A group at Stanford university have developed a way to use water to create electricity without using large hydroelectric dams. By taking salt water and freshwater, electricity can be generated in these batteries by taking advantage of thee difference in salinity between the two kinds of water. The battery would be self recharging and would supply extra power it is constantly fuel with water. The way it works is in fact the same way a regular battery works but it uses water. With this technology, every river in the world could become a power plant and it would not require as much space or as many recourses as a hydro electric dam.