PRODUCT TRENDS: Generating Power

Generators supply power on job sites where electricity is needed, but not readily available. But a generator is a piece of equipment many contractors may not know much about. Adding to the confusion is the multitude of choices available. Generators come in a range of wattages. Some are noisier than others. Some are more portable, and some are more durable. With all the variations, contractors can be left wondering how to select the right one for their needs.

THE RIGHT CHOICE. The first question a contractor should ask is obvious enough: What is the generator’s primary purpose? Contractors must first figure out what type of equipment and, if applicable, how many pieces of equipment will be running off of the generator at one time.

The next step is to find out how much power the equipment needs to run. For example, if a contractor is going to run three pieces of equipment, he has to know how much power each piece requires, says Dale Gabrielse, training manager, Robin Subaru, Wood Dale, Ill. “And if he wants to run all three at the same time, he has to add that up and choose a generator big enough to handle that,” he says.

But how do you figure out how much power the equipment needs to run? Most equipment will have a data tag or plate with a rating on it that tells how many amps the electric motor draws and how many volts it runs on, says Rick Kier, president of Syracuse, N.Y.-based Pro Scapes. Multiplying the amperage by the voltage will give the wattage, he says. “For example, a circular saw drawing 10 amps on 120 volts would need 1,200 watts to run,” Kier says.

It’s also critical to keep start-up amperage in mind. “When you’re running power tools off of a generator, start-up amperage is important because electric motors always take more to get started,” Kier says.

If the generator a contractor is using is too small, it won’t have enough wattage to start the equipment. But fortunately, most equipment is rated on its start-up amperage, so the data tag information already takes that into account.

In addition, many generator manufacturers can provide average wattage requirements for various pieces of equipment, with some even offering charts online. But remember these are averages, so it’s important to use them only as a guideline, says Gabrielse.

Once the necessary wattage has been calculated, contractors should then select a generator that is larger, rather than smaller, than their needs. “You add up everything you want to run,” Gabrielse says. “Then you add on another 300 to 400 watts as a cushion.”

Kier agrees it’s important to leave some wiggle room when it comes to wattage. “You have to think about what equipment you want to run and what its draw is and give yourself room in case you want to run two of that equipment off it in the future,” he says. “You don’t want to buy the bare minimum.”

COST CALCULATIONS. Contractors also need to consider how much they want to pay for a generator. Gabrielse notes the wide range of prices and types of generators available. “You can go to Home Depot or Lowe’s and you can buy a 6,000-watt generator for $500 to $600,” he says. “But higher quality generators cost double, sometimes 2.5 times, that price. A high-end 6,000-watt generator may be $1,300 instead of $500 to $600. But you’re buying a better quality generator.”

Kier also agrees that the cost of generators varies greatly. “Depending on the bells and whistles you get, generators can cost $200 to $4,000 – sometimes even more,” he says.

But with a higher price tag comes better quality, says Gabrielse. Better quality means quieter, more durable, lighter weight and longer life equipment, he says. If these factors are important to the contractor, the generator is worth the money. If the generator will be used on a regular basis or in areas where quiet operation is a necessity, a higher quality generator is the best option, he says.

Kier puts his two portable generators to work mainly when planting flowers on large commercial sites, such as shopping centers. “We plant 30,000 annuals in the spring and we set it up like a mass production line,” he explains, adding that one crewmember has the potted plant while another uses an auger to dig the hole, and another crewmember follows behind to do the actual planting. “The generator is mounted on flower carts and we move them around the site.”

One way to try out a generator without a large investment is by renting one. Kier owned a 4,000-watt generator for 15 years. “It came with a motor home we bought to use as a job site office,” he says.

At first, Kier would use that generator and then rent another one during planting season. “But we would incur extra costs when we rented the second one,” he says, so about a year ago he purchased another 2,500-watt generator. Kier estimates that he runs his portable generators around 100 hours a year.

When it comes to generators, Kier also stresses the importance of ground fault interrupters or GFIs. “Generators need a GFI because without one, you can be electrocuted,” he says. “In my opinion, every generator being used in professional business should have a GFI.”

Fortunately, most generators today have the GFI built right in. Older ones, Kier says even as recently as 8 to 10 years ago, don’t usually have one. “You can buy one for around $50 and attach it to your generator,” he says. “We require our employees to use a GFI on our older generator.”

MAINTENANCE TIPS. Once the selection has been made and the perfect generator purchased, it’s important for contractors to keep the generators running as long as possible. The maintenance is fairly easy, requiring the oil and air filter be changed regularly. “The hardest thing on generators is that people don’t use them,” Gabrielse says, adding that moisture builds up when generators aren’t used. “If they're not being run regularly, generators need to be exercised every so often to burn off any moisture. They are electrical pieces of equipment.”

Gabrielse recommends contractors run portable generators once every six months for at least an hour. “Ideally, it would be nice to run it 20 to 30 minutes on a quarterly basis,” he says.