How do you design charging schedules that align with vessel arrival patterns?

Designing charging schedules that align with vessel arrival patterns means coordinating when automated equipment is taken offline for charging with periods of lower operational demand at container terminals. This alignment matters because vessel arrivals create predictable peaks and valleys in equipment usage. By charging equipment during natural operational lulls, terminals maintain sufficient equipment availability during critical cargo handling periods whilst managing energy requirements efficiently. Proper coordination between vessel schedules and charging infrastructure planning helps terminals avoid equipment shortages during peak operations.

What does it mean to align charging schedules with vessel arrivals?

Aligning charging schedules with vessel arrivals means timing battery equipment charging to occur during periods when operational demand is naturally lower. This coordination ensures automated horizontal transport equipment, yard cranes, and other battery-powered machinery are available when vessels are alongside and cargo handling operations are at their most intensive.

The concept addresses a fundamental challenge in container terminal electrification: battery-powered equipment requires regular charging, but terminals operate continuously with minimal breaks. Vessel arrival patterns create natural cycles of high and low equipment demand:

Operational Phase	Equipment Demand	Charging Opportunity
Vessel berthed and operating	Peak utilisation	Limited to minimal
Between vessel calls	Reduced demand	Optimal charging window
Yard operations only	Moderate utilisation	Partial charging capacity

This alignment matters because research shows terminals need at least an additional 10-25 per cent of fleet when all equipment is battery powered to maintain the same operational level. You cannot charge all vehicles simultaneously, so maintaining a constant rotation of operating and charging equipment becomes necessary. However, this rotation must accommodate the reality that vessel operations create concentrated periods of high demand rather than steady utilisation throughout the day.

Energy management also depends on this coordination. Charging infrastructure represents significant capital investment, and the distribution network must handle peak charging loads. By aligning charging with vessel patterns, terminals can reduce the number of chargers required whilst maintaining adequate fleet capacity. The relationship between vessel schedules, equipment demand cycles, and charging infrastructure planning directly influences both operational performance and the financial viability of electrification projects.

Why do vessel arrival patterns matter for terminal charging planning?

Vessel arrival patterns create predictable peaks and valleys in equipment demand that determine when automated equipment can be charged without disrupting operations. Understanding these patterns allows terminals to identify charging windows during periods of lower berth occupancy, reducing the risk of equipment shortages during intensive cargo handling operations.

When vessels arrive and berth, equipment utilisation intensifies immediately. Quay cranes begin discharging and loading operations, requiring horizontal transport equipment to move containers between the quayside and yard. This creates concentrated demand that can involve more than 15 active quay cranes simultaneously at larger terminals. During these periods, taking equipment offline for charging would reduce available capacity precisely when it is most needed.

Between vessel calls, equipment demand typically decreases. Yard operations continue, but the intensive quayside movements cease temporarily. These intervals provide natural opportunities for charging equipment without compromising operational requirements. The duration and frequency of these windows depend on berth occupancy patterns, which vary based on vessel schedules, call sizes, and terminal throughput.

Impact of vessel size on charging planning

Larger vessels with bigger call sizes affect charging planning differently than smaller vessels:

Greater volume concentration: Terminals handle larger volumes during the time vessels are on berth, creating longer periods of sustained high demand
Yard absorption peaks: Exports arrive in advance and discharge operations create temporary surges that the yard must accommodate
Shorter but predictable windows: Charging opportunities may be briefer but more consistent, as larger vessels typically follow scheduled services with known arrival patterns
Extended high-demand periods: Increased call sizes mean equipment must remain operational for longer continuous periods

The connection between berth occupancy and equipment availability requirements is direct. Simulation analysis of vessel arrivals over a full year reveals how frequently charging opportunities occur and how long they last. This information determines the number of chargers required and whether additional equipment is necessary to maintain operational capacity whilst some fleet members charge. Without understanding vessel patterns, terminals risk either over-investing in charging infrastructure or experiencing equipment shortages during peak operations.

How do you map equipment utilisation to vessel schedules?

Mapping equipment utilisation to vessel schedules requires analysing historical vessel arrival data alongside equipment usage patterns to identify when demand peaks occur and when charging windows exist. This analysis tracks equipment cycles throughout the year, revealing the relationship between berth occupancy and equipment requirements across different operational scenarios.

Data collection requirements

The process begins with collecting vessel arrival data, including berthing times, departure times, vessel sizes, and cargo volumes handled. This data establishes the foundation for understanding operational cycles. You need at least one year of historical data to capture seasonal variations, as throughput patterns often fluctuate based on market conditions and shipping schedules. The data should include the number of active quay cranes per hour, as this directly indicates equipment demand intensity.

Equipment tracking involves monitoring battery-powered horizontal transport vehicles, recording when they operate and when they charge. This tracking reveals actual utilisation patterns rather than theoretical requirements:

Terminal Type	Data Collection Method	Key Considerations
Automated equipment	Terminal operating system	Straightforward data capture with integrated systems
Manually operated equipment	Deliberate tracking systems	Requires dedicated monitoring but remains necessary for accuracy

Simulation and analysis process

Berth simulation tools such as TRAFALQUAR simulate a year of vessel arrivals and quay handling operations, allowing terminals to test different scenarios. These simulations keep track of active quay cranes per hour and the number of moves executed by battery vehicles, determining energy consumption patterns over time. By simulating dynamic operations throughout the year, terminals identify when equipment capacity drops below critical threshold levels and when charging opportunities occur without compromising operational requirements.

Pattern recognition varies between terminal types:

Container terminals with scheduled services: Experience more predictable demand cycles with regular vessel arrivals and consistent handling patterns
Multipurpose terminals: Face varied cargo types and vessel sizes, creating less predictable equipment demand patterns
Bulk terminals: Equipment demand ties to berth occupancy differently than container operations, requiring specialised analysis

Utilisation analysis must account for peak periods when more than 15 cranes operate simultaneously at larger terminals. During these peaks, charging activity may need reduction to maintain sufficient vehicles for handling workload. The analysis identifies these critical periods and determines how much fleet capacity can be diverted to charging without creating operational bottlenecks. This understanding informs decisions about fleet size, charger numbers, and charging strategy.

How Portwise helps with charging schedule design

We design charging schedules that align with vessel operations through simulation analysis and capacity modelling, integrating charging infrastructure planning into terminal design and automation projects. Our approach uses advanced simulation tools to model equipment energy consumption over a full year of dynamic operations, testing different charging strategies against realistic vessel arrival patterns and operational demands.

Our methodology focuses on understanding the specific operational characteristics of your terminal. We analyse vessel schedules, berth occupancy patterns, and equipment utilisation cycles to identify optimal charging windows. Using simulation tools including TRAFALQUAR for berth operations, we model how equipment energy levels fluctuate throughout the year under different scenarios, determining the minimum charging infrastructure required whilst maintaining operational capacity above critical thresholds.

Our charging schedule optimisation services

Our services related to charging schedule optimisation include:

Energy consumption simulation: Model equipment energy usage across a full year of terminal operations, tracking battery levels and charging requirements under realistic workload conditions
Vessel pattern analysis: Examine arrival patterns and berth occupancy to identify natural charging windows aligned with operational demand cycles
Charging strategy testing: Evaluate different charging approaches, battery sizes, and charger quantities to determine optimal configurations for specific terminal operations
Power demand assessment: Analyse power requirements, including peak charging loads and frequency of maximum infrastructure utilisation
Fleet size evaluation: Determine equipment requirements when transitioning to battery-powered machinery, accounting for charging time and operational availability
Integrated infrastructure planning: Coordinate charging infrastructure with broader terminal design, automation implementation, and capacity analysis projects

We apply data-driven planning methodologies that address the industry challenges of equipment electrification, considering the wide variety of equipment types, operational time versus charging duration, and terminal-specific factors such as 24/7 operations versus shift-based regimes. Our simulation capabilities allow you to test the effects of larger vessel call sizes, which result in longer peak durations and greater charging infrastructure requirements. This analysis ensures your charging schedule design supports both current operations and future throughput growth whilst managing capital investment efficiently. Portwise Consultancy provides the expertise needed to navigate these complex operational and technical considerations.

If you’re interested in learning more, reach out to our team of experts today.

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