Hoover Dam between Nevada and Arizona in the US

Hydropower facts and statistics

Hydropower is the cornerstone in the global pursuit of renewable energy. Therefore, it is worth understanding the role of hydropower in today’s world.

Whether you are a hydropower advocate or sceptic, you will naturally have some questions about it that you want specific answers for. For example:

  • How much energy does hydropower generate?

    Hydropower, Hoover Dam between Nevada and Arizona in the US
    Hoover Dam between Nevada and Arizona in the US.
  • In what ways is it good or bad for the environment?
  • How many new hydroelectric facilities are planned for the future?

We will answer these questions and others with the facts and statistics we have collected below. Join us as we explore some key insights surrounding hydroelectric power, sorted into these categories: worldwide statistics, environmental impact, costs, the future, and everything else.

Worldwide statistics

A leader in power supply

Hydropower currently accounts for 20% of the world’s total electricity and 90% of global renewable energy.

The world’s largest dam

Regarding installed capacity, the largest dam in the world is the Three Gorges Dam in the Yangtze River. The dam itself measures approximately 181 metres tall and 2,335 metres long. (National Geographic).

You can find out more about the Three Gorges Dam in our blog: Exploring examples of hydropower.

The most significant energy generator

Though it may be the largest dam globally, the Three Gorges does not generate the most electricity annually. This title is instead held by the Itaipu facility, located on the Paraná River between Brazil and Paraguay. (National Geographic)

US energy production

In 2015, hydropower generated around 6% of all the United States’ energy. (University of Wisconsin)

Norway’s leading power supply

As of 2019, Norway has more than 1240 hydropower storage reservoirs. Most of these reservoirs were constructed before 1990, and their total capacity accounts for approximately 70% of Norway’s total annual energy consumption. (NVE Report 2019)

Environmental impact

Hydroelectric power is one of the cleanest energy sources

As stated in independent research published by the International Atomic Energy Agency, the use of hydropower, compared to other fossil fuels for the generation of electricity, has aided in avoiding the release of approximately 100 billion tonnes of carbon dioxide into the atmosphere in the last 50 years alone (IAEA).

Risks to natural habitat

In the construction of the majority of hydropower facilities, species of marine life have been displaced from their habitats. In the Columbia River Basin, for example, it is estimated that native salmon and steelhead populations have lost access to approximately 40% of their historic habitat. (National Geographic)

Hydropower saves money by protecting against floods

When heavy rainfall or rising upstream water levels pose a flooding risk, hydroelectric dams avert floods by storing and regulating water, or releasing it through emergency spillways. Infrastructure damage and loss of property due to flooding have an economic impact, but it is estimated that losses (when measured in GDP) can be reduced by 12-22% and save 53-96 billion USD. (iha)


 Low-cost generation

For global hydropower projects in 2018, the weighted average cost for generating this power was US$0.047 per kWh (IRENA). This made hydropower the lowest-cost energy source in most global markets.

Less favourable construction

While generating hydropower tends to be very cost-effective, constructing hydropower facilities can be much more expensive in comparison to fossil fuel counterparts. But this is the price to pay to continue the energy transition.

The future of hydropower

Global capacity still needs to grow

As seen in a publication by the International Renewable Energy Agency (IRENA), global hydroelectric power capacity will need to grow by approximately 60% by the year 2050 to reach a desired 2,150 GW. Achieving this will help keep global temperature rise below 2 degrees Celsius.

European hydropower is expanding

According to the WWF, despite the existence of 21,387 hydropower plants spanning the entirety of Europe, there are plans to construct up to 8,785 additional plants.


Supporting the United Nations and SDGs

When responsibly developed and operated, hydropower facilities support 4 of the 17 SDGs. The specific SDGs that hydroelectric power directly supports are clean water and sanitation, affordable and clean energy, industry, innovation and infrastructure, and climate action.

Thwarted by droughts

In recent years, recorded rainfall in Western countries (specifically the US) has drastically decreased. With this change in rainfall, the amount of water stored in dams and reservoirs has also decreased, limiting energy generation and accessible drinking water. (Water Resources Research Centre)

Do you work in hydropower?

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  1. National Geographic
  2. University of Wisconsin
  3. Norwegian Water Resources and Energy Directorate Report 2019
  4. International Atomic Energy Agency Publication
  5. International hydropower Association (iha)
  6. International Renewable Energy Agency (IRENA), Renewable Power Generation Costs 2018
  7. Renewable Energy World
  8. International Renewable Energy Agency (IRENA), Global Renewables Outlook
  9. World Wide Fund For Nature(WWF)
  10. United Nations SDGs
  11. Water Resources Research Centre