THE Georgia Ports Authority (GPA) has agreed to spend US$170 million on 55 hybrid-engine rubber-tyred gantry cranes (RTGs) for the Port of Savannah's Ocean Terminal.

The purchase comes as part of a greater effort in redeveloping the terminal into an all-container facility, according to the GPA.

The new cranes reduce emissions by half compared to conventional diesel cranes, reports London's Port Technology.

At an annual average of 4,000 operating hours per RTG, the hybrid engines will avoid yearly emissions of 127 tonnes per crane, or nearly 7,000 tonnes across the 55-RTG fleet. The new cranes can also work stacks that are six containers high and seven wide - one container wider than GPA's current largest RTGs.

The hybrid machines will exclusively operate off electric battery power, with diesel generators running only to recharge batteries.

This will reduce fuel consumption by an estimated 47 per cent compared to all-diesel machines, according to the GPA. Annually, that is a reduction of 8,800 gallons of diesel per crane, or nearly 500,000 gallons annually across the Ocean Terminal fleet.

This will result in a fuel purchase savings of more than $1.6 million per year at current rates.

"This significant investment in new equipment will help prepare the Port of Savannah to handle more ships and cargo," said GPA executive director Griff Lynch.

"These new machines will expand our capabilities, operate at lower cost and leave a smaller carbon footprint than conventional diesel cranes."

The cranes are one part of the renovation of the 200-acre Ocean Terminal.

The GPA is also establishing two big ship berths at the facility, and improving the paving surface to hold container stacks.

These projects will increase to six the number of neopanamax vessels the Port of Savannah can handle simultaneously.

To work the larger ships, GPA will add eight new all electric ship-to-shore cranes at the Ocean Terminal by 2026.

When the project is complete, the terminal's annual capacity will reach two million TEU, the GPA reported.