The term "hydropower" is a common word used to generalize the many different means of utilizing the energy in flowing water, ranging from large hydroelectric power plants to systems that harness both tidal and wave power. Hydroelectric facilities provide approximately 25 percent of the world's electricity supply-with plants operating in 86 countries across the globe (Carless, Jennifer 1993). Hydroelectric dams produce electricity much more efficiently than other conventional sources (such as coal and nuclear) while also maintaining a lower price-per-kilowatt (Carless, Jennifer 1993). Finally, hydro systems are "clean", meaning they release no hazardous by-products into the environment.
             Hydropower is indirectly associated to solar energy, due to the fact that the sun evaporates water from the earth (Carless, Jennifer 1993). The evaporated water then returns to earth in the form of rain, sleet, snow, etc., filling waterways that eventually make their way into the oceans (Allaby, Ian 1990). The flow of the water in these streams and rivers is what conventional hydroelectric systems use for power generation.
             The logic behind hydroelectric power is quite elementary: it simply uses the natural kinetic energy of falling water. "Falling water, which has been stored behind a dam or else flows naturally along a river, passes through a turbine, which turns a generator and produces electricity" (more on this subject later) (Carless, Jennifer 1993 p.57). Mechanical energy can also be produced by falling water, using the energy to spin a water wheel, which in turn grinds grain in a mill (Carless, Jennifer 1993).
             Hydroelectric systems are the oldest (and considered the most reliable) type of electric generation in service today (Carless, Jennifer 1993). The major drawback of this form of generation is the adverse effect a drought has on the electrical output. An example of this is the drought during the summer of 1988, which caused a ...