Generating Interest

With the recent rotating outages that accompanied the frigid February winter storm still fresh in our minds, and with spring showers now expected, many United members have expressed interest in backup generation.  And though United operates with the full intention of delivering reliable electric delivery, Mother Nature often holds all the cards.

Backup generation can provide homeowners with extra assurance that they’ll have available power during emergencies when outages occur. Every generator has a maximum continuous power rating that must not be exceeded by equipment load. There are multiple types of backup generation options, including whole-home generators, portable generators and batteries, all having their respective pros and cons.

No matter which generation source consumers might choose, it is important to note that generators and all accompanying electrical equipment should be installed by a master electrician who follows NEC (National Electric Code) Standards.

The term “generator” often comes to mind for residential applications with a whole-home generator. Whole-home generators are installed on the exterior of a home and provide, as their name suggests, backup power for the entire home.

United can help determine the exact maximum power demand (in kW) that a home utilized in the past year, which will allow accurate generator sizing needed for a residence. These generators will include terminal connections for either a natural gas line or, more commonly in our territory, a propane tank. The external gas supplies allow the generator to become operational within seconds of a power outage.

The automation behind these types of generators is a device called an auto transfer switch. The  switch recognizes the loss of grid power and automatically calls on the generator to cycle. This transfer switch is a crucial component of any backup generation system because it disconnects electrical travel between the grid and the home. Without this, a generator could backfeed energy onto the grid, creating a dangerous situation for linemen trying to repair the outage.

These features, combined with their ability to power an entire home, has made them a popular choice for residential backup. However, these conveniences come at a steep price, and such a system requires annual maintenance. For example, a 22 kW Generac whole-home generator costs between $8,000 and $12,000 installed.

Annual maintenance should be performed by a certified technician for the brand of the generator chosen. This will ensure the generator is operating efficiently and will cycle on when needed most.

Another popular option for backup generation are portable generators. Portable generators generally have lower electrical outputs than whole-home generators, but they generally cost significantly less.

As their name suggests, portable generators can be transported between interconnection points, such as homes, camping sites and tailgate settings. The versatility of portable generators is an advantage that the other backup generation examples do not share. The simplicity of a portable generator allows consumers to plug in a variety of needed home equipment straight into the generator where it can be run in a well-ventilated, exterior location.

For easier use, a manual transfer switch and critical load sub panel can be installed and used in conjunction with a portable generator. For example, a generator will plug into an installed exterior wall 240-volt plug and supply power to your critical loads after a manual transfer switch has been operated.

These portable generators require refueling with either gasoline or diesel about every eight to 12 hours. Factors that influence runtime include size of the fuel tank as well as the percentage of total load being resourced by the generator.

Although these generators run at a lower wattage, most come with a price point under $1,000. With the addition of a critical load sub panel and manual transfer switch, the price increases to around $2,000 - $3,000 installed.

Lastly, batteries are another form of backup power. Batteries are the least popular option due to connection with a solar system, or another renewable energy source—the installation of which can contribute to an overall higher cost.

Generally, residential solar systems shut down when grid power is lost to prevent back feeding to the grid. When solar systems are combined with batteries, however, the solar system will remain on. During an outage, a home will draw power from the solar panels. If the panels are not producing enough or any power at all, the home will use battery backup until they are depleted. Overall, batteries are expensive to install, ranging from $10,000 to $15,000 each. This cost does not include solar installation.

Additionally, batteries will backup smaller loads only, such as dishwashers, refrigerators, fans and lighting. If the battery is supplying its maximum continuous power rating, it will only last a few hours. If the battery is supplying a smaller portion of power to the home, such as running some lighting and a couple of fans, it could last for approximately 10-15 hours.

Overall, if there is a primary concern for having sufficient power to run most or all electrical equipment in a home during an outage, generators outperform batteries in both usable power and installation costs.

Batteries, however, are a convenient addition to an existing or new solar system that is capable of providing  power during an outage.

Any of these options can offer members some peace of mind that some or all of a home’s critical loads will have power when it is needed most.

United’s Energy Expert team  is always on hand to provide more information on generators and batteries. They can also help members determine the right-size generator based on the residence’s  unique usage requirements.