how hydropower is generated

Hydropower is electricity generated using the energy of moving water. Rain or melted snow, usually originating in hills and mountains, create streams and rivers that eventually run to the ocean. The energy of that moving water can be substantial.

A typical hydro plant is a system with three parts: a generation plant where the electricity is produced, a dam or canal that can control water flow, and either a river or reservoir to supply the water. To generate electricity hydropower uses falling or flowing water to spin a turbine (part of the generation plant) . The rotating turbine blades spin a generator that converts that mechanical energy into electricity. The amount of electricity generated from each power plant depends on the quantity of the flowing water and the height from which it falls.

types of hydroelectric facilities

There are a few different types of hydropower facilities, all of which are based on the kinetic energy of moving water:

Conventional or Impoundment Hydro

Conventional or impoundment facilities use a dam to store water from a river in an artificial reservoir. When electricity is needed water is released from this reservoir, flows through and spins the turbine, which activates a generator that produces electricity.

Run-of-River or diversion facilities

This type of hydroelectric facility, also known as a “run-of-river” facility, channels part of a flowing river through a canal, either with or without an accompanying dam.

pumped hydro storage facilities

Like large water batteries, pumped hydro storage facilities are designed to store electricity that is derived from other energy sources, such as offshore wind farms, and then use that energy when it is needed most. Water is pumped uphill from one reservoir into a second reservoir at a higher elevation, and then released back through the turbines.

environmental benefits

Hydroelectric power is a source of renewable energy. As a way of generating electricity, hydropower has several key advantages that contribute to its widespread usage:

Hydroelectric power does not contribute to air pollution. Since it derives energy from flowing water, and does not require the combustion of any fossil fuels, it does not release greenhouse gases or other harmful air pollutants.
Hydroelectric power is highly local, reducing dependence on outside sources of fuel.
Hydroelectric power is a form of renewable energy.
Impoundment hydroelectric plants, in particular, create recreation areas as a byproduct. The reservoirs created by these projects can be used by people for swimming, fishing, and boating.
Hydroelectric plants generate power to the grid immediately. This means that they can very quickly go from no output to maximum output. During electricity outages and shortages, they provide a crucial backup for the system and are great complements to other renewable resources like wind and solar.
Hydropower facilities can be beneficial for flood control, irrigation, and maintaining the water supply.