Hydropower, also called hydroelectric power, is the most utilized form of renewable energy. Hydropower is the process of conversion of energy from flowing water into electrical energy/electricity. Hydropower was one of the first sources of energy used for electricity generation. Hydropower accounts for around 18% of total electricity production.

Advantage and Disadvantages of Hydropower
Photo by American Public Power Association on Unsplash

Advantages and Disadvantages of Hydropower

Hydropower produces electricity using turbines and generators, where mechanical energy is generated when flowing water spins rotors on a turbine. The turbine is connected to an electromagnetic generator when the turbine spins electricity is generated.

Because the source of hydroelectric power is water, hydroelectric power plants are usually located on or near a water source. The volume of the water flow and the elevation of the dam determines the amount of available energy in moving water. Generally, the greater is the water flow and the higher is the elevation of the dam, the more electricity can be produced.

It is important to understand that hydropower relies on the water cycle. Seasonal variation directly affects hydroelectricity production as water flow varies with seasons. For example, during the rainy season, the water flow is maximum while it is a minimum for summer. Also, some water sources dry in summer.

Hydropower is a flexible and reliable source of electricity compared to other renewable energy sources available. Hydropower is an abundant, low-cost source of power though it has a high building cost. China is the largest producer of hydroelectricity followed by the United States, Brazil, Canada, India, and Russia.

Advantages and Disadvantages of Hydropower

Hydropower has the ability to generate electricity without emitting greenhouse gasses. However, it can also cause environmental and social threats which can’t be ignored. Let’s discuss some of the major advantages and disadvantages of hydropower:

Advantages of Hydropower

1. A Cheap Source of Energy

Despite expensive upfront building costs, hydroelectric power is one of the cheapest sources of energy. The good thing about hydroelectricity is they require a low cost of maintenance and operation. Also, dams are designed for long-term use and are therefore capable of producing hydroelectric power up to an average lifetime of 50 – 100 years. Like other fossil-based sources of fuel such as oil or gas, there is typically no production costs linked to hydropower as water is naturally available and is free.

2. The Renewable Nature

Hydroelectricity is considered a renewable source of energy as it uses the earth’s water to produce electricity. Water is a never-ending source as water is recycled back through the water cycle. The sunlight evaporates water from the earth’s surface, forms clouds, and then falls back on to the earth in the form of rain and snow. During the production of hydroelectricity, water is not used up. So we don’t have to worry about the availability of water as we will never run out of supply.

3. Clean Energy Source

Hydropower is one of the clean and green alternative sources of energy. Unlike traditional fuel energy sources, hydroelectric energy doesn’t release harmful pollutants into the environment. It is one of the most environmentally-friendly forms of energy production available to us today.

Hydropower doesn’t rely on fossil fuels to produce energy, rather it uses water and the process is so clean that it doesn’t release any greenhouse gases or harmful waste into the environment. In this way, hydropower helps migrate climate change and keep our environment clean and green.

4. Flexible

Hydropower is a flexible source of energy as hydropower plants can be scaled up and down easily to meet the changing energy demands. When the electricity demand is high, the flow of water can be increased and can also be decreased when the demand falls.

This means that electricity can be made available when it’s needed, which reduces energy waste. Unlike solar and wind energy, which are only available at a specific time but water is always available for electricity production and does not depend on weather conditions.

5. Efficient and Reliable

Hydropower is one of the most efficient energy sources in the world. Solar energy is only 30-35% efficient, wind energy is 25-45% efficient, coal power is 33-40% efficient but hydropower is up to 90% efficient. Hydroelectric power is not dependable on any outside conditions like weather conditions or oil/fuel prices, however, it depends on the amount of water flow. Hydropower is a very reliable energy source. Countries having large resources of hydropower use hydroelectricity as a baseload energy source.

6. Safe

Compared to other fossil fuels and nuclear energy, hydroelectricity is much safer. There is no fuel(other than water) used in the process, so there are fewer chances of accidents compared to nuclear power and fossil fuels. No combustion fuel or any reaction is happening in the process, hence it is much safer. However, there are issues related to poor construction and low safety standards in old dams.

Disadvantages of Hydropower

1. Environmental Damage

The main con of hydropower is its effect on the environment. Interruption in the natural flow of water has serious impacts on the river ecosystem and environment. This leads to disrupted animal migration paths, issues with water quality, and human or wildlife displacement. Fishes are directly affected as blocking the flow of water can also seriously impact fish migration. New roads and power lines must be installed to build a dam that disrupts the environment.

2. High Building Cost

Hydroelectric Power plants are incredibly expensive to build, however operating cost and maintenance costs are minimal. Hydropower infrastructure includes a dam, a reservoir, and power-generating turbines. Dams are extremely expensive to build and must be built to a very high standard. Also, hydropower projects take a long period to finish and will have to operate for a long period to recover the capital spent.

3. May Cause Droughts

Water availability directly affects electricity generation. The occurrence of local droughts is one of the major downsides of setting up hydroelectric power plants. The overall cost of energy is calculated depending on the availability of water and drought could potentially affect electricity production rate. The problem of droughts may become even worse in the future due to global warming.

4. Risks of the Flood

As dams hold back large volumes of water, which can be catastrophic to downriver settlements and infrastructure. A poor-standard construction, natural disasters, or sabotage can cause the flooding disaster. It can not only affect the livelihood of people living in these areas but also vegetation, agricultural fields, animals, etc. This has a large impact on communities as it displaces people from their habitats.


Hydropower is the most popular energy source which currently supplies millions of people with electricity. Despite a few drawbacks, there’s no denying that it is an efficient and renewable source of energy for a sustainable future.

Although hydroelectric power plants can be good alternative sources of energy for the increasing energy needs, there are issues that can limit their creation. For this reason, it is essential to analyze the advantages and disadvantages of hydroelectricity when planning to build one in a specific location so that it doesn’t affect the environment and the lives of people nearby.