This paper presents a complete methodology for an integrated simulation of the influence of seabed morphology on the performance of Oscillating Water Column wave energy converters. Different wave characteristics are tested, particularly storm and post-storm conditions. The simulation domain is set in ANSYS Fluent®, where the changes in seabed under different wave conditions are implemented. The turbine is simulated in terms of pressure drop and pneumatic performance by an Actuator Disk Model (ADM). Results show that the efficiency in energy extraction in the OWC is directly influenced by the equilibrium states of the seabed linked to the storm evolution.