A Canadian startup – Oneka – has found a method to operate a floating desalination system based solely on the movement of ocean waves.
Currently there are two techniques used to desalinate seawater: thermal and membrane methods. During thermal desalination, seawater is heated until it evaporates, leaving behind salt. This process is often very energy intensive.
Membrane-based systems, also known as reverse osmosis, work by forcing seawater through a semi-permeable membrane to trap salt. This requires a significant amount of energy, but less than the thermal method.
In both cases, the energy supply usually does not come from renewable or nuclear sources, thus producing CO2.
Meanwhile, Oneka’s floating desalination machine – a buoy anchored on the seabed – uses a membrane system that operates entirely thanks to wave movement. The buoys absorb energy from passing ocean waves and convert it into a mechanical pump that draws in seawater and pushes about a quarter of it through the desalination system. The water is then pumped to land via pipes, again using only the energy provided by the waves.
This technology does not use electricity and is controlled by 100% mechanical techniques. These devices only need a 1 meter high wave to operate. The desalination machine comes in three sizes, the largest is 8m long, 5m wide and can produce up to 49,000 liters of fresh water per day.
According to Moitruongvadothi.vn