A new desalination method uses wave-powered technology

The new method addresses the reliance of desalination systems on the main electricity grid

97% of Earth’s water is found in the sea and contains salt. As the world faces increasing water scarcity, desalination has long been touted as a way to derive vital fresh water from the world’s oceans. But existing reverse-osmosis technology requires a connection to the main electricity grid. Procuring energy in this way is expensive, and creates additional demand for fossil-fuel-derived energy. Moreover, this option is not available for more inaccessible regions that are among the most exposed to water scarcity.

There is therefore a need to develop desalination systems that capture energy from green sources separate from the main electricity grid. In response to this challenge, participants in the EU-funded H2020 W2O project have invented a method to desalinate water through wave-powered technology, proving that a system run on renewable and off-the-grid energy is possible. The new system—called Wave₂O^TM—uses a Wave Energy Converter (WEC) placed on the seafloor. This sways with the motion of the waves, providing a source of free energy.

In the words of Olivier Ceberio, Chief Operating Officer of Irish company Resolute Marine, who co-ordinated the project, “This technology delivers free energy from a consistent and inexhaustible renewable energy source: ocean waves.” 

A further benefit of the Wave₂O system is that it can be installed swiftly and operated completely off-grid, processing large volumes of fresh water relatively inexpensively.

Following the initial project, Resolute Marine is now focusing its efforts on developing projects in Cape Verde. In a recent interview for a report produced by the International Energy Agency and Ocean Energy Systems, CEO Bill Staby explained that scarcity is particularly acute in this island nation. 85% of the country’s water comes from dirty and noisy diesel-powered desalination plants, while water shortages create stressful living conditions for the population.

At Springwise we have seen several innovations concerned with desalination, such as a desalination pump inspired by the mangrove. We have also seen prior examples of desalination systems that utilise renewable energy sources, such as solar power.