Using solar energy to purify polluted or salt water

With rapid increase in population, global warming and a loss of fresh water, there will soon be no free fresh water in the world. Soda manufacturers are quickly buying the water resources all over the world in order to dominate and control  the water market. Water purification using the solar energy can be the answer to our future needs. 
 Project description:
In this project you will design a water purification system that can produce fresh water using sea water or polluted water. You will then measure the production rate of your water purifier and perform some calculations to find out what size water purifier can produce enough water for one person, entire family or a small town.
 Details of this project:
More details or support for this project is available for the members of web site. Material needed for experiment or a science kit about this title may be available at