Portable Power Moves Beyond Diesel

With so much focus on Tier 4 Interim and Tier 4 Final in recent months, it’s a welcome departure to see equipment suppliers looking at options beyond diesel engines. Leading the charge, so to speak, are generator and air compressor suppliers. Recent introductions by several manufacturers step outside the traditional diesel-powered box to deliver flexible, cost-effective alternatives for their customers.

Here’s a look at some recent offerings and their potential benefits. For more information on any of these products, visit the Buyers Guide at ForConstructionPros.com.

Multiple Power Supplies Offered

At CONEXPO-CON/AGG, Doosan Portable Power showcased several new power supply choices for its air compressors. In addition to a full line of Tier 4 Final-compliant diesel-powered models, the company launched gasoline- and electric-powered versions designed to address varying customer requirements.

“We understand that we have no one silver bullet that can meet all needs,” says Rus Warner, manager, global air products.

The new C185 gasoline-powered compressor is based on the company’s popular P185 diesel-powered unit. “The C185 is our rental-focused machine,” says Warner. “The gasoline engine offers another alternative in our portfolio for those who want another option for their fleet.”

Gas provides a less expensive option for both contractors and rental centers. “Rental rates aren’t rising fast enough to keep up with the rise in technology,” says Warner. “By offering a gas engine, you can get a [compressor at a] lower price point but still maintain the same rental rate. Gasoline is also becoming more and more accepted. You will see it in many other products.”

Rated at 185 cfm at 100 psi, the C185 is equipped with a 2.5-liter, fully electronic, fuel-injected Kubota gear-driven industrial engine built on a diesel block made gasoline-applicable for added durability and uptime. The unit also features an impact-resistant, corrosion-proof, tilting canopy and a cool-box design to keep internal package temperatures low to protect internal components.

Also on display was the new VP900e electric air compressor. According to Warner, the initial driver behind the VP900e was Tier 4 avoidance. “Customers realize Tier 4 models are more costly, more regulated and require more maintenance. They’re seeking an alternative solution,” he states.

The compressor utilizes three onboard electric motors controlled by a variable-frequency drive system consisting of one airend motor and two cooling fan motors, each sized specifically for their dedicated function. This design creates operational efficiencies.

“The VP900e operates between 400 and 900 cfm without wasted energy, due to intelligent engineering design,” says Warner. “We’ve designed the model in such a way that it automatically delivers the exact flow necessary for an application, conserving power and allowing for easier operation. ”

Variable frequency drive is at the core of the electric system. It monitors the needs of the compressor by changing performance of the motors to provide exact power requirements. During operation, it automatically adjusts to the load demand, maximizing flow for each pressure setting.

On the job, the operator has the capability to set the pressure at any level from 90 to 150 psi. “It allows control of the airend and cooling system for more flexibility and fuel efficiency,” says Warner. “The power is in the hands of the customer to customize the machine. They can adjust the settings to the application.”

A Gaseous Solution

Not to be outdone, Magnum Power Products presented a new line of gaseous-fueled mobile generators during CONEXPO-CON/AGG. Models range from 100 to 396 kW and can run directly on well gas in addition to natural gas and propane.

“The Magnum line of gaseous-fueled generators is purpose built to thrive in well gas applications with maximum uptime,” says Ben Froland, product manager for power generation. Each unit in the line features a heavy-duty spark-ignited engine designed to handle the impurities that come from running on raw natural gas.

Well gas is traditionally flared off in oil and gas applications. By running directly on this fuel source, the generators are reported to save users hundreds of dollars in fuel per day. To account for fluctuations in well gas, the units provide paralleling capabilities and automatic changeover so that power output is maintained. This allows a site to maintain power without customer interaction.

The generators’ engine management systems automatically adjust to run on propane, natural gas or well gas. The easy to use, full-featured controller can be programmed in the field for customized installations. A sound-attenuated enclosure ensures quiet operation.

Propane Powered Lineup

Kohler Power Systems debuted a new line of mobile generators at The Rental Show in February. The line is designed to offer customers more choice in terms of power output and customization.

The company announced plans to execute a staggered release of 15 models from February 2014 to June 2015. The line will include 11 Tier 4 Final-compliant diesel gensets ranging from 35 to 680 kVA, as well as four liquid-propane gensets ranging from 30 to 125 kVA.

According to Kohler, the propane-fueled gensets are capable of reducing users’ fuel costs by 15% to 20% when compared to diesel fuel. (Savings are based on $3.95/gal for diesel and $1.70/gal for LP, as published in December 2013 by the U.S. Energy Information Administration.) The propane models are also eligible for incentives of $1,000 to $8,500 from the Propane Education & Research Council (PERC).

“Developers, builders, and contractors can use propane technology to demonstrate their commitment to sustainability throughout the construction process and beyond,” says Bridget Kidd, PERC’s director of residential and commercial programs. “Simply by integrating propane-fueled equipment like Kohler’s new mobile generators into their daily operations, construction professionals can help ensure a cleaner environment without sacrificing power or performance.”

Representing the line at The Rental Show was the 125REZGT, a propane-fueled model with an onboard LP tank. Users working in areas without an LP gas supply can opt for the onboard tank, then switch to an on-site supply when working in areas with an LP gas connection. The onboard LP tank is built for a 24-hour runtime, while connection to an external LP or natural gas supply offers extended usage. Other optional add-ons include cam-locks and a voltage selector switch.

All of the new models include a patent-pending enclosure with straightforward access to all parts without disconnecting any wires or parts, as well as a fluid containment system.