Inside a mooring FEED Study: How to de-risk FPSO projects 

When planning a Floating Production Storage and Offloading (FPSO) project, the Front-End Engineering Design (FEED) study is where strategy meets precision. For mooring engineers and project managers, this phase sets the foundation for safe, efficient, and cost-effective mooring solutions.  

At its core, a mooring FEED study is about clarity - defining the technical, operational, and financial roadmap before execution begins, including:

1. Preliminary mooring and anchor design
2. Mooring installation methodology
3. Cost and schedule estimates 

Why FEED matters for FPSO mooring  

Permanent mooring systems are critical to FPSO stability and operational integrity. A well-executed mooring FEED study ensures that every design decision aligns with site conditions, regulatory requirements, and long-term performance goals.  

It’s not just about engineering calculations; it’s about anticipating challenges and mitigating risks early.  

Our integrated methodology leverages decades of experience with logistics, vessels and permanent mooring projects. By combining lessons learned with tailored solutions for each FPSO, we deliver a framework that is both robust and adaptable. 

Key components of a mooring FEED study

1. Preliminary mooring and anchor design  

The first step is developing a preliminary mooring system design tailored to project requirements and site conditions. This includes:  

• Spread and layout design: Configuring the mooring spread to suit environmental, regulatory and operational constraints.
• Validation analyses: Assessing line tensions, anchor capacities, and component selection to confirm technical feasibility.
• Environmental screening: Incorporating metocean data - waves, currents, wind - to ensure resilience under real-world conditions.
• Anchor selection: Identifying feasible anchor types and estimating preliminary sizes based on soil conditions, project logistics, and total installed cost.  

These checks confirm compliance with safety and regulatory standards while validating the operational integrity of the mooring system design.  

2. Mooring installation methodology  

Designing the mooring system is only half the equation; installing it offshore requires strategic planning. The mooring FEED study outlines:  

• High-level installation steps: Developing a storyboard of prelay and hookup operations.
• Vessel requirements: Determining minimum vessel class, capacity, and capabilities.
• Logistic considerations: Assessing transportation of mooring equipment to base ports and confirming port capabilities for heavy equipment -such as cranage, storage space, and handling. Addressing these early reduces delays and costs.
• Operational feasibility: Analysing whether the proposed methodology can be executed safely and efficiently under site conditions. 

This ensures that installation risks are identified and mitigated before mobilisation.  

3. Cost and schedule estimates  

Budget and timeline clarity are essential for project success. The mooring FEED study provides:  

• Equipment procurement costs: Obtaining quotes for permanent mooring components and estimating shipping times.
• Offshore execution schedule: Using scenario-based methodologies to forecast installation timelines.
• Total project cost estimates: Summarising costs for engineering, project management, equipment fabrication, and offshore operations.  

These estimates allow stakeholders to make informed decisions and secure resources early. 

The strategic advantage  

A mooring FEED study is more than a technical exercise; it’s a strategic investment. By addressing design, installation, cost, and schedule upfront, operators reduce uncertainty and avoid costly surprises during execution. For FPSO projects, where complexity and scale leave little room for error, this clarity is invaluable.  

Our approach is strengthened by collaboration.  

• Intermoor, Acteon’s Moorings and Anchors business line, brings  decades of mooring design and operational expertise installing mooring systems offshore. 
• 2H, Acteon’s engineering consultancy, provides domain knowledge in detailed mooring design, geotechnical analysis, and flowline design.
• UTEC, Acteon’s Geo-services business line, supports geotechnical coring using our cost-efficient PROD subsea units.  

This synergy ensures that every aspect of the mooring FEED study - from soil data to installation feasibility - is backed by proven capability.