- Man-made dams can be used to produce hydroelectic power.hydroelectric dam image by Jim Parkin from Fotolia.com
Hydroelectric power is the use of water to create energy. In essence, it captures the earth's gravitational force by using gravity-pulled water to turn generator turbines. Typically, the water from large rivers or waterfalls is used, but large man-made dams can produce the water flow necessary for power. The more water flow and volume, the more electricity produced. - Hydro power has been used for millennia, with waterwheels being used to grind wheat since the time of the ancient Greeks. In 1878, it was used for home electric lighting for the first time, with Cragside House of Northumberland, England being the first house lit by hydroelectricity. Soon after, in 1879, the first hydroelectric power plant was built in Niagara Falls and started powering the city of Niagara Falls' lamp posts by 1881. Today, almost one fifth of the entire world's energy is derived from Hydro power.
- With a steady source of flowing water, such as the Niagara Falls, hydroelectric power is a renewable source of energy, meaning its source of power will never run out. This is because water systems are naturally replenished by rainfall, which in turn comes from sea and fresh water evaporated by the sun. Because hydroelectric power does not need fuel, it is unaffected by global factors such as oil costs, and causes little to no pollution. Also, since the earth's gravity is constant, Hydroelectricity can be constantly generated, and plants can reach full output quickly. Also, because the flow of water is generally predictable, hydroelectric power plants are often highly automated, with low labor demands. Furthermore, without the destructive nature of power-producing fuels, hydroelectric plants are more durable than most other power plants, and some have lasted up to 50 or 100 years.
- Power plants must be built next to a source of water, and finding a suitable site is often difficult. Even if a suitable site is found, hydroelectric projects can adversely affect neighboring ecosystems. Power plants can often change the environments of rivers downstream, and man-made dams can reduce fish populations. Also, building a dam has a high initial cost, though some of this cost can be shared by other industries since dams have uses outside of hydroelectricity, such as irrigation and flood control.
