Pilot Testing of the Ocean Oasis Wave Power Driven Desalination Plant

Abstract The Ocean Oasis buoy is a floating wave energy converter (WEC) which utilizes the relative motion between a buoy and a disc floating in a central deep moonpool to pressurise seawater and run it through a standard RO process. A combined flow control and energy recovery unit has been developed to ensure that the seawater provided to the RO membranes has a steady flow and pressure and that the remaining energy in the brine is utilized before the brine is discharged. Fresh water is led to shore using inexpensive hoses on the seabed. The buoy is floating freely anchored to the seabed using a conventional catenary mooring system. The moving parts in the power take-off (PTO) system are easily accessible above water, protected in the central part of the buoy above the disc, and designed for easy replacement using small maintenance vessels. In adverse weather conditions the disc is lifted and locked securely to the buoy so that the system behaves as a single buoy unit with no moving parts. After many years of development, analysis and model testing, a full-scale pilot was successfully deployed and tested in Gran Canaria in 2023 and 2024. The present paper describes the development and testing of the pilot, the main observations and learnings from the process, and the way forward towards fully commercial and autonomous fleets of floating desalination plants.