Florida generator guide

What 'Whole-Home Generator' Actually Means (and Why the Phrase Is a Trap)

You'd think a bigger house needs a bigger generator. So why can a 5,000-square-foot place down near the coast run fine on a 24kW, while a 2,700-square-foot home up in the mountains needs a bigger unit than that? Same brand. Same "whole-home" sticker on the box. It turns out square footage has no idea what's plugged into your house — and "whole-home" was never a size to begin with.

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"Whole-home" is a promise, not a measurement

Here's the thing nobody says out loud at the sales table. "Whole-home generator" describes a goal, not a specific machine. It means the thing is supposed to run your whole house instead of just a few circuits. It does not tell you a single number about whether it'll actually pull that off in your house.

The box says "whole house" the way a bag of chips says "family size." Which family? Whose house? Two homes on the same street can both buy the exact same model and get completely different results, because the generator doesn't power square footage. It powers whatever's actually running when the lights go out.

So the phrase is doing a lot of quiet work. It sounds like a spec. It's really just a marketing category — and if you shop by that label alone, you're shopping blind.

Square footage lies. Here's what's really deciding your size

A generator doesn't see your floor plan. It sees your loads — the stuff that draws power. And the single biggest thing that decides how much power your house pulls isn't how big it is. It's whether your heat and your big appliances run on electricity or on gas.

That's the whole trick behind the coastal house versus the mountain house. A lot of Florida homes heat with a gas furnace, cook on a gas range, dry clothes with gas, and heat water with gas. So the only real electric monster in the house is the air conditioning. Big house, but a surprisingly polite electric appetite.

Now take the smaller mountain home. All electric. It heats with electric resistance or a heat pump leaning on electric backup, and heating a house with electricity is one of the hungriest things a home can do — it's like leaving four hair dryers running all winter. Smaller house, way bigger draw. That's why the little place needs the bigger unit and the big place doesn't. Square footage never even entered the conversation.

In Florida there's a wrinkle on top of it: a lot of homes don't have a natural gas line at all, so "gas" appliances mean propane from a tank in the yard, and plenty of houses are fully electric whether the owner realizes it or not. Which is exactly why you can't eyeball this from the curb.

Why a "smaller" generator can still run everything

This is where it gets genuinely useful. Modern standby units can play traffic cop with your big loads. Instead of trying to power the AC and the electric dryer and the oven all at the same exact second, a smart load-management setup just makes them take turns.

Think of it like a bouncer at a club with one door. When the air conditioning walks in, the dryer waits outside until the AC's done. You never notice, because who's drying towels during a hurricane anyway. That's how a 24kW can quietly cover a house the old math said needed something bigger — it's not powering everything at once, it's powering everything you'd actually use at once.

And there's a matching gotcha people trip on. A 24kW unit puts out roughly 100 amps at your home's normal voltage, and folks see that "100" and panic because their panel says 200. But your panel almost never pulls its full rating. That 100 amps is the whole lived-in load of most homes with room to spare. The number on the panel is the ceiling, not the rent.

All of which is to say: the size on the box and the coverage you get are two different questions. The only way to connect them is to add up what's really in your house — the AC tonnage, the heat, the water heater, the range, the well pump if you've got one — and size to that. Not to a floor-plan number a builder wrote down years ago.

So how do you find your number?

You've probably noticed the pattern by now. Every honest answer to "what size do I need" ends in "it depends on your house." Which is true, and also completely useless when you're just trying to figure out what this is going to cost you.

That's the part GENERasic is built to skip past. Instead of a range, a ballpark, or a "well, somewhere between this and that," you give your actual address and get one committed price to have the right-sized system installed at that specific home — the number that already accounts for your loads, your fuel, and the run of pipe and wire your house actually needs.

Same idea the whole article's been circling: your house is the spec, not the label on the box. Pull your price for your address, and you'll finally see the one number that means anything — what it costs to keep your lights on.

Common questions

When the power goes out, how long before the generator kicks in?

Seconds — usually somewhere around ten to twenty. A standby unit watches the utility line through an automatic transfer switch, and the moment it senses the power's gone, it starts itself and takes over. You'll flicker dark for a breath, then you're back. When the utility comes back on, it switches your house back to the grid and keeps running a little longer to cool itself down before shutting off.

It says 24kW but the output is only about 100 amps — is that enough to run everything?

For most homes, yes. That 100 amps is at your home's standard 240 volts, and that's a lot more house than it sounds like. Your panel might be rated for 200 amps, but almost no home actually draws its full panel rating at once — that's the ceiling, not what you use. The real question isn't the amp number, it's what's running at the same time, which is exactly what load management is there to handle.

I've got a 3,000-plus square foot all-electric house and I want to run everything. What size do I need?

All-electric is the phrase that changes the answer. When your heat, water heater, range, and dryer all pull from the panel, your draw is far higher than a similar-sized home running gas for those — so all-electric homes tend to need a larger unit, and load management to let the big items take turns. Square footage won't get you there. Adding up your actual electric loads will, and that's what a real sizing at your address is for.

What size propane tank should I get with it?

It comes down to how long you want to run without a refill. If your home has natural gas piped in, there's no tank at all — it runs as long as the utility gas holds, which is basically forever in a storm. On propane you're limited by the tank, and since a lot of Florida homes don't have gas lines, plenty of owners go with a larger buried tank so a multi-day outage doesn't leave them rationing fuel. The right tank pairs with the size of the unit and how long your area tends to lose power.

I've heard an air-cooled unit is on borrowed time after running a full week straight. True?

It's not that it quits — it's that it needs you. An air-cooled standby is built to run through a long outage, but like any engine it wants maintenance on a schedule: check the oil after the first full day of running, then plan an oil change a couple days into a long haul. Skip that and you're asking for trouble. Homes that expect to run for many days on end sometimes step up to a liquid-cooled unit built for marathon duty, but for the outages most Florida homeowners actually see, an air-cooled unit that's been maintained will carry you fine.

Stop reading ranges. Get your number.

GENERasic pulls the real property, flood, and elevation data for your exact address and returns one all-in installed price — sized to your home, your fuel, and your flood elevation. The vetted local installer confirms it on site.

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