A turbine converts the kinetic energy of falling water into mechanical energy. Then a generator converts the mechanical energy from the turbine into electrical energy. Hydroplants range in size from "micro-hydros" that power only a few homes to giant dams like Hoover Dam that provide electricity for millions of people.
The photo on the right shows the Alexander Hydroelectric Plant on the Wisconsin River, a medium-sized plant that produces enough electricity to serve about 8, people. Let's say that there is a small dam in your area that is not used to produce electricity. Maybe the dam is used to provide water to irrigate farmlands or maybe it was built to make a lake for recreation.
As we explained above, you need to know two things:. Now all we need to do is a little mathematics. Engineers have found that we can calculate the power of a dam using the following formula:.
To get an idea what kilowatts means, let's see how much electric energy we can make in a year. Since electric energy is normally measured in kilowatt-hours, we multiply the power from our dam by the number of hours in a year. The average annual residential energy use in the U. So we can figure out how many people our dam could serve by dividing the annual energy production by 3, So our local irrigation or recreation dam could provide enough renewable energy to meet the residential needs of people if we added a turbine and generator.
Note: Before you decide to add hydropower to a dam, have a hydropower engineer review your calculations and consult with the local resource agencies to be sure you can obtain any permits that are required. Each TeachEngineering lesson or activity is correlated to one or more K science, technology, engineering or math STEM educational standards.
In the ASN, standards are hierarchically structured: first by source; e. Use evidence to construct an explanation relating the speed of an object to the energy of that object. Grade 4. Do you agree with this alignment? Thanks for your feedback! Alignment agreement: Thanks for your feedback!
Develop a model to describe that when the arrangement of objects interacting at a distance changes, different amounts of potential energy are stored in the system. Grades 6 - 8. View aligned curriculum. Students learn how water is used to generate electricity. They investigate water's potential-to-kinetic energy transformation in hands-on activities about falling water and waterwheels. During the activities, they take measurements, calculate averages and graph results.
Hydropower generation is introduced to students as a common purpose and benefit of constructing dams. Through an introduction to kinetic and potential energy, students come to understand how a dam creates electricity. Students learn and discuss the advantages and disadvantages of renewable and non-renewable energy sources.
They also learn about our nation's electric power grid and what it means for a residential home to be "off the grid. This lesson provides students with an overview of the electric power industry in the United States. Students also become familiar with the environmental impacts associated with a variety of energy sources.
What is energy? Answer: Something that can do work. Have you ever heard of potential or kinetic energy? Well, potential energy is simply the "stored" energy of an object. An object's potential energy depends partly on its height and gravity. Kinetic energy is the energy of the object in motion. As an object falls, or moves down an incline, its potential energy is converted into kinetic energy.
So, a falling object or one rolling or sliding down a hill loses its potential energy as it increases its kinetic energy. Installation of huge water turbines at Ft. Loudoun Dam, TN.
The new technology of free-flow hydro works a lot like a wind farm, except with underwater turbines. Used with permission. When we think of water, potential energy is the energy of the water as it sits calmly in a reservoir or lake.
The kinetic energy of water is when it is rushing through a river, down a waterfall or through a hydroelectric power plant.
The force of the kinetic energy is dependent on the height and mass of the falling water. Hydroelectric is when water is used to produce electricity.
Civil engineers design and build dams and hydroelectric power plants that use the energy of falling water to turn the blades of turbines to generate electricity that we can use in our homes. So, it is actually the kinetic energy of water moving through a power plant that can produce electricity. In this activity, we are going to drop water from different heights to demonstrate how the kinetic energy of water changes when it hits the floor.
Engineers must understand how height affects the amount of kinetic energy so they create a reservoir that holds the correct amount of water and design a hydroelectric power plant that produces the necessary amount of electricity. Since water falls too fast for us to measure the velocity or kinetic energy of the water directly, we will measure the size of the splash produced to show us how much kinetic energy exists.
Figure 1. How to use a straw like a water dropper. For example, a spinning top, a falling object and a rolling ball all have kinetic energy. The motion, if resisted by a force, does work.
Who is Who Environment. Web Search Environment. Hydroelectric Energy is the energy derived from the power of water. When water moves as in flowing river or falls through height as in water falls or fall after crossing a dam it generates some forms of useful energy.
Energy due to motion is Kinetic Energy while energy due to fall is Potential Energy. These energy sources are made use of in hydroelectric power plants to generate electricity for home and industry uses.
An hydroelectric power station may use a natural water drops such as water falls as in Niagra fall - the picture above or rapids. The water falling through the fall or the dam is channelled through the plant intake into a pipe penstock.
The construction of the penstock at most stations allows the water to go through a further fall before reaching the plant. This additional fall increases the water flow and pressure thus producing a greater driving force required to run the power plant. This spinning turns the ROTOR electromagnetic device which is attached to the other end of the turbines shaft.
The electricity generated is conducted through the STATOR to a transformer which steps up the voltage and allow it to be transmitted to homes and industries for use.
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