Hydro power is most often defined as the conversion of energy from moving water, but what are the pros and cons of using hydro power as a sustainable source of energy. First the basics of hydro power must be understood, hydro power relies on the water cycle and the amount of water that runs through a river or stream determines the amount of water available for producing hydro power. Since hydro power relies on water hydroelectric plants are located next to water source, and the volume of water as well as the change in elevation are what determine the amount of energy that the water possesses.
Examples of high energy water sources include Niagara Falls and the Columbia River. Both the Columbia River and Niagara Falls utilize a a pen stock which allows to water to flow through and turns a blade in a turbine to produce electricity.
The history of hydro power goes back thousands of years where it was conventionally used for mechanical milling , or grinding grain. However the first industrial use of hydro power to generate electricity occurred in 1880 in the United States. Currently hydro power accounts for “around 7% of total U.S. utility-scale electricity generation and 41% of total utility-scale electricity generation from renewable energy sources”. (eia.gov)
Hydro power is considered one of the front runners for renewable energy, however at times hydro power does have unintended consequences on the environments that it is placed in. While hydro power generators do not directly emit pollutants into the atmosphere the construction and operation of the generators do. The manufacture of steel and concrete that hydro power dams need produce high amounts of fossil fuel emissions. Also greenhouse gases such as carbon dioxide could possibly form within the dams during operation. Additionally hydro power dams inhibit fish migration, and can change the temperature of a body of water. These changes have a major impact on the native species of an ecosystem near a hydro power dam. So while hydro power is a viable source of renewable energy unintended consequences can arise from it’s implementation.
Another form of hydro power is tidal power which uses the power of tides to generate energy. However tidal power is only efficient when there is a tidal range of 10 feet. A disadvantage of tidal power is that the generators can increase the turbidity of estuaries resulting in a negative impact on animals and plants. Lastly wave power is another subgroup of hydro power. Although still in the developmental phase, wave energy is projected to be able to produce 2.64 trillion kilowatthours of energy.