Development of CIRCular optimised material solutions for WIND turbine blades and support structures

Project Information

CIRCWIND

Grant agreement ID: 101147517

DOI

10.3030/101147517

EC signature date 2 August 2024

Start date 1 October 2024

End date 30 September 2028

Funded under

• Climate, Energy and Mobility

Total cost

€ 3 999 662,50

EU contribution

€ 3 999 662,50

Coordinated by

SINTEF AS
Norway

Periodic Reporting for period 1 - CIRCWIND (Development of CIRCular optimised material solutions for WIND turbine blades and support structures)

Reporting period: 2024-10-01 to 2026-03-31

Summary of the context and overall objectives of the project

Wind energy is a cornerstone of the European Green Deal and a key pillar of the EU strategy for climate neutrality by 2050. To meet rapidly increasing renewable energy targets, wind turbines are becoming significantly larger, particularly in offshore and floating applications. At the same time, a growing number of existing wind turbines are approaching their end of life, creating urgent challenges related to reliability, lifetime extension, decommissioning, and the circular use of materials. Failures of critical components such as blades and support structures can lead to high operation and maintenance costs, reduced energy production, and increased environmental impacts. Current materials and design approaches are increasingly reaching their limits under more demanding operating conditions and accelerated innovation cycles.
In this context, CIRCWIND addresses the need for enabling technologies that improve the reliability, lifetime, and circularity of wind energy systems, in line with EU energy and industrial strategies. The project focuses on two critical wind turbine components: blades and floating substructures. Its main objective is to develop and validate innovative, damage‑tolerant and circular materials, together with advanced modelling, simulation, and monitoring tools that increase reliability, extend service life, and reduce environmental footprint.
CIRCWIND combines new fibre‑reinforced polymer (FRP) materials for blades, low‑carbon geopolymer concrete for floating substructures, and virtual replica approaches enabling predictive maintenance and life‑extension strategies.
The project pathway to impact is based on the integration of:
(i) material innovation,
(ii) advanced modelling and simulation,
(iii) experimental validation, and
(iv) sustainability and cost assessment,
targeting a technology readiness level up to TRL 5.
By reducing unexpected failures, lowering maintenance needs, and enabling lifetime extension and circular material loops at end of life, CIRCWIND contributes to improving reliability and reducing the levelised cost of wind energy, thereby supporting the sustainable expansion of offshore and onshore wind power in Europe.
Social sciences and humanities are integrated through life‑cycle costing, social life‑cycle assessment, and stakeholder engagement, ensuring that technological developments are aligned with societal acceptance, economic viability, and responsible deployment.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the first phase of the project, CIRCWIND has established a solid technical and methodological foundation. Requirements for a representative 15 MW offshore wind turbine and its floating support structure were defined, including load scenarios, environmental conditions, circularity targets, and cost drivers. These specifications provide a common reference framework for all subsequent technological developments.
For wind turbine blades, specialised experimental setups have been developed to investigate fatigue crack growth and damage mechanisms under realistic loading conditions. Initial microscale investigations and multiscale modelling activities have been initiated, enabling improved understanding of damage evolution in composite materials and how it can be mitigated through optimised material design and manufacturing processes. In addition, a climate‑controlled testing concept has been designed to reproduce realistic operational temperature and humidity conditions.
For floating substructures, suitable raw materials for low‑carbon geopolymer concrete and circular lightweight aggregates (CLWA) have been identified and tested. Initial formulations demonstrate promising mechanical performance together with a reduced carbon footprint. New circular routes for incorporating recycled glass, including material originating from wind turbine blades, have been developed. In addition, a novel functional coating enabling large‑scale production and enhanced CO2 interaction has been created.
In parallel, the foundations for virtual replicas have been established through the development of constitutive models for geopolymer concrete and the identification of monitoring technologies linking experimental data with numerical simulations. Sustainability assessment activities have also been initiated, including the definition of benchmark technologies and the start of data collection for life‑cycle analyses.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

CIRCWIND goes beyond the state of the art by integrating material innovation with advanced physics‑based and data‑driven modelling approaches that explicitly capture fatigue, damage evolution, and environmental effects.
For wind turbine blades, the project advances multiscale modelling of composite damage under realistic load spectra, enabling improved lifetime prediction and the design of next‑generation damage‑tolerant materials compatible with circularity and recycling strategies.
For floating substructures, CIRCWIND introduces a fully circular, low‑carbon geopolymer concrete concept capable of replacing conventional cement‑based materials while meeting demanding offshore performance requirements.
The integration of virtual replicas represents a further advancement beyond current practice, enabling the coupling of monitoring data with simulation models to assess structural health and remaining useful lifetime. This approach supports predictive maintenance strategies and safe lifetime extension, reducing both costs and environmental impact.
To ensure further uptake and long-term success, key needs include continued validation and demonstration in operational environments, alignment with certification and standardisation frameworks, engagement with industrial supply chains, and access to investment for scaling up manufacturing and recycling solutions. CIRCWIND contributes to these aspects through validation activities, standardisation dialogue, and the development of sustainability‑driven value chains.