Renewable hydropower is a reliable, versatile and low cost source of clean electricity generation and responsible water management.
Modern hydropower plants are helping to accelerate the clean energy transition, providing essential power, storage, flexibility and climate mitigation services.
Hydropower is also a key asset for building secure, clean, electricity systems and reaching global net zero targets.
Pumped storage hydropower | Regional interconnections
Greenhouse gas emissions | Green bonds | Resettlement
Fish and aquatic biodiversity | World Heritage and Protected Areas
There are four main types of hydropower plants: run-of-river, storage, pumped storage and offshore hydropower.
Only a small minority of the world's dams are built for hydropower, with the majority used for irrigation, water supply, flood control and other purposes.
Many hydropower dams are used for multiple purposes beyond electricity generation, providing infrastructure to supply clean water for homes, industry and agriculture, as well as recreation and transportation services.
Hydropower projects can be used to regulate and store water to mitigate the impacts of extreme weather events such as floods and drought, which are on the rise due to climate change. More.
Around 60 per cent of all renewable electricity is generated by hydropower. The sector produces about 16 per cent of total electricity generation from all sources.
In its 2021 Hydropower Special Market Report, the International Energy Agency (IEA) reports that hydropower accounts for nearly a third of the world’s capacity for flexible electricity supply and has the potential to provide even more.
No country has come close to achieving 100% renewables without hydropower in the energy mix.
Hydropower installed capacity reached 1,330 gigawatts (GW) in 2020 as generation hit a record 4,370 terawatt hours (TWh). China, Brazil, the USA, Canada and India are the largest hydropower producers by installed capacity.
China, Brazil, the USA, Canada and India are the largest hydropower producers by installed capacity. More.
Between 2015 and 2019, the average year-on-year worldwide growth in hydropower installed capacity was 2.1 per cent.
Hydropower is an ideal complement to variable renewables like wind and solar, thanks to its flexibility and energy storage services.
Hydropower can meet demand when these intermittent sources are unavailable. Pumped storage hydropower, operating like a green, rechargeable battery, absorbs energy when supply exceeds demand.
Hydropower is among the cleanest sources of electricity, with a low greenhouse gas emission intensity compared to other energy forms.
Independent research suggests that use of hydropower instead of fossil fuels for electricity generation has helped to avoid more than 100 billion tonnes of carbon dioxide in the past 50 years alone, exceeding even the emissions averted by nuclear power. That’s roughly equivalent to the total annual carbon footprint of the United States for 20 years.
Over the life cycle of a power plant, hydropower offers some of the lowest greenhouse gas emissions per unit of energy generated – as well as multiple environmental benefits. (IEA Hydropower Special Market Report 2021)
If hydropower was replaced by coal, IHA estimates up to 4 billion tonnes of additional greenhouse gases would be emitted annually, increasing global emissions from fossil fuels and industry by 10 per cent. There would also be 150 million more tonnes of air polluting particulates emitted each year.
According to the International Renewable Energy Agency (IRENA), the world’s existing hydropower capacity will need to grow by around 60 per cent by 2050 to reach 2,150 GW to help limit the rise in global temperature to well below two degrees Celsius.
The IEA has reported that 1,300 GW of additional hydropower capacity is required in order to keep temperature rises to within a 1.5 degree target.
Such growth would help generate some 600,000 skilled jobs over the coming decade and would require an estimated investment of US$1.7 trillion.
Global investment in hydropower topped US$50billion in 2019 according to the International Energy Agency (IEA), far short of the estimated US$100 billion a year required to help meet the organisation's Sustainable Development Scenario.
Hydropower provides very low cost electricity over its long lifetime, despite relatively high upfront construction costs.
The global weighted average cost of electricity from hydropower projects in 2018 was US$0.047 per kWh, making it the lowest-cost source of electricity in many markets (IRENA).
Hydropower provides an opportunity to generate significant revenue from exports to neighbouring countries. In addition, the hydropower industry directly employs around 2 million people worldwide, and many more in connected supply chains (IRENA)
Hydropower projects of all sizes can result in net-benefits to communities and the environment, provided they have a strategic fit in a river basin and are responsibly developed and operated.
The Hydropower Sustainability Tools exist to ensure that projects can be developed and operated in accordance with good practice. These guidelines and assessment tools cover 26 environmental, social and governance performance criteria.
Governed by a multi-stakeholder group of civil society, industry, governments and financial institutions, the tools are aligned with safeguards developed by the World Bank and other organisations. More.
Sustainable hydropower supports the achievement of the United Nations Agenda for Sustainable Development, as well as the Paris Agreement on climate change.
The 17 Sustainable Development Goals were adopted by all member governments of the United Nations and provide a blueprint of priorities for national governments, multilateral organisations, business and civil society.
When responsibly developed and operated, hydropower projects can directly support the achievement of SDGs 6, 7, 9 and 13:
Goal 6: Ensuring availability and sustainable management of water for all
Goal 7: Providing access to affordable, reliable, sustainable and modern energy for all
Goal 9: Upgrading infrastructure with clean, environmentally sound technologies
Goal 13: Taking action to combat climate change and its impacts