Decision making under uncertainty for construction management of offshore wind assets

Leontaris, G (2021) Decision making under uncertainty for construction management of offshore wind assets. PhD thesis, Delft University of Technology, Netherlands.

Abstract

Offshore wind is expected to be one of the important contributors to the energy transition towards a more renewable and sustainable energy future. This can be clearly seen from the amount of investments over the past years as well as from the substantial upcoming offshore wind projects in the years to come. Many technological implementation challenges have already been addressed, but the number of new challenges will continue to increase. Especially, as the industry continues moving further offshore with larger wind turbines and as the existing offshore wind farms will approach the end of their service lives. Therefore, the need for improved asset management modelling over the entire service life from design towards decommissioning will continue increasing to support better data driven decision making under uncertainty. For this and in particular for the construction management of offshore wind assets, in this thesis new models and methods have been developed to support this enhanced decision making. These decisions are subject to various types of risks and uncertainties, varying from environmental uncertainties, supply chain disruptions and stochasticity of construction activities' duration. Therefore, these should be properly taken into account in construction management models using performance and/or expert data from past construction projects. In this thesis two types of data availability have been distinguished: (i) where sufficient relevant performance data is available and (ii) where relevant past performance data is rather limited. In the first case, statistical methods are used, such as Copula functions to model the dependence between metocean variables and Bayesian Networks to model the dependence between subsequent construction activities. In the second case, expert knowledge and data are used to quantify the uncertainty using a mathematical aggregation method for expert judgments (i.e. Cooke's classical modelling). The different methods have been applied to several test cases to investigate the associated cost and time impact. As a result of this research, different tools and an open-source software were developed. These also can be used in different fields of application using this proper mathematical expert judgment aggregation modelling. Finally, it can be concluded that the state-of the art developments within this thesis substantially contribute to decision making under uncertainty, so that construction management strategies are optimized and thereby the offshore wind energy assets life cycle value is maximized.

Item Type: Thesis (Doctoral)
Uncontrolled Keywords: offshore wind; construction management; decision making; uncertainty; risk; asset management; copula functions; bayesian networks; expert judgment
Index terms: decommissioning, life cycle value, implementation, modelling, statistical method, construction project, asset management, construction activity, service life, duration, sustainable energy, bayesian network, management strategy, judgment, data-driven decision-making, decision-making, environmental uncertainty, test case
Subjects: value management, construction operations, project controls, dispute resolution, asset management, contractual arrangements, probabilistic model, decision analysis, professional practice, renewable energy, financial risk, renovation and retrofit, analytical methods, management, statistical analysis, production management
Topics: Sustainability, Research Practice, Legal Issues, Business Strategy, Time Control, Engineering Principles, Digital Applications, Risk Management, Procurement, Cost Management, Site Management, Project Management
Descriptive scope: 3 PCA

N.B. Descriptive scope is a count of how many of the five facets of empirical research are indicated by the words used in title, abstract and keywords. It is not intended as a judgement on the research; merely a count of the kind of word we would expect to indicate Phenomenon, Concepts, Theoretical framing, Empirical techniques, Analytical techniques. If all five are present, then a code of “5 PCTEA” will indicate this. If you feel the coding for this record is questionable, we welcome discussion around the terms we matched or the way we categorized them. The facet you would expect may not be coded, or a facet may be coded inappropriately. This can also bear on a larger question, of which facets should be treated as defining in construction management research. Please get in touch, and we will look at it. More details here