How does dams generate electricity

Also controls the flow of water. The reservoir that is formed is, in effect, stored energy. The force of falling water pushing against the turbine's blades causes the turbine to spin. A water turbine is much like a windmill, except the energy is provided by falling water instead of wind. The turbine converts the kinetic energy of falling water into mechanical energy.

Connected to the turbine by shafts and possibly gears so when the turbine spins it causes the generator to spin also. Converts the mechanical energy from the turbine into electric energy.

Generators in hydropower plants work just like the generators in other types of power plants. Transmission lines. Conduct electricity from the hydropower plant to homes and business. The amount of electricity a hydropower plant produces depends on two factors: How Far the Water Falls.

The farther the water falls, the more power it has. Generally, the distance that the water falls depends on the size of the dam. The higher the dam, the farther the water falls and the more power it has. Scientists would say that the power of falling water is "directly proportional" to the distance it falls.

Large scale hydroelectricity projects typically involve dams. Run-of-river and tidal projects also harness the power of moving water to generate renewable electricity. A hydroelectric dam converts the potential energy stored in a water reservoir behind a dam to mechanical energy—mechanical energy is also known as kinetic energy. As the water flows down through the dam its kinetic energy is used to turn a turbine.

Check out this video from the United States Department of Energy for more information on how hydroelectricity is generated:. Curious about the energy terminology used in this piece? The U. A hydroelectric generator converts this mechanical energy into electricity. The operation of a generator is based on the principles discovered by Faraday.

He found that when a magnet is moved past a conductor, it causes electricity to flow. In a large generator, electromagnets are made by circulating direct current through loops of wire wound around stacks of magnetic steel laminations. These are called field poles, and are mounted on the perimeter of the rotor. The rotor is attached to the turbine shaft, and rotates at a fixed speed.

When the rotor turns, it causes the field poles the electromagnets to move past the conductors mounted in the stator. This, in turn, causes electricity to flow and a voltage to develop at the generator output terminals. Demand for electricity is not "flat" and constant. Demand goes up and down during the day, and overnight there is less need for electricity in homes, businesses, and other facilities.

For example, here in Atlanta, Georgia at PM on a hot August weekend day, you can bet there is a huge demand for electricity to run millions of air conditioners! But, 12 hours later at AM Hydroelectric plants are more efficient at providing for peak power demands during short periods than are fossil-fuel and nuclear power plants, and one way of doing that is by using "pumped storage", which reuses the same water more than once.

Pumped storage is a method of keeping water in reserve for peak period power demands by pumping water that has already flowed through the turbines back up a storage pool above the power plant at a time when customer demand for energy is low, such as during the middle of the night.

The water is then allowed to flow back through the turbine-generators at times when demand is high and a heavy load is placed on the system. The reservoir acts much like a battery, storing power in the form of water when demands are low and producing maximum power during daily and seasonal peak periods. An advantage of pumped storage is that hydroelectric generating units are able to start up quickly and make rapid adjustments in output. They operate efficiently when used for one hour or several hours.

Because pumped storage reservoirs are relatively small, construction costs are generally low compared with conventional hydropower facilities. Water is everywhere, which is fortunate for all of humanity, as water is essential for life. Even though water is not always available in the needed quantity and quality for all people everywhere, people have learned to get and use water for all of their water needs, from drinking, cleaning, irrigating crops, producing electricity, and for just having fun.

Nothing is perfect on Earth, and that includes the production of electricity using flowing water. Hydroelectric-production facilities are indeed not perfect a dam costs a lot to build and also can have negative effects on the environment and local ecology , but there are a number of advantages of hydroelectric-power production as opposed to fossil-fuel power production. Gravity causes it to fall through the penstock. The Three Gorges Dam is the world's largest power. Tephra-laden water filtering through the turbines has necessitated the replacement of four turbines in 21 years.

The Agoyan Dam and its orange floodgates are designed to let highly turbid water bypass the turbines so as to avoid accelerated wear of generation components.