Nowadays, atmospheric pollution and climate change have encouraged Governments to invest in renewable technologies for clean energy production. Wave Power constitutes an interesting option in the panorama of renewables and starting from the first results achieved in the '70s, in the last and present decade the major efforts have been concentrated to make Wave Energy Converters (WECs) more profitable and predictable. The research activities described in this work concern the development of a pendulum converter (PeWEC: Pendulum Wave Energy Converter), designed for the Mediterranean Sea scenario. In the first part of the paper, the mathematical model describing the floater and pendulum dynamics is presented. The equations previously described are then used to implement a model-based design and optimization methodology. The latter is constituted by three different tools connected in cascade and characterized by an increasing degree of complexity and fidelity. The combination of these tools, together with the evaluation of the plant Levelized Cost of Energy (LCOE), allow to determine an optimal device configuration for the installation site chosen. The methodology is here used to design a preliminary layout of the full-scale PeWEC device, considering the Pantelleria Island (Italy) wave climate as reference.