Dr Richard Willden, Dr Takafumi Nishino and Prof Guy Houlsby of the Oxford Martin School’s Programme on Globalising Tidal Power Generation organised the first Oxford Tidal Energy Workshop on the 29th and 30th March 2012. Here, they tell us about their discussions, and why tidal energy research is urgently needed to help address a potential crisis in our global energy supply.
It is thought that tidal-stream energy could deliver a significant amount of renewable power at many locations across the globe, but fundamental understanding of the nature of the resource is necessary to make widespread efficient energy extraction possible. The UK's particularly high share in the global resource has encouraged a number of tidal energy research groups in the UK to take on this challenging research.
While these research groups meet at relevant international conferences, the need for, and common interest in, more regular, less formal meetings was the motivation for holding our March workshop. We brought together around 40 people, including senior pioneering researchers in the field, academics and PhD students to engage in two days of animated technical discussions about the future of tidal energy and associated policy implications.
Our work at the Programme on Globalising Tidal Power Generation has identified the need for a multi-scale approach to the tidal energy resource. The workshop included presentations that explored a range of issues to advance tidal energy research:
- novel experimental, computational and theoretical approaches to evaluate potential device designs,
- device-device interaction (array scale) modelling to achieve power enhancement through inter-device interactions, and
- basin scale modelling and large scale field measurements.
Compared to wind energy, in the immature field of tidal-stream energy there is still no consensus on the optimal device design. Recent experimental results from three very different designs were presented at the workshop. Similarly, different approaches of varying complexity and computational expense are currently being applied to device and array scale modelling to better understand the hydrodynamics of tidal-stream turbines and to evaluate the potential performance of tidal turbine arrays. Advances in basin scale modelling are essential to provide increasingly accurate estimates of the size of the global tidal energy resource. Recent detailed measurements of flow conditions and bathymetry (the study of underwater depth of ocean floors) at potential tidal-stream turbine sites in the UK are providing new data, which can be used to validate basin scale models.
Workshops like this are a vital component for advancing research in tidal energy. We need open, constructive discussion that enables the communication of ideas among various avenues of research. The opportunity to promote collaboration, especially between experimentalists and modellers, was also highly valuable.
Our current research in the Programme for Globalising Tidal Power Generation is already yielding results in the areas of novel turbine assessment and tidal array dynamics. To advance progress, we continue to seek new collaborative opportunities and work with a range of academics, experts and policymakers to ensure any strategies to address energy needs through tidal energy are based on the best academic research and practical evidence.