The student Manu Centeno Telleria obtained an EXCELLENT CUM LAUDE grade with mention International Doctorate
The student Manu Centeno Telleria obtained an EXCELLENT CUM LAUDE grade with mention International Doctorate
The student Manu Centeno Telleria obtained an EXCELLENT CUM LAUDE grade with mention International Doctorate
- Thesis title: Supporting Strategic Decision-Making in Floating Offshore Wind Farms through a Computationally Efficient O&M-aware Techno-Economic Model
Court:
- Presidency: Jens Nørkær Sørensen (Technical University of Denmark)
- Vocal: Sofia Koukoura (Scottish Power)
- Vocal: Anna Garcia-Teruel (RWE)
- Vocal: Raúl Guanche Garcia (IH Cantabria)
- Secretary: Yerai Peña Sanchez (Mondragon Unibertsitatea)
Abstract:
The global energy transition requires the large-scale deployment of floating offshore wind (FOW) farms. To achieve this, it is essential to enhance competitiveness and promote the commercialisation of this technology by reducing costs. This process can be accelerated by supporting strategic decisions with techno-economic models that incorporate a life cycle perspective and detail the operations and maintenance (O&M) of these farms. O&M is crucial not only for its expected significant impact on the final cost but also due to the uncertainties it generates in strategic decision-making, mainly because of the limited current operational experience with FOW farms.
On the one hand, key strategic decisions involve identifying and selecting suitable sites for FOW farms, as these initial decisions shape the O&M phase and the overall profitability of a FOW project. Additionally, other key strategic decisions include the selection of ports, the fleet of O&M vessels, maintenance strategies and contracts. All these strategic decisions can be effectively supported by conducting broad sensitivity and geospatial evaluations through techno-economic models, enabling a comprehensive understanding of the potential risks and cost implications associated with different scenarios.
To conduct broad sensitivity and geospatial assessments, a techno-economic model should integrate a (i) life cycle perspective encompassing development, manufacturing, installation, O&M and decommissioning; (ii) comprehensive O&M considerations including reliability, maintainability, accessibility and availability; and (iii) computational efficiency to quickly evaluate a large number of potential scenarios. In this regard, the literature review indicates that no techno-economic model encompasses all three of these essential requirements.
To address this research gap, the main contribution of the present thesis is the development of a techno-economic model that integrates a life cycle perspective, comprehensively considers O&M aspects and has a computational efficiency. Additionally, the present thesis provides novel assessments using this technoeconomic model, offering both quantitative and qualitative insights into O&M aspects in potential areas for FOW farms, including the North Sea and the Iberian Peninsula. Results highlight that operational expenditures (OpEx), turbine downtimes and levelised cost of energy (LCoE) can vary significantly depending on the existing capability to prevent turbine failures. To achieve the OpEx levels typical of bottom-fixed offshore wind, which account for 20% to 30% of LCoE, FOW should prioritise preventive maintenance strategies.
Additionally, the results demonstrate that a comprehensive consideration of O&M aspects during site identification and selection process is essential, with turbine availability as a critical factor. In this sense, the Mediterranean Sea emerges as a promising area for FOW farms, given its less severe wave conditions that enhance maintainability.
Finally, assessments on heavy maintenance strategies underscore the potential of onsite replacement solutions to reduce turbine downtime compared to the towing strategy. However, the significant wave height operational limit for performing onsite replacements should exceed 1.5 m.