Inverter generator vs. conventional generator: which is better for an outage?
Short answer
Choose an inverter generator if you mainly need to run a fridge, electronics and a few essentials quietly. Choose a conventional generator if you need a lot of watts on a budget, for example to run a well pump, furnace and fridge together through a transfer switch. Inverter models produce cleaner power, run quieter and save fuel at light loads; conventional models cost less per watt.
How they differ
A conventional generator runs its engine at a fixed speed to produce 60 Hz AC power directly. An inverter generator produces power, converts it to DC, then electronically turns it back into clean AC. That extra step lets the engine speed up and slow down with the load.
Side-by-side
| Feature | Inverter generator | Conventional generator |
|---|---|---|
| Power quality | Clean, safe for sensitive electronics | Rougher; fine for motors and heaters, less ideal for electronics |
| Noise | Noticeably quieter, especially at light loads | Louder; runs at full speed all the time |
| Fuel use | Lower at light loads (eco mode) | Similar whether the load is light or heavy |
| Typical size range | About 1,800 to 5,000 running watts | About 3,500 to 12,000 running watts |
| Price per watt | Higher | Lower |
| Weight and portability | Lighter, compact | Heavier, often on a wheeled frame |
Which one fits your outage plan?
- Fridge, freezer, lights, Wi-Fi, CPAP, phones: a 2,200 to 3,500 W inverter generator is usually enough and much easier to live with.
- Add a sump pump, furnace blower or window AC: look at larger inverter models or a 4,000 to 5,500 W conventional generator.
- Well pump and several large loads through a transfer switch: a 7,500 to 9,500 W conventional generator gives the most watts for the money.
Get your actual numbers from the generator size calculator before you shop.
Noise matters more than people expect
During an outage you may run a generator for many hours, often near your own windows and your neighbors'. Some neighborhoods and campgrounds have noise rules. Inverter generators are much more pleasant to live with for days at a time.
Generator safety
Carbon monoxide from portable generators kills people every year. The U.S. Consumer Product Safety Commission advises running any portable generator outdoors only, at least 20 feet from the house, with the exhaust pointed away from doors, windows and vents. Never run one in a garage, basement or shed, even with the door open. Look for models with an automatic CO shut-off, and install battery-powered CO alarms inside.
Frequently asked questions
Is an inverter generator safe for computers and TVs?
Yes. Inverter generators produce clean power similar to the grid, which is safe for computers, TVs and other sensitive electronics.
Are inverter generators more fuel-efficient?
At light loads, yes. Their engines slow down when demand is low. At full load, fuel use is similar to a conventional generator of the same size.
Can I connect two inverter generators together?
Many inverter models can be paired with a parallel kit to roughly double the output. Both units usually need to be the same brand and compatible models.
Sources and method
Runtime figures assume 85% of battery capacity reaches AC appliances and typical US appliance ratings. See exactly how we calculate. Found a mistake? Tell us and we will fix it.