What are the two main ways to set up a home generator?
A standby generator sits on a pad outside the house and usually runs on natural gas or propane. When utility power fails, an automatic transfer switch disconnects the house from the grid and starts the generator. When power returns, it switches back and shuts the generator down.
A portable generator connection uses an inlet box on the outside wall plus a manual transfer switch or a panel interlock. You wheel the generator out, plug one cord into the inlet, and turn on the circuits you want.
The standby route is more expensive and hands-off. The portable route costs much less and works well if someone's home to run it.
What does a standby generator installation involve?
- A load list. Decide what has to run in an outage: the heat pump or furnace blower, refrigerator, well pump, sump pump, medical equipment, or the whole house. That sets the generator size.
- Placement. The unit needs a level pad and clearance from windows, doors, and vents. On a sloped Knox County lot, finding that spot can take some site work.
- Permits. The electrical side needs a permit from the city, county, or state office for your address. The gas hookup has its own requirements.
- Transfer switch. It goes in beside or in place of the main panel, and the generator is wired to it.
- Fuel. A licensed gas fitter or plumber connects natural gas or propane. Call 811 before any trenching.
- Testing and inspection. The system is tested by cutting utility power, then inspected.
Who should consider a generator in Knoxville?
A generator deserves a serious look if:
- A past outage cost you, through spoiled food, a flooded basement, or days of missed work
- Someone at home relies on power for oxygen, a CPAP, or other medical equipment
- A sump pump keeps your basement dry in heavy rain
- You work from home and can't lose several days
- Your home is on a well, so no power means no water
- You've been running extension cords from a portable generator through a cracked window
East Tennessee outages can be big. In August 2023, storms and a tornado left about 60,000 KUB customers without power, which KUB said ranked among the top five outage events in its history, WVLT reported. Ice and wind in January 2026 caused more outages across West and North Knoxville and the surrounding area, according to WVLT. Homes at the end of long rural lines, like parts of Corryton and rural Blount County, can wait longer for crews to reach them.
Why does a generator need a transfer switch?
A generator wired into the house without a transfer switch can push power out through your meter and onto the utility lines. That's called backfeeding. It can electrocute a lineworker who thinks the line is dead and endanger neighbors, and it can damage the generator and your wiring when utility power returns.
KUB's power outage guide says never to connect a generator to your home's main wiring, warns that power can flow back into the lines, and says generators should be installed and inspected by licensed electricians. A transfer switch or a panel interlock solves this, because the house can be connected to the utility or to the generator, never both at once.
A "suicide cord" that plugs a generator into a dryer or wall outlet skips that protection and is never safe. If you already own a portable generator, an inlet box and a transfer switch or interlock is the right fix.
KUB's guide also warns that generators produce deadly carbon monoxide. Run them outside, away from windows and doors, and never in a garage, even with the door open.
What affects the cost of a generator installation?
The system size and the site drive the price. The main factors:
- Standby or portable. A standby unit costs far more than an inlet and transfer switch for a generator you already own.
- Generator size. Whole-house coverage takes a bigger unit than a handful of essential circuits.
- Transfer switch type. Automatic costs more than manual, and whole-house costs more than selected circuits.
- Fuel. Natural gas needs a line from the meter. Propane may mean a tank plus a line.
- Distance from the panel and gas meter to the pad.
- Site work, especially on sloped or rocky lots.
- Panel condition. An old or full panel may need work before a transfer switch can go in. See electrical panel upgrades.
- Permits and inspections for both the electrical and fuel sides.
Ask what's included: the generator, switch, pad, gas hookup, permits, and first service visit.
Should you repair your current setup or replace it?
If you have a standby unit that won't start or a transfer switch that won't switch, a service visit often solves it. Batteries, starters, and control boards are the usual suspects, especially on units that haven't been exercised regularly.
Replacement makes sense when the unit is too small for what you need now, parts are discontinued, or the original install skipped a proper transfer switch. If your current setup means plugging into a wall outlet, that's not something to repair. Replace it with an inlet and transfer switch before the next storm.
Frequently asked questions
Can I connect a portable generator to my house?
Yes, through an inlet box and a manual transfer switch or panel interlock installed by an electrician. Never plug a generator into a wall or dryer outlet. KUB warns that connecting to house wiring without disconnecting from the grid can send power back onto the lines.
What size generator do I need?
Size it to what you want running. The furnace blower, refrigerator, sump pump, a few lights, and outlets take a far smaller unit than central air, an electric range, and a water heater. Start with a list of must-haves.
How long does a standby generator install take?
The on-site work usually takes one to two days. Permits, the gas hookup, and generator delivery often add time, so plan before storm season, not during it.
Does a standby generator need maintenance?
Yes. Most run a short self-test each week, and they need periodic oil, filter, and battery service. A unit that's been ignored may not start when you need it.
What if the lights flicker after the power comes back?
Flickering or dead circuits after an outage can mean a loose connection or storm damage at the service entrance. That's an electrical repair job, and damage to the weatherhead or meter socket is the homeowner's to fix before KUB can safely restore full service.
Get an electrician out to your Knoxville home
Call to describe the problem or the project, or send the form. Someone will call back to set a time to look at it.