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What Is Hydropower?

The Glen Canyon Dam producing hydropower on the Colorado River.

Hydropower (or hydroelectric power) is a term used to refer to electricity that is produced by harnessing the kinetic energy of flowing water. Hydroelectric dams are a common method of generating hydroelectricity and are considered highly reliable when built in the right environment.

The below sections provide further information on what hydropower actually  is and how it can be produced.

How Hydropower Is Generated

Moving or flowing bodies of water contain kinetic energy that can be harnessed to generate hydroelectric power. This can be achieved in a number of ways but most commonly through the use of a hydroelectric dam.

Generating Hydropower With Hydroelectric Dams

The turbine house of a hydroelectric dam.

A hydroelectric dam works by trapping a large body of water creating a reservoir which can then be used to drive turbines that are built into its structure. There can be many turbines fitted to a hydroelectric dam depending on its size.

Operators of a hydroelectric dam can control the flow of water from the reservoir which will follow a set path through the structure of the dam where it will eventually come into contact with the turbines making them revolve and thus generating electricity.

Generating Hydropower Through Other Means

We don’t always have to build giant hydroelectric dams to generate hydropower. Some companies have realised the potential of the kinetic energy stored in the flowing water of our rivers and have been able to build small scale hydroelectric installations. This technology is often referred to as “micro hydro” and allows power companies or even local businesses and homeowners to generate small volumes of hydroelectricity.

Micro hydro systems have a much smaller impact on the surrounding environment and can even be designed to harness the energy of flowing water without the need to dam a river. This is achieved through devices similar to water wheels (the type that used to power our mills and factories) which will simply turn with the natural flow of a river, generating low volumes of electricity that can be enough to power a small building.

Is Hydroelectricity Expensive?

Hydroelectricity is only considered expensive as a result of the initial cost of building a hydroelectric dam. This process involves lots of engineering and can take many years of planning and construction before a dam is completed. Once the initial cost of the dam is out of the way, the only costs associated with generating the electricity are operating and maintenance costs. Unlike non-renewable power stations, a hydroelectric dam doesn’t have to purchase any fuel to turn the turbines to generate electricity.

The Reliability of Hydropower

Hydropower is considered extremely reliable and efficient. A constant electricity supply can be easily achieved with the construction of a hydroelectric dam unlike some other renewable energy technologies such as solar panels (vulnerable to darkness) and wind turbines (vulnerable to wind levels).

In addition to constant electricity supplies, hydropower has the added benefit of been able to react quickly to changing electricity demands. As more electricity is required, the water intake can be increased to spin turbines faster or bring additional turbines online, almost in real-time Traditional power stations such as those fired by coal and oil can take significantly longer to adjust to these changing electricity demands.

Overview of Hydropower

Hydropower is key to providing a long-term and reliable supply of electricity in many areas of the world. Significant quantities of electricity can be generated cheaply with little to no pollution which is great news for the atmosphere and the air we breathe.

You might be interested in the following external resources to learn more about what hydropower is.