Generators are sold by power output, measured in watts. The amount of power they deliver determines how many lights and appliances you can operate at once; the quality and consistency of that power determines how well they'll run. You can make a list of what you plan to use, then add up their watts to get you in the right ballpark. Here are some rough numbers:
- Refrigerator: 600 watts
- Sump pump: 750 to 1,500 watts
- Portable heater: 1,500 watts
- Window air conditioner: 1,000 watts
- Lights: 60 to 600 watts
- Computers: 60 to 300 watts
Portable and inverter generators can both be moved around, though they come in different sizes.
- They typically run on gasoline that you may need to store in large quantities. Stabilizer must be added to your fuel for prolonged storage.
- You can use portable generators anywhere on or off your property—but never in an enclosed space. These models can quickly produce deadly levels of carbon monoxide. Always run a portable generator at least 20 feet away from your home, including equipment such as a central AC condenser or window AC, and direct the exhaust away from your home or any other structure, including the neighbors' home.
- Several models offer electric starting. The battery required, however, may not be included.
- Because their engines are more complex, these models generally cost more than portable generators of a comparable output.
- Inverter generators are much quieter than their conventional counterparts because they throttle up and down to match demand rather than run at full power all the time. They also have more sophisticated exhaust systems which also help tamp down noise.
- They run more efficiently and produce fewer emissions, but you should still follow all the same safety precautions you would with a portable generator.
Additional Features to Consider
- Automatic Start - When the power goes off, the generator goes on—without you lifting a finger.
- Electric Start - Several portable models offer this push-button alternative to the hassle of pull-starting the engine. Alternative Fuel Capacity
- Most portable models run only on gasoline, though some come equipped to run on a propane tank or natural-gas line and others can be converted with kits.
- Multiple Outlets - Four or more lets you best use the wattage by spreading the load, though we recommend using these only in an extreme pinch at home, or for when you're away at a campsite