Layout optimisation of 1st-generation tidal energy arrays

Early tidal energy arrays are now in the planning and consenting stage. There is pressure on these projects to deliver successful results and prove the technology can succeed in bridging the gap between single devices currently in sea trials and large scale commercial arrays. A key issue in these early arrays is the understanding of interaction effects between devices, developing awareness of how to reduce the impact of these is similarly crucial. This paper describes a set of scale experiments designed to investigate the optimum spacing of devices within an offset dual-row tidal energy array. It builds on previous work, investigating in further detail the optimization of a single row 1st-generation array and the nature of the flow between devices within an array. It then presents discussion on the effects of installation of a second downstream row with motivation to increase the overall output of the array whilst minimizing negative effects.It is shown that significant additional power may be generated from groups of turbines when spaced optimally in distinct array formations. Discussion focuses on the need for successful array developers to plan array geometry fully before installation; otherwise sub-optimal or even negative performance may be encountered