Backup Power

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Backup Power
Brownouts and blackouts cut your home's crucial electrical supply. Backup power systems keep the furnace warm, the refrigerator cool, and your home's security system online.

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In today's technology-driven world, backup power is fast becoming a household necessity. The same electricity supply that once ran only the basic necessities (lights, appliances, and heating and cooling systems) must now power computers, security systems, and smart-home automation. Increased uninterrupted power demands coupled with industry deregulation have made brownouts and complete power outages more prevalent in many parts of the country. While candlelight navigation may suffice for a few hours, when bad weather knocks the power out for days on end, a reliable, self-contained backup system can keep phones ringing, computers running, and heat pumping. And it is more than just convenience. When the heater is running pipes won't freeze, and when the security system is powered intruders are held at bay. Best of all, should the power fail modern systems power up automatically, whether you are at home asleep or across the country.

What's in a Watt
Backup power isn't a purchase that should wait until an outage is at hand. Planning is crucial, and begins with an assessment of your basic needs: refrigerators, lighting, computers, attic fans, heating, cooling, and security systems. Total essential wattage determines the size of your backup system (backup power systems are typically rated by the amount of wattage they can produce).

A permanent backup power solution, this natural-gas-powered generator from Kohler can support an entire home's electrical needs for several days.

Wattage calculations for backup power systems must accommodate the peak power load of all the devices to which they supply electricity. Accommodations are required for startup (which often uses more power), as well as the steady-run rate for all appliances. Furnaces are perfect examples of systems that demand high start-up power. A furnace with a slow-start motor option will help even out the load. Since more energy-efficient appliances directly impact how much load a backup power source can support, it's best to replace energy hogs if you expect to lose power on a frequent basis. A wood or gas stove is a good addition to backup power for homes with electric heat. A reputable dealer can help assess true wattage needs.

Sizing a System
It's more economical to buy a generator that's slightly larger than calculations of steady-run rates warrant, because a generator will need to handle all of the appliances coming online at one time. Since those startup loads are heavy, running the generator frequently at its maximum capacity will cause extra wear on the engine. Especially with manual startups, be certain to turn off all appliances first, then turn them back on individually once the generator is running. This will help avoid the strain that simultaneous startups can cause. If the system is automatic, everything will go back on at the same time, so the generator should be sized to accommodate the strain. Automatic shut-offs will kick in if the backup system is overloaded, which defeats the purpose of a generator.

Generators
Backup power comes from generators or battery systems. Generators make new energy, while chargeable batteries harness and store existing utility power for later use. First decide what must keep running and for how long. In the country, where restoring power may take days, a generator is the way to go.

Portable generators, like this model from Craftsman, can be used to power basic household appliances for short periods of time.

Gasoline, diesel, propane, and natural gas all provide fuel for household generators. Gasoline generators are available at home centers for a fraction of the cost of propane and natural gas units, but they have some drawbacks. Stored gasoline and diesel fuel are fire hazards and, over time, can become gummy or contaminated. Small gasoline generators are typically available for under $500, but installation and service are left to the homeowner. The time it takes to manually disconnect the power from the main circuit-breaker box and connect the gas or diesel generator to the auxiliary breaker panel also means that sensitive equipment like computers, security systems, and digital alarm clocks will require resetting. And, you'll also be left in the dark while the machine is shut off for refueling.

Propane and natural gas are more environmentally and economically sound fuels. Newer models come with an automatic switching device. It's wired alongside the household circuit box, and starts the generator in as little as 10 seconds after severe power dips or interruption. Refueling is not required, making for smooth, continuous operation. Propane or natural gas generators can cost anywhere from $5,000 to $10,000 depending on size. Figure on installation charges, as well.

Generator engines are cooled by water or air. Air-cooled systems are more cost effective. Liquid-cooled generators provide better temperature control and are quieter, an important feature in communities with noise restrictions. Perhaps the most important consideration is the reputation of the dealer who will install and service the unit. A licensed electrician and an experienced pipe fitter will ensure safe operation of the unit. In general, generators are located outside the home. It is important to have a voltage regulator and automatic shut-offs in the event of a problem.

Battery Backup Systems
In addition to serving as emergency backups, battery systems can also function as a cheaper daily alternative to electricity during peak daytime hours. Conservation-minded consumers can power essential needs using battery systems by day, and recharge the batteries during off-peak night hours.

Battery-powered systems, such as this unit from NextPower, provide a seamless transition to backup up power in the event of an outage.

Battery systems sometimes come in kits that include solar panels. These batteries are deep-cycle storage cells and come in banks or groups. A separate device called an inverter is necessary to convert battery power—which is direct current (DC)—to the alternating current (AC) that is used to power homes. A separate transfer switch is essential to activate the system. A small system capable of covering essential systems for a 12- to 24-hour blackout can run as little as $1,600.

NextPower, based in Illinois, has developed a self-contained battery backup system that is enhanced by digital electronics. The PowerBanc delivers instantaneous power within 16 to 32 milliseconds of a power loss, making it so seamless that even the most sensitive household systems won't detect a change. The advantages to this system over a generator include safe indoor installation and noiseless operation. The PowerBanc runs from $3,000 to $6,000, about a third less than the cost of a generator. The manufacturer recommends replacing batteries every seven to 10 years.

The disadvantage to any battery system is longevity, since batteries provide power only while charged. Even the most sophisticated system will last just several days—less if operating a full load. Depending on how critical uninterrupted power is, consumers may choose to purchase a small inexpensive generator that recharges backup batteries during an outage. Likewise, generator owners may find it necessary to purchase an uninterrupted power system (UPS) or small battery system to cover lapses during startup or refueling.

Text by Joyce Carroll
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