Posters

Abstract

Following the Paris climate accord, most North Sea and Baltic Sea countries have set their national targets for offshore wind deployment by 2030. Offshore wind development must, however, compete for limited space with other local interests. Recognizing this challenge, national regulatory authorities have formulated maritime spatial plans, to coordinate spatial use of their waters, and to ensure the economic and environmental compatibility of those different uses. Staying the course, the countries have then designated areas for the development of offshore wind projects. When comparing the size of these development areas against each country's national capacity target, it's possible to calculate the expected capacity density for the projects to be installed there [MW/km2]. From an engineering perspective, capacity density reflects design principles that seek to maximize array efficiency and energy production, with lower capacity density generally returning lower turbine interaction losses and maximizing energy production. In reality, though, offshore wind projects are subject to siting regulations, which vary between different countries, and strongly influence the mean wind farm capacity density. To bring it all together, WT has compiled capacity densities for a comprehensive set of operational offshore wind farms, in countries with the biggest offshore wind experience, and has compared them to the assumptions made in emerging markets, such as Poland. As well as Polish projects having one of the highest turbine capacity densities, these projects are mainly at the upper end, in terms of size (area), compared to other operational western European projects. On top of this, wind farms in Poland are being planned in clusters where neighbouring wind farms will significantly impact each other. Consequently, turbine interaction losses as well as increased wake-induced fatigue loads for downstream turbines, may lead to reduced lifetimes and/or premature damage of the asset. In other words, any marginal gains may be lost, and it might be seen an increased LCoE. This is something the industry hasn't really seen before and so, several technical innovations may be required to meet the challenges. The authors have set out to contextualize these expected capacity densities within the European markets, and discuss the technical feasibility of these, the challenges it may bring and how these can be addressed. The presentation will also provide insights as to how the following factors might impact offshore wind farm layout design: * The trend in future turbine technology; * How this translates to project capacity density for the Polish market; * What this means for the resulting impact on turbine interaction effects. Finally, the results of WT's case study will be presented to the audience showing that energy output may not be maximized with ever larger rotor diameters and that developers may want to compromise in size to achieve higher production. Attendees will then gain an understanding of how a holistic approach of multiple aspects e.g. implementation of wake management techniques (wake steering or axial induction control), careful layout design and optimization etc. may mitigate higher turbine interaction effects, reduce structural loads, extend project lifetime and, consequently decrease LCoE.