 13 kilowatt-hours covers the essentials for most of a day, and longer if rooftop solar is recharging it when the sun is out. Storm days are cloudy, though, so count on less solar than a clear afternoon in Fort Myers would give you.

If the air conditioner matters to you, and in a Florida August it reasonably does, you have three honest choices. Wire the battery to a smaller panel that feeds only critical loads (the circuits you truly need), so you never ask it to run the whole house. Buy a second battery and accept the cost. Or keep a fuel generator for the AC and let the battery handle everything quieter and cleaner. Each of those is a real answer. The one answer that fails is expecting one battery to cool a house through a multi-day outage.

III. The rate plans that decide whether it pays

Net metering is the arrangement where the utility credits you for the solar power you send back to the grid, and in Florida it still works roughly as it did before. A 2022 bill that would have phased those credits down was vetoed by Gov. DeSantis, so the rules the Florida Public Service Commission oversees stayed close to where they were. That matters for a battery because what you cannot store, you usually want to sell back at a fair credit.

Time-of-use rates are the other lever, and they are the one people oversell. On a time-of-use plan the price per kilowatt-hour changes by time of day, so in theory you charge the battery when power is cheap and lean on it when power is dear. In Florida the gap between cheap and expensive hours tends to be modest, so the arbitrage savings are usually small. Be clear-eyed: for most Florida homes the real value of a battery is the outage it carries you through, not the few dollars it shaves off a normal month.

IV. Worth watching this month

1. Utilities file Storm Protection Plans (multi-year grid-hardening proposals) with the Florida Public Service Commission on a recurring cycle, so check floridapsc.gov for any open plan or rate docket in your utility's territory.

2. The Atlantic hurricane season runs through November 30, so watch the NOAA National Hurricane Center for anything developing in the Gulf or the Caribbean before you lock in an install date.

3. Watch your utility's tariff pages for any change to residential time-of-use rates, which would shift the thin math on charging and discharging a battery.

4. The federal residential clean energy tax credit that once covered home batteries lapsed for equipment placed in service after the end of 2025, so confirm current IRS rules before you count any credit into the price.

Can a home battery run my central air conditioner?

For a short stretch, maybe a few hours, but not for days. A central air system draws a lot, roughly 3 to 5 kilowatts while running, which drains a single home battery quickly. Most people pair the battery with essentials and keep the AC for grid power or a generator.

How long will a battery last in an outage?

It depends almost entirely on what you run. Fed only essentials like a fridge, lights, and chargers, a typical battery can last most of a day. Rooftop solar recharging it during daylight stretches that further, though storm clouds cut the solar you actually get.

Is net metering still available in Florida?

Yes, roughly as it was. A 2022 effort to phase the credits down was vetoed, so the rules overseen by the Florida Public Service Commission stayed close to where they were. Check your utility's current tariff for the exact credit terms.

Will a battery actually save money on my bill?

In Florida the monthly savings are usually small, because the gap between cheap and expensive hours is modest. The honest reason to buy one is backup power during an outage, not bill arbitrage.