Abstract
Wave energy is a renewable resource with enormous, untapped potential. Devices known as WABs (Wave-Activated Bodies) constitute the most diverse category of WECs (Wave Energy Converters). This review systematically analyzes the state of the art in WAB technology development, evaluating their Technology Readiness Level (TRL), energy performance, mass-to-power ratio, economic indicators (LCOE and CAPEX), and potential applications, with specific attention to the Mediterranean basin. To focus on technologies with realistic near-term deployment prospects, the analysis is deliberately restricted to devices with a maturity of at least TRL 5 (TRL ≥ 5); on this basis, ten devices spanning four representative subcategories (point absorbers, attenuators, flexible tube devices and gyroscopic systems) were examined. Point absorbers are the most mature and best-represented class: compact resonant converters such as CorPower Ocean C4 have been tested and grid-connected in open ocean conditions, achieving among the most favorable mass-to-power ratios (about 200 t/MW). The Mocean Blue X attenuator and the SBM S3 flexible tube converter illustrate alternative, storm-resilient architectures at intermediate maturity, the latter replacing rigid hulls and conventional power take-offs with an elastomeric tube and distributed electroactive conversion. Gyroscopic systems enclose all moving parts within a sealed hull; among them, ISWEC is the only WAB device grid-connected in the Mediterranean Sea. Across all classes, the mass-to-power ratio emerges as the key driver of economic competitiveness, while integrated WEC–PTO–control co-design is the main lever for reducing the LCOE. Device-level cost data are rarely disclosed at pre-commercial stages, so the comparison is reported as an evidence-bounded ranking that distinguishes demonstrated performance from undisclosed information, together with the most realistic routes toward bankable Mediterranean wave farms.