While wind and solar energy are in the spotlight, hydropower is still the oldest and most reliable form of renewable energy. And according to the 2020 Hydropower Status Report, it accounted for 4,306 TWh, the largest contribution from any renewable energy source.
Let’s take a look at the advantages and disadvantages of hydropower.
What is Hydropower?
Hydropower, or hydroelectric energy, is a process in which falling or running water is used to generate electricity. The water moves the turbine and turns its kinetic energy into mechanical energy. The end result is clean electricity.
Think of it much like how an alternator works on a car.
Advantages of Hydropower
Without exception, hydropower is the most reliable form of renewable energy in the world. The sun will go down, and the wind may stop blowing, but the water never stops flowing. This means clean energy is available 24/7.
This makes it a safe investment for any town or city.
2. You Can Adjust the Output
Most renewable sources are limited by the number of resources they receive. For instance, the amount of wind that blows a wind turbine. However, hydropower plants can actually control the flow of water, which means they can control the electricity output.
Therefore, when more energy is needed, more can be produced. And the opposite is true when less necessary.
3. Hydropower Remains the Cheapest Source of Energy
Hydropower is the cheapest source of energy for both renewable and fossil fuel. On average, it costs $0.05 per kilowatt-hour, and the states that generate the most electricity via hydroelectricity, have the cheapest electric bills in the country.
And for the record, that is the state of Washington.
4. Made to Last
Hydroelectric plants last for a very long time after construction. The lifespan is over 100 years! And as long as the plant receives regular maintenance, it can last even longer. In fact, with the right upgrades, their efficiency will improve.
This only adds to the financial stability that hydropower plants provide communities.
Disadvantages of Hydropower
1. Limited Building Opportunities
There are a finite number of rivers in the world capable of generating large amounts of electricity. As a result, hydropower plants can not expand quickly like other renewable sources.
To add to this dilemma, many of the water sources that can be used, are not close to cities.
Due to the difficulty of making new plants, hydropower is losing ground to wind and solar.
2. Droughts can Impact Hydropower Plants
Electricity is only generated when the water is flowing, and in normal circumstances, it should not be interrupted. However, droughts have impacted power plants in the past.
As the effects of climate change begin to worsen, droughts will become more common.
In an ironic turn of events, the technology that can prevent climate change, is susceptible to it.
3. Impact on Fish Populations
Hydroelectric plants require putting a dam in place to harness the power of flowing water. And as you might have guessed, this has a very negative impact on fish. In some cases, like Salmon, the fish can no longer reach their breeding grounds.
In other cases, the fish themselves fall victim to the turbines.
4. Risk of Flooding
In cases of extreme weather, the amount of water may increase drastically. This can cause flooding of the area. There are even catastrophic cases where the dam will actually break. In this event, the surrounding area is at risk.
The worst case in history was the 1975 Banqiao Dam failure, where 170,000 lives were lost.
While wind and solar energy are soaking up the spotlight, hydropower continues doing what it does best, being consistent. It is continuing to steadily grow around the world and remains an attractive investment for most regions that have the necessary water sources.
Robert has been following and writing about environmental stories for years at GreenGeeks. He believes that highlighting environmentally friendly practices can help promote change in every household.