Hydropower

Hydropower or water power is power derived from the energy of falling or fast-running water, which may be harnessed for useful purposes. Since ancient times, hydropower from many kinds of watermills has been used as a renewable energy source for irrigation and the operation of various mechanical devices, such as gristmills, sawmills, textile mills, trip hammers, dock cranes, domestic lifts, and ore mills.

History

The first recorded use of hydropower was in the form of water wheels, which were used in ancient Greece for grinding wheat into flour. The Romans also made significant advancements in the use of hydropower, using it to power mills and machinery. Water wheels continued to be used throughout the Middle Ages and into the Industrial Revolution, when they were replaced by turbines.

Types of Hydropower

There are three main types of hydropower: Impoundment hydropower, Diversion hydropower, and Pumped storage hydropower. Each type uses a different method to harness the power of water.

Impoundment Hydropower

Impoundment hydropower, the most common type, uses a dam to store water in a reservoir. Water is released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity.

Diversion Hydropower

Diversion, or run-of-river, hydropower, channels a portion of the river through a canal or penstock. It may not require the use of a dam.

Pumped Storage Hydropower

Pumped storage, stores energy by using two water reservoirs at different levels. During periods of low electrical demand, excess generation capacity is used to pump water into the higher reservoir. When there is higher demand, water is released back into the lower reservoir through a turbine.

Environmental Impact

While hydropower is a renewable and often clean source of energy, it can have significant impacts on the environment. These include changes to water quality, disruption of aquatic ecosystems, and impacts on local communities. However, with careful planning and management, many of these impacts can be mitigated.

See Also

• Renewable energy
• Water wheel
• Turbine
• Impoundment hydropower
• Diversion hydropower
• Pumped storage hydropower