Hydroelectric energy is energy that has been generated by using the force of flowing water and is the most commonly used form of renewable energy. Hydroelectric plants were responsible for producing approximately 20% of the world’s electricity in 2006 and amounted to almost 90% of electricity generated from renewable sources. Hydroelectric plants are highly advantageous as a source of reliable clean energy production as once they are constructed they produce virtually zero direct waste and have far lower carbon dioxide (CO2) emissions than energy plants that are powered by fossil fuels. CO2 is, of course, the principal greenhouse gas that is the primary concern of conventional fuel usage, so lower emissions are directly beneficial to the environment.

The vast majority of hydroelectric power is derived from dammed water that drives a water turbine and generator. The majority of hydroelectric plants supply public electricity grids, although some are built specifically to serve industrial enterprises. Hydropower for use in industrial purposes can actually be seen spanning back hundreds of years, with traditional waterwheels being used to assist with production in agricultural or industrial areas around the world.

Most of the world’s electricity from hydroelectric plants is generated by large hydroelectric generators, although small plants are used in some circumstances. Small plants may also be connected to distribution grids, although they may also supply power solely to single dwellings or isolated communities. Small plants are, naturally, economically and environmentally more favorably and can also be completed much more rapidly. Such small plants are especially popular in China, where more than half of the world’s small hydro capacity is located. Small hydroelectric generators are also showing growing popularity in countries such as the US, however, as many residents living near regular water flow are discovering the relatively inexpensive benefits of utilizing hydroelectric energy for their own personal homes.

Hydroelectric production is advantageous chiefly because it eliminates the costs involved with using fuel, such as the rising cost of fossil fuels, as well as being immune to import costs.

Hydroelectric dams, due to the fact that they do not burn fossil fuels, are not major producing sources of carbon dioxide gas and thereby aid their green credentials. In general, hydroelectric plants also have longer lives in economic terms than fuel-fired plants as well given their nature and the low volume of stress produced by water as compared to other combustion methods. Also, as hydroelectric plants are primarily automated they require very few on-site personnel during regular periods of operation, thus even further increasing their effectiveness.

Hydroelectric dams can also help to control the risk of flooding to places located upstream of them.

On the negative side, some of the largest scale disasters have been due to dam failures, and such construction also provides key targets for sabotage and terrorism. This has led to increased concern and attention on hydroelectric generating damns around the world, with particular focus on the Three Gorges Dam in China, the largest hydroelectric dam in the world that is set to be completed in the near future.

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