Condition Monitoring of Floating Offshore Wind Turbine Foundations

Introduction

With up to 80 percent of the world's potential offshore wind resources located at water depths beyond the limit of the monopile, attention is turning to the prospect of floating foundations for wind turbines. A new report from DNV GL predicts that floating wind capacity will make up more than 20% of the offshore wind market by 2050.

The most significant advantage of floating wind turbines is that they can be placed in areas with the stronger and more reliable wind in deeper waters. In addition, the installation of floating wind also has significant advantages compared to bottom fixed turbines. Safe and efficient port-side assembly is possible using quay cranes, and the turbine can be tugged out to sea by smaller vessels. This makes the installation safer, and it is also better for the environment.

As with any floating offshore structure, condition and integrity are critical for the asset's uptime and safety, especially when they are potentially much physically further from inspection.

Situation and Value Proposition

The structural integrity of the wind turbine tower and its components is a critical element of the security of supply. With the stochastic nature of the load regime, a bespoke structural health monitoring system is required to monitor the integrity of both fixed and floating foundations supporting the tower.

Offshore wind turbines are deployed in remote locations and are subject to harsh operating environments. The challenging nature of these environments makes maintenance difficult and expensive and may be responsible for equipment failures.

The failures of these components can potentially lead to downtime and significant revenue loss in the offshore environment, with the cost of lost energy production ranging from £5,000 to £13,000 per day per turbine, depending on the size of the turbine. The turbine asset operation and conditions should be adequately monitored to maximise productivity and reduce LCOE.

Solution

At the core of the condition monitoring solution is Yokogawa's CI Server. CI Server is a cross-platform supervisory control and information system that integrates industrial controls systems, sensors and artificial intelligence, allowing:

1. 1. Remote operations for operational efficiency
2. 2. Asset and wide-area integration for centralising real-time and offline data
3. 3. Data-driven optimisation that builds towards computer-aided operations

CI Server SCADA, located at a remote operations centre, collects and manages the offshore asset data via Yokogawa STARDOM PLC and SMARTDAC+ GM10 data acquisition technologies. Yokogawa technologies are central to integrating, monitoring, and controlling subsystems and sensors for offshore wind energy assets' safe and stable operation.

Yokogawa's floating offshore wind turbine condition monitoring solution includes the supply of third-party sensors required to ensure the effective monitoring of all asset conditions.

Customer Case Study

Yokogawa has provided an independent condition monitoring solution for a floating offshore wind farm in Europe. The offshore wind farm consisted of 8MW wind turbines supported by Tension Legs Platforms (TLP) and Floating Sub-Structures (FSS). Yokogawa's independent condition monitoring solution integrated sensors and subsystems from marine weather, asset and fire systems condition monitoring across the offshore wind turbine assets. The Yokogawa solution includes the supply, design, engineering, testing and commissioning of a fully integrated monitoring solution.

Yokogawa's extensive offshore project management, engineering and support service experience optimises project delivery and minimises risk for offshore wind energy projects. For further information on how Yokogawa can ensure the safe and reliable operation of your offshore wind assets, contact your local office or register your interest at uk.marketing@uk.yokogawa.com.