With no lights, no heat, and no appliances, homeowners in a blackout are plunged into the Dark Ages. Power outages can cause frozen pipes, mold growth, spoiled food, and loss of heat or running water. So in storm zones, where vicious weather knocks out power with grim regularity, the comfort of a standby power system is worth the price. Permanent backup generators are increasingly common in coastal states from the Carolinas to Florida and in New England where powerful storms and shared power grids can threaten local power throughout the year.
Deciding on a Permanent Generator
Portable generators can replace part of a household load during an electrical outage, but these devices are typically loud, hard to move, run on gasoline, and limit the number of appliances that can run at any one time. A permanent backup power system can run off the home’s propane or natural gas supply and can be directly wired into the household circuit panel. These systems provide a seamless switch from utility service to backup power.
Some companies market fully integrated systems that feature switching devices and distribution panels in addition to the generator itself. Kohler’s Residential Standby Generator systems have a transfer switch “brain” that monitors the home’s utility power for interruption. If one is detected, the switch automatically fires up the generator and transfers the electrical loads, bringing power back to the house. The same process, in reverse, brings normal utility power back on line when service resumes. “Our generators can have power brought to the home within 7-10 seconds of an outage,” says Stephanie Dlugopolski, Senior Communications Specialist with Kohler. This is huge reassurance for homeowners who might not be home at the time of an outage, but still want their home and property protected.
Permanent generators can be set up to power the whole house during an outage or just the essential loads like the furnace, security systems, and various appliances. Whole house distribution naturally requires a more powerful generator, and a transfer switch that carries the same rating as the home’s main distribution panel. Transfer switches, which are essentially special electrical panels, come in automatic and manual models. Automatic systems are more expensive, but they provide ongoing protection and reassurance for homeowners. A manual transfer switch is less expensive and requires the homeowner to power up the generator and manually switch the load to the backup system.
Permanent generators are preferred in neighborhoods with noise restrictions because they are housed in sound deadening material to minimize sound output. “We make constant improvements to our models and the housing to reduce noise,” says Dlugopolski.
Determining Generator Size
Permanent generators are rated by their maximum electric output, measured in kilowatts. Generators with higher the wattage ratings cost more, but can power more appliances when the electrical grid goes down. Determining what size generator is appropriate for the home’s backup power supply comes down to listing the appliances and items that will be run during a power outage and totaling the required wattage. It is important to account for an appliance’s start-up or surge requirements, which is higher than normal running wattage needs. A local generator dealer/installer or electrician can help determine a home’s electrical load and recommend the appropriate size for a backup power system.
Common household appliances range from a light bulb that requires 50 watts to run, to a water heater that can require as much as 4000 watts. A refrigerator needs 1200 watts, but it consumes 3000 watts at startup. When adding up the appliance list, use an appliance’s start-up wattage. It will be listed in the appliance manual or on the appliance itself.
Installation of a permanent generator is a job for the experts. Not only must the wiring to the transfer switch and circuit board be done according to local code, a plumber may be needed to set up the hoses to connect the generator to the home’s fuel supply. Licensed generator dealers commonly oversee the installation process, and some will secure the permit and schedule the electrical inspection as part of a package deal. Clark Public Utilities of Vancouver, Washington, sells one-stop generator packages that include an Onan generator, the necessary permit, and installation of the system. Their price for a 12 kW generator package, excluding the cost of the transfer switch, is $4,367. A 20 kW system is $8,344. Purchase of a Kohler system also includes the transfer switch and installation costs. “A homeowner can expect to pay between $5000-7500 for an 8-12 kW package,” says Dlugopolski. “We encourage consumers to purchase through a dealer or have an electrical contractor install it because these are not do-it-yourself jobs.”
A permanent generator is installed outside the home, usually on a concrete pad and near the utility meter. Kohler’s 8.5 kW and 12 kW generators come with a built-in mounting pad, eliminating the need for the concrete pad. If the generator is to run off the home’s fuel supply, a hose is attached to the generator and run into the house to connect with the propane or natural gas. Wiring is run from the generator to the transfer switch, which is commonly installed inside, next to the distribution panel. The transfer switch is connected to the home’s main distribution panel and monitors the power supply for interruption.
Credit: Renovate Your World