Sustainable decommissioning of an offshore wind farm

TLDR

Offshore wind decommissioning has been overlooked, yet it poses high costs and operational challenges due to the marine environment, vessel limitations, and lack of regulations, making early, site‑specific planning essential. This study examines key operational parameters influencing decommissioning to identify their benefits and drawbacks and proposes a tailored methodology. A cost‑optimizing model compares transportation strategies, and the resulting methodology incorporates technical considerations to reduce environmental impacts. The model indicates that current site plans underestimate both the duration and costs of decommissioning.

Abstract

The offshore wind industry has historically focused on setting up new projects, with the decommissioning phase receiving little attention. This can cause future problems as decommissioning needs to be planned at the beginning to prevent complications that may arise, as it implies important operations and high costs. There are numerous features that make decommissioning a challenge, such as the marine environment, the technical limitations of vessels and the lack of specific regulations that determine what should be done, increasing the uncertainty of the process. Additionally, the unique characteristics of the sites involve exclusive optimal solutions for each project. This article analyses the main operation parameters that affect the decommissioning process, identifying the benefits and drawbacks of the influencing variables. A model is designed to compare different transportation strategies, searching for cost reduction. A decommissioning methodology is been proposed based on this analysis, taking into consideration the technical aspects of the process, and minimising environmental impacts. The model forecasts that the predicted duration and costs of this process are not being adequately captured in site decommissioning plans.