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This video expresses how important having hydro power as a contribution to the energy consumption is.

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The importance of water is one of the most pivotal portions to life, proving that supplying people with a safe energy resource, as well as reserve of this precious commodity is at the up most importance.

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This video expresses that construction is a highly optimistic industry, always growing and developing, proving it is a good career field to persue.

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Construction contractors and equipment distributors continue to show strong optimism about an increase in local construction activity in 2016. The Optimism Quotient- this survey's primary benchmark for measuring contractor and equipment distributor sentiment on local nonresidential construction activity- is 108 for 2016.

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Expressed in this video is the newest and most innovative equipment in the heavy civil construction industry.

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This video is of the largest dam in the world, fed off the Yanzy River in China. Giving a entry description of this dam and the process of completing this project.

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World Amazing Technology Emergency Water Power Dam Discharge USA

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Largest Dams in The World http://largest-dams-1.blogspot.com

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This video illustrates the fast tracked project of constructing a resistor.

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Principal Contractor: Cheetham Hill Construction Ltd Client: United Utilities Scope: Design and build project to discontinue Hurst Impounding Reservoir, a Category A reservoir and decommission it from the scope of the Reservoirs Act.

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Construction the Hoover Dam proved to be a difficult process, one that needed to have constant problem solving, this field of work never seems to be anything less than surprising.

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In this video, one can learn two different forums of hydroelectric; the Dam, and the Run of river. It also suggests why one would be chosen over the other.

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This video gives a great description oh just how a hydroelectric power works, showing the way this renewable resource creates electric power.

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The New Croton Dam supplies New York City with 30% of there potable water. This video shows how when reservoirs are constructed with care and consideration, they can be a beautiful addition to the area as well as a useful resource.

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Croton Dam Abandoned Hydro Electric Dam Remains

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The New Croton Dam (Part 3 - Water for New York City)

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Greetings, folks! I thought I'd cap off the recent series about New York City's water by taking a quick field trip up to the New Croton Dam. I was originally hoping to find some piece of the Old Dam but it turns out it's under 34 feet of water at the bottom of the New Croton Reservoir.

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Granite construction is based out of California and revolves around sustainability and leadership in the construction industry.

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New Line Structures is a company based out of New York, they deal with projects revolving around the New York NY area.

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Blattner Energy, a company based out of Minnesota revolving around windmill constriction.

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Wind

Blattner has installed more than 35,000 megawatts of wind power across North America, including the five single-largest projects in the United States. Our success in utility-scale wind farm construction stems from a strong history of delivering A BETTER CONSTRUCTION EXPERIENCE™ by responding to client needs, delivering on aggressive project schedules, and ensuring the highest levels of safety, quality, and overall client satisfaction.

Blattner's wind capabilities include:

Pre-Construction
* Surveying
* Permitting procurement
* Land-use optimization
* Geotechnical investigation

Engineering and Design
* Civil
* Electrical
* Geotechnical

Material Procurement
* Storage
* Transportation, receiving and inspection
* Inventory control and onsite logistics

Construction
* Site civil work, ROW, erosion control, and reclamation
* Foundation installation
* Turbine installation and mechanical completion
* Electrical collection systems
* Transmission line installation
* Substation construction
* Communication network installations
* Testing and commissioning
* O&M building construction
Construction Management
Unrivaled Self-Performance
Blattner differs from the typical renewable energy construction contractor by executing aspects of wind farm construction on our client's behalf.

Our proven project management skill set and self-performance capabilities allow us to understand the critical components of every project.

We effectively communicate the impact of decisions, foresee and mitigate any potential problems, and ensure control over safety, quality, schedule, and productivity.

Electrical Competencies
Our electrical expertise differentiates us from other utility-scale wind-farm construction contractors. We've built a core of diverse utility veterans and experienced electrical personnel. Our team consists of in-house electrical engineering resources, task-specific engineers, and industry-proven electrical subcontractors. We believe that early integration of the wind farm design, grid interconnection, and electrical system is paramount and provides significant value to our clients. We provide assurance for renewable energy construction through:

Design review and optimization

One line development

Reliability planning for transmission and generation interconnects

Power quality considerations

Safety provisions in design, construction, and operations

Low voltage ride through modeling

Economic analysis of input parameters for accurate cost of fixed and variable electric losses

Post-commissioning performance assurance

Transmission grid integration

Landowner Relations
While some contractors view the community as a potential obstacle to success, Blattner proactively cultivates strong landowner and community relationships on behalf of our clients.

Blattner directly addresses landowner questions and concerns.

We organize landowner information meetings and hold local workforce/vendor fairs.

We form positive community relationships, helping to ensure Blattner projects progress with fewer delays and set the stage for our clients' continued success in the area.

Environmental Stewardship
Blattner recognizes the importance of identifying and preserving local wildlife, sensitive habitats, and culturally significant resources in and around project sites. We collaborate with our clients to ensure we work within the guidelines of specified regulatory bodies on each project site, and we comply with all local, county, state, and federal regulations.

Other Markets

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Blattner has installed more than 35,000 megawatts of wind power across North America, including the five single-largest projects in the United States. Our success in utility-scale wind farm construction stems from a strong history of delivering A BETTER CONSTRUCTION EXPERIENCE™ by responding to client needs, delivering on aggressive project schedules, and ensuring the highest levels of safety, quality, and overall client satisfaction.

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Crowder Heavy Foundations is based out of North Carolina, specializing in heavy foundations and other heavy cavil construction practices.

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McCarthy constriction is a company that deals with heavy cavil and transportation. This company headquarters are based out of Dallas Texas

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Civil Construction & Heavy Civil Construction | McCarthy

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Discover McCarthy's commitment to quality in civil construction-from transportation projects like highways and light rail to other heavy civil construction.

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Layne is based out of Texas, specializing in drilling and other water management operations.

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Layne Christensen provides drilling and related services

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Mortenson is a company base in Massachusetts that deals with heavy civil projects on a large scale.

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ASI is a company based out of CO, revolving around
Dam and Water Resource Construction.

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ASI Construction LLC | ASI Construction LLC

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ASI is a self-performing heavy-civil contractor specializing in the construction and rehabilitation of dams, spillways, and major water resource projects.

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Barnard Construction a company out of Montana, dealing with mostly heavy civil construction projects.

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That's what we do at Barnard. Whether we're raising a dam in Alaska, constructing a reservoir in Florida, tunneling under downtown San Francisco, redirecting a river while building a complex hydropower plant in northern Manitoba, or strengthening and improving the integrity of a natural gas pipeline in a Sacramento suburb, our people arrive at our projects with a determination to do the best for their communities and be the best in the industry.

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The company i have worked with for the past 2 years does work with the Pike Company, a Rochester based company that has possibility of future employment to me.

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The Pike Company places a rigorous focus on project management, work quality, and client satisfaction. Pike's long list of projects and repeat customers demonstrates our success at maintaining long-term relationships, exceeding expectations, and completing an array of challenging jobs on schedule and within budget.

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The biggest hydro plant in the United States is located at the Grand Coulee Dam on the Columbia River in northern Washington. More than 70 percent of the electricity made in Washington State is produced by hydroelectric facilities. Proving that hydropower can create energy on a large scale.

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Hydropower is electricity generated using the energy of moving water. Rain or melted snow, usually originating in hills and mountains, create streams and rivers that eventually run to the ocean. The energy of that moving water can be substantial, as anyone who has been whitewater rafting knows.

Humans have been taking advantage of this source of energy for centuries. Farmers since the ancient Greeks have used water wheels to grind wheat into flour. Placed in a river, a water wheel picks up flowing water in buckets located around the wheel. The kinetic energy of the flowing river turns the wheel and is converted into mechanical energy that runs the mill.

In the late 19th century, hydropower became a source for generating electricity. The first hydroelectric power plant was built at Niagara Falls in 1879. In 1881, street lamps in the city of Niagara Falls were powered by hydropower. In 1882, the world's first hydroelectric power plant began operating in the United States in Appleton, Wisconsin.

How it Works

A typical hydro plant is a system with three parts: an electric plant where the electricity is produced, a dam that can be opened or closed to control water flow, and a reservoir where water can be stored. The water behind the dam flows through an intake and pushes against blades in a turbine, causing them to turn. The turbine spins a generator to produce electricity. The amount of electricity that can be generated depends on how far the water drops and how much water moves through the system. The electricity can be transported through long-distance electric lines to homes, factories, and businesses.

Where It's Used

Hydroelectric power provides almost one-fifth of the world's electricity. China, Canada, Brazil, the United States, and Russia were the five largest producers of hydropower in 2004. One of the world's largest hydro plants is at Three Gorges on China's Yangtze River. The dam is 1.4 miles (2.3 kilometers) wide and 607 feet (185 meters) high.

The biggest hydro plant in the United States is located at the Grand Coulee Dam on the Columbia River in northern Washington. More than 70 percent of the electricity made in Washington State is produced by hydroelectric facilities.

Hydropower is the cheapest way to generate electricity today. That's because once a dam has been built and the equipment installed, the energy source-flowing water-is free. It's a clean fuel source that is renewable yearly by snow and rainfall. Hydropower is also readily available; engineers can control the flow of water through the turbines to produce electricity on demand. In addition, reservoirs may offer recreational opportunities, such as swimming and boating.

But damming rivers may destroy or disrupt wildlife and other natural resources. Some fish, like salmon, may be prevented from swimming upstream to spawn. Technologies like fish ladders help salmon go up over dams and enter upstream spawning areas, but the presence of hydroelectric dams changes their migration patterns and hurts fish populations. Hydropower plants can also cause low dissolved oxygen levels in the water, which is harmful to river habitats.

Some researchers believe the strain dams impose on the environment make this method of energy production more trouble than it's worth. A study in the journal BioSciences found that the reservoirs created by dams pollute methane, a greenhouse gas, into the atmosphere as a result of the breakdown of organisms in now stagnant pools of water.

In addition to environmental concerns, dams also pose a strain on the communities around them. The Three Gorges dam on China's Yangtze River displaced an estimated 1.3 million people and flooded thousands of villages.

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hydro hydropower hydroelectricity alternative energy turbines irrigation tidal wave waterwheels electric power generation dams fossil fuels

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Hydropower is electricity generated using the energy of moving water. Rain or melted snow, usually originating in hills and mountains, create streams and rivers that eventually run to the ocean. The energy of that moving water can be substantial, as anyone who has been whitewater rafting knows.

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This article describes how hydropower works and why it is a green energy resource.

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This article explains that employment among construction laborers is expected to grow at a rate of about 21 percent. showing that construction in a healthy industry to peruse.

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According to the National Association of Home Builders, 8.7 million Americans worked in construction as of 2010. Construction workers build residential, commercial and industrial buildings, as well as the infrastructure that makes modern society possible, from roads and bridges to dams and mines. A career as a ...

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This article explains different types of hydro-powered turbines and how the achive creating energy.

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The common processes behind why wind energy is effective and the common pratices to achive energy.

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Wind is a form of solar energy caused by a combination of three concurrent events:

1. The sun unevenly heating the atmosphere

2. Irregularities of the earth's surface

3. The rotation of the earth.

Wind flow patterns and speeds vary greatly across the United States and are modified by bodies of water, vegetation, and differences in terrain. Humans use this wind flow, or motion energy, for many purposes: sailing, flying a kite, and even generating electricity.

The terms "wind energy" and "wind power" both describe the process by which the wind is used to generate mechanical power or electricity. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity.

A wind turbine turns wind energy into electricity using the aerodynamic force from the rotor blades, which work like an airplane wing or helicopter rotor blade. When wind flows across the blade, the air pressure on one side of the blade decreases. The difference in air pressure across the two sides of the blade creates both lift and drag. The force of the lift is stronger than the drag and this causes the rotor to spin. The rotor connects to the generator, either directly (if it's a direct drive turbine) or through a shaft and a series of gears (a gearbox) that speed up the rotation and allow for a physically smaller generator. This translation of aerodynamic force to rotation of a generator creates electricity.

Types of Wind Turbines

The majority of wind turbines fall into two basic types:

When wind turbines of any size are installed on the "customer" side of the electric meter, or are installed at or near the place where the energy they produce will be used, they're called "distributed wind.

Many turbines used in distributed applications are small wind turbines. Single small wind turbines-below 100 kilowatts-are typically used for residential, agricultural, and small commercial and industrial applications.

Small turbines can be used in hybrid energy systems with other distributed energy resources, such as microgrids powered by diesel generators, batteries, and photovoltaics.

These systems are called hybrid wind systems and are typically used in remote, off-grid locations( where a connection to the utility grid is not available) and are becoming more common in grid-connected applications for resiliency.

Learn more about distributed wind from the Distributed Wind Animation or read about what the Wind Energy Technologies Office is doing to support the deployment of distributed wind systems for homes, businesses, farms, and community wind projects.

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Wind is a form of solar energy caused by a combination of three concurrent events: The sun unevenly heating the atmosphere Irregularities of the earth's surface The rotation of the earth. Wind flow patterns and speeds vary greatly across the United States and are modified by bodies of water, vegetation, and differences in terrain.

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A article revolving around how NYC gets its water and the need for reservoirs and Aqueducts to supply NY, and the nation with ample, clean water.

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Watersheds, reservoirs and lakes

Before it goes anywhere, the city's drinking water starts out in three major watersheds -- the Delaware and Catskill systems west of the Hudson River and the Croton system just north of the city. In 2017, New York City got about 97 percent of its water from the Catskill/Delaware systems and about 3 percent from the Croton system, the DEP said.

The watersheds feed more than a dozen reservoirs and controlled lakes. The largest reservoir, the Pepacton, has a capacity of 140 billion gallons. The Ashokan in Ulster County, pictured, has a capacity of 123 billion gallons.

Officials take measurements throughout the reservoirs, looking at things like turbidity (water clarity) and contaminants, to select the highest quality water available at that moment to be released downstate.

A well protected water source

The water supply is so critical to the city that a dedicated police force with more than 200 members works 24 hours a day to prevent illegal dumping and other misuses of the waterways. During Hurricane Irene, the DEP Police were even called on to conduct water rescues.

Miles of aqueducts

Next, the water flows from the reservoirs and lakes through a system of aqueducts and tunnels. These include the 100-year-old Catskill Aqueduct, which extends 92 miles from the Ashokan Reservoir in the Catskill Mountains to the northern boundary of the city, and relies solely on gravity to carry the water. When it was completed in the early 1900s, the Catskill Aqueduct was considered by some as an engineering feat on the level of the Panama or Suez canals.

The 85-mile Delaware Aqueduct to its southwest is much newer, having been completed in the mid-1940s. The Delaware is so large that a two-man submarine has been used to inspect it for leaks. There are other aqueducts and tunnels, too. They all give the system a cascading effect, letting the water flow downstate.

Disinfecting the water

After traveling southeast through the Catskill and Delaware aqueducts, water arrives at the Kensico Reservoir about three miles north of White Plains in Westchester County. The reservoir is an important balancing reservoir for the daily demands of the city. Up until this point, the water has also been unfiltered and untreated. But now it gets treated with fluoride and disinfected at what is considered the world's largest ultraviolet treatment facility, as seen above. The UV treatment is especially useful for zapping Cryptosporidium and Giardia, which are not the names of punk bands but potentially harmful microorganisms.

A stop in Yonkers

The water makes another stop on its southerly voyage to the city: Hillview Reservoir in Yonkers. The DEP says the reservoir serves three critical functions. First, it balances daily demand (water consumption peaks twice during the day, in the morning and at night when people are home); second, water undergoes additional disinfection. And third, the reservoir serves to elevate the water so that when it does continue on, gravity propels it with enough force to flow into homes.

Into the city's tunnels and mains

From the aqueducts, water is distributed throughout the city via three tunnels -- No. 1 was put into service in 1917 and No. 2 has been in service since 1936. Tunnel No. 3, pictured, began serving the Bronx and upper Manhattan in 1998, and an extension into lower Manhattan was activated in 2013. Construction, which began in 1970 at a cost of about $5 billion, continues on the Brooklyn and Queens portions. Water then gets routed to distribution mains and then ...

Drink up

Finally, the water arrives in your home. If your building is less than six stories high, gravity does all the work. If not, then pumps in your building will help to move the water to the top floors. To maintain quality, testing is done at nearly 1,000 sampling stations around the city.

How good is the water that comes out of your faucet? Here's one way to look at it: The city is only one of five big municipalities that is allowed by the federal government to supply unfiltered water. If that's not enough, the DEP releases a yearly Water Quality Report offering information on the water supply. You can read the full 2017 report at nyc.gov/html/dep/pdf.

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Before it goes anywhere, the city's drinking water starts out in three major watersheds -- the Delaware and Catskill systems west of the Hudson River and the Croton system just north of the city. In 2017, New York City got about 97 percent of its water from the Catskill/Delaware systems and about 3 percent from the Croton system, the DEP said.

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A Pumped storage green energy facility that is located locally, a facility that I have visited and has inspired me with its beauty and tried and true processes. This article explains the processes and the common issues the plant has had.

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A in-depth explanation of Pumped Storage. A common processes that is exemplified at the local hydro-electric plant at the Blenheim-Gilboa Hydroelectric Power Station

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Hydroelectric Power: How it works, USGS Water-Science School

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Hydroelectric Power: How it works, the USGS Water-Science School

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A Wikipedia explanation of what hydro electric is, and some of the common processes and the correct terms for these processes.

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The Three Gorges Dam in Central China is the world's largest power-producing facility of any kind.

Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4,500 TWh in 2020, which is more than all other renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants. However, when constructed in lowland rainforest areas, where part of the forest is inundated, substantial amounts of greenhouse gases may be emitted.

Construction of a hydroelectric complex can have significant environmental impact, principally in loss of arable land and population displacement. They also disrupt the natural ecology of the river involved, affecting habitats and ecosystems, and siltation and erosion patterns. While dams can ameliorate the risks of flooding, dam failure can be catastrophic.

In 2021, global installed hydropower electrical capacity reached almost 1,400 GW, the highest among all renewable energy technologies. Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can be used in coastal regions.

China added 24 GW in 2022, accounting for nearly three-quarters of global hydropower capacity additions. Europe added 2 GW, the largest amount for the region since 1990. Meanwhile, globally, hydropower generation increased by 70 TWh (up 2%) in 2022 and remains the largest renewable energy source, surpassing all other technologies combined.

Museum Hydroelectric power plant "Under the Town" in Užice, Serbia, built in 1900.[10]

Hydropower has been used since ancient times to grind flour and perform other tasks. In the late 18th century hydraulic power provided the energy source needed for the start of the Industrial Revolution. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique, which described vertical- and horizontal-axis hydraulic machines, and in 1771 Richard Arkwright's combination of water power, the water frame, and continuous production played a significant part in the development of the factory system, with modern employment practices. In the 1840s the hydraulic power network was developed to generate and transmit hydro power to end users.

By the late 19th century, the electrical generator was developed and could now be coupled with hydraulics. The growing demand arising from the Industrial Revolution would drive development as well. In 1878, the world's first hydroelectric power scheme was developed at Cragside in Northumberland, England, by William Armstrong. It was used to power a single arc lamp in his art gallery. The old Schoelkopf Power Station No. 1, US, near Niagara Falls, began to produce electricity in 1881. The first Edison hydroelectric power station, the Vulcan Street Plant, began operating September 30, 1882, in Appleton, Wisconsin, with an output of about 12.5 kilowatts. By 1886 there were 45 hydroelectric power stations in the United States and Canada; and by 1889 there were 200 in the United States alone.

The Warwick Castle water-powered generator house, used for the generation of electricity for the castle from 1894 until 1940

At the beginning of the 20th century, many small hydroelectric power stations were being constructed by commercial companies in mountains near metropolitan areas. Grenoble, France held the International Exhibition of Hydropower and Tourism, with over one million visitors 1925. By 1920, when 40% of the power produced in the United States was hydroelectric, the Federal Power Act was enacted into law. The Act created the Federal Power Commission to regulate hydroelectric power stations on federal land and water. As the power stations became larger, their associated dams developed additional purposes, including flood control, irrigation and navigation. Federal funding became necessary for large-scale development, and federally owned corporations, such as the Tennessee Valley Authority (1933) and the Bonneville Power Administration (1937) were created. Additionally, the Bureau of Reclamation which had begun a series of western US irrigation projects in the early 20th century, was now constructing large hydroelectric projects such as the 1928 Hoover Dam. The United States Army Corps of Engineers was also involved in hydroelectric development, completing the Bonneville Dam in 1937 and being recognized by the Flood Control Act of 1936 as the premier federal flood control agency.

Hydroelectric power stations continued to become larger throughout the 20th century. Hydropower was referred to as "white coal". Hoover Dam's initial 1,345 MW power station was the world's largest hydroelectric power station in 1936; it was eclipsed by the 6,809 MW Grand Coulee Dam in 1942. The Itaipu Dam opened in 1984 in South America as the largest, producing 14 GW, but was surpassed in 2008 by the Three Gorges Dam in China at 22.5 GW. Hydroelectricity would eventually supply some countries, including Norway, Democratic Republic of the Congo, Paraguay and Brazil, with over 85% of their electricity.

Future potential

In 2021 the International Energy Agency (IEA) said that more efforts are needed to help limit climate change. Some countries have highly developed their hydropower potential and have very little room for growth: Switzerland produces 88% of its potential and Mexico 80%. In 2022, the IEA released a main-case forecast of 141 GW generated by hydropower over 2022-2027, which is slightly lower than deployment achieved from 2017-2022. Because environmental permitting and construction times are long, they estimate hydropower potential will remain limited, with only an additional 40 GW deemed possible in the accelerated case.

Modernization of existing infrastructure

In 2021 the IEA said that major modernisation refurbishments are required.

Generating methods

Conventional (dams)

Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. The power extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head. A large pipe (the " penstock") delivers water from the reservoir to the turbine.

Pumped-storage

This method produces electricity to supply high peak demands by moving water between reservoirs at different elevations. At times of low electrical demand, the excess generation capacity is used to pump water into the higher reservoir, thus providing demand side response. When the demand becomes greater, water is released back into the lower reservoir through a turbine. In 2021 pumped-storage schemes provided almost 85% of the world's 190 GW of grid energy storage and improve the daily capacity factor of the generation system. Pumped storage is not an energy source, and appears as a negative number in listings.

Run-of-the-river

Run-of-the-river hydroelectric stations are those with small or no reservoir capacity, so that only the water coming from upstream is available for generation at that moment, and any oversupply must pass unused. A constant supply of water from a lake or existing reservoir upstream is a significant advantage in choosing sites for run-of-the-river.

A tidal power station makes use of the daily rise and fall of ocean water due to tides; such sources are highly predictable, and if conditions permit construction of reservoirs, can also be dispatchable to generate power during high demand periods. Less common types of hydro schemes use water's kinetic energy or undammed sources such as undershot water wheels. Tidal power is viable in a relatively small number of locations around the world.

Sizes, types and capacities of hydroelectric facilities

The classification of hydropower plants starts with two top-level categories:

small hydropower plants (SHP) and

large hydropower plants (LHP).

The classification of a plant as an SHP or LHP is primarily based on its nameplate capacity, the threshold varies by the country, but in any case a plant with the capacity of 50 MW or more is considered an LHP. As an example, for China, SHP power is below 25 MW, for India - below 15 MW, most of Europe - below 10 MW.

The SHP and LHP categories are further subdivided into many subcategories that are not mutually exclusive. For example, a low-head hydro power plant with hydrostatic head of few meters to few tens of meters can be classified either as an SHP or an LHP. The other distinction between SHP and LHP is the degree of the water flow regulation: a typical SHP primarily uses the natural water discharge with very little regulation in comparison to an LHP. Therefore, the term SHP is frequently used as a synonym for the run-of-the-river power plant.

Large facilities

The largest power producers in the world are hydroelectric power stations, with some hydroelectric facilities capable of generating more than double the installed capacities of the current largest nuclear power stations.

Although no official definition exists for the capacity range of large hydroelectric power stations, facilities from over a few hundred megawatts are generally considered large hydroelectric facilities.

Currently, only seven facilities over () are in operation worldwide, see table below.

Small hydro is hydroelectric power on a scale serving a small community or industrial plant. The definition of a small hydro project varies but a generating capacity of up to 10 megawatts (MW) is generally accepted as the upper limit. This may be stretched to 25 MW and 30 MW in Canada and the United States.

A micro-hydro facility in Vietnam

Pico hydroelectricity in Mondulkiri, Cambodia

Small hydro stations may be connected to conventional electrical distribution networks as a source of low-cost renewable energy. Alternatively, small hydro projects may be built in isolated areas that would be uneconomic to serve from a grid, or in areas where there is no national electrical distribution network. Since small hydro projects usually have minimal reservoirs and civil construction work, they are seen as having a relatively low environmental impact compared to large hydro. This decreased environmental impact depends strongly on the balance between stream flow and power production.[citation needed ]

Micro hydro means hydroelectric power installations that typically produce up to of power. These installations can provide power to an isolated home or small community, or are sometimes connected to electric power networks. There are many of these installations around the world, particularly in developing nations as they can provide an economical source of energy without purchase of fuel. Micro hydro systems complement photovoltaic solar energy systems because in many areas water flow, and thus available hydro power, is highest in the winter when solar energy is at a minimum.

Pico hydro is hydroelectric power generation of under . It is useful in small, remote communities that require only a small amount of electricity. For example, the 1.1 kW Intermediate Technology Development Group Pico Hydro Project in Kenya supplies 57 homes with very small electric loads (e.g., a couple of lights and a phone charger, or a small TV/radio). Even smaller turbines of 200-300 W may power a few homes in a developing country with a drop of only 1 m (3 ft). A Pico-hydro setup is typically run-of-the-river, meaning that dams are not used, but rather pipes divert some of the flow, drop this down a gradient, and through the turbine before returning it to the stream.

Underground

An underground power station is generally used at large facilities and makes use of a large natural height difference between two waterways, such as a waterfall or mountain lake. A tunnel is constructed to take water from the high reservoir to the generating hall built in a cavern near the lowest point of the water tunnel and a horizontal tailrace taking water away to the lower outlet waterway.

Measurement of the tailrace and forebay rates at the Limestone Generating Station in Manitoba, Canada.

Calculating available power

A simple formula for approximating electric power production at a hydroelectric station is:

where

Efficiency is often higher (that is, closer to 1) with larger and more modern turbines. Annual electric energy production depends on the available water supply. In some installations, the water flow rate can vary by a factor of 10:1 over the course of a year.[citation needed ]

Properties

Advantages

The 360 Ffestiniog Power Station can generate MW of electricity within 60 seconds of the demand arising.

Flexibility

Hydropower is a flexible source of electricity since stations can be ramped up and down very quickly to adapt to changing energy demands. Hydro turbines have a start-up time of the order of a few minutes. Although battery power is quicker its capacity is tiny compared to hydro. It takes less than 10 minutes to bring most hydro units from cold start-up to full load; this is quicker than nuclear and almost all fossil fuel power. Power generation can also be decreased quickly when there is a surplus power generation. Hence the limited capacity of hydropower units is not generally used to produce base power except for vacating the flood pool or meeting downstream needs. Instead, it can serve as backup for non-hydro generators.

High value power

The major advantage of conventional hydroelectric dams with reservoirs is their ability to store water at low cost for dispatch later as high value clean electricity. In 2021, the IEA estimated that the "reservoirs of all existing conventional hydropower plants combined can store a total of 1,500 terawatt-hours (TWh) of electrical energy in one full cycle" which was "about 170 times more energy than the global fleet of pumped storage hydropower plants". Battery storage capacity is not expected to overtake pumped storage during the 2020s. When used as peak power to meet demand, hydroelectricity has a higher value than baseload power and a much higher value compared to intermittent energy sources such as wind and solar.

Hydroelectric stations have long economic lives, with some plants still in service after 50-100 years. Operating labor cost is also usually low, as plants are automated and have few personnel on site during normal operation.

Where a dam serves multiple purposes, a hydroelectric station may be added with relatively low construction cost, providing a useful revenue stream to offset the costs of dam operation. It has been calculated that the sale of electricity from the Three Gorges Dam will cover the construction costs after 5 to 8 years of full generation. However, some data shows that in most countries large hydropower dams will be too costly and take too long to build to deliver a positive risk adjusted return, unless appropriate risk management measures are put in place.

Suitability for industrial applications

While many hydroelectric projects supply public electricity networks, some are created to serve specific industrial enterprises. Dedicated hydroelectric projects are often built to provide the substantial amounts of electricity needed for aluminium electrolytic plants, for example. The Grand Coulee Dam switched to support Alcoa aluminium in Bellingham, Washington, United States for American World War II airplanes before it was allowed to provide irrigation and power to citizens (in addition to aluminium power) after the war. In Suriname, the Brokopondo Reservoir was constructed to provide electricity for the Alcoa aluminium industry. New Zealand's Manapouri Power Station was constructed to supply electricity to the aluminium smelter at Tiwai Point.

Since hydroelectric dams do not use fuel, power generation does not produce carbon dioxide. While carbon dioxide is initially produced during construction of the project, and some methane is given off annually by reservoirs, hydro has one of the lowest lifecycle greenhouse gas emissions for electricity generation. The low greenhouse gas impact of hydroelectricity is found especially in temperate climates. Greater greenhouse gas emission impacts are found in the tropical regions because the reservoirs of power stations in tropical regions produce a larger amount of methane than those in temperate areas.

Like other non-fossil fuel sources, hydropower also has no emissions of sulfur dioxide, nitrogen oxides, or other particulates.

Other uses of the reservoir

Reservoirs created by hydroelectric schemes often provide facilities for water sports, and become tourist attractions themselves. In some countries, aquaculture in reservoirs is common. Multi-use dams installed for irrigation support agriculture with a relatively constant water supply. Large hydro dams can control floods, which would otherwise affect people living downstream of the project. Managing dams which are also used for other purposes, such as irrigation, is complicated.

Disadvantages

In 2021 the IEA called for "robust sustainability standards for all hydropower development with streamlined rules and regulations".

Ecosystem damage and loss of land

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.

Large reservoirs associated with traditional hydroelectric power stations result in submersion of extensive areas upstream of the dams, sometimes destroying biologically rich and productive lowland and riverine valley forests, marshland and grasslands. Damming interrupts the flow of rivers and can harm local ecosystems, and building large dams and reservoirs often involves displacing people and wildlife. The loss of land is often exacerbated by habitat fragmentation of surrounding areas caused by the reservoir.

Hydroelectric projects can be disruptive to surrounding aquatic ecosystems both upstream and downstream of the plant site. Generation of hydroelectric power changes the downstream river environment. Water exiting a turbine usually contains very little suspended sediment, which can lead to scouring of river beds and loss of riverbanks. The turbines also will kill large portions of the fauna passing through, for instance 70% of the eel passing a turbine will perish immediately. Since turbine gates are often opened intermittently, rapid or even daily fluctuations in river flow are observed.

Drought and water loss by evaporation

Drought and seasonal changes in rainfall can severely limit hydropower. Water may also be lost by evaporation.

Siltation and flow shortage

When water flows it has the ability to transport particles heavier than itself downstream. This has a negative effect on dams and subsequently their power stations, particularly those on rivers or within catchment areas with high siltation. Siltation can fill a reservoir and reduce its capacity to control floods along with causing additional horizontal pressure on the upstream portion of the dam. Eventually, some reservoirs can become full of sediment and useless or over-top during a flood and fail.

Changes in the amount of river flow will correlate with the amount of energy produced by a dam. Lower river flows will reduce the amount of live storage in a reservoir therefore reducing the amount of water that can be used for hydroelectricity. The result of diminished river flow can be power shortages in areas that depend heavily on hydroelectric power. The risk of flow shortage may increase as a result of climate change. One study from the Colorado River in the United States suggest that modest climate changes, such as an increase in temperature in 2 degree Celsius resulting in a 10% decline in precipitation, might reduce river run-off by up to 40%. Brazil in particular is vulnerable due to its heavy reliance on hydroelectricity, as increasing temperatures, lower water flow and alterations in the rainfall regime, could reduce total energy production by 7% annually by the end of the century.

Methane emissions (from reservoirs)

The 2,080 Hoover Dam in the United States is a large conventional dammed-hydro facility, with an installed capacity of MW.

Lower positive impacts are found in the tropical regions. In lowland rainforest areas, where inundation of a part of the forest is necessary, it has been noted that the reservoirs of power plants produce substantial amounts of methane. This is due to plant material in flooded areas decaying in an anaerobic environment and forming methane, a greenhouse gas. According to the World Commission on Dams report, where the reservoir is large compared to the generating capacity (less than 100 watts per square metre of surface area) and no clearing of the forests in the area was undertaken prior to impoundment of the reservoir, greenhouse gas emissions from the reservoir may be higher than those of a conventional oil-fired thermal generation plant.

In boreal reservoirs of Canada and Northern Europe, however, greenhouse gas emissions are typically only 2% to 8% of any kind of conventional fossil-fuel thermal generation. A new class of underwater logging operation that targets drowned forests can mitigate the effect of forest decay.

Relocation

Another disadvantage of hydroelectric dams is the need to relocate the people living where the reservoirs are planned. In 2000, the World Commission on Dams estimated that dams had physically displaced 40-80 million people worldwide.

Failure risks

Because large conventional dammed-hydro facilities hold back large volumes of water, a failure due to poor construction, natural disasters or sabotage can be catastrophic to downriver settlements and infrastructure.

During Typhoon Nina in 1975 Banqiao Dam in Southern China failed when more than a year's worth of rain fell within 24 hours (see 1975 Banqiao Dam failure). The resulting flood resulted in the deaths of 26,000 people, and another 145,000 from epidemics. Millions were left homeless.

The creation of a dam in a geologically inappropriate location may cause disasters such as 1963 disaster at Vajont Dam in Italy, where almost 2,000 people died.

The Malpasset Dam failure in Fréjus on the French Riviera (Côte d'Azur), southern France, collapsed on December 2, 1959, killing 423 people in the resulting flood.

Smaller dams and micro hydro facilities create less risk, but can form continuing hazards even after being decommissioned. For example, the small earthen embankment Kelly Barnes Dam failed in 1977, twenty years after its power station was decommissioned, causing 39 deaths.

Comparison and interactions with other methods of power generation

Hydroelectricity eliminates the flue gas emissions from fossil fuel combustion, including pollutants such as sulfur dioxide, nitric oxide, carbon monoxide, dust, and mercury in the coal. Hydroelectricity also avoids the hazards of coal mining and the indirect health effects of coal emissions. In 2021 the IEA said that government energy policy should "price in the value of the multiple public benefits provided by hydropower plants".

Nuclear power

Nuclear power is relatively inflexible; although it can reduce its output reasonably quickly. Since the cost of nuclear power is dominated by its high infrastructure costs, the cost per unit energy goes up significantly with low production. Because of this, nuclear power is mostly used for baseload. By way of contrast, hydroelectricity can supply peak power at much lower cost. Hydroelectricity is thus often used to complement nuclear or other sources for load following. Country examples where they are paired in a close to 50/50 share include the electric grid in Switzerland, the Electricity sector in Sweden and to a lesser extent, Ukraine and the Electricity sector in Finland.

Wind power goes through predictable variation by season, but is intermittent on a daily basis. Maximum wind generation has little relationship to peak daily electricity consumption, the wind may peak at night when power is not needed or be still during the day when electrical demand is highest. Occasionally weather patterns can result in low wind for days or weeks at a time, a hydroelectric reservoir capable of storing weeks of output is useful to balance generation on the grid. Peak wind power can be offset by minimum hydropower and minimum wind can be offset with maximum hydropower. In this way the easily regulated character of hydroelectricity is used to compensate for the intermittent nature of wind power. Conversely, in some cases wind power can be used to spare water for later use in dry seasons.

An example of this is Norway's trading with Sweden, Denmark, the Netherlands, Germany and the UK. Norway is 98% hydropower, while its flatland neighbors have wind power. In areas that do not have hydropower, pumped storage serves a similar role, but at a much higher cost and 20% lower efficiency.[citation needed ]

Hydro power by country

Share of electricity production from hydropower, 2022[66]

Yearly hydro generation by continent[67]

Hydro generation by country, 2021[67]

In 2022 hydro generated 4,289 TWh, 15% of total electricity and half of renewables. Of the world total, China (30%) produced the most, followed by Brazil (10%), Canada (9.2%), the United States (5.8%) and Russia (4.6%).

Paraguay produces nearly all of its electricity from hydro and exports far more than it uses. Large plants tend to be built by governments, so most capacity (70%) is publicly owned, even though most plants (nearly 70%) are owned and operated by the private sector, as of 2021.

The following table lists these data for each country:

Data are sourced from Ember and refer to the year 2022 unless otherwise specified. Only includes countries with more than 1 TWh of generation. Links for each location go to the relevant hydro power page, when available.

This section needs expansion. You can help by adding to it.

The weighted average cost of capital is a major factor.

References

External links

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Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4,500 TWh in 2020, which is more than all other renewable sources combined and also more than nuclear power.

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Articles on why green energy is a responsible choice as well as some key images to explain common processes.

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Hydroelectric Power Diagram Hydroelectric Power Graph Hydroelectric Power Plant Hoover Dam Hydroelectric Power Hydroelectric Power Turbine Hydroelectric Power Station Hydroelectric Power Pros and Cons Hydroelectric Power Cartoon Wind Power Solar Power Geothermal Energy Biofuel Biomass Hydropower Fossil Fuels Geothermal Dam Hoover Dam Hydroelectric Energy Hydroelectric Dam Hydroelectric Plant Solar Energy

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Turbine that would likely be place inside of a hydro-Electric plant. Very complex and efficient.

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Family heritage is on large equipment, in particular, large Bull-Dozers like the one in the image.

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Beautiful scenery and space aged forums interest me, learning how to build a structure to look as though it belongs in the near by area is a significant goal to my design procedures.

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Heavy equipment enthuses me to peruse this field.

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Bridges and other large/complex projects are the foundation this nation was founded on.

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Barges, Cranes, and other large forums that help create significant structures and there pathways to creating those structures is always a heavy observed interest of mine.

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Beautiful forums in nature, as well as working in nature inspires me to peruse Heavy civil.

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Snyder family owned Falls, Located in Delhi NY.
Inspiration to some day create hydro electric plant on falls

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The process of creating power, based of a raw resource is the process of the future.

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Large damns and other Hydro-powered structures, as well as green electric is the process of the future.