Unit C Lesson C9 Solar Energy
Completion requirements
Lesson C9: Solar Energy: A Good Choice?
Video Lesson
How do solar panels work? Watch this video to learn more about how humans harness energy from the Sun.
Lesson C9: Solar Energy: A Good Choice?
Figure C.3.9.1– Silicon is a shiny mineral that conducts electricity well.
Figure C.3.9.2– Silicon is an important material in computer chips and solar panels.
Silicon
Silicon is an essential mineral for modern human electronics. It is one of the most common minerals on Earth, which makes it inexpensive and easy to obtain. Pure silicon is shiny and silver, but it is not a metal. Silicon is a semiconductor, which is a substance that can conduct electricity under some conditions but not under others. Therefore, it is good medium for the control of electrical current because its ability to conduct electricity can be increased or decreased. This property makes silicon ideal for constructing tiny electrical circuits on computer chips. The same property makes silicon useful in solar panels. When solar energy meets silicon in a solar cell, electricity starts flowing.
Silicon is an essential mineral for modern human electronics. It is one of the most common minerals on Earth, which makes it inexpensive and easy to obtain. Pure silicon is shiny and silver, but it is not a metal. Silicon is a semiconductor, which is a substance that can conduct electricity under some conditions but not under others. Therefore, it is good medium for the control of electrical current because its ability to conduct electricity can be increased or decreased. This property makes silicon ideal for constructing tiny electrical circuits on computer chips. The same property makes silicon useful in solar panels. When solar energy meets silicon in a solar cell, electricity starts flowing.
Reading and Materials for This Lesson:
Science in Action 7
Materials:
Science in Action 7
Reading: Pages 224–228
Materials:
No other materials are required for this lesson.
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Silicon
Watch this video to learn more about silicon.
Watch this video to learn more about silicon.
Fusion
Fusion is a process that produces the Sun’s energy. The Sun contains mostly hydrogen gas and helium gas. Fusion occurs when hydrogen particles join to make helium particles. In the process of fusion, large amounts of heat and light are released. The Sun’s surface is extremely hot at 5500o C. Ouch!
Fusion occurs also in distant stars. When you look at the sky on a clear night, you can see small pinpoints of light from fusion in far-away stars.
Fusion is a process that produces the Sun’s energy. The Sun contains mostly hydrogen gas and helium gas. Fusion occurs when hydrogen particles join to make helium particles. In the process of fusion, large amounts of heat and light are released. The Sun’s surface is extremely hot at 5500o C. Ouch!
Fusion occurs also in distant stars. When you look at the sky on a clear night, you can see small pinpoints of light from fusion in far-away stars.
Figure C.3.9.3– Fusion releases large amount of energy in the Sun.
Figure C.3.9.4– Fusion produces heat and light in stars.
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Fusion
Watch these two videos to learn more about fusion in the Sun.
Watch these two videos to learn more about fusion in the Sun.
Connections
Connections: Technology
>> Solar Innovations
Researchers and inventors are very interested in finding ways to use solar energy. Solar energy has several advantages not in other sources of energy.
Because the Sun produces energy from fusion continually, solar energy is a renewable resource. Solar energy will not be depleted for billions of years, which is unlike chemical energy from fossil fuels. Another advantage of solar energy is that it does not release carbon dioxide into the atmosphere, a major contributor to climate change.
People around the world are designing ways to harness energy from the Sun so we can use such methods in technologies that meet our modern daily needs.
>> Solar Innovations
Researchers and inventors are very interested in finding ways to use solar energy. Solar energy has several advantages not in other sources of energy.
Because the Sun produces energy from fusion continually, solar energy is a renewable resource. Solar energy will not be depleted for billions of years, which is unlike chemical energy from fossil fuels. Another advantage of solar energy is that it does not release carbon dioxide into the atmosphere, a major contributor to climate change.
People around the world are designing ways to harness energy from the Sun so we can use such methods in technologies that meet our modern daily needs.
Watch More
Solar Innovations
Watch this video to learn how large solar power plants generate electricity.
Watch this video to learn how large solar power plants generate electricity.
Watch this video to see a boat that runs completely on solar power.
Solar Energy Use
If humans are capable of capturing renewable solar energy through solar cells, then why isn’t solar energy our only source of energy?
The amount of sunlight reaching Earth changes, depending on the cloud cover. When skies are cloudy, less electricity is generated in solar panels. Currently, batteries that store solar-generated electricity on sunny days are not totally effective. Due to unpredictable weather and the lack of effective batteries, solar-generated electricity is unreliable. This is a problem that researchers and inventors are trying to solve.
Other sources of energy must help to keep the electricity supply constant so we can use electricity without interruption.
If humans are capable of capturing renewable solar energy through solar cells, then why isn’t solar energy our only source of energy?
The amount of sunlight reaching Earth changes, depending on the cloud cover. When skies are cloudy, less electricity is generated in solar panels. Currently, batteries that store solar-generated electricity on sunny days are not totally effective. Due to unpredictable weather and the lack of effective batteries, solar-generated electricity is unreliable. This is a problem that researchers and inventors are trying to solve.
Other sources of energy must help to keep the electricity supply constant so we can use electricity without interruption.
Figure C.3.9.5– Solar power plants generate electricity with solar towers.
Figure C.3.9.6– Large mirrors focus light on a solar tower.
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Solar Energy Use
Watch this video to learn more about the limits of using solar power.
Watch this video to learn more about the limits of using solar power.
New solar panels have improvements that help them absorb more light on cloudy days. Watch this video to learn more.
Connections
Connections: Technology
>> Solar Power in the Developing World
Solar energy is an excellent innovation for developing countries that do not have large electric power plants and transmission lines to transport electricity to remote areas. Solar panels are more portable and small-scale than other forms of electricity generation.
Electricity and heat are necessary for people in rural areas. Electricity produces light and power to run important technologies, such as medical and communications equipment. Many people in developing countries still do not have easy access to clean drinking water. Heat energy from solar power is one method of treating water so that it is safe to drink.
>> Solar Power in the Developing World
Solar energy is an excellent innovation for developing countries that do not have large electric power plants and transmission lines to transport electricity to remote areas. Solar panels are more portable and small-scale than other forms of electricity generation.
Electricity and heat are necessary for people in rural areas. Electricity produces light and power to run important technologies, such as medical and communications equipment. Many people in developing countries still do not have easy access to clean drinking water. Heat energy from solar power is one method of treating water so that it is safe to drink.
Figure C.3.9.7– Solar panels are helpful in countries that do not have other reliable sources of electricity.
Figure C.3.9.8– Solar panels produce electricity in isolated rural areas.
Watch More
Solar Power in the Developing World
This video explains the invention of a “solar suitcase” to produce electricity for remote hospitals in Africa.
This video explains the invention of a “solar suitcase” to produce electricity for remote hospitals in Africa.
Some researchers are determining how to turn water directly into steam from solar energy. Heat kills harmful bacteria in drinking water, which prevents people from getting sick. Watch these two videos to learn more.
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