Please I need a PhD topic in Wind Turbine renewable energy ? Any aspect of wind turbine where further research is possible either in Offshore or Onshore.
I realize you are most interested in larger machines. However, generating energy closer to where it will be used makes more sense for redundancy, resiliency, and fortifying distribution networks. There needs to be a high-resolution (~10-100m) data (wind speed, direction) collected schema for small wind turbines in high roughness (urban, built) environments.
See NREL's 2016 report, "Deployment of Wind Turbines in the Built Environment: Risks, Lessons, and Recommended Practices". https://www.nrel.gov/docs/fy16osti/65622.pdf, and review the results of the 2008-2009 Warwick Wind Trials (in your part of the world, Midlands of the UK) and the results of the 2009 Zeeland Small Wind Trial. http://www.ingreenious.com/images/ISWC%202009%20090410.pdf
Vibration effects on the longevity of blades made from various materials such as aluminium, carbon composites, etc., and possibly hybrids made by using different materials laminated at different spanwise stations.
I propose the following topic in this matter: Predictive analysis of electricity production from wind turbines in a specific geographical area before deciding whether to build a wind farm. The use of Big Data Analytics and Business Intelligence technologies when conducting the aforementioned predictive analysis.