One of the common ways to capture wave energy, is via a point-absorber which harvests energy from the up and down movement of waves.
Australia's RMIT has designed a point-absorber with a novel counter-rotating dual turbine. The design can apparently deliver twice the efficiency of other currently available point-absorber wave technologies.
https://www.rmit.edu.au/news/all-news/2021/aug/wave-energy-technology