Reverse osmosis, the state-of-the-art technology for seawater desalination, is an increasingly common method of desalination, because of its relatively low energy consumption.
The seawater is forced at high pressure (to overcome the osmotic pressure) through a semi-permeable membrane, only allowing certain atoms and molecules through thus separating the water from the dissolved materials such as bacteria, viruses, lime and heavy metals.
The system can be fitted with additional filters according to the kinds of substances present in the water. For higher level of protection against germs, UV irradiation can be installed for additional purification.