The world has tapped into countless ways to generate power. And one of the most powerful engines of nature is water. To gain an understanding of how water can be used to generate electricity, you have to learn the pros and cons of hydroelectric energy.
Utilizing moving water is something that humankind has been doing throughout history. For centuries, people have used water to power mills for grinding grain and producing flour.
Hydroelectric energy is not a new concept in the United States. The average facility has been in operation for more than six decades. So you may have already seen massive amounts of water stored in dams in many parts of the country. Some dams have even become tourist spots.
Despite the many forms of renewable energy, including hydroelectric energy, the U.S. (as well as the rest of the world) currently prefers nuclear power plants and fossil fuels. Once you know the pros and cons of hydroelectric energy, you may get a clearer picture of how millions of people can effectively utilize it.
What Is Hydroelectric Energy?
Before you assess the pros and cons of hydroelectric energy, you first have to know what it is.
Hydroelectric power is a form of renewable energy. It is responsible for 96% of the United States’ total renewable energy. Other renewable energy sources that make use of water are tidal power and geothermal.
Without flowing water, there is no hydroelectric power. When water falls due to gravity, it powers generators and turbines that generate electricity.
What makes hydroelectric energy unique is it does not use additional resources to generate electricity. It also does not pollute water and land compared to other types of power plants.
Throughout the years, hydroelectric power generated in both large and small hydroelectric plants has played a significant role in the development of the world’s power industry.
There are many excellent books available to learn more about the pros and cons of hydroelectric energy in greater depth.
Importance Of Hydroelectric Energy
Hydroelectric energy helps create, build, and expand resources. Over 40 percent of electric power produced in the 1920s came from hydroelectric plants.
Considering its successful history, you might think hydroelectricity now dominates electricity production globally. However, that is not the case. Although hydroelectric power has grown at a steady rate since its introduction, other sources of energy have surpassed it.
On the one hand, compared to other renewable sources of energy, hydropower is the most common in the world. Yet, hydroelectricity accounts for only 17 percent of total electricity production worldwide.
Hydroelectric power can also feature in small scale projects, but for industrial-scale use, it substantially lags behind fossil fuels.
Throughout the years, China has championed the use of hydroelectric energy. Also, Canada, Brazil, and the United States rank highly in hydroelectricity production.
Despite knowing the pros and cons of hydroelectric energy, people still haven’t tapped into the vast potential of hydroelectricity production in meeting global needs. And there are still many areas left undeveloped, such as large parts of Asia, Central Africa, and Latin America.
To put this in perspective, the Bureau of Reclamation has 58 power plants in the U.S. today. These power plants produce more than enough power to meet the needs of 14 million people. This amount of energy is equivalent to 42 billion kilowatt-hours.
The astonishing fact is that 72 million barrels of oil are needed to produce this amount of energy. Considering this fact, hydroelectric power seems to be a more efficient method of energy production.
Projects also last longer compared to other types of energy generation.
Hydroelectricity generation also fares well in responding to changing conditions.
How Does Hydroelectric Power Work?
Before you consider the pros and cons of hydroelectric energy, you need to master the concept of how it works. As established in the previous section, hydroelectric power cannot be made without water in motion, just like how solar energy cannot produce electricity when there is no sun.
Energy cannot be created nor destroyed in nature. Energy simply changes its form. There is no new energy created using hydroelectric power plants. Another form of energy converts into electricity.
To generate power, water must move. This process is called kinetic energy. The water in motion turns the turbine’s blades, and the kinetic energy changes into mechanical energy. Then, energy is finally converted into electricity. Because the first source of energy is water, it is called hydroelectric power.
All hydroelectric power plants make hydropower. These plants are usually within dams. A dam stores a large volume of water to facilitate essential activities such as irrigation, industrial and domestic use, and power generation. The dams act as a reservoir that stores water in order to make power.
At a dam, water flows from a great height. A pipe transports the water to reach the turbine. Then, the fast-moving water pushes the blades of the turbine, which produces a movement that is similar to when a pinwheel comes in contact with the wind.
The water then turns the rotor of the generator. When the generator sweeps by the rotor’s wires, electricity forms. The water then flows unchanged so it can serve other purposes. This event happens when the demand for energy is low, such as in the middle of the night.
Aside from dams, there are also power plants located on canals, streams, and rivers.
Pros And Cons Of Hydroelectric Energy
Now you know how this type of energy forms. So next, we consider the pros and cons of hydroelectric energy to further our understanding.
Hydroelectric power features many incredible advantages.
Renewable and clean
A significant benefit of using hydroelectric energy is that water is the fuel source. Water is renewable because the sun evaporates water from the earth, forms clouds, and then the gas falls back to earth in the form of rain and snow. This cycle is why hydroelectric power that comes from lakes and rivers is a sustainable source of energy.
Because of the nature of water, people don’t have to worry about using it all up to generate electricity.
With its renewable identification comes another advantage -- hydroelectric power is a clean energy alternative. Generating power through hydroelectric power plants won’t contaminate other resources.
The energy produced in hydroelectric plants does not give off greenhouse gases or toxic byproducts that can pollute surrounding areas. The only major contamination usually happens when the power plant is built.
Compared to fossil fuels, hydroelectric power plants help alleviate smog, acid rain, and the climate crisis.
Because of the stability offered by flowing water, hydroelectric production is reliable. That is, the production of hydroelectric power features very little fluctuation.
This reliability is why many nations feature hydroelectric energy as a major energy source. As long as water is present, power production is possible.
Hydroelectric power plants are an important component of sustainable development. This model encompasses the idea of providing for society’s needs without harming the resources available for future generations.
That quality makes hydroelectric energy a sustainably sensible, socially responsible, and economically practical energy source.
Low operating cost
One of the reasons why more communities prefer hydroelectric power is because of its cost-competitiveness. Although the cost of building a hydroelectricity generating facility is high, market volatility does not affect the water stored in dams, lakes, and rivers.
The same cannot be said of the prices of coal, oil, natural gas, and other sources of fossil fuels that can feature wild fluctuations in price.
Even the cost of building the facility can be justified because on average, hydroelectric power plants last five decades to a hundred years, making it an excellent investment for generations.
The Hoover Dam was completed in 1941 and provides enough electricity for about 1.3 million people a year. It's expected to last longer than human civilization. That's an extreme example, but you get the idea.
Dams can also be easily upgraded to meet technological requirements while not increasing operating costs.
Can supply current demand
It is relatively simple to turn water into electricity. Although it requires a complicated facility, it won’t be challenging to operate.
This feature makes hydroelectric power a top choice for communities with low or high power usage. The relatively low need for specialized skills is another benefit for communities with limited resources.
Has recreational and practical opportunities
Whether it’s fishing, swimming, boating, or picture-taking, the lakes formed by dams provide a myriad of recreational opportunities. And the dam itself can even become a tourist attraction.
Hydroelectric power plants can attract more people to visit remote areas since it can inspire the construction of highways and other industries. These activities will help the local economy, which can, in turn, benefit the education, healthcare, and quality of life of its residents.
Aside from these purposes, the water from the hydroelectric power plants can provide irrigation. Dams can store huge volumes of water, which can be an important resource when rainfall decreases, or there is a water shortage.
Its ability to store water is a major advantage since it keeps water from being exhausted. It also minimizes communities’ susceptibility to floods and droughts.
Just like all sources of energy, hydroelectric power is not perfect. To complete your understanding of the pros and cons of hydroelectric energy, take a look at some of the major drawbacks of using hydroelectric power.
Hydroelectric energy can cause interruptions in the natural flow of water. This event could have a detrimental effect on ecosystems and the environment.
Species of fish and land animals migrate when the breeding season begins, or when there is a food shortage in the area. Dams could also block their path. This situation can result in death or the lack of reproduction of endemic species in the area.
Aside from the altered flow of water, hydroelectric power plants feature power lines and streets, which can ruin the ecosystems.
Ideally, environmental studies will help limit the impact, but it's impossible to have zero impact on the environment when building a dam.
While hydroelectric power plants may help communities when there is a water shortage, these facilities can negatively affect areas with lower elevations.
These places are vulnerable to unusually strong water currents created by the dam. This event could destroy livelihoods. Damns may force communities to relocate homes so that the dam can continue operations.
A potentially devastating effect of hydroelectric power plants is local drought. The power and energy produced by hydroelectric power depend solely on the accessibility and amount of water in the area.
A lack of precipitation affects the accessibility of water. These conditions can lead to local communities not getting the electricity they need.
While dams can greatly help some communities, dams can also alter the flow of water in another area. That can result in a shortage of water, which could lead to conflict. The most recent example of this is a dam Ethiopia is building on the Nile upriver of Egypt, which relies heavily on the Nile for water.
Methane and carbon dioxide emission
Hydroelectric power plants operate near large bodies of water. And the plants in the water may rot and decompose without oxygen.
This situation releases methane and carbon dioxide, which intensifies pollution caused by the dam.
Construction is expensive and complicated
Although the operating cost is low, hydroelectric power plants require high capital costs in its introduction. Since the 1950s, more than $2 trillion dollars have been spent on dams.
This problem should come as no surprise since it is expensive to build all types of power plants. Aside from being costly, hydroelectric power plants also take a long time to build.
Not only are hydroelectric power plants expensive, but some problems may also come up due to underwater foundations, topography, and materials. The power plants operate for a significant period of time before recouping initial costs.
The construction of reservoirs can displace both people and animals. Dams have affected whole villages, towns, and cities, especially local indigenous peoples.
People may need to relocate after spending their whole lives in a particular place. Although they are compensated, it still won’t be enough to make up for everything they are giving up.
If they do refuse to move out, they may be threatened with violence. This situation is what happened in Guatemala in 1982, where 400 Mayans died because of the Chixoy Dam.
What Do You Think About Hydroelectric Energy?
Hydroelectric energy is a double-edged sword. While dams can help many areas by generating power, dams can also be the cause of various challenges.
Now that you know the pros and cons of hydroelectric energy, you can determine whether or not it’s a viable idea to introduce in your area.
The best thing to do is to thoroughly analyze the local conditions and safety requirements, and ensure that the power plant would not affect the environment and local inhabitants.
Know of any other pros and cons of hydroelectric energy? We’d love to read your thoughts in the comments below!