Battery storage

Home battery storage in Florida

Usable capacity and continuous output decide what a battery can carry. Which circuits matter decides the rest.

What does a home battery actually do?

A home battery stores electricity and releases it when you need it, most usefully when the grid is down. Two specifications decide what that feels like: continuous output in kilowatts sets what you can switch on at all, and usable capacity in kilowatt-hours sets how long you can run it. In Florida the first number usually matters more, because air conditioning is the load people actually want and it is a power problem before it is an energy problem.

At a glance

Decides what can run: Continuous output (kW)
Decides how long: Usable capacity (kWh)
Solar alone in an outage: Produces nothing
Largest Florida backup load: Central air conditioning

Capacity and output are not the same thing

Usable capacity (kWh): The size of the tank. Sets how many hours you get from a given set of loads.
Continuous output (kW): The size of the engine. Sets what can be on simultaneously. Exceed it and the system protects itself rather than supplying the load.
Peak output (kW): A short-duration rating covering motor starting surges. It is why a compressor with a modest running draw can still fail to start on an undersized system.

Most battery marketing leads with capacity because it is the larger number. For Florida backup, output is the specification that decides whether the purchase does what you hoped.

Decide the backup scope first

Backup scope drives cost more than the battery brand does, because narrowing it reduces the output requirement rather than merely the runtime. Essential-loads backup is not a smaller version of whole-home backup; it is a different sized machine.

Scope	Typical contents	Effect on the system
Essential loads	Refrigeration, internet, some lighting, medical equipment	Often achievable with a single unit
Essential plus one cooling zone	The above plus a single mini-split	Frequently the best value decision
Whole home	Including central air conditioning and large appliances	Usually multiple units, driven by output

Why solar changes the storage question

A battery on its own holds a fixed amount of energy: when it is empty, the outage continues without you. Paired with solar and configured for backup, the array refills it each day. In a multi-day outage after a storm — the scenario most Florida homeowners are actually buying for — that is the whole difference.

Check a battery against your own loads

Choose what you want running and see whether a given configuration can carry it, and for how long.

Open the backup calculator

Common questions

How long does a home battery last?

Warranties commonly run ten to fifteen years, sometimes with a stated cycle limit. The retained-capacity terms inside the warranty matter as much as the headline year count, so read what the manufacturer actually commits to.

Can I add a battery to solar I already have?

Usually yes. An AC-coupled battery has its own inverter and sits alongside your existing system, which is the straightforward retrofit. A DC-coupled battery generally means replacing or reworking your existing inverter.

Is a battery better than a generator?

It depends on the outage you are planning for. A generator runs as long as it has fuel, which is hardest to obtain after a storm. A battery is silent, automatic, needs no fuel and is useful the rest of the year, but its runtime is bounded unless solar refills it.

Sources

What each source supports on this page, and when we last verified it. Every source we use, with its freshness policy, is listed in the source register.

Powerwall 3 Datasheet
Tesla
Powerwall 3 energy capacity, continuous output, and warranty term.
Verified August 16, 2026
IQ Battery 5P data sheet
Enphase Energy
IQ Battery 5P usable capacity, continuous and peak output, chemistry and warranty.
Verified August 16, 2026
Florida Building Code — high-velocity hurricane zone and wind-borne debris provisions
Florida Building Commission
Wind-load and permitting requirements applying to rooftop solar installations in Florida, including the High-Velocity Hurricane Zone in Miami-Dade and Broward counties.
Verified August 16, 2026