When evaluating the business impact of converting an existing RTG terminal to automated straddle carrier operation, we like to examine the question from four areas. These are the commercial implications of the change; operational considerations; infrastructure requirements; and finally, decarbonisation. Our views on the topic are based on years of experience carrying out these kinds of conversion projects, including at some of the world's largest container terminals.

Commercial implications: Superior lifetime value

From an investment standpoint, the main difference between the RTG/TT and automated straddle carrier concepts is in the balance between capital investments and operational expenditures. RTGs served by terminal tractors have a relatively low CapEx investment for the handling capacity and performance provided by the solution. By contrast, RTG/TT terminals are extremely OpEx heavy due to the large amount of horizontal transportation equipment and operators that are required.

An automated straddle carrier terminal requires a larger initial CapEx investment but decreases OpEx by up to 80%, reducing equivalent annual cost of ownership by around 50% in a typical case. The exact details will vary based on the exact labour costs, terminal layout, and cargo mix, but the generalisation holds.

When evaluating the relative performance and capacity of the two solutions, the question becomes slightly more complex. In waterside operations, RTG/TT and automated straddle carrier solutions have been proven to deliver generally similar performance. In storage capacity, the RTG is nominally superior due to its higher stacking height; however, this is partially offset by the more efficient land use at an automated straddle carrier terminal.

In landside operations, the automated straddle carrier offers significantly better performance, mainly due to the much higher number of truck exchange lanes. In an RTG terminal, truck exchange lanes are limited to the number of RTG cranes, whereas at an automated straddle carrier terminal, the maximum number of truck lanes is limited only by available space constraints. As a result, automated straddle carrier solutions can be expected to deliver up to 2 x higher landside performance compared to RTG terminals. The automated straddle carrier solution also offers the fastest time to value of all automated solutions due to its easy and fast deployability.

Operations: One machine, one fleet, any task

For terminal operations, the most significant benefits of the AutoStrad™ concept are space efficiency, operational flexibility, and safety. An automated straddle carrier terminal uses a single type of machine for both container stacking and transportation, which allows the utilisation of corners and other irregularly shaped areas of the terminal site that would otherwise remain unproductive. Moreover, unlike manually driven straddle carriers, automated straddle carriers can drive at full speed through the stack, which reduces the need for highways in the terminal layout.

Perhaps the most dramatic benefit of an automated straddle carrier terminal is the extreme flexibility of the concept. The entire fleet is always available for use where capacity is most needed, whether at the waterside or serving the truck lanes.

Finally, AutoStrad™ terminals offer an extremely safe working environment for both terminal staff and external truck drivers. Automated and manually driven traffic are always completely separated from each other, and no mixed-mode operation takes place at the terminal. Furthermore, operators don’t need to be transported to and from the equipment during shift changes and breaks. In addition to providing direct occupational safety benefits, these factors can help terminals reduce their insurance premiums.

Infrastructure: Ready to run

When converting an RTG terminal to AutoStrad™ operation, much of the existing terminal infrastructure can be used as-is. A terminal pavement that has been designed for RTG operation will generally be fine for automated straddle carriers. Compared to manual straddle carriers, automated straddle carriers can extend the lifetime of the pavement with so-called stack shuffling, in which container stacking positions and the drive paths of the machines are incrementally varied by a few centimetres at a time, resulting in more even wear of the pavement surface.

At an AutoStrad™ terminal, existing lighting masts can serve as mounting points for positioning and communications equipment for the straddle carriers, and the wireless communication networks required by automated straddle carriers are like those already used by traditional RTGs. Automated straddle carriers don't require any lighting for the actual operations, but lighting will still be necessary for yard maintenance and other similar tasks.

A terminal converting to automated straddle carrier operation will require some additional infrastructure that is specific to the automated straddle carriers, from quay crane instrumentation to positioning systems and redesigned truck exchange lanes. However, the relatively light infrastructure requirements of automated straddle carriers make them a viable upgrade path for RTG terminals looking to move towards future electrification and automation. Electrifying an RTG crane is possible but requires the installation of heavy-duty cable reel infrastructure that will compromise the operational flexibility of the RTG concept, in which cranes can be moved from stack to stack if needed.

Decarbonisation: Charge and go

At Kalmar, we know the future of the ports and terminals industry is carbon neutral . Moving towards electrically powered container handling is one of the key steps that terminals are taking to decarbonise their on-site operations, and Kalmar Automated Straddle Carriers are ready to meet this challenge.

The hybrid AutoStrad is currently our most sold model, and for the future we are looking to our all-electric models that are available with two different battery technologies. Our high-energy battery offers 240 minutes of operation time with 45 minutes of the charging, while the high-power battery provides 45 to 50 minutes of operating time with a charge time of only five to six minutes.

When thinking about how to electrify and decarbonise an AutoStrad™ terminal, we found that the key consideration is designing the charging of the machines so that it takes place seamlessly within the operational cycles of the equipment. This kind of opportunity charging is integrated with the Kalmar One based job scheduling and routing, so that any idle time and natural breaks between container moves are always utilised optimally to charge the machines.

Based on our calculations, we estimate that a fully electric AutoStrad™ fleet would require 5 to 10% more machines than a comparable manual fleet to account for opportunity charging. However, this can be expected to be offset by the more efficient and predictable performance of the automated fleet.

Superior TCO

To summarise, the Kalmar AutoStrad™ offers a commercially attractive option for automating an existing manual RTG terminal. Despite its initially higher CapEx, the AutoStrad™ solution offers a much lower lifetime cost of ownership thanks to its radically lower operating costs. End-to-end yard automation with a single equipment type enables extremely flexible and efficient operations, and a typical RTG terminal can be modernised to AutoStrad™ application without major infrastructure-related investments.

Finally, the Kalmar AutoStrad™ solution offers batteries, driveline, control, charging and scheduling for decarbonised operations that will help terminals meet their sustainability goals far into the foreseeable future. No other equipment type can offer this combination of benefits, and the concept is suited to container terminals of almost any size, up to the largest megaterminals in the world.