A team of design engineers from the University of Edinburgh has developed and manufactured a state-of-the-art turbine blade that they say could significantly reduce the coast of tidal energy.
The design of the blade, which was the first to be built in Scotland, reduces the amount of materials necessary, bringing down the weight, volume and, crucially, the cost of manufacture.
The team is based at FastBlade – the world’s first rapid-testing facility for tidal-turbine blades – at Rosyth in Fife, Scotland. The project began in October 2022.
‘This project represents a major step change in our group’s capacity to manufacture tidal blades at reasonable size scale (around three metres long) at a reasonable speed,’ said FastBlade leader Eddie McCarthy of the University of Edinburgh’s School of Engineering. ‘We have found a faster, cheaper route to manufacture than the usual tidal-blade fabrication process, based on an altered design. We hope the combination of improved design and optimised manufacturing process will contribute to reducing the levelised cost of energy (LCOE) of tidal-stream energy, with the long term goal of matching the LCOE of offshore wind.’
Currently, the UK contract price for tidal-stream energy is around £178 per MWh, compared to £65 for offshore wind. The high generation cost is a barrier to the development of tidal energy – potentially the missing piece of a year-round, renewable energy grid.
‘This is the first time this type of structure has been used in blade manufacturing. Its monolithic structure eliminates the weaker adhesive joints found in conventional rotor blades, which will make it more resilient to tidal-stream conditions, said lead design engineer Professor Dilum Fernando.
The blade was manufactured with Tocardo Turbines for tidal-energy technology company QED Naval as part of the European Tidal Stream Industry Energiser Project, known as TIGER, in a service agreement brokered by Edinburgh Innovations, the University of Edinburgh’s commercialisation service.
‘We are delighted to be working with the University of Edinburgh on this next generation of tidal turbine blades, which will help bring down the cost of tidal installations, said Jeremy Smith, managing director of QED Naval. ‘We have deliberately demonstrated the design tools, processes and build method on our smaller T1 blade design, using a 6.3-metre rotor diameter, but we will be pulling these through into our T3 blades up to 14-metre rotor diameter. This work, and its part in the EU Interreg TIGER Project, helps showcase cost savings and the benefits of tidal energy.’
The four completed blades have been deployed in QED’s Subhub tidal platform, currently undergoing sea trials in Langstone Harbour on the south coast of England. The University of Edinburgh team is looking for funding to carry out detailed testing of a fifth blade at FastBlade.
‘A recent report found that tidal-stream energy could provide more than 6GW of energy to the UK grid by 2050, providing a significant baseline power source for our future electricity grid,’ said Ian Hatch, head of business development for the College of Science and Engineering at Edinburgh Innovations. ‘This project showcases one of the many benefits of using the state-of-the-art equipment that is available for commercial companies to access at the university.’
‘A team of 13 worked on this project, providing researchers and students with real exposure to tidal-blade manufacturing and developing rare skills in this important area for the Scottish and UK economy, as well as for the future of global sustainable energy,’ McCarthy added. ‘It is an example of the leading role FastBlade is taking in bringing together researchers, practitioners and students to deliver high-impact projects to make tidal-stream energy a reality.’