The Georgia Ports Authority (GPA) of the US recently unveiled its first four electrified rubber-tyred gantry cranes (ERTG), the technology for which was developed with the help of partners Konecranes, Conductix-Wampfler and Georgia Power, which provided the cranes, the new power system and the electrical infrastructure, respectively.

GPA is the first organisation in North America to introduce this type of cleaner and more efficient method of operation. The new technology reduces fuel consumption by an estimated 95 per cent.

“This transition to electrified RTGs is an important milestone for the GPA and our industry,” said GPA executive director Curtis Foltz. “This project is the latest in a series of GPA initiatives designed to increase the productivity and capacity of the port in environmentally responsible ways.”

Through efforts such as electrifying ship-to-shore cranes and refrigerated container racks, the Port of Savannah avoids the use of more than 5.4 million gallons of diesel annually. The new cranes will further reduce the GPA’s fuel demand.

“Georgia Power’s partnership with the Georgia Ports Authority provides a great opportunity to further research and develop non-road electric transportation while adding value to the port’s day-to-day business,” said Murry Weaver, Georgia Power’s vice president of sales. “The ERTG system will not only offer significant cost savings and environmental benefits, but it will also position the GPA as a leading model for ports throughout the nation.”

While relying on cleaner, shore-based power to handle containers, the ERTGs feature the ability to automatically switch to diesel generators when moving from stack to stack. All functions are controlled by the ERTG crane operator.

Foltz said long-term plans call for retrofitting the Garden City Terminal’s fleet of diesel-powered RTGs to use shore power via retractable arms which will link to a conductor rail system, bringing the total number of ERTGs to 169 by 2022. Repowering the RTGs will be a multi-year initiative, requiring new cranes to be ordered with electric power capabilities, and some older cranes to be retrofitted. When complete, the ERTG fleet will allow the GPA to avoid the use of 5.97 million gallons of diesel each year. This will result in a net savings of nearly $10 million each year, even after the purchase of electricity is factored in.

“We are very proud the GPA has chosen Konecranes again as its reliable partner with the latest technologies for RTG cranes,” said Tuomas Saastamoinen, director of sales and marketing for port cranes. He said the four Konecranes ERTGs delivered earlier were operating very well and said the company was working with the Georgia Ports Authority as it continues its transition to cleaner, quieter electrified RTGs.

GPA director of engineering Chris Novack said ERTGs are more reliable than diesel-powered versions with less downtime. In addition, fewer hours of diesel-powered operation will mean reduced maintenance costs and extended diesel life.

Conductix-Wampfler installed the required power infrastructure. The ERTGs will switch via an auto-engage system between diesel and the electrical grid. About 90 per cent of the time, the cranes will operate on electrical power.

The RTG-mounted electrical equipment and retractable arm are compact and lightweight – important factors for subsequent ports considering a transition to electric power.

“This means it can be used for any ERTG, even those with little room for additional components,” said Jerry Koetting, district sales manager at Conductix-Wampfler. “We therefore assume that the product can set entirely new benchmarks in the ERTG electrification market.”

Custom-built to a GPA design, the ERTGs are powered through 480-volt conductor rails installed on the container yard at the rear of Container Berths 4 and 5. They will capture power when lowering boxes – energy which is currently lost under diesel power. For comparison, the GPA’s electrified ship-to-shore cranes reduce their power demand by about 35 per cent by capturing energy from lowering boxes.

Future reliance on ERTGs will drastically reduce diesel consumption at GPA, aiding the authority’s ongoing commitment to environmentally responsible operations.

GPA board chairman Robert Jepson remarked: “Our staff and technical partners have developed a cutting-edge tool that will help not only the GPA, but other ports around the nation to revolutionise container handling. Our ERTG design sets the pace for the industry, by dramatically reducing the fuel consumption, diesel emissions and noise normally associated with older technology.”