When general contractor Brasfield & Gorrie recently began construction on a new 60-bed rehabilitation hospital in Beachwood, Ohio, the construction firm had no access to temporary power on the site.
Rather than renting a diesel generator, the project senior superintendent Danny Parker turned to a growing alternative: a Kohler mobile generator fueled by propane. The primary reason? Cost. “First of all, after doing the research, I found out it is probably 30 percent more efficient than a diesel generator,” Parker says.
The prices of propane and diesel can fluctuate, of course, but construction firms frequently have access to lower-priced propane because of their large demands for fuel, says Mike Wilbur, owner and operator of Medina, Ohio–based Ohio Temp Heat, which provides rental equipment such as generators and temporary heat and air to commercial construction sites.
“Their bulk pricing for propane can be substantially cheaper than what they can go out and buy off-road diesel for,” Wilbur says. “When off-road diesel’s at $2 a gallon, and they can buy for $1.15 or $1.50 on the propane side and still get the same efficiencies, why wouldn’t you do that?”
For Parker, it wasn’t just a rhetorical question. He was able to make an apples-to-apples comparison because Brasfield & Gorrie is building a similar hospital for the same owner about 30 miles away. Parker’s counterpart used diesel generators on the other site. “I was able to compare numbers with them on a monthly basis to see where we stood cost-wise,” he says. The cost savings using propane? Thirty percent.
Clean and Convenient
Beyond cost savings, propane generators also come with a host of benefits on the jobsite, Parker says. One major convenience is a longer runtime thanks to the propane generators’ ability to run off an onboard tank or a larger external tank.
“It allowed me to set a 500-gallon tank out here instead of having a diesel truck out here two times a week,” Parker says. “With today’s technology, the propane company can remotely monitor the amount of gas in the tank. So when I get down to 30 percent or so, they automatically come out and fill the tank without me having to check it and take the time to make a phone call to schedule a delivery.”
The propane generators also offer a cleaner, quieter jobsite environment. “These generator packs are sitting pretty close to the [construction] office, so noise is a big concern, too,” Parker says. “You’re looking at 65 decibels vs. 80 decibels, which makes a big difference in a temporary office environment.” Plus, visitors won’t have to encounter diesel’s dirty emissions, Parker says. “Every time you fire the diesel generator, it blows soot into the air. If you’ve got visitors out here parked at your visitor’s complex, that soot inevitably settles onto vehicles.”
Propane’s clean emissions profile is also attractive on projects keeping an eye on their carbon footprint. “When it comes to schools, or any time public money is involved, there’s often the requirement to have a clean project,” Wilbur says. “It’s more of a bonus for these guys. When they find out there are propane-powered generators, it’s very easy for them to pull the trigger because it’s a win-win.”
More Power to You
The gas-fueled mobile generators were introduced by Kohler in 2014 in sizes ranging from 30 kVA to 125 kVA. In 2015, Kohler introduced a mobile paralleling box that allows users to combine different-size generators with different fuel types if they need a larger power capacity or an extra unit for backup.
“With today’s technology, the propane company can remotely monitor the amount of gas in the tank. So when I get down to 30 percent or so, they automatically come out and fill the tank.”
While general contractors are the primary users of mobile propane generators, Kohler has also found a niche with organizations and municipalities that employ a fleet of generators and move them around to back up multiple sites. “Even though they rarely use them, they like the propane tanks because the fuel will never go bad,” says Anne Feudner, product manager for Kohler Power Systems. “Whereas diesel will grow algae over time, and they have to clean that tank out every year.”
On the jobsite, the mobile generators pair particularly well with temporary construction heat, which, like the generators, is fueled by propane or natural gas. Using the same fuel for both heat and power provides additional convenience and bulk savings.
Parker, for instance, began using the propane generators after Wilbur’s company provided temporary heat on another healthcare project in Ohio. When the Beachwood project began, temporary power wasn’t going to be available for four months. So Parker used one generator to power the site’s two construction offices and then a second generator to supply power for the equipment needed to construct the building.
The rehab hospital is set for final turnover to the owners by mid-September — right on schedule, and with 30 percent lower fuel costs for jobsite power.