Whole House Generator vs Portable Generator: The Savannah Version of the Question

A portable generator is an engine on wheels. You roll it out, start it by hand, feed it from cans, and connect it either with cords run straight to the appliances or through a transfer switch or interlock an electrician has installed at the panel. A whole house standby is a permanent unit on a pad beside the house, fed from the gas main or a propane tank, with an automatic transfer switch that senses the outage, starts the engine, moves the house over, and moves it back when the grid returns. One is a tool you operate. The other is a system that operates itself.

This is the part of the comparison that belongs to the coast. Savannah, Richmond Hill and the islands are evacuation-zone territory, and when the order comes the house is left to itself. A standby carries it with nobody there: refrigerator, freezer, sump, security, and the air conditioning that keeps a sealed-up house from coming home smelling of mildew. A portable does not get that job. It is never left running unattended, it needs refueling every few hours, and it goes with you or gets stored dry. If the outage you are planning for is the one where you are two hundred miles up the road, the comparison is already over.

A portable keeps a refrigerator cold, a few lamps lit, phones charged, and perhaps one window unit or a set of fans. It will not run central air, and it will not run the well pump, the septic pump and the refrigerator all at once; the storm-week playbook tells portable users to pick two or three loads and decide which cord goes where before the lights go out. A standby is sized to the house from a load calculation, from essentials-only coverage up to the whole panel with the air conditioning included, and the sizing guide walks through the three loads that push a Savannah house up a size.

Georgia Power's storm-safety page is written about portable units, and it is blunt: "Generators produce deadly levels of carbon monoxide very quickly. You cannot smell or see carbon monoxide," and "Never use a generator in a small or enclosed space." A portable's exhaust ends up wherever the machine was set down, so the rules are absolute: well away from the house, pointed away from every door, window and vent, a battery-powered carbon monoxide alarm on the sleeping floor, never in a garage even with the door open. A standby's exhaust is designed into the placement, where the code clearances from windows and doors put it, and its transfer switch removes the other portable hazard entirely: the back-feed through a wall outlet that can electrocute the line crew restoring your street.

A portable is cheap to buy and expensive in attention: fuel stored and rotated, oil changed, a test run before June, cords in a known place, and somebody awake at three in the morning to refuel it. A standby costs more on the day it goes in and asks for one service visit a year plus a weekly self-test it runs on its own; fuel arrives from the main or from the tank. We publish no portable prices, because we don't sell them. What we do publish is what a whole-house generator installation costs in Savannah, by tier, so the comparison can be made against a real number rather than a shelf tag.

Sometimes it is. A rental, a second home you visit twice a year, a budget that cannot stretch this season, or an inland address whose outages have run to hours rather than days can all be served well by a portable used carefully. Where a portable stops being enough is the medical refrigerator, the well pump, the evacuation order, and anyone in the house who cannot manage cords and gasoline in the dark. Those households are the ones this whole site is written for.

Transfer switch — the device at the panel that moves the house between the grid and a generator; automatic on a standby, manual on a portable that has been wired in. Interlock — a simpler panel device that lets a portable feed the panel without back-feeding the street; installed by an electrician, never improvised. Back-feed — current pushed out through a wall outlet onto the utility lines, the hazard the transfer switch exists to prevent. CO alarm — the battery-powered carbon monoxide detector a portable requires on the sleeping floor. Load management — the module that lets a mid-size standby serve a whole panel by shedding big appliances briefly.