Fresh water is one of the most important resources that preserve life on this planet. Unfortunately, it only comprises about 2.5 percent of all the waters on Earth, with 69 percent still locked up in glaciers. Should there be a technology that would allow man to utilize that locked up water to add to the current supply, it could be too late as global warming would have melted the ice into the salty ocean.
A more serious issue with fresh water that is already being experienced in many places around the world is the drying up of rivers, lakes, and groundwater. Water shortage can spawn terrible problems, including drought and famine. Supply of fresh water must be continuous for life to keep flourishing.
One effective solution to water shortage is seawater desalination. This is the process of filtering out salt in seawater to produce fresh water. Although the concept may seem simple, it involves a complex process since the task requires filtration in the molecular level. The principle most useful for this process is reverse osmosis.
Osmosis is the movement of pure water through a semipermeable membrane into an area containing liquid with solute due to naturally occurring osmotic pressure. If pressure greater than the osmotic pressure is applied in the liquid with solute, the process can be reversed, allowing the solute to be filtered out. In the case of salt water and pure water, pressure will be applied on salt water to filter out its salt content.