Impact of wave interactions effects on energy absorption in large arrays of wave energy converters

This paper presents a parametric study on arrays of wave energy converters (WECs). Its goal is to assess the influence of interactions between bodies on the overall yearly energy production of the array. Generic WECs (heaving cylinder and surging barge) are considered. Nine to twenty-five WECs are installed along regular square and triangular grids; the influence of the separating distance between the WECs is investigated. Results show that constructive and destructive interactions compensate each other over the considered range of wave periods. The influence of the separating distance can be limited, especially if the damping of the power take-off is tuned properly, and if the WECs have a large bandwidth. It is found that grouping the devices into arrays have generally a constructive effect. Diffracted and radiated waves in the array lead to a sufficient increase in the energy absorption which overcomes the reduction due to masking effects.

► We study the influence of separating distances between wave energy converters grouped into an array.
► The main indicator is the annually averaged power output of the array.
► A boundary element method hydrodynamic software is used.
► Two kinds of wave energy converters are studied, each having two different control strategies.
► Results show that an optimal layout can be found, resulting of a balance between constructive and destructive wave effects.