Hydropower is the largest source of renewable electricity in the world, producing around 16% of the world’s electricity from over 1 200 GW of installed capacity. Annual net capacity growth has slowed in recent years, due to fewer large projects being developed in China and Brazil. However, cumulative capacity is still expected to increase by an additional 125 GW by 2023. China is likely to grow at a slower pace than in the past but would still account for over 40% of the net growth, followed by additions from other markets in Asia, Latin America, and Africa.

Hydropower is expected to remain the world’s largest source of renewable electricity generation by 2023 and will play a critical role in decarbonising the power system and improving system flexibility. As such, developments can be expected in market segments that can contribute to this flexibility such as refurbishment of existing hydro plant and pumped storage projects.

	Accelerated case	Middle East	Africa	Eurasia	Latin America	APAC	North America	Europe	China
2017	0.00	16.73	34.24	84.93	174.45	188.31	196.24	231.02	343.59
2018	2.81	16.93	37.88	85.78	178.35	193.27	196.59	234.07	349.19
2019	6.05	17.18	39.30	87.55	185.06	198.42	197.11	235.63	358.29
2020	10.76	17.29	41.07	88.50	187.30	203.37	197.68	236.99	366.59
2021	15.65	17.47	42.69	88.86	188.97	208.38	198.46	237.69	372.69
2022	19.32	17.84	44.63	89.86	191.32	213.22	199.00	238.38	382.19
2023	30.56	18.22	46.70	90.68	192.69	216.89	199.73	239.18	390.89

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		"text": "Hydropower generation and cumulative capacity by region, 2017-2023"
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Source: Renewables 2018

Hydropower is a mature technology, yet it continues to evolve. Reservoir hydropower plants and pump storage plants are particularly suited to providing system flexibility, while run-of-the river hydropower plants are themselves variable according to current or seasonal weather conditions.

  • Run-of-river hydropower plants harness energy for electricity production mainly from the available flow of the river. These plants may include short-term storage or “pondage”, allowing for some hourly or daily flexibility but they usually have substantial seasonal and yearly variations.
  • Reservoir hydropower plants rely on stored water in a reservoir. This provides the flexibility to generate electricity on demand and reduces dependence on the variability of inflows. Very large reservoirs can retain months or even years of average inflows and can also provide flood protection and irrigation services.
  • Pumped storage plants (PSPs) use water that is pumped from a lower reservoir into an upper reservoir when electricity supply exceeds demand or can be generated at low cost. When demand exceeds instantaneous electricity generation and electricity has a high value, water is released to flow back from the upper reservoir through turbines to generate electricity. Pumped storage currently represents 99% of on-grid electricity storage.

Technology Roadmaps

The IEA has developed and regularly updates a series of global, low-carbon energy technology roadmaps which identify priority actions for governments, industry, financial partners and civil society that will advance technology development and uptake to achieve international climate change goals.

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Technology Roadmap: Hydropower

Published: 29 October 2012

Hydropower could double its contribution by 2050, reaching 2,000 GW of global capacity and over 7,000 TWh. This achievement, driven primarily by the quest of clean electricity, could prevent annual emissions of up to 3 billion tonnes of CO2 from fossil-fuel plants. The bulk of this growth would come from large plants in emerging economies and developing countries.

Hydroelectricity’s many advantages include reliability, proven technology, large storage capacity, and very low operating and maintenance costs. Hydropower is highly flexible, a precious asset for electricity network operators, especially given rapid expansion of variable generation from other renewable energy technologies such as wind power and photovoltaics. Many hydropower plants also provide flood control, irrigation, navigation and freshwater supply.

The technology roadmap for Hydropower details action needed from policy makers to allow hydroelectric production to double, and addresses necessary conditions, including resolving environmental issues and gaining public acceptance.

Technology Collaboration Programmes (TCPs)

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Hydropower TCP

The objective of the IEA TCP on Hydropower is to encourage awareness, knowledge and support for the sustainable use of water resources for the development and management of hydropower. This includes applying an interdisciplinary approach to hydropower research: increasing knowledge of a broad range of souses relating to hydropower, exploring areas of common interest among international organizations; disseminating balanced, unbiased information on hydropower; an encouraging hydropower development. There are eight Contracting Parties, including Brazil and China.

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About Technology Collaboration Programmes

The breadth and coverage of analytical expertise in the IEA Technology Collaboration Programmes (TCPs) are unique assets that underpin IEA efforts to support innovation for energy security, economic growth and environmental protection. The 38 TCPs operating today involve about 6 000 experts from government, industry and research organisations in more than 50 countries.

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