Advantages and Disadvantages of Hydropower
Hydropower, hydroelectricity or hydroelectric energy is a form of renewable energy produced using the kinetic energy of the flowing water (streams and rivers) or falling water stored in large reservoirs.
The kinetic energy of the flowing or falling water is used to spin large and powerful turbines that are producing clean electricity using massive electromagnetic generators.
One of the first uses of hydro energy was for mechanical milling (grinding grains), but today, we are using the power of the water to generate clean electricity.
For mankind, hydropower is a very practical form of clean and renewable energy because we are using a natural resource (water) that is continually renewed (through the natural water cycle), and after producing energy, that water can be used for other purposes (in agriculture for irrigation, or as water supply) with minimal losses.
However, because hydroelectricity uses natural resources such as water in streams, rivers, etc., the presence of the spinning underwater turbines could affect the life of the animals and plants living in those ecosystems.
Advantages and Disadvantages of Hydropower
The power of the water has both advantages and disadvantages, because despite the fact that produces clean power without burning fossil fuels, it can also affects the environment and wildlife in the area where the hydroelectric power plant is built.
Advantages of Hydropower
Hydropower is the most developed source of renewable energy on our planet and has many benefits for our civilization.
1. Hydropower is a reliable energy source
Unlike solar and wind energy, hydropower or hydroelectric power is a reliable source of energy because water flows all the time, water can be diverted, and is used (water from the reservoir) to produce energy whenever is needed by a hydroelectric power plant.
The hydroelectric power plant can start generating energy in a very short time (in a couple of minutes, which is much faster than a power plant burning fossil fuels can do), and that energy is used to help the grid to cover the peak demand when needed.
2. Hydroelectric energy is a renewable resource
Hydropower is a renewable energy source because it uses a renewable resource of the plant represented by water.
Water on planet Earth is in a continuous movement due to the presence of the gravity, and the water cycle in nature that is powered by the Sun (another renewable resource).
Hydroelectric power plants are usually built on fast streams and rivers because the kinetic energy of the flowing water is used to produce clean electricity.
A hydroelectric power plant that uses a dam will have a very large reservoir of water that can be used when needed for power generation.
The reservoir is located at a higher altitude compared to the power plant, and the water released from the reservoir will pass through the dam to spin the turbines and will fall into a river located below.
Until we have water on the planet, gravity, and the water cycle will remain active, water will continue to flow and to be renewed every day, and hydroelectricity will remain a renewable source of power.
3. Hydropower creates electricity without releasing harmful emissions into the atmosphere
Despite other sources of conventional power, hydroelectricity is a reliable energy source (like conventional energy produced by burning fossil fuels), but produces clean power, which is free of harmful emissions.
Being an energy source with zero emissions, hydropower is not creating carbon emissions, acid rain, mercury or other pollutants, which means that hydroelectricity along with the other renewable sources of power available on the planet, is one of the energy sources of the future (because is clean and renewable).
4. A hydroelectric power plant using a dam attracts tourists
Hydroelectric power plants using dams are often considered tourist attractions.
The large volume of water in the reservoir could serve for recreational activities such water sports, and the dam itself quickly becomes a tourism hotspot.
5. Hydroelectricity pairs well with other sources of energy
Being a reliable source of electricity because a hydroelectric power plant can generate power when requested by the grid, hydropower can be paired with other sources of energy to cover the high demand of energy in the grid.
When paired with other sources of power, hydroelectricity is used as base-load power.
6. Hydroelectric power plants have a long life
Once built, the water reservoir, the dam and the hydroelectric power plant will generate free and clean electricity for many decades (even one century in some cases), which is a much longer period, compared to other forms of energy (power plants burning fossil fuels, and other renewables such as wind turbines and solar panels).
Disadvantages of Hydropower
Even if we talk about the most developed form of renewable energy available on the planet today, hydroelectric power also raises a few concerns.
1. Damming a river has a major impact on the local environment
When a dam is built for a new hydroelectric power plant, the construction of the water reservoir and the dam itself, will change wildlife habitats, can block fish passage, and often will force people in riverside communities to move out of their homes.
Dam built on the Mekong River in China. pixabay.com
Dam failures can be catastrophic for people and wildlife living downstream.
2. Greenhouse gas emissions are released during the construction of the dam
When building the water reservoir, the area flooded with water can generate greenhouse gas emissions due to the fact that the plants in the flooded area die and decay underwater, which will release large amounts of harmful gases (methane) into the atmosphere.
When building the dam and the hydroelectric power plant, the large volume of cement used in the process will also generate greenhouse gas emissions (carbon emissions).
3. Constructing the water reservoir is a major challenge
Building the massive reservoir of water will not only produce greenhouse gas emissions and affect the lives of the riverside communities, but will also occupy a very large area of land, and represents a major challenge in terms of time consumed, money invested and workforce.
The driveways constructed to access the dam will consume even more useful land.
4. Heavy rain can produce floods which will affect the life of the riverside communities
Heavy and prolonged torrential rain can produce floods that will cause mass damage to wildlife and people living near the river.
Heavy rain can produce floods which will affect the life of the riverside communities.
5. Constructing the reservoir or damming a river will affect wildlife
Constructing a major water reservoir or damming a river will also have adverse ecological effects on wildlife, fish, farms, forests and human populations.
6. Water in a reservoir is stagnant
Water in the reservoir used by the hydroelectric power plant is stagnant, gathering more sediment and growing more aquatic weeds and algae that the river would.
This is causing additional problems to downstream life because fish are used to a certain level of temperature and oxygen in their river water.
Dams are not only blocking fish migration, but the stagnant water in the reservoir is cold and contains a small amount of oxygen.
Opening the dam for energy generation will make the cold and barely oxygenated water from the reservoir to rush into the rivers and suffocate the fish living there.
7. Earthquakes are a major concern form hydropower
In some areas of the planet (China and India), the construction of major dams and reservoirs has led to massive earthquakes in these regions.
A powerful earthquake can break the dam, and this would produce catastrophic floods that will severely affect the people and wildlife living downstream.
Final conclusion
Hydropower along with the other forms of renewable energy will evolve in the future by increasing the security of the dams and water reservoirs, and by decreasing their effects on the ecosystems.
However, if mankind will achieve nuclear fusion, the construction of new dams may no longer be needed, and this way the streams and rivers will remain untouched.
