Maine homeowners know the drill. A nor'easter rolls through, the lights flicker, and suddenly you're scrambling for flashlights and wondering how long the food in the fridge will last. Power outages are a fact of life across Portland, Scarborough, and the rest of Southern Maine — and they're not getting shorter. Ice storms, high winds, and an aging grid mean some neighborhoods lose power for days at a time.
The question isn't whether you need backup power. It's which type of generator makes sense for your home, your budget, and your lifestyle. At Goodnow Electric, we install both whole-house standby generators and transfer switches for portable units, so we can give you a straight comparison without pushing you toward the more expensive option.
What Is a Whole-House Standby Generator?
A whole-house (or standby) generator is a permanently installed unit that sits outside your home, connected directly to your electrical panel through an automatic transfer switch. It runs on natural gas or propane and turns on by itself within seconds of detecting a power outage — no manual startup, no extension cords, no hauling gasoline.
Standby generators are sized to power your entire home or specific critical circuits, depending on the model and your electrical load. A typical residential unit ranges from 14kW to 26kW, which is enough to run heating, refrigeration, lighting, well pumps, sump pumps, and most major appliances simultaneously.
What Is a Portable Generator?
A portable generator is exactly what it sounds like — a mobile gasoline- or propane-powered unit that you wheel out of the garage, start manually, and connect to your home through extension cords or a manual transfer switch. Portable units typically range from 3,000 to 12,000 watts and cost between $500 and $2,500 for the unit itself.
They're a solid emergency backup for keeping the essentials running — a few lights, the refrigerator, phone chargers, and maybe a space heater. But they have real limitations that matter during a multi-day outage in a Maine winter.
Head-to-Head Comparison
Here's how the two options stack up on the factors that matter most to homeowners in Westbrook, Gorham, and surrounding communities:
- Automatic operation — Standby generators start within 10-30 seconds of an outage, even if you're asleep or away from home. Portable generators require someone to be physically present to start them, connect loads, and refuel them every 8-12 hours.
- Power capacity — A standby unit can power your entire home. A portable generator forces you to choose which appliances to run and rotate loads throughout the day.
- Safety — Portable generators produce carbon monoxide and must be operated outdoors, at least 20 feet from windows and doors. Every winter, Maine sees CO poisoning incidents from generators used incorrectly. Standby units are permanently installed outdoors with proper ventilation and pose no indoor CO risk.
- Fuel management — Standby generators connected to a propane tank or natural gas line can run for days or weeks without intervention. Portable generators need gasoline, which means trips to the gas station — assuming gas stations have power.
- Cost — This is where portable generators win. A quality portable unit costs $500-$2,500. A whole-house standby generator, including professional installation, typically runs $5,000-$15,000 depending on size, fuel source, and site preparation.
- Home value — A permanently installed standby generator increases your home's resale value. A portable generator in your garage does not.
When a Portable Generator Makes Sense
Portable generators are a reasonable choice if your area rarely loses power for more than a few hours, you only need to keep a refrigerator and a few lights running, you have a tight budget and outages are infrequent, or you rent your home and can't install permanent equipment. Even in these cases, we strongly recommend having a licensed electrician install a manual transfer switch so you can safely connect the generator to your panel without backfeeding the grid — a dangerous and illegal practice that puts utility workers at risk.
When a Standby Generator Is the Better Investment
For most Southern Maine homeowners, a standby generator is the smarter long-term choice. This is especially true if you work from home and can't afford to lose internet and power for days, you have a well pump or sump pump that must run continuously, you have medical equipment that requires uninterrupted power, your home has a smart home system, security cameras, or other connected devices that reset during outages, or you simply want peace of mind during storm season without any manual steps.
We install standby generators from leading manufacturers and handle every aspect of the project — from the concrete pad and gas line coordination to the electrical panel integration and automatic transfer switch. Homeowners across Falmouth, Saco, and beyond trust Goodnow Electric to get the job done right the first time.
Pairing a Generator with Solar
Some of our customers are combining standby generators with solar panel systems and battery storage for a layered approach to energy resilience. Solar handles day-to-day energy production, batteries cover short outages, and the generator kicks in for extended grid failures. It's the gold standard for energy independence in Maine. If you're curious about how solar and generators work together, read our post on planning electrical systems for new homes — many of the same principles apply to retrofits.
What Size Generator Do You Need?
Sizing a generator correctly is critical. Too small and it won't carry the load. Too large and you've overspent on capacity you'll never use. We calculate your home's electrical load based on your panel, your must-have circuits, and any future additions like an EV charger or heat pump. Our generator sizing guide is a great starting point, but a professional load assessment is the most reliable way to get it right.
Ready to Talk Backup Power?
Whether you're leaning toward a whole-house standby or want a transfer switch installed for your portable unit, Goodnow Electric can help. We'll assess your home, walk through the options honestly, and give you a free estimate with no pressure.
Contact us online or call (207) 808-8046 to schedule a consultation. The owner is on every job — you'll always know who's doing the work.