Optimisation of Offshore Wind Farms Using a Genetic Algorithm

A modular framework for the optimisation of an offshore wind farm using a discrete genetic algorithm is presented. This approach uses a bespoke grid generation algorithm to define the discrete positions that turbines may occupy thereby implicitly satisfying navigational and search and rescue constraints through the wind farm. The presented methodology takes a holistic approach optimising both the turbine placement and inter-array cable network, while minimising the levelised cost of energy and satisfying real world constraints. This tool therefore integrates models for the assessment of the energy production including wake losses; the optimisation of the inter-array cables; and the estimation of costs of the project over the lifetime. This framework will allow alternate approaches to wake and cost modelling as well as optimisation to be benchmarked in the future

Techno-economic optimisation of offshore wind farms based on life cycle cost analysis on the UK

In order to reduce the cost of energy per MWh in wind energy sector and support investment decisions, an optimisation methodology is developed and applied on Round 3 offshore zones, which are specific sites released by the Crown Estate for offshore wind farm deployments, and for each zone individually in the UK. The 8-objective optimisation problem includes five techno-economic Life Cycle Cost factors that are directly linked to the physical aspects of each location, where three different wind farm layouts and four types of turbines are considered. Optimal trade-offs are revealed by using NSGA II and sensitivity analysis is conducted for deeper insight for both industrial and policy-making purposes. Four optimum solutions were discovered in the range between £1.6 and £1.8 billion; the areas of Seagreen Alpha, East Anglia One and Hornsea Project One. The highly complex nature of the decision variables and their interdependencies were revealed, where the combinations of site-layout and site-turbine size captured above 20% of total Sobol indices in total cost. The proposed framework could also be applied to other sectors in order to increase investment confidence

A multi-objective optimisation approach applied to offshore wind farm location selection

This paper compares the three state-of-the-art algorithms when applied to a real-world case of the wind energy sector. Optimum locations are suggested for a wind farm by considering only Round 3 zones around the UK. The problem comprises of some of the most important techno-economic life cycle cost-related factors, which are modelled using the physical aspects of each wind farm location (i.e., the wind speed, distance from the ports, and water depth), the wind turbine size, and the number of turbines. The model is linked to NSGA II, NSGA III, and SPEA 2 algorithms, to conduct an optimisation search. The performance of these three algorithms is demonstrated and analysed, so as to assess their effectiveness in the investment decision-making process in the wind sector, more importantly, for Round 3 zones. The results are subject to the specifics of the underlying life cycle cost model

Feasibility Analysis of Floating Offshore Wind in Svalbard

Svalbard is a Norwegian island archipelago located far north in the Arctic with Longyearbyen its largest settlement. Fossil fuel in the form of diesel generators or coal power plants is still the primary energy source in all the settlements of Svalbard. In 2018, The Ministry of Petroleum and Energy (MPE) commissioned a study on the future energy supply options for Svalbard. This study did not explore offshore wind, and considered onshore turbines to have lower cost, with similar environmental consequences. Recently, policy has restricted the future development of onshore wind turbines as a result of local opposition and concern over sensitive bird populations. Floating offshore wind (FOW) could be considered as an alternative and the feasibility of such a project should be investigated further. As such, the purpose of this study is to investigate the feasibility of FOW in Svalbard. This was done through a case study, which is limited to the installation and operational feasibility of a semi-submersible FOW concept layout of six 12MW WINDMOOR units positioned 60km offshore from the entrance at Isfjorden. Reference literature on the subject is scarce, so typical arctic offshore engineering challenges are explored to aid the analysis. Typical and extreme site conditions and challenges encountered with arctic offshore installations is of great interest to the case study. Of these challenges, sea ice was identified as a critical environmental condition for the installation and operation of offshore structures in the arctic. At the selected site however, due to the warmer and more favourable climate conditions on the west coast of Svalbard, sea ice is expected to be small and in low concentrations. The concept was then tested for the expected extreme ice conditions at the site using the Simulator for Arctic Marine Structures (SAMS) program. The results from the SAMS simulation that replicated adverse sea ice conditions on the FOW concept showed that sea ice would likely be a minor issue and not impact on the stability of the semi-submersible structure. This provides greater confidence that one of the major challenges in the arctic would not be a significant issue at the selected site. The threat from icebergs was also considered, which would need to be monitored and managed should the project progress. A high-level installation downtime assessment was conducted using Shoreline, a simulation tool for the programming and optimisation of offshore wind construction projects. From the results of the simulation, weather conditions during summer are favourable for the delivery of the project and downtime due to waiting on weather would be limited. From a constructability perspective, the project is possible. The study showed that the FOW concept would be able to meet the energy needs of Longyearbyen. However, while FOW is feasible in Svalbard from an engineering perspective, a business case analysis should be conducted for the selection of the alternative energy system. It is likely that this project may be too costly for any funding to be secured in the immediate future. The cost is projected to decrease which could make this a more attractive option within the decade. The onshore assembly of FOW units combined with long distance towing operations has been achieved before in Norway for a similar scale project. The concept would also be dependent on the future environmental policy as well as conflicts with stakeholders in tourism, fishing, and shipping. More research is required to progress the FOW concept to development. The most critical information required would be a detailed cost estimate enabling a business case analysis to be conducted. A preliminary cost assessment however indicates that electricity costs from FOW would be competitive against other forms of energy. This would ultimately decide the fate of the project. Stakeholder engagement and an environmental impact assessment would also need to be conducted for the project

On using simulation to model the installation process logistics for an offshore wind farm

The development of offshore wind farms (OWFs) in Europe is progressing to sites which are characteristically further from shore, in deeper waters, and of larger scale than previous sites. A consequence of moving further offshore is that installation operations are subject to harsher weather conditions, resulting in increased uncertainty in relation to the cost and duration of any operations. Assessing the comparative risks associated with different installation scenarios and identifying the best course of action is therefore a crucial problem for decision makers. Motivated by collaboration with industry partners, we present a detailed definition of the OWF installation process logistics problem, where aspects of fleet sizing, composition, and vessel scheduling are present. This article illustrates the use of simulation models to improve the understanding of the risks associated with logistical installation decisions. The developed tool employs a realistic model of the installation operations and enables the effect of any logistical decision to be investigated. A case study of an offshore wind farm installation project is presented in order to explore the impact of key logistical decisions on the cost and duration of the installation, and demonstrates that savings of up to 50% can be achieved through vessel optimization

Exploring the impact of innovative developments to the installation process for an offshore wind farm

For offshore wind to be competitive with mature energy industries, cost efficiencies must be improved throughout the lifetime of an offshore wind farm (OWF). With expensive equipment hire spanning several years, installation is an area where large savings can potentially be made. Installation operations are subject to uncertain weather conditions, with more extreme conditions as OWF developments tend towards larger sites, further offshore in deeper waters. One approach to reduce the cost of the installation process is to evaluate advanced technologies or operational practices. However, in order to demonstrate cost savings, the impact of these advances on the installation process must be quantified in the presence of uncertain environmental conditions. To addresses this challenge a simulation tool is developed to model the logistics of the installation process and to identify the vessels and operations most sensitive to weather delays. These operations are explored to identify the impact of technological or operational advances with respect to weather delays and the resulting installation duration under different levels of weather severity. The tool identifies that loading operations contribute significantly to the overall delay of the installation process, and that a non-linear relationship exists between vessel operational limits and the duration of installation

How Important Are Ports for the Offshore Wind Industry?: The Case of Spain

Paper: 19th International Conference on Renewable Energies and Power Quality (ICREPQ’21) Almeria (Spain), 28th to 30th July 2021[Abstract] Offshore wind is becoming a new technology to develop a better sustainable world. Its progress is linked to the use of port facilities, where the offshore wind farms can be stored or pre-installed. The aim of this paper is to analyse the storage space availability for ports in terms of being used for the new offshore wind sector. The case of study will be focused on analysing the port facilities in Spain, country with a great offshore wind resource in some specific areas. Results indicate the ports that can be used for the development of offshore wind in Spain. This work is important in order to establish a roadmap of the offshore wind business in Spain, which can repair the economic and social damaged due to SARS-CoV-2 pandemic.This research was funded by Project PID2019-105386RA-I00 “Design of a tool for the selection of offshore renewable energy locations and technologies: application to Spanish territorial waters (SEARENEW)”, financed by Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación/10.13039/50110001103

Robust Rolling Horizon Optimisation Model for Offshore Wind Farm Installation Logistics

Our approach can be considered as both proactive and reactive, since uncertainty is considered both in creating the initial schedule and the schedule can be updated in real-time