Hydropower produces energy by moving flowing water through turbines, and it was the first large-scale renewable energy source that is used in the US, accounting for a third of the total electrical needs of the country in the 1940s. Since then, construction of dams peaked in the 1960s, though it has gradually declined from this time, and today, hydropower is just providing roughly 6% of the country’s electricity needs. This was due to the increased investment in other newer energy sources, rising environmental impacts of the dams and the siting limitations for large-scale hydropower plants.
Generally, hydropower is the one of the oldest and most renewable sources of energy in the world today. But while it is deemed as very beneficial, it also has its downsides. Here are the pros and cons of hydropower:
List of Pros of Hydropower
1. It uses a free resource.
Basically, this method of power generation uses water, which is a free energy source. Unlike fossil fuels, the price of water would remain constant and would not fluctuate based on economic and political factors.
2. It is efficient.
It is said that hydropower has very high energy conversion efficiency, where approximately, 90% of the captured energy will be able to be converted into electrical power. In fact, the energy conversion efficiencies for wind and solar are much lower, averaging about 59% and 15% respectively.
3. Its power plants do not produce pollution.
While hydropower accounts for 96% of the renewable energy in the world, its power plants do not pollute the water, land and air, unlike other power plants that greatly contribute to pollution that accelerates global warming.
4. It is renewable.
While the process of turning water into energy comes with its own cost, its source itself is renewable and free. Water sources for hydropower are basically renewed through evaporation and rain in a naturally regular way.
5. It can help improve environmental quality.
Dams constructed for hydropower purposes are actually contributing to the quality of the environment with better-quality water, better water supply to irrigate farms and a larger habitat for aquatic life.
6. It can keep up with demand.
One big advantage of hydropower is when there will be an increase in demand for such energy, and we can just add more power plants to existing hydropower dams, instead of having to build larger or additional dam sites. Also, hydropower that is being generated only uses a small fraction of the available resources.
7. It offers additional recreation.
The many dams created for hydropower have provided recreation opportunities for holidaymakers, such as fishing, camping, fishing and water sports.
8. It is cost-effective.
Basically, hydropower has a low level of energy cost compared with other conventional energy sources, such as coal and natural gas. Keep in mind that such an energy cost for hydropower in the US is just $0.08 per kW-hr, making it a competitive alternative to coal and other fuels that cost $.07-$0.14 per kW-hr.
List of Cons of Hydropower
1. It can destroy natural habitats.
Any power plant that is on an industrial scale will have some unfavorable effects on the environment. When a dam is to be built, there will naturally be changes to the environment so that it can be done. And, these changes can have significant contributions to the destruction of natural habitats.
2. It still emits carbon dioxide and methane.
Hydropower reservoirs can still release a large amount of methane and carbon dioxide, as the areas around them is filled with water, trees and plants that can start rotting and decomposing through other method without using oxygen. This would mean that these power plants can cause decomposition that can dump a great amount of carbon dioxide and methane into the environment, increasing pollution.
3. It can cause flooding.
Records show that construction of dams have actually caused surrounding towns to be flooded out and taken over by water, causing them to be non-existent or underwater ghost towns.
4. It offers limited use.
As hydropower is produced by the water that depends on yearly rain, this means that only the areas using this method and receiving a good amount of rainfall can take advantage of this technology.
5. It risks extinction of species.
Whenever a hydropower dam changes the habitats of animals that exist in the area of construction, there is always the risk of extinction to a certain species. Dams can cause problems with flooding, which endangers animal life. Other than this, dams can change the flow of rivers and other waterways that can cause water shortages to the neighboring communities and local livestock.
6. It requires high installation costs.
Although the operating costs of dams are believed to be low, the construction and installations of dams, as well as the turbines, can cost a lot due to the many regions not currently employing this alternative source of energy. If the initial cost had been less, then many countries have already used this energy source more commonly, but their construction actually requires a lot of labor and human capital, not to mention that their maintenance is very expensive.
7. It promotes siting.
Some hydropower sites in the US have been widely contested, as many of them were seen as a major loss for conservation efforts, like the construction of the Hetch Hetchy Reservoir and O’Shaughnessy Dam in Yosemite National Park in 1923. Many of these developments were actually stopped by bitter opposition from environmental groups, who consider that the government was only prioritizing development over the natural resources of a region.
8. It risks breaking of dams.
There is a lot of dams that were built for industrial use but are not currently used and removed as they can cause serious flooding. This would affect a huge number of people, including their property.
With this list of pros and cons of hydropower, you can weigh down your options on whether to use this alternative source of energy or not. All in all, what do you think?
Brandon Miller has a B.A. from the University of Texas at Austin. He is a seasoned writer who has written over one hundred articles, which have been read by over 500,000 people. If you have any comments or concerns about this blog post, then please contact the Green Garage team here.