Dams are among the largest human structures, often built with millions of tonnes of dirt, rock, concrete, and other materials to span rivers or sequester lake water. They serve various purposes, such as storing water for consumption and irrigation, generating hydroelectric power, protecting against peak flood discharge, and facilitating water navigation and recreation.
Documenting the world’s largest dams is complex, as “largest” can refer to height, overall volume, reservoir size, or electric power capacity.
The largest dams in the world are truly immense, often exceeding 240 metres (about 787 feet) in height and 60 million cubic metres (about 2.1 billion cubic feet) in volume. The volumes of the largest water reservoirs held back by dams range from some 60 billion cubic metres (2.1 trillion cubic feet) to nearly 3 trillion cubic metres (106 trillion cubic feet). The largest hydroelectric dams generate more than 10,000 megawatts of electricity.
Hydroelectric power, electricity produced from generators driven by turbines that convert the potential energy of falling or fast-flowing water into mechanical energy. In the early 21st century, hydroelectric power was the most widely utilized form of renewable energy; in 2019 it accounted for more than 18 percent of the world’s total power generation capacity.
In hydroelectric power generation, water is stored at a higher elevation and flows downward through large pipes or tunnels (penstocks) to a lower elevation, known as the head. As the water falls, it rotates turbines, which drive generators that convert mechanical energy into electricity. Transformers then change the alternating voltage from the generators to a higher voltage for long-distance transmission. The powerhouse is the structure housing the turbines and generators, where the penstocks feed in.
Hydroelectric plants are typically built in dams that impound rivers, raising the water level and creating a feasible head. The potential power derived from water volume is directly proportional to the working head; thus, a high-head installation needs less water than a low-head one for equal power output. In some dams, the powerhouse is on one side of the dam, with part of the dam serving as a spillway for excess water during floods. When a river flows through a narrow gorge, the powerhouse may be located within the dam itself.
The largest dams in the world are truly immense, often exceeding 240 metres (about 787 feet) in height and 60 million cubic metres (about 2.1 billion cubic feet) in volume. The volumes of the largest water reservoirs held back by dams range from some 60 billion cubic metres (2.1 trillion cubic feet) to nearly 3 trillion cubic metres (106 trillion cubic feet). The largest hydroelectric dams generate more than 10,000 megawatts of electricity.
Hydroelectric power, electricity produced from generators driven by turbines that convert the potential energy of falling or fast-flowing water into mechanical energy. In the early 21st century, hydroelectric power was the most widely utilized form of renewable energy; in 2019 it accounted for more than 18 percent of the world’s total power generation capacity.
In hydroelectric power generation, water is stored at a higher elevation and flows downward through large pipes or tunnels (penstocks) to a lower elevation, known as the head. As the water falls, it rotates turbines, which drive generators that convert mechanical energy into electricity. Transformers then change the alternating voltage from the generators to a higher voltage for long-distance transmission. The powerhouse is the structure housing the turbines and generators, where the penstocks feed in.
Hydroelectric plants are typically built in dams that impound rivers, raising the water level and creating a feasible head. The potential power derived from water volume is directly proportional to the working head; thus, a high-head installation needs less water than a low-head one for equal power output. In some dams, the powerhouse is on one side of the dam, with part of the dam serving as a spillway for excess water during floods. When a river flows through a narrow gorge, the powerhouse may be located within the dam itself.
In hydroelectric power generation, water is stored at a higher elevation and flows downward through large pipes or tunnels (penstocks) to a lower elevation, known as the head. As the water falls, it causes turbines to rotate, driving generators that convert mechanical energy into electricity. Transformers then convert the alternating voltage from the generators to a higher voltage for long-distance transmission. The structure housing the turbines and generators is called the powerhouse.
Hydroelectric plants are usually built in dams that impound rivers, raising the water level and creating a feasible head. The potential power from water volume is directly proportional to the working head; thus, a high-head installation requires less water than a low-head one for equal power output. In some dams, the powerhouse is on one side, with part of the dam serving as a spillway for excess water during floods. Where a river flows through a narrow gorge, the powerhouse may be located within the dam itself.
Most communities experience varying electric power demand throughout the day. To balance the load on generators, pumped-storage hydroelectric stations are built. During off-peak periods, excess power is used to operate the generator as a motor, pumping water into an elevated reservoir. During peak demand, this water flows down again through the turbine to generate electricity. Pumped-storage systems are efficient and provide an economical way to meet peak loads.
In certain coastal areas, like the Rance River estuary in Brittany, France, hydroelectric power plants exploit the rise and fall of tides. When the tide comes in, water is stored in reservoirs, and at low tide, it’s released to drive hydraulic turbines and their electric generators.
Hydroelectric plants are usually built in dams that impound rivers, raising the water level and creating a feasible head. The potential power from water volume is directly proportional to the working head; thus, a high-head installation requires less water than a low-head one for equal power output. In some dams, the powerhouse is on one side, with part of the dam serving as a spillway for excess water during floods. Where a river flows through a narrow gorge, the powerhouse may be located within the dam itself.
Most communities experience varying electric power demand throughout the day. To balance the load on generators, pumped-storage hydroelectric stations are built. During off-peak periods, excess power is used to operate the generator as a motor, pumping water into an elevated reservoir. During peak demand, this water flows down again through the turbine to generate electricity. Pumped-storage systems are efficient and provide an economical way to meet peak loads.
In certain coastal areas, like the Rance River estuary in Brittany, France, hydroelectric power plants exploit the rise and fall of tides. When the tide comes in, water is stored in reservoirs, and at low tide, it’s released to drive hydraulic turbines and their electric generators.
Biggest dams in water volume
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Biggest dams in landfill
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