The Three Gorges Dam in China; the hydroelectric dam is the world's largest power station by installed capacity.
A water piston from the Nongshu by Wang Zhen (fl. 1290–1333)
Saint Anthony Falls, United States; hydropower was used here to mill flour.
Directly water-powered ore mill, late nineteenth century
Benoît Fourneyron, the French engineer who developed the first hydropower turbine
A shishi-odoshi powered by falling water breaks the quietness of a Japanese garden with the sound of a bamboo rocker arm hitting a rock.
A conventional dammed-hydro facility (hydroelectric dam) is the most common type of hydroelectric power generation.
Chief Joseph Dam near Bridgeport, Washington, is a major run-of-the-river station without a sizeable reservoir.
Micro hydro in Northwest Vietnam
The upper reservoir and dam of the Ffestiniog Pumped Storage Scheme in Wales. The lower power station can generate 360 MW of electricity.

Use of falling or fast-running water to produce electricity or to power machines.

- Hydropower

500 related topics


Renewable energy

Energy that is collected from renewable resources that are naturally replenished on a human timescale.

Renewable energy capacity additions in 2020 expanded by more than 45% from 2019, including 90% more new wind power (green) and a 23% expansion of new solar photovoltaic installations (yellow).
Coal, oil, and natural gas remain the primary global energy sources even as renewables have begun rapidly increasing.
PlanetSolar, the world's largest solar-powered boat and the first ever solar electric vehicle to circumnavigate the globe (in 2012)
A bus fueled by biodiesel
The Three Gorges Dam on the Yangtze River in China
Wind energy generation by region over time.
Global map of wind power density potential.
Satellite image of the Bhadla Solar Park in India, it is the largest Solar Park in the world
Global map of horizontal irradiation.
Steam rising from the Nesjavellir Geothermal Power Station in Iceland
Enhanced geothermal system (see [[:File:EGS diagram.svg|file description]] for details)
Rance Tidal Power Station, France
Estimated power demand over a week in 2012 and 2020, Germany, showing the need for dispatchable generation rather than baseload generation in the grid.
A comparison of prices over time for energy from nuclear fission and from other sources. Over the presented time, thousands of wind turbines and similar were built on assembly lines in mass production resulting in an economy of scale.
In 2020, renewables overtook fossil fuels as the European Union's main source of electricity for the first time.
Comparing worldwide energy use, the growth of renewable energy is shown by the green line
Worldwide growth of wind capacity (1996–2018)
Four offshore wind farms are in the Thames Estuary area: Kentish Flats, Gunfleet Sands, Thanet and London Array. The latter is the largest in the world as of April 2013.
Ivanpah solar plant in the Mojave Desert, California, United States
Solar towers of the PS10 and PS20 solar thermal plants in Spain
Solar panels at the 550 MW Topaz Solar Farm
Brazil produces bioethanol made from sugarcane available throughout the country. A typical gas station with dual fuel service is marked "A" for alcohol (ethanol) and "G" for gasoline.
Geothermal plant at The Geysers, California, US
Most respondents to a climate survey conducted in 2021-2022 by the European Investment Bank say countries should back renewable energy to fight climate change.
A concept of a super grid.
Burbo, NW-England
Sunrise at the Fenton Wind Farm in Minnesota, US
The CSP-station Andasol in Andalusia, Spain
Three Gorges Dam and Gezhouba Dam, China
Shop selling PV panels in Ouagadougou, Burkina Faso
Stump harvesting increases recovery of biomass from forests
A small, roof-top mounted PV system in Bonn, Germany
The community-owned Westmill Solar Park in South East England
Komekurayama photovoltaic power station in Kofu, Japan
Krafla, a geothermal power station in Iceland

In 2021, Norway, known for its production of hydroelectricity, consumed hydro energy worth 45% of its total energy supply.


Natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river.

The Amazon River (dark blue) and the rivers which flow into it (medium blue).
The start of a mountain stream.
Melting toe of Athabasca Glacier, Jasper National Park, Alberta, Canada
The Colorado River at Horseshoe Bend, Arizona
The Porvoo River (Porvoonjoki) in the medieval town of Porvoo, Finland
Nile River delta, as seen from Earth orbit. The Nile is an example of a wave-dominated delta that has the classic Greek letter delta (Δ) shape after which river deltas were named.
A radar image of a 400 km river of methane and ethane near the north pole of Saturn's moon Titan
River meandering course
Flash flooding caused by a large amount of rain falling in a short amount of time
The mouth of the River Seaton in Cornwall after heavy rain caused flooding and significant erosion of the beach.
Frozen river in Alaska
Leisure activities on the River Avon at Avon Valley Country Park, Keynsham, United Kingdom. A boat giving trips to the public passes a moored private boat.
Watermill in Belgium.
River bank repair

Most of the major cities of the world are situated on the banks of rivers, as they are, or were, used as a source of water, for obtaining food, for transport, as borders, as a defensive measure, as a source of hydropower to drive machinery, for bathing, and as a means of disposing of waste.

Trip hammer

Massive powered hammer.

A 1960s trip hammer placed at Trattenbach village, Lower Austria
The same trip hammer in operation, shaping a folding knife at the strike area
A water powered trip hammer from the Nong Shu by Wang Zhen (fl. 1290–1333)
Hydrodynamic powered trip hammer set, illustration from the Tiangong Kaiwu encyclopedia of 1637, written by Song Yingxing (1587–1666)
The regular indentations on the Carreg Pumsaint and similar mortar blocks are believed to stem from mechanically operated trip hammers.
Roman stone anvil for a stamp battery
Water-powered ore crusher by Georgius Agricola
Water-powered hammers at Abbeydale Industrial Hamlet

Historically, trip hammers were often powered hydraulically by a water wheel.


Watermill of Braine-le-Château, Belgium (12th century)
Interior of the Lyme Regis watermill, UK (14th century)
Model of a Roman water-powered grain-mill described by Vitruvius. The millstone (upper floor) is powered by an undershot waterwheel by the way of a gear mechanism (lower floor)
Scheme of the Roman Hierapolis sawmill, the earliest known machine to incorporate a crank and connecting rod mechanism.
Roman turbine mill at Chemtou, Tunisia. The tangential water inflow of the millrace made the horizontal wheel in the shaft turn like a true turbine, the earliest known.
Medieval watermill
German ship mills on the Rhine, around 1411
A Northern Song era (960–1127) water-powered mill for dehusking grain with a horizontal wheel
An Afghan water mill photographed during the Second Anglo-Afghan War (1878-1880). The rectangular water mill has a thatched roof and traditional design with a small horizontal mill-house built of stone or perhaps mud bricks
A watermill in Tapolca, Veszprem County, Hungary
Roblin's Mill, a watermill, at Black Creek Pioneer Village in Toronto, Ontario, Canada
Watermills on the Pliva in Jajce, Bosnia and Herzegovina
The interior of a functional watermill at Weald and Downland Open Air Museum
Mulino Meraviglia in San Vittore Olona, Italy, along Olona river
Dalgarven Mill, Ayrshire, United Kingdom
A breastshot waterwheel at Dalgarven Mill, United Kingdom
Watermill in Kuusamo (Finland)
Watermill in Jahodná (Slovakia)
Watermill in Caldas Novas, Brazil
Former watermill in Kohila, Estonia
Undershot water wheel, applied for watermilling since the 1st century BC
Overshot water wheel, applied for watermilling since the 1st century BC
Breastshot water wheel, applied for watermilling since the 3rd century AD<ref name="Wikander 2000, 375"/>
Pitchback water wheel, often used to increase the power generated by a breastshot wheel<ref name="Yorke">{{cite book|last=Yorke|first=Stan|title=The Industrial Revolution explained|publisher=Countryside Books|location=Newbury, Berks|year=2005|pages=20–31|isbn=978-1-85306-935-2}}</ref>

A watermill or water mill is a mill that uses hydropower.


Facility where logs are cut into lumber.

Sawing logs into finished lumber with a basic "portable" sawmill
An American sawmill,
Early 20th-century sawmill, maintained at Jerome, Arizona.
Scheme of the water-driven sawmill at Hierapolis, Asia Minor. The 3rd-century mill incorporated a crank and connecting rod mechanism.
Illustration of a human-powered sawmill with a gang-saw, published in 1582.
"De Salamander" a wind driven sawmill in Leidschendam, The Netherlands. Built in 1792, it was used until 1953, when it fell into disrepair. It was fully restored in 1989.
A sawmill in the interior of Australia,
Modern reconstruction Sutter's mill in California, where gold was first found in 1848.
A sawmill of Naistenlahti in Tampere, Finland, 1890s
Oregon Mill using energy efficient ponding to move logs
Inside a modern sawmill equipped with laser-guided technology
Wood traveling on sawmill machinery
Sawdust waste from the mill
A sawmill in Armata, on mount Smolikas, Epirus, Greece.
A preserved water powered sawmill, Norfolk, England.
Making planks from logs
Sawmill in Luchon, France, near 1840 by Eugène de Malbos
Sawmill workers posing with saw blades, Rainy River District, between 1900-1909.
Sawmill with the floating logs in Kotka, Finland.
Logs at sawmill at Manitoulin Island [190-?]

By the 11th century, hydropowered sawmills were in widespread use in the medieval Islamic world, from Islamic Spain and North Africa in the west to Central Asia in the east.


Barrier that stops or restricts the flow of surface water or underground streams.

Glen Canyon Dam on the Colorado River, Arizona, USA
Lake Vyrnwy Dam, Wales, finished in 1888
Karapuzha Dam, an earthen dam in the Indian state of Kerala
Imatrankoski Dam on the Vuoksi River in Imatra, Finland
Small dam near Groningen, Netherlands
Afsluitdijk with the Wadden Sea (a part of the North Sea) on the left and the IJsselmeer on the right in the Netherlands
The Roman dam at Cornalvo in Spain has been in use for almost two millennia.
Remains of the Band-e Kaisar dam, built by the Romans in the 3rd century AD
An engraving of the Rideau Canal locks at Bytown
Masonry arch wall, Parramatta, New South Wales, the first engineered dam built in Australia
The Hoover Dam by Ansel Adams, 1942
Gordon Dam, Tasmania, is an arch dam.
Daniel-Johnson Dam, Quebec, is a multiple-arch buttress dam.
The Grand Coulee Dam is an example of a solid gravity dam.
The Hoover Dam is an example of an arch-gravity dam.
The Koshi Barrage of Nepal
Gathright Dam in Virginia is a rock-fill embankment dam.
Redridge Steel Dam, built 1905, Michigan
A timber crib dam in Michigan, 1978
A cofferdam during the construction of locks at the Montgomery Point Lock and Dam
Hydraulic turbine and electric generator
Hydroelectric dam in cross section
Spillway on Llyn Brianne dam, Wales, soon after first fill
The discharge of Takato Dam
Wood and garbage accumulation due to a dam
South Fork Dam failure and resulting flood that destroyed Johnstown in Pennsylvania in 1889
International special sign for works and installations containing dangerous forces

Hydropower is often used in conjunction with dams to generate electricity.

Richard Arkwright

English inventor and a leading entrepreneur during the early Industrial Revolution.

Sir Richard Arkwright, oil on canvas, by Mather Brown, 1790. New Britain Museum of American Art, Connecticut.
Susannah Arkwright, Mrs Charles Hurt (1762–1835), and her daughter Mary Anne (painting by Joseph Wright of Derby)
Arkwright's mill at Cromford
Masson Mill on the river Derwent, and Arkwright's house Willersley Castle, completed only after his death.
Blue plaque marking the occupancy by Arkwright in Adam Street, London

He is credited as the driving force behind the development of the spinning frame, known as the water frame after it was adapted to use water power; and he patented a rotary carding engine to convert raw cotton to 'cotton lap' prior to spinning.


The Three Gorges Dam in Central China is the world's largest power–producing facility of any kind.
Museum Hydroelectric power plant ″Under the Town″ in Serbia, built in 1900.
The Warwick Castle water-powered generator house, used for the generation of electricity for the castle from 1894 until 1940
A micro-hydro facility in Vietnam
Pico hydroelectricity in Mondulkiri, Cambodia
Measurement of the tailrace and forebay rates at the Limestone Generating Station in Manitoba, Canada.
The Ffestiniog Power Station can generate 360 MW of electricity within 60 seconds of the demand arising.
Merowe Dam in Sudan. Hydroelectric power stations that use dams submerge large areas of land due to the requirement of a reservoir. These changes to land color or albedo, alongside certain projects that concurrently submerge rainforests, can in these specific cases result in the global warming impact, or equivalent life-cycle greenhouse gases of hydroelectricity projects, to potentially exceed that of coal power stations.
The Hoover Dam in the United States is a large conventional dammed-hydro facility, with an installed capacity of 2,080 MW.
World renewable energy share (2008)
Trends in the top five hydroelectricity-producing countries
Share of electricity production from hydropower, 2020

Hydroelectricity, or hydroelectric power, is electricity produced from hydropower.

Industrial Revolution

The transition to new manufacturing processes in Great Britain, continental Europe, and the United States, in the period from about 1760 to sometime between 1820 and 1840.

A Roberts loom in a weaving shed in 1835.
Handloom weaving in 1747, from William Hogarth's Industry and Idleness
European colonial empires at the start of the Industrial Revolution, superimposed upon modern political boundaries.
A weaver in Nürnberg, c. 1524
A model of the spinning jenny in a museum in Wuppertal. Invented by James Hargreaves in 1764, the spinning jenny was one of the innovations that started the revolution.
The only surviving example of a spinning mule built by the inventor Samuel Crompton. The mule produced high-quality thread with minimal labour. Bolton Museum, Greater Manchester
The interior of Marshall's Temple Works in Leeds, West Yorkshire
Lombe's Mill site today, rebuilt as Derby Silk Mill
The reverberatory furnace could produce cast iron using mined coal. The burning coal remained separate from the iron and so did not contaminate the iron with impurities like sulfur and silica. This opened the way to increased iron production.
The Iron Bridge, Shropshire, England, the world's first bridge constructed of iron opened in 1781.
Horizontal (lower) and vertical (upper) cross-sections of a single puddling furnace. A. Fireplace grate; B. Firebricks; C. Cross binders; D. Fireplace; E. Work door; F. Hearth; G. Cast iron retaining plates; H. Bridge wall
A Watt steam engine. James Watt transformed the steam engine from a reciprocating motion that was used for pumping to a rotating motion suited to industrial applications. Watt and others significantly improved the efficiency of the steam engine.
Newcomen's steam-powered atmospheric engine was the first practical piston steam engine. Subsequent steam engines were to power the Industrial Revolution.
Maudslay's famous early screw-cutting lathes of circa 1797 and 1800
The Middletown milling machine of c. 1818, associated with Robert Johnson and Simeon North
The Thames Tunnel (opened 1843).
Cement was used in the world's first underwater tunnel.
The Crystal Palace housed the Great Exhibition of 1851
The Bridgewater Canal, famous because of its commercial success, crossing the Manchester Ship Canal, one of the last canals to be built.
Construction of the first macadam road in the United States (1823). In the foreground, workers are breaking stones "so as not to exceed 6 ounces in weight or to pass a two-inch ring".
Painting depicting the opening of the Liverpool and Manchester Railway in 1830, the first inter-city railway in the world and which spawned Railway Mania due to its success.
Wedgwood tea and coffee service
Winchester High Street, 1853. The number of High Streets (the primary street for retail in Britain) in towns and cities rapidly grew in the 18th century.
The Black Country in England, west of Birmingham
Manchester, England ("Cottonopolis"), pictured in 1840, showing the mass of factory chimneys
A young "drawer" pulling a coal tub along a mine gallery. In Britain, laws passed in 1842 and 1844 improved mine working conditions.
Luddites smashing a power loom in 1812
Levels of air pollution rose during the Industrial Revolution, sparking the first modern environmental laws to be passed in the mid-19th century.
Slater's Mill in Pawtucket, Rhode Island.
Sächsische Maschinenfabrik in Chemnitz, Germany, 1868
Sir Henry Bessemer's Bessemer converter, the most important technique for making steel from the 1850s to the 1950s. Located in Sheffield (Steel City)
Regional GDP per capita changed very little for most of human history before the Industrial Revolution.
Interior of the London Coal Exchange, c. 1808.
European 17th-century colonial expansion, international trade, and creation of financial markets produced a new legal and financial environment, one which supported and enabled 18th-century industrial growth.
As the Industrial Revolution developed British manufactured output surged ahead of other economies.
William Bell Scott Iron and Coal, 1855–60
William and Mary Presenting the Cap of Liberty to Europe, 1716, Sir James Thornhill. Enthroned in heaven with the Virtues behind them are the royals William III and Mary II who had taken the throne after the Glorious Revolution and signed the English Bill of Rights of 1689. William tramples on arbitrary power and hands the red cap of liberty to Europe where, unlike Britain, absolute monarchy stayed the normal form of power execution. Below William is the French king Louis XIV.
A Philosopher Lecturing on the Orrery by Joseph Wright of Derby (c. 1766). Informal philosophical societies spread scientific advances
A primitive lifestyle living outside the Industrial Revolution
A dog forced to eat trash due to pollution, the Industrial Revolution has forced animals into harsh environments most are unable to survive in, leading to starvation and eventual extinction

This transition included going from hand production methods to machines, new chemical manufacturing and iron production processes, the increasing use of steam power and water power, the development of machine tools and the rise of the mechanized factory system.

Niagara Falls

Group of three waterfalls at the southern end of Niagara Gorge, spanning the border between the province of Ontario in Canada and the state of New York in the United States.

Canadian Horseshoe Falls at right
American Falls (large waterfall center-left) and Bridal Veil Falls (right)
Niagara Escarpment (in red). Niagara Falls is center-right between Lake Ontario and Lake Erie.
Damage from wind and ice on Goat Island, 1903
American Falls diverted during erosion control efforts in 1969
Louis Hennepin is depicted in front of the falls in this 1698 print.
Horseshoe Falls, 1869
American Falls frozen over with people on the ice, 1911
Aerial photograph of Niagara Falls, 1931
Hand-colored lithograph of the (double-decked) Niagara Suspension Bridge, c. 1856
Niagara Cantilever Bridge, c. 1895
The Rainbow Bridge, the first bridge downstream from the falls
New York side of Niagara Gorge, c. 1901
Ten 5,000 HP Westinghouse generators at Edward Dean Adams Power Plant
Robert Moses Niagara Power Plant in Lewiston, New York
The Welland Canal connects Lake Ontario and Lake Erie through a series of eight locks, allowing ships to bypass the 51 m high Niagara Falls
Bobby Leach and his barrel after his trip over Niagara Falls, (1911 photo)
Annie Edson Taylor posing with her wooden barrel (1901)
Charles Stephens in his barrel, prior to his fatal July 1920 attempt
Blondin carrying his manager, Harry Colcord, on a tightrope
Advertising broadside for trip to Niagara Falls from Massachusetts, 1895
Prospect Point Observation Tower (also known as the Niagara Falls Observation Tower)
Skylon Tower as seen from a helicopter on the Canadian side
The opening title from the theatrical trailer of the 1953 film Niagara.
José María Heredia y Heredia plaque at Table Rock
A General View of the Falls of Niagara by Alvan Fisher, 1820
Distant View of Niagara Falls by Thomas Cole, 1830
Niagara Fälle. Les chûtes du Niagara. Niagara Falls by Karl Bodmer, circa 1832
Voute sous la Chute du Niagara – Niagara Falls, circa 1841
Niagara by Frederic Edwin Church, 1857
Underneath Niagara Falls by Ferdinand Richardt, 1862
Niagara by Louis Rémy Mignot, circa 1866
Falls of Niagara from Below by Albert Bierstadt, 1869
Niagara Falls by William Morris Hunt, 1878
Niagara Falls, circa 1880

Augustus and Peter Porter purchased this area and all of American Falls in 1805 from the New York state government, and enlarged the original canal to provide hydraulic power for their gristmill and tannery.