Innovative Wind Conversion Systems (10-20 MW) for Offshore Applications


Funding:   German Federal Ministry for Economics Affairs and Energy (BMWi)
Partners: Technical University of Denmark, DHI Denmark, TUDelft, University of Stuttgart, Aalborg University, University of Hanover, University of Oldenburg, WMC Netherlands, Fraunhofer-Gesellschaft Germany, Rambøll Germany
Duration: 11/2012 - 12/2017



The overall objectives of the INNWIND.EU project are the high performance innovative design of a beyond-state-of-the-art 10-20 MW offshore wind turbine and the hardware demonstrators of some of its critical components ( The overall project consists of six work packages (WP) and a total of 27 European partners. The Fraunhofer IWES is involved in WP 1 and WP 4.

WP 1 - Conceptual Design. The WP1 focuses on conceptual design of wind turbines in the range of 10 MW -20 MW and serves as the integrating work package which assembles the component innovations at the wind turbine level and assesses their performance. The key performance indicators, environmental conditions, design drivers and turbine control systems are developed within this work package.

Within WP 1, Fraunhofer IWES is involved in Task 1.1 - External Conditions. Task 1.1 deals with the external conditions and aims at providing the missing information on the external conditions at higher atmospheres which is needed for designing large offshore wind turbines.

Fraunhofer IWES delivers an overview about available data sets, including a description of the measurement sites, the data sources and the access options. Further, exemplary characteristic data sets are defined and delivered. These include selected processed data for a specific period which are available for interested INNWIND.EU partners. The data sets shall comprise rather standard conditions as well as conditions significantly deviating from these.


WP 4 – Offshore Support Structures. The aim of WP 4 is to achieve innovative jacket designs in the 10 MW class in terms of enabling at least 20% cost reduction compared to current designs by innovations on the components level. Furthermore, risks and possibilities shall be assessed and a preliminary design of an innovative 20 MW substructure will be developed. In addition, numerical models of non-linear floater behavior will be validated in wave tank tests and first floater concept designs will be delivered to speed up their time to market.

Within WP 4, Fraunhofer IWES is involved in Task 4.1 - Innovations on component level for bottom-based structures. This task aims at developing innovations on component level to lower the costs of energy for 10 MW OWT to a competitive level. The component levels within this task cover all relevant topics of future cost-effective, mass-producible designs (e.g. casted joints and industry-standard piles), such as new foundation types (without grout and/or piling), soil-structure-interaction of large piles or suction buckets, innovative transition piece designs or designs consisting of hybrid materials never used in wind energy before. In addition, design integration using jacket-specific controls and innovative fabrication and installation processes shall complete the overall cost saving potentials. Another major part of this task is the validation by testing. Within the given framework scale-tests of innovative joints and hybrid materials but also validation of soil-structure interactions will be realized.

Fraunhofer IWES focuses on soil-structure interaction of predominantly axially loaded piles. Here, the main objective is to improve the accuracy of model predictions and to validate the analytic and numerical models by experimental tests.