Economics-constrained tidal turbine array layout optimisation at the Putuoshan–Hulu island waterway

Abstract

For the successful large scale commercialisation of the tidal stream energy industry it is imperative to consider array revenue rather than simply array power performance. This article reports on the application of a gradient-based optimisation algorithm to establish the optimal array size and layout at the Putuoshan–Hulu Islands waterway. Array economic viability is considered within the optimisation by introducing a break even power concept. Results show that the break even power constraint promotes increased power output per turbine. In response, the overall turbine number decreases due to economics-constraints, leading to an overall reduction in overall array energy yield. Thus, array profit decreases with increments in break even power. A hypothetical practical constraint linking water depth and array cost is also considered, demonstrating an intricate relationship between array design and spatial variability. Finally, using these numerical experiments, we derive development priority maps based on the optimised turbine layouts in order to help guide the tidal stream energy developments in the Putuoshan–Hulu Islands waterway.