Fuel-Efficient Excavation

Last year saw diesel fuel prices reaching record highs, with prices spiking well above $3 a gal. in some parts of the country. And while fuel prices have eased over the past several weeks, global demand is almost guaranteed to push them back up as we approach the peak work season.

Given this scenario, cost control is even more crucial to ensure the continued profitability of your business. This includes making sure all of your equipment — including excavators — are operating at peak fuel efficiency.

Fortunately, manufacturers are making this easier via more fuel-efficient designs that deliver higher engine horsepower and improved hydraulic performance.

“Excavator manufacturers are continually trying to improve their machines to reduce operating costs and improve fuel efficiency,” says Mark Wall, product marketing manager - excavators, John Deere. A key focus has been getting maximum production out of the machine. “We always try to maximize cubic yards per hour. By moving more dirt per hour or helping to put more pipe in the ground in a day, we are improving the customer’s efficiency and lowering his cost of operation.”

More power, less fuel

“Individual owners have to look at all the manufacturers and pay particular attention to engineering,” advises Tony McGreavy, asset manager at D’Allessandro Corp., Avon, MA. D’Allessandro Corp. specializes in underground construction and site preparation. Its 22 excavators range from 10,000 to 100,000 lbs. and consist primarily of Komatsu units, plus Caterpillar, Deere and Volvo models. “Certain manufacturers are making big breakthroughs in fuel economy faster than others,” he adds.

Excavator technology is improving on an almost daily basis, says Dave Pooley at Hyundai. “With the introduction of Tier II EPA engine laws several years ago, engine manufacturers had to do some creative fuel design changes,” he explains. “The changes included electronic fuel delivery systems, which react much quicker in delivery, and governor control. The overall result is a more fuel-efficient engine that emits less pollution into the environment.”

“The EPA has led all manufacturers to really invest in R&D to meet the [emissions regulations],” agrees Peter Robson, hydraulic excavator product manager, Komatsu America. At the same time, his company had the goal to improve fuel economy even further. This led it to move away from mechanical fuel injection. “Now we have gone to the high-pressure common rail fuel injection system, which has fully electronically controlled injection timing.”

Advanced engine electronics have enabled manufacturers to introduce more fuel-saving features, such as the auto idle mode. “If an operator allows a machine to stand unused for a period of time, the engine will automatically go to low idle, and therefore use less fuel than if it were continuing to run at higher rpms,” says Lowell Stout, product manager for Terex excavators.

Changes in cooling system design are also contributing to better fuel economy. “These new systems use advanced technology in cooling core designs, along with high-performing fans that feature air foil blades,” says Wall. “These new fans use less energy than on prior models. This is energy that can be available to move dirt or to help improve fuel economy.”

These advancements combine to more economically deliver the same or more power. “They burn less fuel,” attests Calvin Thompson, a 30-year veteran equipment operator and owner of Thompson Grading, Dallas, GA. “For the rpms, you get more horsepower.”

This translates into greater productivity, while consuming less energy. “The biggest change I see in the excavators is the speed in which they dig,” says Thompson. “You have higher-output engines and you have higher-output hydraulic pumps. Time is so critical in this business. And it doesn’t take you as long to accomplish a project. ”

Improved modes of operation