New climate change minister Amber Rudd MP found out first-hand about the UK’s leading role in ocean energy research and development when she officially opened the FloWave Ocean Energy Research Facility, a world-unique facility for testing and de-risking marine energy technologies and projects.
FloWave is a 100 per cent owned subsidiary company of the University of Edinburgh, and is located in a dedicated building on the western edge of the University’s King’s Buildings campus in Edinburgh.
Conceived for cutting edge academic research into wave and tidal current interactions, FloWave is also an amazing tool for commercial developers to ensure their technologies and projects perform ‘right first time’ and are de-risked as much as practical before cutting steel or going offshore.
The facility will work closely with the Institute for Energy Systems, one of five multi-disciplinary research institutes within the University of Edinburgh’s School of Engineering, with the goal of increasing the Institute’s internationally recognised expertise in marine energy device testing, evaluation and array deployment.
For new device developers FloWave represents a great asset for de-risking and refining performance of new designs at model scale before cutting steel on a first prototype. For more established device developers – meaning those with prototypes already in the water on test at EMEC and elsewhere – FloWave is an opportunity to run model-scale tests on revised designs that incorporate the ‘lessons-learned’ from actually having a device in the water.
For demonstrator project and commercial array developers FloWave presents a world-unique opportunity to validate CFD layout, micro-siting and energy yield predictions with physical modelling – before investing tens of millions in the project itself.
The Tank and Equipment
The heart of FloWave is a 30m circular concrete basin containing the 25m diameter wave and current tank.
The 5m deep tank contains 2.4 million litres of fresh water and is circumferentially ringed by 168 absorbing wave makers. Additionally, twenty-eight submerged flow-drive units can simultaneously and independently drive current across the tank in any relative direction, with maximum current velocities of 1.6 metres per second.
A rising tank floor and 5t overhead crane enable quick and easy installation of individual devices, or arrays of wave or tidal current generators.
Circular Tank Benefits
Because the tank is circular and therefore non-directional, waves and currents in the tank can act in any combination and in any relative direction across the large central volume 17 metres in diameter and 2m deep.
Optimised for 700mm, two second waves, the 168 absorbing wave-makers paddles can create full-spectrum multi-directional waves as well as more traditional monochromatic waves, and all this over a roughly circular test area of more than 200 square metres. Depending on the scale chosen this corresponds to full-scale seas of up to 28m waves, currents in excess of 12 knots, and a sea-area of approximately 2 square kilometres.
360 degree symmetry of wave and current conditions
Because the tank is circular and therefore non-directional, waves and currents in the tank can act in any combination and in any relative direction across the large central volume.
1/20th scale model testing conditions
Bridging the gap between 1/100th ‘flume scale’ test modelling and testing prototypes at 1/6th scale and above in the real sea, testing at 1/20th scale at FloWave introduces a critical evaluation stage-gate into the device development cycle at the “go/No-go” decision point for investors and funders. This helps to bridge the so-called ‘valley of death’ between small-scale test equipment and full scale prototypes.
Unrivalled control and repeatability
Test conditions for current and waves in all directions can be simply programmed and run, or chosen from a suite of standard ocean spectra correlating to actual measured sea-states. Complex wave and current conditions for normal, challenging and extreme conditions can easily be simulated and repeated time after time, thereby allowing devices and control algorithms to be be iteratively adjusted to find optimal performance settings and reducing the time taken to get to the optimised ‘right first time’ design.
Perfect for Array Project Testing
Building on the techniques developed for the 100th scale curved wave tank at the University of Edinburgh over the last twelve years, FloWave’s 220 square metre test area is large enough to accommodate small arrays of devices, and will be of particular interest to Project developers looking to physically validate computational layout models.
ST Staff Writers
This post was prepared by Solar Thermal Magazine staff.