Large marine structures characterized by hydroelasticity are common in ocean space utilization, such as offshore floating cities, floating energy islands, floating breakwaters, and others. These structures typically have one or two dimensions significantly larger than the others (e.g., draft). Hence the hydroelastic deformations under wave action is important for such structures (Heller and Abramson in J Am Soc Naval Eng 71:205–209, 1959 [14]). Efficient modeling that simultaneously accounts for hydroelastic effects and the complex connection characteristics between offshore renewables and Very Large Floating Structures (VLFS) serves as a key tool for designing such novel integrated systems. To this end, in this chapter, we present a numerical investigation into the hydrodynamic performance of VLFS coupled with a wave energy device array, along with the developed numerical framework.