Why Are Dams Still Crucial for Energy Security and Sustainability?

In the 21st Century, great dams have metaphorically become what the pyramids were for ancient Egypt: monuments to human knowledge, the ability to leave a lasting mark, requiring decades of planning and construction and the involvement of thousands of workers.

Today, hydropower represents the world’s main renewable source: according to the International Energy Agency, over 60% of electricity generated from renewable sources comes from water, with an installed capacity exceeding 1,300 GW and an annual output covering about 16% of global electricity demand. From an environmental standpoint, every year hydroelectric power prevents billions of tons of CO₂ from entering the atmosphere, playing a decisive role in the fight against climate change.

In addition to their ability to reduce environmental impact, hydroelectric dams fuel industrial growth, ensure energy security and energy independence in developing countries; they can foster regional integration, and provide collateral benefits ranging from irrigation to flood control, inland navigation, and access to drinking water.

The new “pyramids of water” are often built in emerging countries, where energy demand is growing at a staggering pace. From Ethiopia to Brazil, Tajikistan to China, investing in dams means laying the foundations for an economy that is more resilient and less dependent on fossil fuels.

Projects like the Three Gorges Dam in China, or Ethiopia’s Grand Ethiopian Renaissance Dam (GERD) – the largest hydroelectric project in Africa built by Webuild not far from the Sudanese border – tell of hydroelectric power plant are able to support part of the entire nation’s energy needs.

In a world aiming to double the share of renewables by 2050, dams remain a pillar. More than other infrastructure, they embody the challenge of combining economic growth, energy security, and sustainability.

On the banks of the Blue Nile in Ethiopia, the GERD rises as one of the most imposing hydropower plants ever built in Africa.

The construction of this Ethiopian dam, carried out by the Webuild Group, involved over 25,000 people, with peaks of 10,000 workers, technicians, and engineers on site at the same time. The GERD, inaugurated on September 8 in the presence of Ethiopia’s prime minister and Webuild’s chief executive, Pietro Salini, will guarantee half of the country’s energy needs, while also enabling it to export hydroelectric power to Sudan, Djibouti, Kenya, and Tanzania.

While the Grand Ethiopian Renaissance Dam celebrates the end of its construction, work continues on the Omo River for the Koysha hydroelectric power plant. This Ethiopian dam project will have an installed capacity of 2,160 MW and integrate with other major hydroelectric infrastructures built along the same river (Gibe I, Gibe II, and Gibe III), all developed over the years by Webuild.

Together, these hydropower plants form a mosaic of projects aimed at turning Ethiopia into a regional hub for hydroelectric energy exports to neighbouring countries.

From Africa to Central Asia, another ambitious hydroelectric dam is reshaping the landscape of major infrastructure. The Rogun Hydropower Project in Tajikistan foresees the construction of a 335-meter-high rockfill dam, set to be the tallest dam in the world.

Under construction by Webuild, the Rogun dam is not only an extreme engineering project—it is located in the Pamirs, one of Central Asia’s main mountain ranges. It is also a promise of energy independence for a country that has long suffered from electricity shortages in the winter months.

Just like GERD, the project follows the same logic: turning water into development, linking energy production to an idea of national sovereignty and a sustainable future.

If there is one country that has turned dams into symbols of power, it is China.

The Three Gorges Dam on the Yangtze River, completed in 2012, with its 22,500 MW capacity, is the biggest dam in the world. It is not only a hydroelectric power machine but a work that has reshaped the landscape, river transport, and flood management on the Yangtze.

The Chinese dam is located in Hubei Province along the Yangtze and measures 2,335 metres in length and 185 meters in height. Its installed capacity enables it to generate up to 95 TWh of hydroelectric energy per year: enough to power cities the size of Beijing or Shanghai.

The reservoir that stretches behind it is about 600 kilometres long and has a capacity of over 39 billion cubic metres of water. This has made it possible not only to produce hydropower energy but also to improve navigation on the Yangtze, boosting trade links between eastern China and the hinterland, and to reduce the risk of devastating floods that have historically plagued the region.

The Three Gorges Dam is one of the most imposing “pyramids of water” of the 21st Century, capable of influencing not only China’s energy policy but also the global imagination of major infrastructures.

While Europe and the United States have slowed the construction of dams – focusing instead on maintaining existing ones and integrating them with other renewables – Africa and Asia remain the most dynamic arenas, where demographic and industrial growth drives energy demand.

These new dams are not just hydraulic infrastructures but also instruments of geopolitics, capable of reshaping regional power balances, creating dependencies or autonomy, and influencing environmental and social equilibriums. True game changers in the global chessboard of clean energy.