Offshore wind - Managing risks for electrical systems
Updated: Jun 12, 2023
Offshore wind is one of the front runners in the race for environmentally friendly energy sources. It is steadily expanding its application as fixed-foundation wind turbines as well as floating installations. With the Petroleum Safety Authority (PSA) assigned as the regulatory body for offshore wind developments, and the first Norwegian developments for offshore wind well on their way (Utsira Nord and Sørlige Nordsjø II), the path is paved for rapid growth. It is generating a wave of interest, not only in international waters but also in Norway.
Getting started with the Risk Management Roadmap
Identifying and assessing project risks at an early stage is paramount. Both to reduce the financial risks and risks related to delays, e.g., due to the need of taking a specific technology risk at an early stage. Therefore, a holistic approach is essential when defining a risk management framework. While the wind power converter offshore platforms are typically unmanned, electrical hazards can result in substantial asset loss. Furthermore, maintenance of high-voltage equipment poses a significant risk to the life and safety of personnel.
As part of the framework, it is advisable to perform the Electrical HAZOP (EHAZOP) of the offshore wind substation platform at an early stage. Additionally, you should also perform it during the detailed design phase of the project. At this point, it is worth mentioning, that the EHAZOP of such installation (wind power converter offshore platform) covers only the electrical systems. For the risk assessment of other systems, e.g., cooling systems, you should also perform a process HAZOP.
The 3 modules of EHAZOP
We typically divide EHAZOPs into three main studies:
Safety Analysis (SAFAN) utilizes HAZID techniques to identify hazards related to the layout and accessibility of electrical equipment.
System Security and Operability (SYSOP) follows the traditional HAZOP methodology to identify hazards related to the design, operability, and maintainability of electrical systems.
Operator Task Analysis (OPTAN) examines probable tasks to be undertaken by local and remote operators during both normal and abnormal conditions.
The application of EHAZOP on Offshore Wind Platforms
For wind power converter offshore platforms, it is recommendable that the EHAZOP covers high-power transmission systems. Additionally, it should also cover auxiliary power distribution within the platform. As for any risk assessment, interfaces between e.g., different systems or operators, onshore and offshore stations can present considerable risk. It should therefore be a part of the main focus.
For the application of the 3 modules of EHAZOP, a typical strategy is to divide the entire system into sub-systems i.e., nodes. This logical manner enables better focus and structure for the review and discussions. For example, for the SYSOP, you can divide the system by the different bus bar voltage levels.
Elaborating on the Difference
A SAFAN considers the physical layout and accessibility of electrical equipment. It also provides a critical analysis of high voltage installation hazards for personnel and equipment in the vicinity of the facilities. During SAFAN, you should discuss the following, as a minimum, for the different areas: electrocution, fire, explosion, physical danger, toxicity, and environmental.
A SYSOP is a systematic review of engineering design. You do it to identify possible limitations and lack of flexibility with their consequences on operability and overall security of the system. It is similar in method to a HAZOP analysis. The SYSOP use parameters and prompt words to identify and evaluate deviation from standard operation. As a minimum, the SYSOP should cover operation, protection, control, interfaces, maintenance, environment, and identification for the different operational modes.
Typically, you perform the OPTAN after you have completed the SAFAN and SYSOP. The focus of this analysis is the examination of the operator’s tasks when operating and maintaining electrical systems. The focus is also on the adequacy of facilities, interfaces, and competency to perform them safely without error. This study is advisable during the later stages of the project.
ORS Consulting is supporting stakeholders in multiple sectors with risk assessments of electrical systems. Any comments or questions?
