Hydropower
Water can be a powerful force in nature. Its power can be seen in floods that uproot trees or heard in the roar of a waterfall. That power, called waterpower or hydropower, can be used as an alternative energy source. Unlike fossil fuels, it cannot be used up. When waterpower is harnessed, it can be used to create electricity, or hydroelectricity. Hydropower is power that is generated from moving water such as rivers. People have been using the power of moving water in streams and rivers for a long time to make machines work. Hydropower was one of the first ways we made electricity, and it's still a big source of renewable energy in the U.S. Fast Facts!
|
Renewable Energy
Hydropower is a renewable energy source. This means that using a dam or a river to generate electricity doesn't use up any limited resources like coal or gasoline.
Hydropower is a renewable energy source. This means that using a dam or a river to generate electricity doesn't use up any limited resources like coal or gasoline.
Hydropower relies on the Water Cycle
Understanding the water cycle is important to understanding hydropower. The water cycle has three steps:
Understanding the water cycle is important to understanding hydropower. The water cycle has three steps:
- Solar energy heats water on the surface of rivers, lakes, and oceans, which causes the water to evaporate.
- Water vapor condenses into clouds and falls as precipitation—rain and snow.
- Precipitation collects in streams and rivers, which empty into oceans and lakes, where it evaporates and begins the cycle again.
How do we get Power from Water?
Falling or flowing water from a big river has a lot of energy. We can harness this by forcing the water through a pipe called a penstock. As the water flows through the pipe it turns the blades of a turbine which spins an electric generator. As long as the water is flowing, the generator will be able to provide electricity.
Hydroelectric power plants are usually located in dams that are built across rivers. In a dam water is collected at a higher elevation and is then led downward through large pipes to a lower elevation. The falling water causes wheels called water turbines to rotate. The rotating turbines run machines called generators, which produce electricity.
Oceans can also be used to create hydroelectricity. Those waterpower sources are known as tidal power and wave power. Tidal power is created during the tide, when the water level along the oceanic coast changes. Wave power is harnessed by the up-and-down motion of waves.
Falling or flowing water from a big river has a lot of energy. We can harness this by forcing the water through a pipe called a penstock. As the water flows through the pipe it turns the blades of a turbine which spins an electric generator. As long as the water is flowing, the generator will be able to provide electricity.
Hydroelectric power plants are usually located in dams that are built across rivers. In a dam water is collected at a higher elevation and is then led downward through large pipes to a lower elevation. The falling water causes wheels called water turbines to rotate. The rotating turbines run machines called generators, which produce electricity.
Oceans can also be used to create hydroelectricity. Those waterpower sources are known as tidal power and wave power. Tidal power is created during the tide, when the water level along the oceanic coast changes. Wave power is harnessed by the up-and-down motion of waves.
Hydroelectric Power Plants
Because the source of hydroelectric power is water, hydroelectric power plants are usually located on or near a water source. The volume of the water flow and the change in elevation (or fall) from one point to another determine the amount of available energy in moving water. In general, the greater the water flow and the higher the fall, the more electricity a hydropower plant can produce. A big river, such as the Columbia River that forms the border between Oregon and Washington, carries a great deal of energy in its flow. Water descending rapidly from a high point, such as Niagara Falls in New York, also has substantial energy in its flow.
At hydropower plants, water flows through a pipe, or penstock, then pushes against and turns blades in a turbine to spin a generator to produce electricity.
There are three main ways that engineers design hydroelectric power plants:
Because the source of hydroelectric power is water, hydroelectric power plants are usually located on or near a water source. The volume of the water flow and the change in elevation (or fall) from one point to another determine the amount of available energy in moving water. In general, the greater the water flow and the higher the fall, the more electricity a hydropower plant can produce. A big river, such as the Columbia River that forms the border between Oregon and Washington, carries a great deal of energy in its flow. Water descending rapidly from a high point, such as Niagara Falls in New York, also has substantial energy in its flow.
At hydropower plants, water flows through a pipe, or penstock, then pushes against and turns blades in a turbine to spin a generator to produce electricity.
There are three main ways that engineers design hydroelectric power plants:
- Storage System - The storage system uses a dam. The dam slows the flow of a river and stores up water in a lake. A portion of the water is released into the river at the bottom of the dam. The fall of the water, and the water pressure from the lake, forces the water through the dam and spins turbine generators. Dams are expensive to build, but they also help control flooding, can create a large recreational lake, and can provide fresh water for surrounding towns.
- Run-of-the-river System - In a run-of-the-river system the turbines are spun by the natural flow of the river. These systems have the advantage of not creating a huge lake and flooding the area above the dam. As a result, they have less overall impact on the environment. However, in order to provide continuous electricity, the river they use must stay full throughout the year, as the flow is not regulated by a dam.
- Pumped Storage System - This system is like the storage system except it uses pumps to pump used water back up into the reservoir. The way this works is that during the night, when electricity use is much less, it uses the extra electricity to pump the water back up to the top of the dam and refill the reservoir. This improves the overall efficiency of the hydropower plant.
History of Hydropower
Using rivers to power mechanical devices is not a new concept. Waterpower has been in use for thousands of years. The waterwheel was probably invented in the 1st century BCE. Ancient Romans used it to grind grain. It was widely used throughout the Middle Ages and into modern times. Water turbines were first introduced in 1827. They were used originally for irrigation. Today, water turbines are used almost exclusively to generate electric power. The first hydroelectric power plant was built in Wisconsin in 1882. Since then, many more power plants have been built in the United States including the Hoover Dam in 1936 and the Grand Coulee Dam in 1942.
Using rivers to power mechanical devices is not a new concept. Waterpower has been in use for thousands of years. The waterwheel was probably invented in the 1st century BCE. Ancient Romans used it to grind grain. It was widely used throughout the Middle Ages and into modern times. Water turbines were first introduced in 1827. They were used originally for irrigation. Today, water turbines are used almost exclusively to generate electric power. The first hydroelectric power plant was built in Wisconsin in 1882. Since then, many more power plants have been built in the United States including the Hoover Dam in 1936 and the Grand Coulee Dam in 1942.
Try This!
For a fun and engaging activity on hydropower suitable for preschoolers, you can create a simple waterwheel experiment. Here's how:
Paper plates or sturdy paper cups (2 per child)
Markers, crayons, or paint
Scissors
Hole punch
Wooden skewers or pencils (1 per child)
Tape
Small plastic cups or bowls
Water
Instructions:
Decorate the Paper Plates or Cups:
Give each child two paper plates or sturdy paper cups and art supplies.
Encourage them to decorate the plates or cups with colorful designs, creating their own unique waterwheels.
Prepare the Waterwheel:
Take one paper plate or cup and use scissors to cut out small triangles along the edge, evenly spaced around the circumference. These triangles will create the "blades" of the waterwheel.
Repeat the process with the second paper plate or cup.
Attach the Waterwheel to the Skewer:
Take one decorated paper plate or cup and use a hole punch to make a hole in the center.
Insert a wooden skewer or pencil through the hole, positioning it horizontally to create the axle of the waterwheel.
Secure the waterwheel in place by taping the skewer to the back of the paper plate or cup.
Repeat the process with the second decorated paper plate or cup.
Set Up the Experiment:
Fill small plastic cups or bowls with water and place them on a flat surface, such as a table or countertop.
Position the waterwheel creations next to the cups of water, ensuring that the bottom of the waterwheel is submerged in the water.
Observe and Experiment:
Encourage the children to observe what happens when they gently pour water onto the waterwheel.
Ask questions to prompt exploration, such as:
What happens when you pour more water onto the waterwheel?
Does the waterwheel spin faster or slower?
Can you make the waterwheel spin in the opposite direction?
Discuss Hydropower:
After experimenting with the waterwheels, gather the children to discuss what they learned.
Explain that hydropower is energy derived from the force of moving water, just like how the water made the waterwheel spin.
Emphasize that hydropower is a clean and renewable source of energy that can be used to generate electricity.
Conclusion:
By engaging in this hands-on waterwheel experiment, preschoolers can explore the concept of hydropower in a fun and interactive way. Encourage them to continue exploring and learning about renewable energy sources and their importance for a sustainable future.
For a fun and engaging activity on hydropower suitable for preschoolers, you can create a simple waterwheel experiment. Here's how:
- Title: Waterwheel Fun: Exploring Hydropower
Paper plates or sturdy paper cups (2 per child)
Markers, crayons, or paint
Scissors
Hole punch
Wooden skewers or pencils (1 per child)
Tape
Small plastic cups or bowls
Water
Instructions:
Decorate the Paper Plates or Cups:
Give each child two paper plates or sturdy paper cups and art supplies.
Encourage them to decorate the plates or cups with colorful designs, creating their own unique waterwheels.
Prepare the Waterwheel:
Take one paper plate or cup and use scissors to cut out small triangles along the edge, evenly spaced around the circumference. These triangles will create the "blades" of the waterwheel.
Repeat the process with the second paper plate or cup.
Attach the Waterwheel to the Skewer:
Take one decorated paper plate or cup and use a hole punch to make a hole in the center.
Insert a wooden skewer or pencil through the hole, positioning it horizontally to create the axle of the waterwheel.
Secure the waterwheel in place by taping the skewer to the back of the paper plate or cup.
Repeat the process with the second decorated paper plate or cup.
Set Up the Experiment:
Fill small plastic cups or bowls with water and place them on a flat surface, such as a table or countertop.
Position the waterwheel creations next to the cups of water, ensuring that the bottom of the waterwheel is submerged in the water.
Observe and Experiment:
Encourage the children to observe what happens when they gently pour water onto the waterwheel.
Ask questions to prompt exploration, such as:
What happens when you pour more water onto the waterwheel?
Does the waterwheel spin faster or slower?
Can you make the waterwheel spin in the opposite direction?
Discuss Hydropower:
After experimenting with the waterwheels, gather the children to discuss what they learned.
Explain that hydropower is energy derived from the force of moving water, just like how the water made the waterwheel spin.
Emphasize that hydropower is a clean and renewable source of energy that can be used to generate electricity.
Conclusion:
By engaging in this hands-on waterwheel experiment, preschoolers can explore the concept of hydropower in a fun and interactive way. Encourage them to continue exploring and learning about renewable energy sources and their importance for a sustainable future.
Or This...Weather Permiting!!!
Materials Needed:
Water hose with a spray nozzle
Various lightweight and heavy objects (e.g., small plastic toys, balls, rocks)
Flat surface for experimentation (e.g., outdoor pavement or sidewalk)
Optional: Bucket or basin to catch water runoff
Measuring tape or ruler
Instructions:
Introduction to Hydropower:
Begin by introducing the concept of hydropower to the children. Explain that hydropower is a renewable energy source that uses the force of moving water to generate electricity.
Predictions and Hypotheses:
Before starting the experiment, gather the preschoolers and ask them to make predictions about what will happen when they use the water hose to move different objects.
Encourage them to form hypotheses based on their predictions, relating them to the concept of hydropower. For example, "I think the water will move the lighter objects faster because they are easier to push, just like how water turns turbines to make electricity."
Experiment with Water Pressure:
Invite the preschoolers to take turns aiming the spray nozzle at different objects and observing what happens.
Encourage them to experiment with the distance and angle of the spray to see how it affects the movement of the objects.
Measurement and Data Collection:
After each trial, have the children measure the distance each object traveled using a measuring tape or ruler.
Record the measurements and observations on a chart or graph.
Discussion on Hydropower:
Gather the preschoolers to discuss their observations and compare them to their predictions and hypotheses.
Relate their findings to the concept of hydropower by discussing how moving water can be used to turn turbines, which generate electricity.
Ask questions like "How is the water in the hose similar to the water in a river or dam used for hydropower?" and "How can we use the energy from moving water to do work, like moving objects?"
Extension Activity:
Encourage the children to think of ways to harness the energy from moving water in their everyday lives, such as using waterwheels or turbines to power toys or small devices.
Conclusion:
Through the water hose challenge, preschoolers can explore the principles of hydropower and renewable energy in a hands-on and engaging way. Encourage them to continue experimenting, making predictions, and asking questions as they discover the wonders of science and engineering.
- Title: Hydropower Exploration: Water Hose Challenge
Materials Needed:
Water hose with a spray nozzle
Various lightweight and heavy objects (e.g., small plastic toys, balls, rocks)
Flat surface for experimentation (e.g., outdoor pavement or sidewalk)
Optional: Bucket or basin to catch water runoff
Measuring tape or ruler
Instructions:
Introduction to Hydropower:
Begin by introducing the concept of hydropower to the children. Explain that hydropower is a renewable energy source that uses the force of moving water to generate electricity.
Predictions and Hypotheses:
Before starting the experiment, gather the preschoolers and ask them to make predictions about what will happen when they use the water hose to move different objects.
Encourage them to form hypotheses based on their predictions, relating them to the concept of hydropower. For example, "I think the water will move the lighter objects faster because they are easier to push, just like how water turns turbines to make electricity."
Experiment with Water Pressure:
Invite the preschoolers to take turns aiming the spray nozzle at different objects and observing what happens.
Encourage them to experiment with the distance and angle of the spray to see how it affects the movement of the objects.
Measurement and Data Collection:
After each trial, have the children measure the distance each object traveled using a measuring tape or ruler.
Record the measurements and observations on a chart or graph.
Discussion on Hydropower:
Gather the preschoolers to discuss their observations and compare them to their predictions and hypotheses.
Relate their findings to the concept of hydropower by discussing how moving water can be used to turn turbines, which generate electricity.
Ask questions like "How is the water in the hose similar to the water in a river or dam used for hydropower?" and "How can we use the energy from moving water to do work, like moving objects?"
Extension Activity:
Encourage the children to think of ways to harness the energy from moving water in their everyday lives, such as using waterwheels or turbines to power toys or small devices.
Conclusion:
Through the water hose challenge, preschoolers can explore the principles of hydropower and renewable energy in a hands-on and engaging way. Encourage them to continue experimenting, making predictions, and asking questions as they discover the wonders of science and engineering.
|
|
|
|
|
|
Learn more...
- Energy Kids: Hydropower
- Renewable Energy Project for Kids: Power from Water
- Teach Engineering-Water Power
- Energy.gov-Hydropower Educational Resources To Get Energy Flowing
- Wave and Tidal Energy