Portable Generators for Emergency Power

The most economical way to supply power during a power outage is to use a portable generator of the appropriate wattage for your needs (at least 4000 Watts for starters) and run extension cords into the house to power chosen appliances. A safer system is to have an electrician install a power transfer switch, connected to the house's main electrical panel. Just fire up the generator, run a single extension cord into the transfer switch and power the circuits you need through the main circuit breaker. This eliminates the risk of electrical “back feed” injuring utility workers repairing downed power lines.

A small portable gasoline-powered electric generator can provide power for TVs, small kitchen appliances, hair dryers, power tools, lights and other comforts of civilization when you are out roughing it in the woods.

Portable generators can be put to work on construction sites that have no electrical service, providing clean, reliable power to operate saws, drills, air compressors, heaters, paint sprayers and other AC-powered tools. Most are gasoline-powered, a few run on diesel, and some models have multi-fuel capabilities, running on gasoline, propane or natural gas. These are generally full-featured machines with engine idle control, GFCI receptacles and 120 Volt full power switch.

Residential Standby Systems

An emergency home standby generator system can automatically restore power to your house in about 20 seconds. When the power goes out, the generator automatically starts and continues to run until power is restored. You can choose a generator that delivers enough power for the entire house (including air conditioning) or go with a smaller unit and power a few selected circuits, like the refrigerator, sump pump, furnace fan and several lights for basic survival.

These all-weather generators are installed outside the home and are wired through an automatic transfer switch (sold separately) to the main electrical panel. The use of an automatic transfer switch is required when generators are connected to home wiring.

Home standby systems can be fueled by natural gas, LP gas or diesel fuel. Many models can be connected to the home's natural gas line, eliminating the need to fill fuel tanks. Standby system capacities range from 6,000 Watts up to 40,000 Watts and more, and start automatically-even if you are not home.

Commercial Standby Systems

If you have a business that simply can't be without power or you have no existing source of electrical power for your home or business, you will need an industrial generator. These are typically stationary, heavy-duty units that generate single (120 Volt) or three-phase (120, 240 or 480 Volt) power. These larger systems are powered by water-cooled diesel engines, with some models generating up to 200 KW (200,000 Watts) of power. With the use of an automatic transfer switch, these generators can serve as backup power for large commercial or industrial operations, such as nursing homes, refrigeration operations, farms, large buildings and other businesses that can't go without power due to an outage.

Questions You Should Ask Before You Buy a Generator:

• What is the generator's wattage capacity and will is support your needs, including startup surge power required by some equipment?
• Does the generator have enough outlets to plug in all of the items you want to power?
• How noisy is the generator?  Are there noise restrictions in your neighborhood?
• What type of fuel does the generator use?
• How large is the fuel tank and how many hours of operation will it provide?
• Is the generator easy to move around?  Does it have built-in wheels and handles for portability?
• What accessories will I need to run the generator (fuel, heavy-duty extension cords, transfer switch)?

How Many Watts Will Your Generator Need to Produce?

Add up the wattage of tools, appliances and motors you want to run at the same time. Then select a generator with the RUNNING wattage rating to match or exceed the total load. Keep in mind that tools and appliances with electric motors require additional tool/appliance SURGE wattage at startup that can be double or triple the normal running wattage requirement. Look at the surge watts required and make sure you choose a generator with enough additional wattage to start them. Keep in mind that you typically are not starting more than half of the items at the same time.

Most home appliances and power tools are 120 Volts; larger appliances like electric stoves and clothes dryers may be 240 Volts.  Generator power is measured in Watts: Amps x Volts = Watts.

See Wattage Chart for additional assistance in calculating your needs.