Floating Offshore Wind Energy — A Review of the Current Status and an Assessment of the Prospects

Abstract

In principle, appropriately designed floating support structures need not be more massive nor costly than the jackets or tripods being deployed in German North Sea waters and elsewhere. A number of significant challenges remain, not least the current limited operating experience but also the limited availability of comprehensive design and modelling capabilities, and demonstrated and widely applicable safe and cost-effectively installation methods. This paper assesses the prospects in terms of technology principles, challenges and the potential resource.

Wind tunnel testing of the DeepWind demonstrator in design and tilted operating conditions

“…A crucial design requirement of the DeepWind concept is the limitation of heel angle within 14 [31]; even though the floating platform implements the spar technology [32] and the low centre of gravity guarantees a large overdriving moment, the rotor is expected to tilt during operation, acting as a gyro and describing an elliptical trajectory on the water plane [33]. Such issue raises several concerns about the aerodynamic behaviour of the turbine, prompting for further investigations aiming at a deeper comprehension of skewed flow VAWT operation due to a tilted rotor arrangement.…”

Aero-Hydro-Elastic Simulation of a Semi-Submersible Floating Wind Turbine

“…In this paper, the JONSWAP spectrum is used. G(ß) is defined classically as defined by [11] n<ß-ß<n (2) with ß the mean wave direction. C\{s) is a normalization coefficient.…”

“…Eor this type of platform, wave loads will be significant due to the large fioating area, and could induce relatively large motions of the structure. Therefore, minimizing wave loads action on the structure will be in the center of the conception process [2].…”

Design and Aero-Elastic Simulation of a 5MW Floating Vertical Axis Wind Turbine

“…It is commonly accepted that for offshore sites deeper than 50m, the floating platforms are more economical convenient than the monopiles, used for shallow waters [2,3]. This paper deals with the design of a wind turbine (including the support structure) for offshore floating applications.…”

“…They are essentially divided in three groups, depending on the anchoring system and in the way that they reach hydrostatic stability: barge platform, tension leg platform (TLP) and spar buoy. Some comparative analysis on the possible supporting structures for horizontal axis wind turbines (HAWTs) were carried out by Jonkman and Matha [4] and Henderson and Witch [2]. The most relevant characteristics of the three platforms can be so summarized: − The barge system achieves the stability using a very large area at the water surface.…”