Perishable food in a refrigerator can be considered safe for about eight hours in a power outage. That time period becomes considerably shorter, however, if the door is opened repeatedly. But should your customers need to worry about opening their refrigerator door in a power outage?

That scenario is just one reason builders and remodelers should consider offering a standby power supply to their homes, according to Tom Jaenicke, an energy advisor for the Propane Education & Research Council and instructor at the International Builders Show seminar “Specifying Standby Generators as an Option for Remodeling Projects.” Power outages during construction can be expensive and frustrating, he noted. They can also create serious problems after a home is completed: frozen pipes, flooded basements, and mold issues, for instance, not to mention security and phone systems that rely on a power supply to operate.

Builders and remodelers can provide assurance against these hazards by offering standby generators as an option on their projects. And those systems have never been more affordable, said Scott McCaskey, director of new business development at Generac, who provided product expertise at the seminar. An entry-level unit costs about $1,000, he said, so pros can offer an installed system for less than $1,800.

Builders and remodelers can help their customers specify the right-size standby generator by discussing what systems the owner would like to back up in the event of an outage.

Cost is just one concern for building pros to consider when specifying a standby generator. They must also choose between three types of generators – portable, standby, and off-grid – with variables including wattage output, cooling method, and fuel type. At the session, Jaenicke highlighted several factors for builders and remodelers to consider as they make their decision. (To start searching for a standby generator for your next project, browse our propane products directory.)

Generator Type

Portable, standby, and off-grid generators each have applications in different types of residences. Portable generators typically cost the least but come with a number of drawbacks, Jaenicke said. For instance, they must be fueled and started by hand before they supply electricity. Most portable generators are fueled by gasoline, so owners must scramble to fill or find their gas can and make sure the gas hasn’t degraded, often running to the gas station only to face long lines or even closed stations in the worst storms. (On the other hand, propane-fueled portable generators, such as Generac’s LP5500 on display at IBS, rely on clean, stable, and convenient propane tanks, so they can be an ideal source of power for construction sites.)

Standby generators are safely and permanently installed outside the home, Jaenicke said. They are available with an automatic transfer switch that activates the generator in an outage, meaning owners have to change little of their daily routines. And they operate much more quietly than portable generators. An owner can converse normally while standing next to an active standby generator, McCaskey noted. “A standby generator should work within the community that you live in. It shouldn’t upset neighbors while it’s running, like a portable would.”

Often used in applications such as hunting camps or ski lodges, off-grid generators work well for homes and facilities operating independently from the main electric grid. Some of these units can be combined with renewable-energy sources, such as solar panels or wind, and a battery bank. In those cases, the generator will only activate to recharge the battery bank when it becomes depleted.

Power Output

The power output needed for a standby generator is dictated by the size of the home, the number and type of circuits connected to the generator, and how the owner plans to use the backup power, Jaenicke said. The generator can provide whole-house backup or power for only certain key appliances such as air-conditioning, heating, water heating, and wells.

Generac offers some standby generators with load-shedding circuits, said Bob Cramer, the company’s technical support manager, who offered technical assistance at the seminar. If a standby generator becomes overloaded, a load-shedding system can disconnect a device such as a water heater or stove to bring the demand down. This technology allows customers to purchase a smaller generator than they would otherwise need to provide whole-house backup.

The manufacturer also offers an onsite sizing tool for its dealers, Cramer said. “They come in the house, sit down with the customer, and walk through the house and let them know what they can back up. It will automatically size the generator for them right on the spot.”

Fuel Source

A propane or natural gas-fueled standby generator is the best option for a home during a power outage, Jaenicke said. Propane does not degrade like gasoline. It can sit in the tank for years and still be as effective as the day the tank was filled. Propane does not oxidize, and it won’t varnish or gum the fuel system of the generator engine. And it is a clean fuel that reduces emissions when compared with gasoline, diesel, or E85 (ethanol) gasoline.

Propane may also deliver additional advantages over natural gas, Jaenicke noted. In some cases, a standby generator may be the first gas entry point in the home, so propane may be a more affordable fuel option when you calculate the infrastructure cost to bring natural gas to a home. And some owners choose to use a propane standby generator even when natural gas is available, Jaenicke said.

“In situations like Hurricane Sandy or the hurricanes in New Orleans, natural gas can be shut off for literally months,” he said. “A propane standby generator starts to makes sense when you realize you have your own propane supply on site and a relationship with a propane retailer that can keep it full for you.”

Seminar attendee Troy Asleson, a custom builder and owner of Apple Valley, Minn.-based Stone Cottage Construction, said his firm has seen more interest from customers in standby generators after recent storm outages across the country. “It’s more of the uninterruptible power source,” he said. “If there’s a storm, your natural gas or your propane supply is there.”

Asleson added that he was surprised to find out how quiet standby generators could be. “I assumed they were going to be loud things,” he said. “The difference between 60 decibels [the noise level of a standby generator] and 70 decibels [the noise level of a portable generator] is monumental, and I didn’t realize that.”