Modelling analysis of maintenance logistics optimization for a floating wind park: A case study for Utsira Nord

The global society is part of a climate challenge that requires the development of will, understanding and technology. The United Nations has given the climate challenge its sustainability goal, saying, "Goal 13: Take urgent action to combat climate change and its impacts" [1]. There will not be sufficiently developed energy production today in the context of future electrification of the Norwegian everyday life and industry. Norway needs to invest in more green energy production not to become an import nation of energy, but; an export nation. On June 12th, 2020, the Utsira Nord area was opened by the Government by royal decree for energy production from floating offshore wind [2]. By taking a closer look at the well-known concept of Operating expenditures, one can see clear advantages and challenges related to floating offshore wind [3]. It shows how important it is to optimise the maintenance strategy for the industry, and this is the basis for this thesis. There are many logistics solutions, and many factors influencing the choice that is hard to know beforehand. Therefore, it will depend on each wind farm to decide the best alternative to provide maintenance services. Hence, this thesis aims to investigate the following questions: • How to utilize modelling and simulation method for selection of optimal maintenance logistics strategy for a wind farm at Utsira Nord • What will be an optimal maintenance logistics strategy for an imaginary Utsira Nord wind farm, seen from cost-benefit perspective and emission perspective A case study has been carried out based on an imaginary wind farm at Utsira Nord to answer the research questions. Shoreline software is used to create simulations, and analyses potential technical solutions. The research is executed in the following steps: (1) extract stakeholder requirements and acceptance criteria and define the purpose of the simulation model, (2) systems analysis of the wind park, maintenance program and logistic vessels, (3) collect and extract failure and maintenance data from existing offshore wind parks, (4) collect technical and economic data for several logistic maintenance vessels, (5) design and prepare the simulation cases, (6) perform the simulation cases and visualise the results, (7) verification and validation, including sensitivity analysis and (8) evaluate and select the most optimal logistic vessel alternative based on cost/availability and emissions When it comes to the most optimal vessel for the case wind park, the result clearly shows that the service operation vessel provides more benefits in terms of overall grading for cost/availability and emissions. It comes out far better than the crew transfer vessel because of the sensitivity associated with the maximum wave height for this vessel. This causes a significantly higher downtime for the wind farm, and the analysis shows that the case can increase its turnover by € 13,844,000 by using a service operation vessel in favour of a crew transfer vessel concerning lost production. The method used to carry out the analysis and simulation can be used as a starting point to provide the most optimal maintenance logistics strategy for each park. It can be common service operation vessel for several parks within the same field, several crew transfer vessels or make use of other logistical possibilities such as helicopters

Modelling analysis of maintenance logistics optimization for a floating wind park: A case study for Utsira Nord

The global society is part of a climate challenge that requires the development of will, understanding and technology. The United Nations has given the climate challenge its sustainability goal, saying, "Goal 13: Take urgent action to combat climate change and its impacts" [1]. There will not be sufficiently developed energy production today in the context of future electrification of the Norwegian everyday life and industry. Norway needs to invest in more green energy production not to become an import nation of energy, but; an export nation. On June 12th, 2020, the Utsira Nord area was opened by the Government by royal decree for energy production from floating offshore wind [2]. By taking a closer look at the well-known concept of Operating expenditures, one can see clear advantages and challenges related to floating offshore wind [3]. It shows how important it is to optimise the maintenance strategy for the industry, and this is the basis for this thesis. There are many logistics solutions, and many factors influencing the choice that is hard to know beforehand. Therefore, it will depend on each wind farm to decide the best alternative to provide maintenance services. Hence, this thesis aims to investigate the following questions: • How to utilize modelling and simulation method for selection of optimal maintenance logistics strategy for a wind farm at Utsira Nord • What will be an optimal maintenance logistics strategy for an imaginary Utsira Nord wind farm, seen from cost-benefit perspective and emission perspective A case study has been carried out based on an imaginary wind farm at Utsira Nord to answer the research questions. Shoreline software is used to create simulations, and analyses potential technical solutions. The research is executed in the following steps: (1) extract stakeholder requirements and acceptance criteria and define the purpose of the simulation model, (2) systems analysis of the wind park, maintenance program and logistic vessels, (3) collect and extract failure and maintenance data from existing offshore wind parks, (4) collect technical and economic data for several logistic maintenance vessels, (5) design and prepare the simulation cases, (6) perform the simulation cases and visualise the results, (7) verification and validation, including sensitivity analysis and (8) evaluate and select the most optimal logistic vessel alternative based on cost/availability and emissions When it comes to the most optimal vessel for the case wind park, the result clearly shows that the service operation vessel provides more benefits in terms of overall grading for cost/availability and emissions. It comes out far better than the crew transfer vessel because of the sensitivity associated with the maximum wave height for this vessel. This causes a significantly higher downtime for the wind farm, and the analysis shows that the case can increase its turnover by € 13,844,000 by using a service operation vessel in favour of a crew transfer vessel concerning lost production. The method used to carry out the analysis and simulation can be used as a starting point to provide the most optimal maintenance logistics strategy for each park. It can be common service operation vessel for several parks within the same field, several crew transfer vessels or make use of other logistical possibilities such as helicopters

Fish investigations in the Barents Sea Winter 2023

Preface Annual catch quotas and other regulations of the Barents Sea fisheries are set through negotiations between Norway and Russia. Assessment of the state of the stocks and quota advice are given by the International Council for the Exploration of the Sea (ICES). Their work is based on survey results and international landings statistics. The results from the demersal fish winter surveys in the Barents Sea are an important source of information for the annual stock assessment. The development of the survey started in the early 1970s and focused on acoustic measurements of cod and haddock. Since 1981 it has been designed to produce both acoustic and swept area estimates of fish abundance. Some development has taken place since then, both in area coverage and in methodology. The development is described in detail by Jakobsen et al . (1997), Johannesen et al . (2009) and in Appendix 3, and the current survey design and methods for survey index calculation are presented in Appendix 2. The survey manual is available at the internal IMR quality portal here. At present the survey provides the main data input for several ongoing projects at the Institute of Marine Research, Bergen: monitoring abundance of the Barents Sea demersal fish stocks mapping fish distribution in relation to climate and prey abundance monitoring food consumption and growth estimating predation mortality caused by cod This report presents the main results from the surveys in January-March 2023. The surveys were performed with the Norwegian research vessels “Kronprins Haakon” and “Johan Hjort”, and the Russian research vessel “Vilnyus”. Annual survey reports since 1981 are listed in Appendix 5, and names of scientific participants in 2023 are given in Appendix 4.Fish investigations in the Barents Sea Winter 2023publishedVersio