The Georgia Ports Authority (GPA) has completed the assembly of 11 new rubber-tired gantry cranes (RTG), in conjunction with its capital improvement plans. The GPA estimates that these new cranes will conserve more than 83,000 gallons of diesel per year.

Besides typical generational changes, the newer models are more energy efficient. The cranes are designed with a power management system that operates at variable speeds. These RTGs are always ready to work, but only as dictated by demand. Operating within a spectrum from 800 to 2100 rpm, these machines burn an average of four gallons of diesel per-hour – a 33-percent fuel/cost savings compared with the existing fleet’s average consumption.

“Our responsibility to be good stewards of the environment is a top priority for the GPA,” said GPA Executive Director Doug J. Marchand. “As part of our environmental policy, the GPA looks at new capital improvement projects from the outset for ways to implement them in a more environmentally friendly manner. On several occasions, we have improved efficiency, increased cost savings and reduced negative environmental impacts – all in the same project.”

In July 2009, the GPA conducted a study to determine the fuel burn-rate of its RTGs. At the time, the fleet consisted of 60 machines utilizing one of three types of gensets, a diesel engine and alternator combination, which power the machines. These units operate at a constant engine speed of 1,800 rpm. On average, the older RTGs burn six gallons of fuel per hour.

In the next few weeks, the GPA will test two-speed upgrades on its older RTGs with the goal of achieving a more efficient level of energy use.

“Upgrades like these, not only improve our on-terminal operations but also decrease our environmental footprint,” said GPA Chief Operating Officer Curtis J. Foltz. “Refitting our fleet will enable us to take advantage of variable engine speeds and reduce fuel consumption - thereby decreasing per-hour energy use and emissions.”

The GPA’s entire fleet of container handling equipment is currently being retrofitted with engine exhaust enhancements to reduce air emissions as part of a U.S. Environmental Protection Agency Diesel Emissions Reduction Act grant.

“Further improving our environmental performance is good business and can improve the bottom line,” said GPA Board Chairman Steve Green. “The GPA is fully committed to reducing consumption and emissions, while maintaining our world-class operations.”