United Kingdom Centre for Marine Energy Research: The all UK waters, combined, current and wave test facility.

As marine energy technology continues to move rapidly from laboratory to reality, the first generation of commercial wave and tidal energy converters now feed into electricity networks in the UK and Europe. The UK enjoys some of the world's best marine energy resources and is a world leader in the research, development, demonstration and deployment of wave and tidal energy systems. To increase that lead, we must be able to develop ever more accurate models of these and future systems before entering the sea, if we are to optimise their behaviour and performance under realistic combinations of waves and tidal currents. This demands a combined wave and current test tank. Such a tank will also extend our understanding of the effects of environmental features such as islands and coastlines on wave and tidal energy devices. Conversely, we would also better understand the impacts of these devices on the environment and the tank would have wider applications in optimising maritime and coastal defence. To mimic reality in full, waves and currents in the tank must be able to act in any combination, in any relative direction. The realistic wave and tidal tank (RealWATT) described below will create wave and tidal conditions that represent, at scale, any prospective marine energy or coastal site in the UK. It will be able to model conditions equivalent to years at sea in a few hours and will create normal and extreme conditions reliably and repeatedly. There is no combined test tank in the UK or Europe that can do this.The marine renewable industry is developing rapidly. However, most types of wave energy converters are vulnerable to currents and most tidal current energy converters are vulnerable to waves. Although wave tanks and current flow facilities do exist, there are no facilities which can create the necessary wide spectral wave conditions, in terms of both spatial and frequency parameters, coincident with robust current conditions at laboratory scales necessary to give confidence in the research and developmental testing necessary to support the next generation of marine energy converters. Marine currents are rarely simple or unidirectional and usually have complex variations of velocity texture and gradient. Ocean waves are also multi-directional and their height, period, steepness and spectral content vary in equally complex ways. The design of this new test facility takes this into account.The overarching objective of SuperGen Marine Phase 2 is to understand the device-sea interactions across the range of scales from the laboratory to the open sea, when subject to the combined effects of waves and tidal currents and this has give us considerable insight into the need for this tank. Early device deployments have been at tidal sites which are sheltered from waves and wave sites in which currents were expected to be low. Many of the first generation of full scale wave energy prototypes have experienced operational difficulties due to current effects on moorings, with consequent effects on stability and performance. Even in the absence of tidal currents, wave induced currents in coastal waters can have an influence on behaviour. Tidal developers have avoided sites exposed to large waves. The European Marine Energy Centre (EMEC) tidal test site at the Fall of Warness in Orkney was chosen as it is partly sheltered from wave action as was the Strangford Narrows site in Northern Ireland, where SeaGen is deployed. Many of the most energetic tidal current sites are not, however, so sheltered. The Pentland Firth, which is recognised as one of the most significant sites for long term development, and is now the subject of a Crown Estate licensing round, is exposed to significant Atlantic swell. If the industry is to develop and exploit the most energetic sites, research must continue to understand device behaviour in controllable combined waves and currents at model scale in laboratories.

The direct beneficiaries from this project will be research groups involved in activity supporting the marine renewable sector. The facility will enable the testing of marine renewable systems, at reasonable scales, in highly controlled and repeatable environments. At present model testing is only available at the scales envisaged in facilities with limited performance with respect of wave-current simulation or under field conditions in which repeatability is not possible in any real sense. There will be consequential benefit to developers of wave and tidal current energy systems who will be able to have confidence that concepts have been tested under the most robust conditions available. This is particularly significant considering that 1st generation wave systems have been found to be sensitive to performance degradation by currents and that tidal systems are known to be sensitive to wave influence. Communication and Engagement The capabilities of the new national facility will be widely publicised to the research and developmental community. Users of the facility will be encouraged to publicise their research through traditional means and through direct publicity using media such as websites and press releases. In this way the opportunities available through use of the facility will reach those who could benefit the most. In deed it is anticipated that such publicity will be a condition of use, whilst ensuring that this is compatible with ongoing development of IP by commercial users. This will ensure that benefits of the investment in the facility are appreciated by the secondary beneficiaries, which include: the broader marine development community; the UK economy; the environment. The UK economy: If research conducted in the facility can aid viable growth in the marine renewable sector, then this could act to maintain the vibrancy of the UK energy industry as the petroleum sector decreases. The environment: A developing marine renewable sector will inevitably displace fossil fuel consumption, leading to reduced release of greenhouse gases. The marine development community: Development is and has been close to the limits of understanding of the necessary engineering science principles. Improved testing infrastructure, such as that proposed for the new national facility, will enable research targeted at increasing the knowledge base required to support the development of new technology. Collaboration and Co-production Once the national facility is operational, the research and development community will be invited to participate in a networking programme to identify optimal practice in making the facility available in a self sustaining manner. Exploitation and Application A management board will be established to support the management of the national facility once established and operational. Capacity and Involvement The PI will be responsible for overseeing the design and construction of the facility. He will, however, have to establish a professional working group to manage the project on a day to day basis. Impact Activity Deliverables and Milestones The development of the facility will be monitored: Establishment of internal web communication (commencement of the project) Establishment of external web communication mechanisms (commencement of the project) Press publicity on the purpose of the facility (1 month from project commencement and ongoing as required) Conference presentation on the facility capability (2 within the 24 months from commencement) Journal presentation on facility capabilities (1 within 24 months of commencement)