Optimising Structural Loading and Power Production for Floating Wave Energy Converters
Reason for embargo
Under embargo until the end of the conference
This paper investigates the design trade-off between power production and structural loading for Wave Energy Converters (WECs), based on tank test results for the Albatern 12S floating wave energy array. This work feeds into the design development process, which is currently in the concept design and testing phase. The paper focuses on two methods for reducing structural loading: limiting the power take off (PTO) torque generation capacity (for operational loads), and controlling the PTO damping (for extreme loads). The torque that can be generated by the primary PTO mechanism affects the size (and cost) of the structural components within the device. Increased torque results in a potentially greater power capture, but also greater structural loading. It is therefore important to highlight the target torque limit early in the design process. The aim of this work is to identify the optimum torque limit to refine the design towards the lowest overall Levelised Cost of Energy (LCoE). In addition, a high-level investigation of the impact of PTO damping on extreme loading has been carried out, to help to identify appropriate “operational” and “survival” sea states for the device. The paper calculates an optimum torque limit for the device at the West Harris site and quantifies the trade-off between Annual Energy Production and structural cost, using the LCoE as an optimisation criteria. The approach is in principle applicable to other technologies, if the design drivers are adjusted to the technology’s working principle.
Tank testing was funded by Wave Energy Scotland (WES) as part of the Novel Wave Energy Converter Stage 1 (NWEC1) programme. This work has been carried out as part of the IDCORE programme, funded by the Energy Technology Institute and RCUK Energy programme (grant no. EP/J500847/1)
This is the author accepted manuscript. The final version is available from EWTEC via the link in this record.
EWTEC 2017: 12th European Wave and Tidal Energy Conference, 27 August - 1 September 2017, Cork, Ireland
Place of publication