Which kind of emergency backup generator is right for you? A range of permanent and portable generators are available, so here's how to choose. A power outage in the home can be a frightening event, especially if severe weather is right outside your door. However, there's another option to being left in the dark: an emergency generator. When the grid is down because of storms, hurricanes, freezing temperatures, or other natural disasters, it's never certain how long it will take to restore power to homes. In order to stay prepared, having a backup generator in place will provide your home with temporary power during an emergency.Permanent or portable?There are two types of generators: permanent standby and portable. Each carries benefits and drawbacks, so make an informed decision based on the geography of your home and how much power you'll need if the lights go out.Permanent standby generatorsThese remain permanently outside the home and on standby. They run on an existing fuel source—either liquid propane or natural gas—and are capable of generating enough wattage to re-energize your home only seconds after it loses power. That's because the permanent generator works in conjunction with a transfer switch to monitor incoming utility voltage. When your home's power goes out, the transfer switch will disconnect the utility line and connect a new power line from the generator to restore power within seconds.Due to the sheer amount of power that permanent standby generators are capable of providing, they carry a hefty price tag. However, the cost has come down during the past few years, making them more affordable. In addition, licensed electricians must install these generators, and your local utility company must be notified that you have a back-up system in place. However, if you live in an area that consistently sees power outages, this type of generator may be a good option and the best possible preparation money can buy. Also, if you live in a climate that is consistently very cold and plagued with ice storms, this generator may prove worthwhile to power your furnace and hot water heater, to keep your home warm and your pipes from freezing in the event of a prolonged power outage.Portable generatorsThese offer a more affordable option, when only a few vital electrical items are needed during a power outage. These generators are smaller and can be wheeled out of the garage. Their primary fuel is gasoline, so they should never be run inside the home or any enclosed area, where deadly carbon monoxide gas can accumulate.It is recommended that you install battery-operated carbon monoxide detectors indoors according to manufacturer's instructions. Take care when fueling a gasoline-powered portable generator; never add fuel while the unit is running or hot. If the tank is overfilled, fuel can overflow onto a hot engine and cause a fire or explosion. Always start or stop the generator only when no electrical loads are connected.Extension cords can be connected to portable generators and run inside to power smaller appliances like the refrigerator, sump pump, furnace, hot water heater, lamps, TVs, and computers.In order to select the best backup generator for yourself and your family, determine just how much power you would need in the event of a blackout. What could you do without for a few days? Hot water? Cold food? Check the manufacturer information for each appliance to find out the wattage of your necessary appliances, and then tally their numbers. A portable generator may be your best option if you stay aware of your energy consumption, and hold to using the wattage limit of the generator. Depending on the model, portables can generate between 2,500-4,500 watts. By using energy wisely, you'll still be able to comfortably endure a blackout.Remember, connecting a portable generator directly to your household wiring can be deadly to you and others. A generator that is directly connected to your home's wiring can "back feed" onto the power lines connected to your home and injure neighbors or utility workers. By working with a qualified electrician, you can install a manual transfer switch to safely tie into selected circuits of your main electrical panel. If a portable generator is running and power is restored, the power company's electricity cannot get to those isolated circuits until the generator is turned off and the manual transfer switch is reset to the non-backup position.Before you buyDetermine which electrical items are needed in an emergency.Remember: Homes in climates that have freezing temperatures need to protect against frozen pipes and the furnace will need to be on emergency power. Homes in climates that have hot temperatures and high humidity need to back up the air conditioner to protect against mold damage.To save the food in the freezer, the refrigerator will need to be on the system, as well as any stand-alone freezer.Homes with well-water will need to have the well pump on the generator system if toilets are to be flushed.Total the watts needed to determine what size generator is required. Consider both running and starting watts. An electrician can help make this determination, or you can check the manufacturer information for each appliance.Determine your budget.