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Standby vs portable: which you actually need
A portable generator and a standby generator solve the same problem in very different ways. A portable is a small machine you roll out, fuel with gasoline, and start by hand. You run extension cords to a few appliances. It is cheap and flexible, but it demands your attention during every outage.
A standby generator is permanently installed and wired into your home. When the power fails, it starts on its own and restores power in seconds. You do nothing. It runs on natural gas or propane, so there are no gas cans and no cords. This is the option most homeowners picture when they say whole-house generator.
Choose a portable if outages are rare and short and you only need to keep a fridge and a few lights alive. Choose a standby if you want automatic, hands-off power for the whole home. If anyone in the house depends on power for medical equipment, or if outages are frequent, the standby is the clear answer.
Sizing it to your home
Sizing is the decision that shapes everything else. It starts with a simple question. What do you want running during an outage? The answer splits into two camps. Essentials-only coverage keeps the critical circuits alive. Whole-house coverage runs the home as if the grid never went down.
Essentials means the well pump, the furnace or boiler, the refrigerator, and some lights and outlets. A smaller generator handles this comfortably. Whole-house adds central air conditioning, electric water heating, and large appliances running at the same time. That demands more kilowatts and a larger fuel supply.
Do not guess at the number. A qualified installer performs a load calculation on your actual home. The load calc adds up your circuits and their startup demands, especially motors like the air conditioner and the well pump. It produces a size backed by data.
Natural gas vs propane
The fuel decision usually makes itself. If a natural gas line already serves your home, natural gas is the easy choice. It feeds the generator directly, so you never refuel and never run out. The supply lasts as long as the utility does, which is ideal for long outages.
Propane is the answer when no gas line reaches your property. You store it in a tank you own and refill. Propane burns clean and stores for years without going stale, which suits rural homes and standby use. The tradeoff is that a very long outage can drain the tank, so tank size matters.
Think about run time, not just the hookup. Natural gas rarely runs dry, though a regional gas disruption could affect it. Propane gives you a known quantity on site, fully under your control. Size the tank for the longest outage you realistically expect. For most homes with gas service, natural gas wins on convenience.
Picking a brand and the transfer switch
Brand matters less for the engine and more for the support behind it. The major standby brands all make reliable units. What separates them is the dealer and service network in your area. A generator is a machine that needs parts and periodic service, so a nearby authorized dealer is worth real weight in your choice.
The automatic transfer switch is the brain of the system. It senses the outage, disconnects you from the grid, and starts the generator. When power returns, it switches you back and shuts the generator down. Match the transfer switch to your coverage plan. A whole-house switch handles the entire panel. A smaller switch covers a chosen set of essential circuits.
Weigh the warranty and the service plan together. Compare the warranty term across brands, and confirm the installer is a factory-authorized dealer, which keeps that warranty valid. Ask how service is handled and how fast a technician can reach you. A strong local service network beats a marginally better spec sheet.
Is a whole-house generator worth it for you
Worth is personal, and it comes down to how much an outage costs you. Start with frequency. If your grid fails often, or storms routinely knock out power for days, a standby generator pays back in comfort and protection. If you lose power once a year for an hour, the case is weaker.
Then weigh what is at stake. A well pump means no power equals no water. A finished basement with a sump pump can flood in a long outage. A home freezer full of food, a home office, or medical equipment all raise the value of uninterrupted power. Climate matters too, since a winter outage without heat is a safety issue, not a nuisance.
Add the quieter benefits. A standby generator can raise resale appeal in outage-prone regions. It removes the scramble for gas cans and cords every storm. For many homeowners the real value is peace of mind, power that simply stays on. If several of these factors apply to you, a whole-house generator is likely worth it.
Common questions
Common questions
The practical details.
Should I get a standby or a portable generator?
Get a portable if outages are rare and short and you only need a fridge and a few lights. Get a standby if you want automatic, hands-off power for the whole home. A standby starts on its own, restores power in seconds, and runs on natural gas or propane. If anyone depends on power for medical needs, choose the standby.
What size whole-house generator do I need?
It depends on whether you want essentials-only or whole-house coverage. Essentials keeps the well pump, furnace, refrigerator, and lights running on a smaller unit. Whole-house runs central air and large appliances at once and needs more kilowatts. A load calculation on your home sets the right size.
Natural gas or propane for a standby generator?
Choose natural gas if a gas line already serves your home, since it never runs dry and needs no tank. Choose propane if no gas line reaches you. Propane stores on site in a tank you own, which suits rural homes but can drain in a very long outage. Size the tank for the longest outage you expect.
Is a whole-house generator worth it?
It is worth it if outages are frequent or long, or if the stakes are high. A well pump, a sump pump, a home freezer, a home office, or medical equipment all raise the value of steady power. Cold climates raise it further, since a winter outage without heat is a safety risk. For rare, short outages, a portable may be enough.
Next step: use the whole-house generator cost calculator to get an itemized, state-adjusted estimate for your project. Last reviewed 2026-08-15.