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Properly Sizing a Portable Generator for your Needs

Properly sizing a portable generator for your home is essential. According to The Consumer Products Safety Commission in MachineDesign.com (May 7, 2009), 10.6 million U.S. houses had portable generators in 2005 and that number keeps growing every year. Generators usually generate between 5 to 6 KW of electricity and are gasoline-powered. Portable generators have been used after hurricanes, ice storms, thunder storms, floods, tornados and other emergencies. In those weather situations, power outages can be out for an unknown amount of time so an energy alternative is necessary. Homes in Florida, the Gulf coast, and coastal Northeast, and other areas where severe weather exists are candidates for portable generators. Following is an explanation of properly sizing a portable generator.

Properly Sizing a Portable Generator
Most portable generator models fall between $1,000 and $3,000. The deciding factor for properly sizing a portable generator is determined by wattage of items you need to power. Total appliance wattages you will be running to give you the portable generator size you will need. Three categories of portable generators: small, medium, and large. To give you an idea of what a small portable generator of about 3,000 to 4,000 watts will run is the following: a TV, refrigerator, 3 or 4 lights, and microwave. A medium-sized portable generator, 4,500 to 7,000 watts will run a computer, 7 to 8 lights, portable heater, TV, refrigerator, and microwave. Portable generator of 10,000 watts will power an additional hot water heater, a few more lights, central air conditioning or electric range (4,500 watts), computer, portable heater, TV, refrigerator, and microwave. Keep in mind surge wattage when some appliances first come on in calculating the proper wattage size.

Why Properly Sizing a Portable Generator is Important?
Losing power can leave you without heat, air-conditioning, potable water, sanitation needs, and other life-threatening necessities as medical equipment. Quality of life can degenerate quickly without electricity. A new candidate for portable generators is homes that need to keep computers running for a home business. Generally, portable generators keep regular lifestyle somewhat uninterrupted in times of emergencies.

Additional Tips for Properly Sizing a Portable Generator
• Safely run your portable generator at least 15 feet away from your house in the open air to prevent carbon monoxide poisoning
• Refuel only after generator has cooled and is turned off
• Use gas-ethanol blends of 15% or less ethanol

In conclusion, this article covered how to properly size a portable generator, what it means have a properly sized generator, and why properly sizing a portable generator is important. Listed below are some usual wattages of some of the devices found in a typical household.

Device
Typical Wattage
Surge Wattage
Light bulb 60 watts 60 watts surge
Fan 75 watts 150 watts surge
Small black/white television 100 watts 150 watts surge
Color television 300 watts 400 watts surge
Home computer and monitor 400 watts 600 watts surge
Electric blanket 400 watts 400 watts surge
Microwave oven 750 watts 1,000 watts surge
Furnace fan 750 watts 1,500 watts surge
Refrigerator 1,200 watts 2,400 watts surge
Well pump 2,400 watts 3,600 watts surge
Electric water heater 3,500 watts 3,500 watts surge