How Is A Dam Used To Make Electricity?

  • HOME OF THE WATER SCIENCE SCHOOL Topics Concerning Water Use So, how do we harness the power of water to generate electricity? Hydroelectric and coal-fired power stations both generate electricity in the same way. In both cases, a power source is used to turn a turbine, a propeller-like component that subsequently rotates a metal shaft in an electric generator, which is the motor that generates energy. The turbine blades of a coal-fired power plant are turned by steam, whereas the turbine blades in a hydroelectric facility are turned by falling water. The outcome is the same.

Take a look at this diagram of a hydroelectric power plant (courtesy of the Tennessee Valley Authority) for more information:

The idea is to construct a dam on a major river with a significant drop in elevation (there are not many hydroelectric plants in Kansas or Florida). The reservoir behind the dam holds a lot of water. The water intake is located towards the bottom of the dam wall. It falls through the penstock inside the dam because to gravity. A turbine propellor is located at the end of the penstock and is spun by the running water. The turbine’s shaft is fed into the generator, which generates electricity. The generator is connected to power wires that supply electricity to your and my homes. The water flows past the propeller and into the river past the dam via the tailrace. By the way, playing in the water directly below a dam while the water is released is not a smart idea!

A turbine and generator produce the electricity

The Corps of Engineers explains how this generator operates as follows:

“The energy of flowing water is converted into mechanical energy by a hydraulic turbine. This mechanical energy is converted into electricity by a hydropower generator. The principles discovered by Faraday are used to operate generators. He discovered that moving a magnet past a conductor causes electricity to flow. Electromagnets are made in huge generators by passing direct current through loops of wire wound around stacks of magnetic steel laminations. These are known as field poles, and they are positioned around the rotor’s perimeter. The turbine shaft is connected to the rotor, which rotates at a constant speed. The field poles (the electromagnets) pass past the conductors positioned in the stator as the rotor rotates. This results in the flow of electricity and the development of a voltage at the generator output terminals.”

Pumped storage: Reusing water for peak electricity demand

Electricity demand is not “flat” or steady. During the day, demand fluctuates, and there is less need for electricity in homes, companies, and other facilities at night. For example, at 5:00 p.m. on a hot August weekend day in Atlanta, Georgia, you can bet there is a high demand for electricity to power millions of air conditioners! However, at 5:00 a.m., 12 hours later…. Not at all. Hydroelectric facilities are more efficient than fossil-fuel and nuclear power plants at meeting peak power demands during short periods, and one way to accomplish so is to use “pumped storage,” which reuses the same water multiple times.

Pumped storage is a way of storing water for peak period power demands by pumping water that has already gone through the turbines back up a storage pool above the power plant at a time when customer demand for energy is low, such as at night. When demand is strong and the system is under a significant load, the water is permitted to flow back through the turbine-generators.

When demand is low, the reservoir operates like a battery, storing energy in the form of water and producing maximum power during daily and seasonal peak periods. Pumped storage has the advantage of allowing hydroelectric producing units to start up rapidly and alter output quickly. When used for one hour or several hours, they perform well. Construction expenses for pumped storage reservoirs are often lower than for traditional hydropower projects due to their compact size.

How do dams generate electricity?

Impoundment, diversion, and pumped storage are the three types of hydroelectric facilities. Dams are used in some hydroelectric facilities, although they are not used in others.

Despite the fact that not all dams were built for hydropower, they have shown to be effective in delivering large amounts of renewable energy to the grid. There are more than 90,000 dams in the United States, but only about 2,300 produce electricity as of 2020. The dams used for recreation, stock/farm ponds, flood control, water supply, and irrigation are among the others.

Hydropower plants come in a variety of sizes, from tiny systems for a single home or community to massive projects that provide electricity for utilities. Find out more about hydropower plant sizes.


An impoundment facility is the most prevalent type of hydroelectric power plant. A dam is used to store river water in a reservoir at an impoundment plant, which is usually a big hydroelectric system. Water released from the reservoir spins a turbine, which then activates a generator, which generates power. The water might be released to satisfy fluctuating electrical needs, as well as other purposes including flood control, recreation, fish passage, and other environmental and water quality concerns.

What is the definition of a hydroelectric dam?

One of the most important components of a hydroelectric facility is a hydroelectric dam. A dam is a massive man-made structure designed to keep a body of water contained. Dams are built for a variety of reasons, including the generation of hydroelectric power and the control of river flow and flooding.

What are the two methods for producing electricity?

The United States generates electricity using a variety of energy sources and technologies. Over time, the sources and technologies have evolved, and some are now used more frequently than others.

Fossil fuels (coal, natural gas, and petroleum), nuclear energy, and renewable energy sources are the three major forms of energy for electricity generation. Steam turbines use fossil fuels, nuclear, biomass, geothermal, and solar thermal energy to create the majority of power. Gas turbines, hydro turbines, wind turbines, and solar photovoltaics are some of the other important electricity producing systems.

What are the six different ways to generate electricity?

You’ll go over the six different ways electricity is created in this activity: chemical, friction, heat, light, magnetism, and pressure.

Electricity is generated in power plants in a variety of ways.

The process of creating electricity from primary energy sources is known as electricity generation. It is the stage prior to delivery (transmission, distribution, etc.) to end customers or storage for utilities in the electric power business (using, for example, the pumped-storage method).

Because electricity is not found naturally, it must be “made” (that is, transforming other forms of energy to electricity). Production takes place at power plants (also called “power plants”). Electromechanical generators, primarily driven by heat engines fueled by combustion or nuclear fission, but also by other means such as the kinetic energy of flowing water and wind, are used to create electricity at power plants. Solar photovoltaics and geothermal power are two alternative energy sources.

The phase-out of coal-fired power plants and, eventually, gas-fired power plants, as well as the capture of their greenhouse gas emissions, are critical components of the energy revolution required to prevent climate change. With the electrification of transportation, residences, and industry, much more solar and wind power is expected to be required.

How is electricity designed for children?

  • Huge generators produce electricity in a generating plant. Wind, coal, natural gas, or water can all be used in power plants.
  • The current is routed through transformers, which boost the voltage and allow the electricity to travel vast distances.
  • The electrical charge travels across the country via high-voltage transmission cables.
  • It arrives to a substation, where the voltage is reduced so that it can be transmitted via shorter power lines.
  • It makes its way to your community via distribution lines. Smaller transformers lower the voltage so that it is safe to use in our homes. These smaller transformers can be fixed on poles or sit on the ground (they’re the enormous green boxes that are known as pad mount transformers).
  • It connects to your home and runs through a meter that tracks how much energy your household consumes.
  • Breakers or fuses safeguard the cables inside your house from being overloaded at the service panel, which is located in your basement or garage.

In a hydroelectric power plant, what method is used to generate electricity?

In a hydroelectric power plant, the kinetic energy of water is employed to generate electricity via a running dynamo.