Rough ocean with waves crashing into the rocks.
A new research project will address the key challenges that are currently preventing the tidal energy sector from reaching its full potential. Image credit: Shutterstock.

Oxford University to lead tidal energy project for carbon emission reduction and energy security

The University of Oxford is to lead an ambitious £7 million project to help deliver scalable, affordable and sustainable tidal stream energy. Besides boosting energy security, this could help enable tidal stream energy make a meaningful contribution to achieving UK Net Zero goals.

CoTide will deliver the understanding, tools, and data to support the progressive and step change reductions in cost and uncertainty needed to deliver scalable, sustainable, and affordable tidal stream energy. The project will also further develop deep collaborative academic-industry partnerships that will help support and deliver future tidal energy technologies and wider research.

Professor Richard Willden, Department of Engineering Science

‘Co-design to deliver Scalable Tidal Stream Energy’ (CoTide) will bring together three multi-disciplinary teams from the universities of Oxford, Edinburgh, and Strathclyde. Backed by investment from the Engineering and Physical Sciences Research Council (EPSRC), the project will address the key challenges that are currently preventing the tidal energy sector from reaching its full potential.

Project lead Professor Richard Willden, from the University of Oxford’s Department of Engineering Science, said: ‘We have a huge opportunity as a country to harness the powerful tides that surround us and use innovative engineering to develop greater energy security and solutions to help meet our 2050 net zero goals.’

‘This EPSRC investment in CoTide allows us to bring together world-class engineering expertise and drive forward the kind of creative, collaborative research that will ensure the UK remains a world-leader in tidal stream development and deployment.’

Achieving the UK’s target to reach net zero by 2050 requires the decarbonisation of our energy supplies and a huge expansion of renewable energy generation from the current 50GW to 120-300GW. The powerful tides that surround the UK remain underutilised, but have significant potential as a source of greener power that could make a meaningful contribution to this goal. Unlike the wind and the sun, tides ebb and flow at predictable times each day, and so have the advantage that they can provide power that is both renewable and reliable, enabling more resilient energy networks.

CoTide will focus on developing state-of-the-art tidal stream turbine systems. Unlike more traditional tidal barrages and tidal lagoons that require turbines to be installed in structures such as dams or sea walls, tidal stream turbines are fixed directly out at sea in the line of the strongest, most suitable tidal flows. This makes them cheaper to build and install, and reduces their environmental impact.

An artistic image of tidal turbines hanging downwards into the water, suspended from floats. A potential design for future scalable tidal stream energy systems. Credit: Zilic de Arcos, DPhil thesis, 2021.

If fully developed across the UK, tidal stream systems have the potential to generate in excess of 6GW, enough to power over 5 million homes, with an export market worth £25bn supporting over 25,000 marine energy jobs.

But technical challenges remain, and tidal stream systems require careful design to maximise power whilst providing reliability in hostile marine environments characterised by corrosive seawater and unsteady loading caused by waves and turbulence.

To tackle this, CoTide will bring together three multi-disciplinary teams, each with deep world-leading expertise across all relevant areas, including device hydrodynamics, rotor materials, corrosion, risk and reliability, environmental modelling, and system control and optimisation. Together, the researchers will integrate these constituent elements into holistic design processes that will significantly reduce costs by removing unnecessary redundancy and improving engineering solutions and processes.

An indoor wave tank in operation, generating waves across the surface of the water. The University of Oxford’s combined current and wave flume for ocean engineering research. Credit: Richard Willden.
Professor Willden added: ‘Through a unified co-design approach, CoTide will develop a framework to assess the impact of design decisions and will contribute fundamental understanding of how to achieve through-life reliability in addition to maximising the potential of digitalisation for optimal performance.’

The project will also have a strong focus on increasing the sustainability of tidal stream systems. For instance, the team will explore new methods to assess the environmental and ecological impacts of future tidal stream farms, and whether turbine blades could be manufactured from bio-based materials that can degrade at the end of their life.

CoTide will build on the Oxford team’s unique experience and capabilities in designing and testing high-performance turbines, which have been developed through Professor Willden’s EPSRC Advanced Fellowship. In particular, the project will capitalise on Oxford’s recent investment in a state-of-the-art current and wave flume that will allow turbine and platform designs to be rapidly tested under harsh environmental conditions.

Dr Kedar Pandya, EPSRC’s Executive Director for Cross-Council Programmes said: ‘We are proud to be supporting this innovative group of researchers and their push to better develop the UK’s access to clean, green, secure – and reliable – energy. The UK leads tidal stream technology and science development, with most developers based or operating in the UK, and CoTide is a significant opportunity to secure global industry and academic leadership.’

The researchers will work with a group of over twenty industry stakeholders and regulatory bodies including EDF Energy Plc, the Health and Safety Executive, the Marine Energy Council, and global manufacturer Arkema International. This will ensure that CoTide's outputs will deliver new tools, models, and processes that achieve direct industrial impact.

Sue Barr, Chair of the Marine Energy Council, said: ‘In order for tidal stream energy to become more competitive, we need real step changes in system performance, reliability metrics and scalability of the technology, which will require integrated tools which can be utilised by the sector… (The CoTide project’s) collaborative and innovative scope provides a real opportunity for successful outcomes.’

 Further information can be found on the CoTide website.