Avoiding the choke
Getting megaships to berth is just half of the equation. Upgrading crane facilities dryside and then into the hinterland is another pressing challenge. Senior ports and maritime engineer Alex To outlines the key obstacles and opportunities.
With a greater volume of containers per call to handle and with megaships expected to remain at the port on average 20% longer, it is crucial that ports plan for improvements in the handling of containers to reduce turnaround times.
An obvious solution is to deploy more ship-to-shore cranes, but this is not as simple as it sounds. Most quayside cranes are designed to be wider than container bay blocks, which means that when a crane is working, bays either side are blocked off and cannot be worked on by the adjacent crane. This issue of bay blocking requires a complete rethink of how quay cranes are built and supported at the quayside.
An example of innovative crane design, which eliminates the issue of adjacent bay blocking, is the Fastnet crane concept developed by APM Terminals, where the cranes are individually mounted on a single elevated girder supported by automated moveable pillars. This enables cranes to work on all bays of the ship.
However, the deployment of more cranes usually leads to a greater power demand for the port, which may sometimes be the key constraint.
Fresh perspectives
Finally, even if more cranes are adequately accommodated at the quayside, the full benefits may not be realised as the stowage pattern of the containers on the ship determines the actual number of cranes that can work on the vessel. An even spread of containers across the bays of the ship is required for full utilisation of quayside cranes.
The number of boxes handled per lift could be increased to improve the handling rate. Traditional crane arrangements consist either of two TEUs or a single FEU (40ft equivalent unit) utilising a single spreader and head-block.
Modern-day innovations have seen productivity of cranes improved by utilising two trolleys, increased hoist speeds and deploying tandem FEU lifting configurations using two spreaders and head-blocks. A tandem FEU configuration can essentially allow for the lifting of four TEUs, two FEUs or a combination in a single lift.
Although the handling of more containers per lift will improve quayside productivity, there are a number of associated operational factors, which need to be considered for this option to be fully beneficial. With the utilisation of tandem FEU cranes, congestion at the yard and wharf areas is likely to be exacerbated since a greater number of tractor trailers are required for each lift. To reduce congestion a tandem chassis can be employed under the crane where four TEUs or two FEUs can be transported per tractor-trailer. The main disadvantage of a tandem chassis is that the terminal layout might have to be reconfigured to accommodate the larger and wider tracker trailer system.
Scaling the peaks
Quayside handling efficiency doesn’t finish the jigsaw. Once the quayside matches the demands of the megaship, the efficiency of the terminal yard must also accommodate quayside operations. The biggest impact on yard side operations will be the increase in operational peaks and the duration of these peaks. The throughput may only be marginally more with megaships, but the little-and-often pace of before is replaced by massive-but-less.
How do operators cope with the need to perform faster in peak times of activity, and make the most of downtime? Megaships will be quayside for 20% longer, but the incentive to get them out quicker – closer to 60 TEU an hour than 40 – not least to avoid demurrage – is increasingly important.
The right models and solutions can help clients make better use of downtime to organise stacking so that containers are more quickly stored, registered and moved on, so that the megaships are turned around quicker. Ports will also welcome more than megaships, so it’s important not to over-focus on these giants, which may not visit every day. Port optimisation is therefore valuable exercise.
Storage capacity is one of the key choke points of the container terminal, and should be increased where possible. Long container dwell times can also have a telling impact on yard storage capacity. However, to reduce dwell times, significant alterations in port administration and cross-organisational procedures are required, which may not be easily achievable.
Well-established ports are sometimes unable to increase appreciably in size as they are limited by adjacent infrastructure, urban development or areas of environmental/ecological importance. Where onsite storage can’t be increased, inland depots or dry ports can provide relief to congested terminals, especially if multimodal transportation is also utilised.
Beyond the fence line
Ports operators should ask themselves: are local transport links sufficient to allow for the greater volume of containers passing through the port? In the UK, where ports are privatised, operators are asked to contribute to the cost of upgrading local transport links as a result of port upgrades. Working with local authorities and national transport agencies is crucial to ensuring local infrastructure can accommodate more frequent peaks in port movements such as those that occur when megaships call to port.
By getting the masterplan right from the start, ports can avoid bottlenecks down the line. But often, the more practical and affordable solution is to assess the limitations, adapt existing infrastructure and then integrate them to create a system that works.