When specifying an offshore Aids to Navigation (AtoN) system, the starting point is to confirm the required marking level. Nominal range, flash character and availability are defined in line with authority guidance and the navigation risk associated with the structure.
Once those requirements are clear, attention turns to how the system will be powered. Lantern output, racon configuration and any monitoring equipment all influence the size of the supporting solar panels and battery system.
It’s common to build in additional margin during this stage. A higher-output lantern feels safer; extra battery capacity offers reassurance; and larger solar panels reduce concerns about winter performance. But these changes add up. The result can be a system that is heavier, more complex and more expensive than required.
Effective AtoN design is not about minimising equipment. It is about selecting equipment that matches the actual level of navigational risk.
Understanding Authority Requirements Before Selecting Equipment
Authority guidance is sometimes interpreted more cautiously than necessary. It can feel safer to exceed requirements to ensure nothing is missed.
However, guidance from the International Organization for Marine Aids to Navigation (IALA) are structured around defined risk categories and performance expectations. In UK waters, authorities such as the Northern Lighthouse Board and Trinity House assess structures based on traffic density, environmental visibility and hazard profile.
In many cases, meeting the defined category is sufficient. Specifying beyond that does not typically improve the outcome, but it can increase overall power demand and complexity.
How Over-Specification Impacts Offshore AtoN Power Systems
Oversizing usually doesn’t happen in one big decision. It develops gradually.
For example, selecting a lantern with a longer nominal range than required increases nightly energy consumption. That additional demand requires a larger battery. A larger battery then requires more solar capacity to maintain charge. What begins as a modest change can result in a significantly larger power package.
The same applies to other equipment. Racons are efficient, but they should be configured to suit actual operating conditions rather than left at maximum settings. Monitoring systems should provide the required reporting without incurring unnecessary power draw.
Foghorns are often the most power-intensive part of an AtoN system. They are essential in some high-risk or low-visibility locations, but if specified without clear justification, they can significantly increase the overall system size.
Each of these decisions may seem minor on its own. Together, they determine the installation’s weight, footprint, and cost.
A Structured Approach to AtoN Power Calculation
Avoiding over-specification relies on working through the design in a logical order.
Begin by confirming the required nominal range and flash character, based on the structure’s classification and the relevant authority guidance. With those requirements defined, the next step is to calculate the lantern’s average nightly energy use using its duty cycle and operating hours. This provides a realistic starting point for overall system demand.
From there, additional equipment such as racons, control panels and monitoring systems can be factored in to understand the total load. Battery autonomy should reflect how often the system can realistically be accessed for maintenance and the local environmental conditions.
Solar panels should then be sized using winter performance data for the installation location. Conditions in the North Sea differ significantly from those in southern Europe, the Middle East, or West Africa, so using location-specific data is essential.
Working through the design in this order helps ensure the system remains aligned with real operating conditions.
Why Energy Efficiency Matters in Decommissioning and Reduced-Power Environments
The effects of oversizing are often felt most during decommissioning or when an asset moves onto reduced power.
As permanent power is removed, structures typically rely on standalone solar and battery systems. In these situations, even a small increase in energy demand can affect how easy the system is to install, access and maintain.
Appropriately designed AtoN systems are lighter and easier to handle offshore. They reduce the need for additional structural changes and make routine inspection or battery replacement more straightforward.
For operators managing several late-life assets, getting the sizing right from the start helps keep installation, maintenance planning and overall project costs under control.
The Commercial Case for Proportionate AtoN Design
Getting the sizing right also makes commercial sense.
When AtoN systems are specified correctly, fewer unnecessary pieces of equipment need to be purchased and installed. The installation process is simpler, and the system is easier to manage over time.
For operators responsible for multiple offshore assets, these savings add up quickly.
Supporting Offshore AtoN System Design
Wellhead Electrical Supplies works with offshore operators and marine contractors to deliver practical AtoN solutions that meet real site requirements.
We supply lanterns matched to the required range, racons set up for the operating conditions, and audible warning systems where required. We also provide solar and battery systems designed around realistic power use, along with offshore-ready junction boxes and supporting components for straightforward installation.
By looking at the system as a whole, we help ensure equipment performs as required while keeping the setup proportionate and manageable.
Designing Efficient Offshore AtoN Systems in 2026
As offshore structures undergo life extension or decommissioning, getting the sizing right will remain critical to safe navigation.
The goal is simple: provide the right level of marking, keep the system reliable and avoid adding unnecessary complexity.
Whether you are reviewing an existing setup or planning a new AtoN installation, we can help you define the requirements and identify practical, fit-for-purpose solutions.
Contact Wellhead Electrical Supplies to discuss your project requirements.