Review of knowledge development for the design of offshore wind energy technology

Abstract

Offshore wind energy (OWE) is one of the emerging sustainable energy sources that are currently developed under public support. In the long run, it needs to become competitive in the energy market under the same conditions as regular sources, and it is expected that engineering design can contribute significantly towards this goal. Various activities, both academic and industrial, have contributed to the knowledge base that is needed for design and technology development and the paper reviews this knowledge. The objectives of the paper are to identify points of attention for future research and to suggest directions where academic research can contribute to design improvements. The review and the suggestions do not address very specific areas of the broad range of knowledge, but rather characterizes the types of knowledge that are available and which are missing. Many research activities contribute to foundational knowledge, needed to perform simulation and analysis of provisional design solutions. Most of the design-related studies reviewed for this paper are solution oriented and contribute to contextualized knowledge. Studies that put more emphasis on methodologies largely target optimization methods. Existing knowledge appears to be weak in methodological support of the integration of the various asynchronous design processes that contribute to OWE development. The paper leads to a plea to generate such knowledge, which can be transferred from academia to industry to enhance the design strength already present in the industry. Several points of attention are given for this type of research.Offshore wind energy (OWE) is one of the emerging sustainable energy sources. Starting with the fi rst offshore wind turbine in 1990, cumulative installed power has reached nearly 1500 MW in early 2009, mainly in the waters surrounding North-West Europe. Currently, government incentives are essential to the development of offshore wind farms, but in the long run, OWE will need to become competitive in the energy market under the same conditions as regular sources. Various activities, both academic and industrial, have contributed to the knowledge base that is needed to achieve the desired performance of offshore wind farms in terms of, for instance, cost, power quality, security of supply and environmental impact. This paper reviews the types of contextualized knowledge about rotor-nacelle assemblies in the academic literature, this is one of the prominent interests in specialist literature. [19][20][21] Case studies of offshore wind farm design usually cover all aspects of design, starting with an overview of the requirements and ending with a comparison of various design options, such as in Reference 22. These studies generated knowledge about various conceptual solutions in addition to the case studies of components, sub-systems and procedures discussed above, but they also contributed to providing references for typical environmental conditions, overall requirements and expectations for system properties. They helped id...

Fragility analysis of steel and concrete wind turbine towers

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Essential mechanics issues of offshore wind power systems

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Serviceability of suction caisson founded offshore structures

“…Offshore wind turbines are very modern structures, the first offshore turbine was constructed in 1991, with large scale projects being deveolped in the early 2000s (Zaaijer, 2009), accordingly there is little operational data concerning their long-term serviceability performance. To date a significant amount of research has been conducted into the serviceability of offshore foundations.…”