What is Hydroelectricity?

What is Hydroelectricity?

Hydroelectric power, otherwise called hydroelectricity, is generated by the force of falling water. While that may be an oversimplified version of how hydroelectric power works, it can definitively be categorized as a renewable type of global energy. Sustainable power allows us to tap into naturally replenishing assets, like water or wind. According to the World Energy Council:

  • The global hydroelectric power market accounts for nearly two-thirds of our renewable global energy
  • Hydropower’s continued surge is projected to double by the year 2050.

So what exactly is hydroelectricity? Why is it important? Renewable resources are important as we continue to witness shifts in the total expenditure of non-renewable assets like coal and oil. Over the last century, many methods have been developed to produce the power that machines need to run. With limited resources always a concern, the world is increasingly becoming interested in more sustainable methods for producing energy. However, this has proven challenging as many are not easy to build and operate on a large scale.

Hydropower Dam

Fortunately, hydroelectricity development and advancements have proven to be successful. In this article, we will discuss what hydroelectricity is and how it produces one of the greatest forms of energy called hydropower. Hydroelectricity is one of the “cleanest” sources of energy to date and may help the global movement in making power affordable and accessible to families, farms, factory plants and so much more.

Companies like Gracon, are able to provide assistance in building these sources of power. We provide hydroelectric construction, inspection, disassembly, rehabilitation, replacement, testing among other services.

How Hydroelectricity Works

Simply put, hydroelectricity is the process by which we convert water into electricity. A simple breakdown to explain how hydroelectricity is as follows:

    • Water is used to turn a propellor-like piece (turbine)
    • The turbine then turns a metal shaft in an electric generator
    • The generator acts as a motor that produces the electricity

This form of generating electricity is obviously a very complex and technical procedure, but it can be explained at a basic level in fairly simple terms. A mechanical structure is built which uses water and gravity to generate electricity. One of the main components in the machine is a turbine, which is basically a large propeller. The turbine is connected by a metal shaft to a generator, and it’s housed inside of a specific chamber. When water is allowed to flow through, it spins the turbine as it passes. This spinning of the metal shaft powers a motor that creates the electricity.

After this process is completed, the electricity can be sent out of the hydroelectric power station through cables and transferred wherever needed.

Origins of Hydroelectricity

According to the International Hydropower Association (IHA), hydroelectricity was first used successfully in 1878, England.

It’s not a new concept that water is used in the process of creating power. It is, however, new that technology allows it to generate electricity. Our modern use of it can be traced to the increased interest in power generation during the industrial revolution, and the first hydroelectric power was successfully used in England in 1878. Shortly after, in 1882, the world’s first hydroelectric power plant began operation on the Fox River in Appleton, Wisconsin. That started a trend of building facilities all around the country.

Over the years, the projects became bigger and more advanced. Eventually, governments had to step in to regulate (and often pay for) the dams and power stations because of the massive scale. Today, hydropower provides about 96% of renewable energy in the United States. As a note, other renewable resources include geothermal, wave power, tidal power, wind power, and solar power. As noted above, hydroelectric power stems from falling water. More specifically, hydroelectric power comes from flowing water — winter and spring runoff from mountain streams and clear lakes. Water, when it is falling by the force of gravity, can be used to turn turbines and generators that produce electricity.

What is Hydroelectricity

Hydroelectricity Methods

Even though the overall process is the same, there are a few different methods that are commonly used to generate electricity using water. These methods include:

  • Dams
  • Run-of-the-River
  • Pumped Storage

Dams: The most common method is done by using dams. Water is blocked up into a reservoir, and it can be sent through in controlled volumes to allow for specific amounts of power. The size of the body of water and the elevation change determines how much power this method can generate.

Run-of-the-River: Another way of generating hydroelectricity is the run-of-the-river method. This is where a similar mechanism is built as in a dam, except it’s in a location where water is constantly flowing through, such as a river. The reason that this isn’t as popular is that the water can’t be controlled, so it can only generate a fixed amount at any given time, and the excess is wasted.

Pumped-Storage: A third method is called pumped-storage hydroelectricity. This is also commonly used in dams, but it essentially recycles the water in a reservoir. It is first allowed to travel to a lower elevation (while generating electricity), and it is later pumped back to the higher point. This takes advantage of powering the pumps with cheap electricity during slow hours and selling the generated power during peak times.

Even the tide can be used to generate hydroelectricity. This method uses the same concept as the others, but with tidal changes as the shifting water. If offers far less control and power output, but it can be built in more areas.

Another method is using underwater currents to generate power. The most common way of doing this is building a large water wheel in a location where there is a strong movement beneath the surface.

Why Hydroelectricity is Popular

There are many reasons why hydroelectricity is popular, but here are some of the key factors:

  • Renewable – it only requires water, which is a resource that continues to replenish
  • Affordable – once the facility is built, there aren’t any additional costs, so it is cheaper than many other methods to generate power
  • Ability to change output – can change quickly to meet demand, especially when using a dam
  • Environmentally friendly – it doesn’t cause pollution

In addition to these, hydropower mechanisms do not pollute the water, air, or environment. As we continue to address the need for sustainable resources, hydroelectric power is a booming market and business. As such, the government often funds and regulates hydroelectric projects.

On the flip side, there are some cons to hydroelectric plants. For one, dams and hydroelectric projects are often quite large and take up incredible landmass sizes that disrupt ecosystems and surrounding archeology and important, significant sites, as well as the possible displacement of surrounding communities. Despite these losses, hydroelectricity continues to be a go-to for renewable energy and likely because it has been around longer and is one of our most developed technologies.

Different Sizes

Hydroelectric projects built on a massive scale get the most attention, but it’s not only used successfully with giant dams. This method can be used in many sizes, including at a micro level to power remote buildings.

Hydroelectricity Dam

Where Hydroelectricity is Popular

Generating electricity in this way is popular globally, and it’s done in about 150 countries. Some countries generate the majority of their power this way, such as Canada, Brazil, Norway, and New Zealand. China is the single largest producer.

World’s Largest Facility

The largest hydroelectric facility in the world (determined by installed capacity) is the Three Gorges Dam on the Yangtze River in China. It was completed in 2012, and the 32 turbines are able to generate 22,500 megawatts.

Plenty of Potential

Hydropower is continuing to grow and in the USA alone powers over 30 million homes. There are currently many dams in place that are not even being used to generate power, so there’s plenty of potential to grow this number.