Rethinking hydropower’s role in the energy transition

By Colin Bowyer, Communications Manager - April 10, 2026

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As countries race to reduce carbon emissions and expand renewable energy, hydropower is once again at the center of global energy debates. A new international review published in Nature Sustainability examines the rapidly changing landscape of hydropower development and outlines opportunities to improve how large dam projects are planned and governed worldwide.

The review, co-authored by Bryan Tilt, an anthropologist in the College of Liberal Arts’ School of Language, Culture, and Society, gathered an interdisciplinary team of scholars from Europe, North America, Asia, and Latin America, to assess the social, environmental, and political dynamics shaping today’s global boom in hydropower construction, particularly in the Global South.

Currently, more than 3,700 hydropower dams producing over one megawatt of electricity are currently planned or under construction worldwide, primarily in emerging economies. While hydropower remains one of the world’s largest sources of low‑carbon electricity, the authors emphasize that large dams continue to cause significant ecological disruption, social displacement, governance failures, and uneven distribution of benefits. 

In 2000, the World Commission on Dams issued the most comprehensive and independent global review ever conducted on large dams. The key findings from survey data, case studies, and literature reviews highlighted widespread benefits in electricity produced and irrigated water supplied, but oftentimes with high social and environmental costs. The March 2026 report co-authored by Tilt and his colleagues is widely viewed as a follow up to the commission’s findings.

“Hydropower is a low carbon and reliable solution for climate mitigation,” said Tilt, whose research is focused on contemporary energy production in China and the U.S. “But the drawbacks of population displacement, environmental degradation are severe. There are pluses and minuses, heroes and villains; it’s not necessarily a straightforward story.” 

What’s different today? The conditions shaping hydropower development differ significantly from those of past dam‑building eras. Climate change motivations, the growth of private and Chinese-backed financing, stronger environmental justice movements, and new governance frameworks have reshaped the decision-making landscape.

The report’s central finding is that the success of hydropower's future depends on better governance. The outcomes are less dependent on engineering and more on how decisions are made, who is involved, and how trade-offs are managed. The evolving role of national governments, private investors, multilateral institutions, industry organizations, and environmental justice movements led the researchers to argue for more polycentric and participatory governance models, where decision-making authority is shared across multiple levels and actors. 

What’s been observed by the researchers is that decisions are made far from affected communities, rushed by political or financial pressure, and more often influenced by profit. Additionally, alternatives are frequently ignored by government officials, like complementing hydropower with solar and wind energy production, or upgrading or maintaining  current dams instead of building new ones.

Rushed oversight has also contributed to large dams still causing serious social and environmental harm, despite decades of research and guidelines. River fragmentation and loss of wildlife, deforestation and biodiversity decline, as well as displacement of Indigenous and rural communities continue to be consequential effects

“Overall, the world has gotten better at doing comprehensive social and environmental impact assessments of the entire river system rather than just the immediate area around the dam and downstream,” said Tilt. “But now that a vast majority of the dams are being built in emerging economies and at such speed, governments should still ask themselves how we can continue to build these large-scale dams more responsibly and sustainably for communities and ecosystems.”

One of the more striking findings from the report is that hydropower decisions are increasingly affecting international relations. “Hydropower governance is no longer dominated solely by national governments and engineers,” the authors note in the report. “Civil society, affected communities, and non‑state actors are increasingly shaping outcomes.”

About 70 percent of planned dams are located on rivers shared by multiple countries, whereby new dams can create tensions between countries. Weak international cooperation around shared rivers raises the risk of political conflict and downstream harm. 

The funding model for hydropower has also changed in the past 25 years. From what would be traditionally funded by international development organizations, presently, the China Development Bank and the Export-Import Bank of China is fueling hydropower’s growth. $41.2 billion have been invested abroad, most of which has been used for the construction of large dams in Africa, Asia, and Latin America. Also, with the support of the Chinese government, shareholder and state-owned Chinese companies have become global leaders in the construction of approximately 380 large dam projects in more than 70 countries, mostly in the Global South.

“15 years ago, the World Bank would be funding these projects,” explained Tilt. “Now through the Belt and Road Initiative, China is fueling hydropower’s growth outside of its borders. However, China's commitment to environmental impact assessments as well as resettlement and mitigation plans can differ depending on its contract with the state government. The same strings are being pulled as if it were the World Bank, but the players doing the pulling are different.”

The bottom line is that hydropower itself is not the problem, how it is planned and governed is. If current practices continue unchanged, new dams will likely deepen inequality, environmental damage, and conflict rather than support a fair energy transition. The solutions the authors put forward consist of: 

• planning hydroelectric projects at the river-basin scale  to holistically evaluate the river system and avoid environmental damage, displacement, and conflict;
• complementing hydropower with existing renewable energy systems alongside solar, wind, and energy storage; 
• improving governance by adopting a polycentric approach, where responsibility is shared among national and local governments, regulators, communities, and industry actors;
• and strengthening environmental and social impact assessments and including regional participation of Indigenous communities to enact a larger shared benefits approach. 

The authors stress that hydropower’s role in a low‑carbon future should be reconsidered. In some contexts, alternative renewable portfolios may deliver energy security with fewer social and environmental costs. Published at a time of renewed global investment in energy infrastructure, the review provides a comprehensive framework for policymakers, researchers, and practitioners seeking more equitable and sustainable approaches to hydropower development.