Oceanlinx WEC devices have the potential to produce fresh water by generating high pressure sea water and converting it through a Reverse Osmosis (RO) system. The major advantage is that only fresh water would be pumped ashore, while the brine would be easily discharged around the device through local wave action, current and wind and the use of special outlets to allow adequate mixing with sea water.

In typical RO onshore plants, only 1/3 of the total sea water pumped to shore is converted into fresh water, the remaining 2/3 of the volume being pumped back offshore as concentrated brine. As a result, significant energy savings could be achieved by using WEC devices rather than conventional systems.  An additional advantage is that instead of having one massive desalination facility onshore, multiple Oceanlinx arrays can be spread along the coast to provide a fresh water supply tailored to the needs of coastal communities.

Oceanlinx has already completed some preliminary engineering work for its desalination capability and is pursuing this technology development. Efforts to advance the wave based desalination design will now focus on developing efficient solutions to cater for the fluctuating power input, because RO systems requires continuous energy supply to maintain constant pressure and supply of the feed seawater flow.

In principle, the use of an Oceanlinx Mk3 WEC device for desalination, combined with the provision of power from the grid to balance the energy supply during wave down times, could potentially provide 3 million litres of potable water per day (3,000 cubic metres). This will be enough to cover the needs of approximately 3,500 Australian households, under the assumption that a state-of-the-art RO system requires 3.5 kWh to pressurize 1m3 of seawater.

Desalination Process