Mathematical Optimization and Algorithms for Offshore Wind Farm Design: An Overview

Wind energy is a fast evolving field that has attracted a lot of attention and investments in the last dec- ades. Being an increasingly competitive market, it is very important to minimize establishment costs and increase production profits already at the design phase of new wind parks. This paper is based on many years of collaboration with Vattenfall, a leading wind energy developer and wind power operator, and aims at giving an overview of the experience of using Mathematical Optimization in the field. The paper illustrates some of the practical needs defined by energy companies, showing how optimization can help the designers to increase production and reduce costs in the design of offshore parks. In particular, the study gives an overview of the individual phases of designing an offshore windfarm,andsomeoftheoptimizationproblemsinvolved. Finally it goes in depth with three of the most important optimization tasks: turbine location, electrical cable routing and foundation optimization. The paper is concluded with a discussion of future challenges

Utsira Nord Floating Wind farm – Optimalisation of marine operations related to inter-array cable installation.

The offshore wind industry is experiencing significant growth, with wind farms expanding in size, capacity, and moving to more challenging locations. However, cable faults remain a major concern, particularly during the installation of inter-array and export cables. This thesis aims to research and analyse the installation steps of inter-array cables at the Utsira Nord offshore wind farm. It further seeks to enhance the installation process by identifying functional sea states through a combination of previous work and new data. The research focuses on answering key questions related to the installation of inter-array cables. This includes identifying the main steps, defining critical phases, and analysing the typical loads that impact cable installation to determine the parameters affecting the process. Additionally, the thesis seeks to determine the optimal environmental conditions for cable installation. The methodology employed in this thesis includes literature studies, experience from employees at DeepOcean regarding offshore operations, and the use of Orcaflex and Excel. The analysis, primarily conducted using Orcaflex, concentrates on the installation of 1st and 2nd end dynamic section. The floating windmill is treated as a fixed structure in the Orcaflex model, neglecting its movement due to the ongoing development of the foundation concept and limited comprehensive information on weather and environmental factors. The study primarily focuses on tension and curvature acting on the cable during installation, disregarding boat and floating structure considerations that are not directly relevant to the research objectives. From the knowledge gained in the literature review, an analysis was carried out to investigate crucial parameters in the cable laying process and a conclusion for when it is optimal to do inter-array cable installation operations at Utsira Nord was given. The focus was on tension loads, minimum bending radius, and potential clashes with the Moonpool. This was conducted with both Gumbel and Rayleigh analysis with irregular vessel motions. The result of the analysis illustrated the extent of impact the various environmental wave conditions had on the system. Throughout the study, certain wave conditions were found to be more favourable than others. Wave directions ranging from 90-135° and 225-270°, simulated with a current velocity of 0.3 m/s, offered the most optimal conditions for cable installation. In contrast, the analysis showed that sea states with wave directions of 0° and 180°, as well as current at 1.0 m/s, presented a higher risk of cable damage. To enhance the findings of this master's thesis, further analysis of different current velocities is recommended to identify operable sea states under higher currents. Additionally, analysing the system with a moving floating wind turbine, given that sufficient data is available

iCity. Transformative Research for the Livable, Intelligent, and Sustainable City

This open access book presents the exciting research results of the BMBF funded project iCity carried out at University of Applied Science Stuttgart to help cities to become more liveable, intelligent and sustainable, to become a LIScity. The research has been pursued with industry partners and NGOs from 2017 to 2020. A LIScity is increasingly digitally networked, uses resources efficiently, and implements intelligent mobility concepts. It guarantees the supply of its grid-bound infrastructure with a high proportion of renewable energy. Intelligent cities are increasingly human-centered, integrative, and flexible, thus placing the well-being of the citizens at the center of developments to increase the quality of life. The articles in this book cover research aimed to meet these criteria. The book covers research in the fields of energy (i.e. algorithms for heating and energy storage systems, simulation programs for thermal local heating supply, runtime optimization of combined heat and power (CHP), natural ventilation), mobility (i.e. charging distribution and deep learning, innovative emission-friendly mobility, routing apps, zero-emission urban logistics, augmented reality, artificial intelligence for individual route planning, mobility behavior), information platforms (i.e. 3DCity models in city planning: sunny places visualization, augmented reality for windy cities, internet of things (IoT) monitoring to visualize device performance, storing and visualizing dynamic energy data of smart cities), and buildings and city planning (i.e. sound insulation of sustainable facades and balconies, multi-camera mobile systems for inspection of tunnels, building-integrated photovoltaics (BIPV) as active façade elements, common space, the building envelopes potential in smart sustainable cities)

Automated Mixed Traffic Vehicle (AMTV) technology and safety study

Technology and safety related to the implementation of an Automated Mixed Traffic Vehicle (AMTV) system are discussed. System concepts and technology status were reviewed and areas where further development is needed are identified. Failure and hazard modes were also analyzed and methods for prevention were suggested. The results presented are intended as a guide for further efforts in AMTV system design and technology development for both near term and long term applications. The AMTV systems discussed include a low speed system, and a hybrid system consisting of low speed sections and high speed sections operating in a semi-guideway. The safety analysis identified hazards that may arise in a properly functioning AMTV system, as well as hardware failure modes. Safety related failure modes were emphasized. A risk assessment was performed in order to create a priority order and significant hazards and failure modes were summarized. Corrective measures were proposed for each hazard

iCity. Transformative Research for the Livable, Intelligent, and Sustainable City

This open access book presents the exciting research results of the BMBF funded project iCity carried out at University of Applied Science Stuttgart to help cities to become more liveable, intelligent and sustainable, to become a LIScity. The research has been pursued with industry partners and NGOs from 2017 to 2020. A LIScity is increasingly digitally networked, uses resources efficiently, and implements intelligent mobility concepts. It guarantees the supply of its grid-bound infrastructure with a high proportion of renewable energy. Intelligent cities are increasingly human-centered, integrative, and flexible, thus placing the well-being of the citizens at the center of developments to increase the quality of life. The articles in this book cover research aimed to meet these criteria. The book covers research in the fields of energy (i.e. algorithms for heating and energy storage systems, simulation programs for thermal local heating supply, runtime optimization of combined heat and power (CHP), natural ventilation), mobility (i.e. charging distribution and deep learning, innovative emission-friendly mobility, routing apps, zero-emission urban logistics, augmented reality, artificial intelligence for individual route planning, mobility behavior), information platforms (i.e. 3DCity models in city planning: sunny places visualization, augmented reality for windy cities, internet of things (IoT) monitoring to visualize device performance, storing and visualizing dynamic energy data of smart cities), and buildings and city planning (i.e. sound insulation of sustainable facades and balconies, multi-camera mobile systems for inspection of tunnels, building-integrated photovoltaics (BIPV) as active façade elements, common space, the building envelopes potential in smart sustainable cities)

On the optimization of offshore wind farm layouts

Layout optimization of offshore wind farms seeks to automate the design of the wind farm and the placement of wind turbines such that the proposed wind farm maximizes its potential. The optimization of an offshore wind farm layout therefore seeks to minimize the costs of the wind farm while maximizing the energy extraction while considering the effects of wakes on the resource; the electrical infrastructure required to collect the energy generated; the cost variation across the site; and all technical and consenting constraints that the wind farm developer must adhere to. As wakes, electrical losses, and costs are non-linear, this produces a complex optimization problem. This thesis describes the design, development, validation, and initial application of a new framework for the optimization of offshore wind farm layouts using either a genetic algorithm or a particle swarm optimizer. The developed methodology and analysis tool have been developed such that individual components can either be used to analyze a particular wind farm layout or used in conjunction with the optimization algorithms to design and optimize wind farm layouts. To accomplish this, separate modules have been developed and validated for the design and optimization of the necessary electrical infrastructure, the assessment of the energy production considering energy losses, and the estimation of the project costs. By including site-dependent parameters and project specific constraints, the framework is capable of exploring the influence the wind farm layout has on the levelized cost of energy of the project. Deploying the integrated framework using two common engineering metaheuristic algorithms to hypothetical, existing, and future wind farms highlights the advantages of this holistic layout optimization framework over the industry standard approaches commonly deployed in offshore wind farm design leading to a reduction in LCOE. Application of the tool to a UK Round 3 site recently under development has also highlighted how the use of this tool can aid in the development of future regulations by considering various constraints on the placement of wind turbines within the site and exploring how these impact the levelized cost of energy