AI-assisted grading of end-of-life wind turbine composite materials for a circular economy

Project Description:

This PhD scholarship is offered by the EPSRC CDT in Offshore Wind Energy Sustainability and Resilience; a partnership between the Universities of Durham, Hull, Loughborough and Sheffield.  The successful applicant will undertake six-month of training with the rest of the CDT cohort at the University of Hull before continuing their PhD research at the University of Sheffield.

End-of-life blade waste is a pressing issue for the wind energy industry, both for existing blades and future blades. The vast majority of existing blades cannot be recycled and are currently destined for low-value, high-emission end-of-life routes (e.g., incineration or grinding for filler in cement).

The value of these robust composite materials can be retained via reuse in structural applications. For example, it has shown that existing blade materials have sufficient properties and dimensional tolerances to be segmented and used as basic construction elements. Thermoplastic composites blades, likely the blades of the future, have additional potential in that they can be thermoformed into new geometries, while also ‘healing’ the thermoplastic matrix. The challenge of reuse is that blade materials vary based on several factors including microstructure, macrostructure, and loading history.

This project directly aligns with the CDT’s aim to achieve a sustainable wind farm lifecycle by developing methods for high-value reuse of composite turbine blades. Machine learning and non-destructive evaluation techniques will be developed to efficiently grade the end-of-life material properties. These techniques are already in development at the University of Sheffield for assessing in operando material properties of offshore wind turbine blades. Successful re-development for end-of-life composites could enable reuse in other structural applications.

This PhD will investigate the development of hierarchical Bayesian algorithms to capture the variability of end-of-life composite materials. These algorithms will be combined with destructive and non-destructive test data, and then be used to develop predictive capabilities for grading. This work will establish a foundation for future automated grading systems, which will provide a cost-competitive solution for both the offshore wind energy sector and the wider composites industry. 

Training and development

You will benefit from a taught programme, giving you a broad understanding of the breadth and depth of current and emerging offshore wind sector needs. This begins with an intensive six-month programme at the University of Hull for the new student intake, drawing on the expertise and facilities of all four academic partners. It is supplemented by Continuing Professional Development (CPD), which is embedded throughout your 4-year research scholarship.

You will receive in-house training in statistical methods, composite manufacturing and machining, and mechanical testing, including various methods of destructive and non-destructive evaluation. Industrial visits will act as an additional sources of training in the current state-of-the-art in the project area.

Entry requirements

If you have received a First-class Honours degree, or a 2:1 Honours degree and a Masters, or a Distinction at Masters level with any undergraduate degree (or the international equivalents) in Computer Science, Engineering, Physics, or Mathematics and Statistics, we would like to hear from you.

If your first language is not English, or you require Tier 4 student visa to study, you will be required to provide evidence of your English language proficiency level that meets the requirements of the Aura CDT’s academic partners. This course requires academic IELTS 7.0 overall, with no less than 6.0 in each skill.

If you have any queries about this project, please contact Dr James Maguire j.maguire@sheffield.ac.uk

You may also address queries about the CDT to auracdt@hull.ac.uk.

Watch our short video to hear from Aura CDT students, academics and industry partners:

Funding

The Offshore Wind CDT is funded by the EPSRC, allowing us to provide scholarships that cover fees plus a stipend set at the UKRI nationally agreed rates. These are currently £20,780 per annum at 2025/26 rates and will increase in line with the EPSRC guidelines for the subsequent years (subject to progress).

Eligibility

Research Council funding for postgraduate research has residence requirements. Our CDT scholarships are available to Home (UK) Students. To be considered a Home student, and therefore eligible for a full award, a student must have no restrictions on how long they can stay in the UK and have been ordinarily resident in the UK for at least 3 years prior to the start of the scholarship (with some further constraint regarding residence for education). For full eligibility information, please refer to the EPSRC website.

We also allocate a number of scholarships for International Students per cohort.

Guaranteed Interview Scheme

The CDT is committed to generating a diverse and inclusive training programme and is looking to attract applicants from all backgrounds. We offer a Guaranteed Interview Scheme for home fee status candidates who identify as Black or Black mixed or Asian or Asian mixed if they meet the programme entry requirements. This positive action is to support recruitment of these under-represented ethnic groups to our programme and is an opt in process.

Find out more

How to apply

Applications for this project will open in Autumn 2025 for September 2026 entry.

Interviews will be held online with an interview panel comprising of project supervisory team members from the host university where the project is based.  Where the project involves external supervisors from university partners or industry sponsors then representatives from these partners may form part of the interview panel and your supplementary application form will be shared with them (with the guaranteed interview scheme section removed).

If you have any queries about this project, please contact Dr James Maguire j.maguire@sheffield.ac.uk

You may also address queries about the CDT to auracdt@hull.ac.uk.

References & further reading

[1] Jelle Joustra, Bas Flipsen, Ruud Balkenende, Structural reuse of wind turbine blades through segmentation, Composites Part C: Open Access, 2021, 5, 100137, DOI: https://doi.org/10.1016/j.jcomc.2021.100137

[2] Marcus Haywood-Alexander, Nikolaos Dervilis, Keith Worden, Robin S. Mills, Purim Ladpli, Timothy J. Rogers, A Bayesian Method for Material Identification of Composite Plates via Dispersion Curves, Sensors, 2023, 23(185), p1-22, DOI: https://doi.org/10.3390/s23010185

[3] Angela J. Nagle, Gerard Mullally, Paul G. Leahy, Niall P. Dunphy, Life cycle assessment of the use of decommissioned wind blades in second life applications, Journal of Environmental Management, 2022, 302, 113994, DOI: https://doi.org/10.1016/j.jenvman.2021.113994

[4] Fanran Meng, Jennifer L. Hawkin, Lukas Gast, Stella Job, Conchúr Ó Brádaigh, et al., End-of-life management for wind turbines, Nature Reviews Clean Technology, 2025, DOI: https://doi.org/10.1038/s44359-025-00097-3