Best Home Generators: A Buyer's Guide to Types, Sizing, and Cost
Compare the best home generators by type, size, and cost, then call a licensed electrician for expert sizing and installation.
The best home generators aren't one specific model. They're whichever type, standby, dual-fuel portable, inverter, or battery and solar, matches your home's load, budget, and how hands-on you want to be during an outage. Sizing and connecting one is licensed electrical service work, the same category as a panel upgrade or a full rewire. This guide compares each category and breaks down sizing, cost, permits, and safety so you can decide with facts, not marketing copy.
Call a licensed local electrician now for a fast generator sizing quote.
Best Home Generators by Category
- Best for whole-house automatic backup: Standby generators on natural gas or propane, from brands such as Generac, Kohler, and Cummins, starting within seconds and running as long as fuel holds.
- Best value: Dual-fuel portable generators that switch between gasoline and propane, giving fuel flexibility without a standby unit's installed cost.
- Best inverter generator: Models that idle down under light loads, quieter than conventional portables with cleaner power for electronics.
- Best solar generator (no-gas alternative): Battery and solar-hybrid systems that recharge from panels or wall power with zero exhaust, at the cost of shorter runtime.
- Best portable generator for home use with no permanent install: A portable inverter in the 3,000-4,000 watt range, needing no transfer switch or permit with cords or an interlock.
Matching a Generator Type to Your Home
Every option still needs a home standby generator hookup, a manual interlock, or at minimum a portable generator safety setup.
| Type | Typical Output | Runtime | Noise | Install Needed | Best Fit |
|---|---|---|---|---|---|
| Standby (gas/propane) | 10,000-26,000+ W | Continuous, fuel permitting | Moderate, enclosure-muffled | Electrician, transfer switch, pad | Whole-house automatic backup |
| Dual-fuel portable | 3,000-10,000 W | 8-16 hrs per tank | Loud, 20+ ft from the house | Optional manual switch or interlock | Budget-conscious essential circuits |
| Inverter | 2,000-4,500 W | 8-20 hrs depending on load | Quietest fueled option | None, or a manual switch | Quiet operation, sensitive electronics |
| Battery/solar | 2,000-6,000 W | 4-12 hrs per charge, refillable via solar | Silent | Electrician (hardwire) or DIY (portable) | No-gas backup, mild climates |
What Size Generator Do You Actually Need
Add up the running watts of everything you'd run at once, then stack the single highest starting-watt figure on top since that's the surge the unit must survive, not every device's surge combined.
| Appliance | Running Watts | Starting Surge |
|---|---|---|
| Refrigerator | 600-800 W | 1,200-2,200 W |
| Central AC (3-ton) | 3,000-4,000 W | 4,500-6,000 W |
| Well pump (1/2 hp) | 1,000-2,000 W | 2,000-3,000 W |
| Sump pump | 800-1,500 W | 1,300-2,300 W |
| Furnace blower | 600-1,200 W | 1,200-2,400 W |
| Lights and outlets (whole house) | 400-600 W | negligible |
These are typical ranges, not nameplate figures. A whole-house generator installation quote should always include a real load calculation before you buy.
Fuel Type Trade-offs
- Natural gas: Piped in, rarely runs dry, though an outage that also hits gas infrastructure is rare but possible.
- Propane: Stored on-site in a tank you refill, dependable but you monitor the level and schedule refills.
- Gasoline: Cheapest to buy, but degrades within about a month without stabilizer and can get scarce during a regional disaster.
- Battery: No fuel logistics at all, recharges from solar or wall power, but has a hard runtime ceiling until charged again.
What a Home Generator Costs, Installed
Unit cost alone for a portable or inverter model runs a few hundred to around two thousand dollars, while standby units typically start in five figures before installation. Installed cost adds the pad, transfer switch, fuel hookup, permits, and inspection, often doubling a standby unit's sticker price, so weigh maintenance and fuel into the real 10-year cost. Some insurers discount a permanently installed standby unit, and certain battery-solar systems qualify for a clean-energy credit, so ask your agent and installer what applies locally.
Permits, Codes, HOA Rules, and Safety
Most jurisdictions require an electrical permit for a hardwired automatic transfer switch plus a mechanical or gas permit for the fuel line, ending in a final inspection. Local code sets clearance and setback rules for the enclosure, and towns and HOAs often add their own noise limits and placement rules, so confirm all three before you buy. Skipping a transfer switch risks backfeeding the grid, which can electrocute a utility worker and void your utility agreement. Portable and dual-fuel units must also run outdoors, at least 20 feet from doors, windows, and vents, since carbon monoxide has no smell and builds up fast in an attached garage.
Repair or Replace: When Your Current Unit Just Needs Service
If your existing generator is starting rough, tripping alarms, or losing output, generator repair is usually the cheaper move. Say your unit is a 10-year-old Generac standby model with a weak start battery, that's often a same-week fix, not a replacement. A licensed electrician who handles Generac generator repair can check the battery, the transfer switch, and the control board first. Wiring or panel issues found during that visit need licensed electrical repair before backup power gets added.
Frequently Asked Questions
What size generator do I need to run my whole house?
Add up the running watts you want covered at once, then add your largest appliance's starting watts on top, since that's the real surge the unit must handle. A licensed installer confirms the number with a load calculation first.
Standby vs. portable, which do I need?
A standby generator is wired to your panel and starts on its own within seconds of an outage. A portable generator needs fueling, hand starting, and cords or an interlock kit, costing less but asking more of you mid-outage.
Can a portable generator run central air conditioning?
Only if it's sized for the AC unit's starting watts, typically two to three times its running watts, so a small 2,000-3,000 watt inverter can't manage it. An 8,000-10,000 watt dual-fuel or standby unit is a more realistic match.
How often does a home generator need maintenance?
Standby units need an oil and filter check every 100-200 run hours or once a year, plus a battery check, since a dead battery is the top reason standby units fail during an outage. Portable units need fresh oil and stabilized fuel before long storage.
Bottom Line
There's no single best home generator for every house. A standby unit fits if you want the panel covered automatically. A dual-fuel portable or inverter covers the essentials at lower cost if you manage fueling and cords yourself. A battery or solar system fits homes that want zero fuel logistics and can live with a shorter runtime. Whichever you choose, get the load calculated and the installation permitted and inspected.
Call a licensed local electrician now for a fast quote on generator sizing and installation.
FAQ & Troubleshooting Nodes
Q:What size generator do I need to run my whole house?
Add up the running watts of everything you want powered at once (fridge, well pump, furnace blower, a few circuits of lights and outlets), then add the single largest appliance's starting watts on top since that's the real surge the unit has to handle. Most licensed installers confirm the final number with a load calculation before recommending a size.
Q:What's the difference between a portable and a standby generator?
A standby generator is permanently wired to your panel through a transfer switch and starts on its own within seconds of an outage. A portable generator has to be rolled out, fueled, started by hand, and connected through cords or a manual interlock kit.
Q:Can a portable generator run central air conditioning?
Only if it's sized for the AC unit's starting watts, which typically run two to three times the running watts, so a small 2,000-3,000 watt inverter usually can't do it. A dual-fuel or standby unit in the 8,000-10,000 watt range or higher is a more realistic match.
Q:How often does a home generator need maintenance?
Standby units typically need an oil change and filter check every 100-200 run hours or once a year, whichever comes first, plus a battery check since a dead start battery is the most common reason a standby unit fails during an outage. Portable units need fresh oil and fuel stabilizer before any long storage stretch.