Accelerated development of a tidal stream energy industry
Our research has been instrumental to the successful delivery of major objectives of two national industry-academia marine energy projects commissioned by the Energy Technologies Institute (ETI).
Our projects have reduced engineering risks that had been of concern to potential investors. Investor confidence in tidal energy has been demonstrated by Alstom's £65 million acquisition of a turbine developer following key outcomes of the ETI ReDAPT project.
The development of a marine energy industry in the UK, with tidal stream a major component, is forecast to generate more than 68,000 jobs, 20% of electricity supply and an export market valued at more than £70 billion (House of Commons Select Committee, HC1624, 2012). It has been widely recognised (UKERC, DECC, ETI) that investors would only make a significant commitment to tidal stream development after several key engineering advances had been made, including:
- development and validation of engineering models to predict energy yield, and hence revenue, from commercial-scale farms;
- demonstration of deployment and operation of a commercial-scale turbine;
- development and validation of engineering tools to enable system refinement, and hence cost reduction;
- increased understanding of the environmental flows at tidal stream sites pre and post-deployment.
Research conducted in our Department, including development and validation of open-source software for tidal stream system design, is making a key contribution in an emerging UK tidal stream industry.
Our research on tidal stream systems has addressed the development and validation of computational methods for prediction of the power output from arrays (farms) of tidal stream turbines and of the unsteady loading of tidal stream turbines in realistic tidal flows. This builds on research into wave energy arrays, computational fluid dynamics (CFD) methodologies and the physics of shallow water flows. The key outcomes have been to:
- quantify the influence of hydrodynamic interactions on the loading and power output of closely spaced groups of horizontal axis tidal stream rotors;
- develop and validate CFD methods with high-performance computing for prediction of the time-varying loads on a tidal stream turbine subject to turbulent flow representative of full-scale measurements.