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Chapter Introduction Lesson 1 Sources of Energy Lesson 2 People and the Environment Lesson 3 Saving Resources Chapter Wrap-Up
Chapter Introduction
Lesson 1 Sources of Energy
Lesson 2 People and the Environment
Lesson 3 Saving Resources
Chapter Wrap-Up
Where do the materials and sources of energy that people use come from?
Essential Question
• What are the ways electricity can be produced?
Sources of Energy
Renewable resources
Nonrenewable resources
Inexhaustible resources
Fossil fuels
Sources of Energy
Alternative energy source
Nuclear energy
Geothermal energy
Hydroelectricity
• Natural resources are materials people take from Earth.
• One way scientists organize Earth’s natural resources is by the time needed to produce them.
What are renewable resources?
• Renewable resources are materials from the environment that people use that can be replaced relatively quickly.
– Ex. Solar energy, Heat
What are renewable resources? (cont.)
• Nonrenewable resources are materials from the environment that people use that cannot be replaced.
– Ex. Coal, copper
What are renewable resources? (cont.)
• Sometimes a renewable resource can be used up more quickly than it can be replaced.
– Ex. Trees – (deforestation)
What are renewable resources? (cont.)
• Inexhaustible resources is an energy source that cannot be used up.
– Ex. Sunlight, wind, water
• However, the quality of an inexhaustible resource can change.
– Ex. Water – drinking water supplies can become so polluted that they are no longer usable.
What are renewable resources? (cont.)
• Rocks and minerals are also natural resources.
– Ex. Minerals: quartz, mica and feldspar make up granite (a hard rock)
What are renewable resources? (cont.)
• Most rocks and minerals are expensive to obtain and limited in supply. Therefore, they are classified as nonrenewable resources.
• However, a few minerals such as quartz are so abundant and common they are considered to be inexhaustible.
What are renewable resources? (cont.)
• Soil is a mixture of weathered rock, decayed plant, animal remains and water.
• People depend on soil to grow food.
– In some places it can take hundreds or thousands of years for soil to form.
What are renewable resources? (cont.)
About 93 percent of the energy used in the United States comes from nonrenewable energy resources—fossil fuels and nuclear energy.
What are renewable resources? (cont.)
• The energy used when you ride in a car, turn on a light or use an electric appliance usually comes from burning fossil fuels.
• Fossil fuels are a fuel formed from the decay of ancient forms of life.
– Ex. Coal, oil and natural gas
How do we get energy from fossil fuels?
• Coal was formed from the remains of ancient plants that lived in swamps.
• Oil and natural gas were made from the remains of microscopic organisms that lived in oceans millions of years ago.
How do we get energy from fossil fuels? (cont.)
• Geologic processes buried these dead organisms under layers of sediment and rock. High temperature and pressure changed them into oil and natural gas.
How do we get energy from fossil fuels? (cont.)
• The chemical potential energy stored in fossil fuels changes to thermal energy when fossil fuels burn.
How do we get energy from fossil fuels? (cont.)
• This coal-burning electric power plant transforms chemical energy stored in a fossil fuel into electric energy.
How do we get energy from fossil fuels? (cont.)
• Fossil fuels are nonrenewable resources. With the growth of industry, the demand for energy also grows.
• Without fossil fuels, the economy would suffer.
How do we get energy from fossil fuels? (cont.)
• Alternative energy source is a source of energy other than the burning of fossil fuel.
– Ex. Energy from atoms, heat inside the Earth, the Sun, moving water, and wind.
What are alternative energy sources?
• Nuclear energy is the energy contained in the nucleus of an atom.
– In nuclear power plants, breaking apart uranium nuclei transforms nuclear energy into thermal energy.
What are alternative energy sources? (cont.)
• A nuclear power plant transforms nuclear energy into electric energy.
What are alternative energy sources? (cont.)
• Solar energy is energy from the Sun.
– Sunlight is converted directly to electrical energy in a device called a photovoltaic cell.
– Solar panels are made of many individual photovoltaic cells.
What are alternative energy sources? (cont.)
• Electric current flows from the solar panel to objects in the home that use electricity and back to the solar panel in a complete circuit.
What are alternative energy sources? (cont.)
• Geothermal energy is heat from below the Earth’s surface.
• In some places where magma is close to the surface, groundwater – water that fills the cracks and pore spaces in rock – gets extremely hot.
– This deep, hot groundwater is called a geothermal reservoir.
What is geothermal energy?
• A geothermal power plant transforms the thermal energy from inside Earth into electric energy.
What is geothermal energy? (cont.)
• Geothermal energy helps keep the temperature of the ground at a depth of several meters at a nearly constant temperature.
What is geothermal energy? (cont.)
• This constant temperature can be used to cool and heat buildings by using a heat pump.
What is geothermal energy? (cont.)
• Hydroelectricity is electricity generated by running water.
• Most hydroelectricity is generated at hydroelectric dams.
How is water used to generate electricity?
• A hydroelectric power plant converts the potential energy of the water stored behind the dam to electric energy.
How is water used to generate electricity? (cont.)
• The constant motion of the ocean is an inexhaustible source of mechanical energy that can be converted to electrical energy.
• Coastal areas that have great differences between high and low tides – regular rise and fall of the water level along a shore – can be a source of tidal power.
How is water used to generate electricity? (cont.)
How is water used to generate electricity? (cont.)
How can we get energy from the wind? • Wind energy is another inexhaustible
energy resource.
• Modern wind turbines convert the kinetic energy in wind into electric energy.
A. nonrenewable energy resource
B. renewable energy resource
C. inexhaustible energy resource
D. alternative energy resource
What is the term for an energy resource that is available in limited amounts or that is used faster than it is replaced?
A. solar energy
B. hydroelectric power
C. geothermal energy
D. fossil fuels
What is the name for thermal energy that comes from inside Earth?
A. wood
B. oil
C. coal
D. natural gas
Which is not a fossil fuel?
Essential Question
• How does using natural resources affect the environment?
People and the Environment
Pollution
Smog
Acid rain
Thermal pollution
People and the Environment
Monetary costs
Nonmonetary costs
Cost-effectiveness
• Pollution is a harmful change to the environment.
• The production and use of energy is a leading source of pollution.
How does energy use affect the environment?
How does energy use affect the environment? (cont.)
How does energy use affect the environment? (cont.)
• Smog is a mixture of smoke and fog, formed when smoke and fumes collect in moist, calm air.
– Smog irritates the eyes, nose and throat.
How does energy use affect the environment? (cont.)
• Acid rain is acid that is formed when the sulfur and nitrogen gases produced by burning fossil fuels combine with water vapor in the air and then fall to Earth as rain.
– Acid rain can pollute water and soil, kill plants and fish, and damage the stone and metal used in buildings and statues.
How does energy use affect the environment? (cont.)
• Whether electricity is generated by burning fossil fuels or using nuclear or geothermal energy, thermal pollution is produced.
– Thermal pollution is the addition of warm water into a stream or lake that is normally cold.
• Important factors in deciding which energy source to use are the costs and benefits of the energy.
• Monetary cost is the cash value of energy use: examples include the cost of heating a home or the large amount of money used to clean up an oil spill.
How does cost affect energy use?
• Nonmonetary cost is the environmental consequences of energy use; examples include the generation of pollution and long-term health problems caused for people.
– Ex. Surface mining – is much safer and less expensive than underground mining but it destroys ecosystems by removing soil, destroying forests and adding dust to the air.
How does cost affect energy use? (cont.)
• Cost-effectiveness is a measure determined by comparing the costs and the consequences of different ways of doing something.
– The source that is the least expensive and causes the least damage to the environment is the most cost-effective.
How does cost affect energy use? (cont.)
• Currently, many alternative energy sources are less cost-effective than fossil fuels.
– Technology needed to deliver energy from them is expensive. (It is cheaper to drill for oil than to build solar panels).
– Alternative sources also produce less usable energy than fossil fuels.
How does cost affect energy use? (cont.)
• Nonmonetary cost can lead to monetary costs.
– Expense of repairing or cleaning up environmental damage.
• Ex. Oil spills in the ocean can disrupt the life cycle of some fish can affect jobs in the fishing industry and increase the cost of food as well as the cost of cleaning up the spill.
How does cost affect energy use? (cont.)
What are the disadvantages of using renewable resources?
A. efficiency
B. monetary costs
C. cost-effectiveness
D. nonmonetary costs
Which is determined by comparing the expense and consequences of doing something?
A. wind energy
B. solar energy
C. geothermal energy
D. coal
Which of these energy sources causes the most pollution?
Essential Question
• How does conservation preserve resources and the environment?
Saving Resources
Conservation
Biomass
Hydrogen fuel
Saving Resources
Reduce
Reuse
Recycle
• Earth’s resources are precious. If resources are used up too quickly, people will not have as many options for energy sources in the future.
• Conservation is saving, protecting, or using natural resources wisely.
What is conservation?
• Soil conservation
– Adding decomposed organic material to the soil to replace minerals removed by the crops.
– Rotating the crops each year to prevent the same nutrients being pulled from the soil.
What is conservation? (cont.)
• Soil conservation (cont.)
– Plant crops in steps to prevent soil from being washed or blown away. This helps in periods of droughts (lack of precipitation for an extended period of time).
– No till planting protects the soil during winter but the possible use of pesticides may contaminate drinking waters.
What is conservation? (cont.)
• Fossil fuels will eventually be used up. We must understand how to conserve them.
• Vampire energy is the energy used by electronic devices such as computers, televisions and appliances that are plugged in 24 hours a day, even though they are turned off.
How can we reduce the burning of fossil fuels?
• You can conserve energy by:
How can we reduce the burning of fossil fuels? (cont.)
• Use of alternative energy sources can reduce the use of fossil fuels:
– Biomass is the resource that comes from living or recently living organisms.
• Biomass can be processed to make liquid fuels, known as biofuels – Ex. Ethanol
How can we reduce the burning of fossil fuels? (cont.)
– Methane is produced in nature as organic matter decays. Decomposing waste in landfills and manure in livestock yards produce methane the can be collected and used as fuel.
– Hydrogen fuel is hydrogen gas burned as an energy source.
• Hydrogen gas is very abundant. Water vapor is the only waste product in burning hydrogen fuel but production requires large amounts of energy.
How can we reduce the burning of fossil fuels? (cont.)
• 50% of Louisiana is covered by forests. Louisiana’s forests support many wood-using industries.
• Protection of this valuable renewable resource is done through forestry management.
– Growing trees on a tree farm. When the trees are harvested on a tree farm, the seeds are replanted and trees are regrown without harming the natural resources.
How does Louisiana conserve its natural resources?
• Louisiana also has a thriving fishing industry.
• One way Louisiana conserves the number of fish in its water ecosystems is by farming fish.
– Fish farms have been built to raise and harvest fish and crustacean populations, this technique is called aquaculture.
How does Louisiana conserve its natural resources?
• Reduce is to use less of something.
• Reuse is to use something again.
• Recycle is to make new objects or materials from old objects or materials.
What are the 3 Rs?
A. acid rain
B. carbon dioxide
C. carbon monoxide
D. water vapor
Cars that run on hydrogen fuel emit
A. Turn off lights in an empty room.
B. Throw away an aluminum can.
C. Ignore a leaky faucet.
D. Leave a computer on when it is not being used.
Which is a way to conserve resources?
Visual Summary
Chapter Review
Standardized Test Practice
Earth provides many valuable natural resources. Almost everything people use comes directly or indirectly from a natural resource. Using these resources affects the environment and the economy. However, people can use these resources wisely to minimize their impact.
• Resources are classified by how much time is needed to produce them.
• Fossil fuels are nonrenewable resources. They take a long time to replace or cannot be replaced at all.
• Renewable resources can be replaced relatively quickly.
• Energy resources that are not fossil fuels are alternative energy sources.
Lesson 1: Sources of Energy
Lesson 2: People and the Environment• Using fossil fuels can cause smog and acid
rain.
• Using energy resources has monetary costs and nonmonetary costs.
• Each different energy resource affects the environment and the economy in some way.
• Earth’s land, water, and air can be protected by practicing conservation.
• Different practices help conserve the land, water and air. Using alternative energy sources will help reduce the use of fossil fuels.
• Practicing the 3 Rs will also help preserve Earth’s resources and protect the environment.
Lesson 3: Saving Resources
A. electrical to hydroelectric
B. geothermal to thermal
C. solar to electrical
D. hydroelectric to mechanical
Photovoltaic cells perform which type of energy transformation?
A. coal
B. solar
C. wind
D. hydroelectricity
Which is a nonrenewable source of energy?
A. wind
B. biomass
C. sunlight
D. minerals and rocks
Which resource is renewable but can be made unusable if not managed properly?
A. biomass
B. geothermal
C. nuclear power
D. hydroelectric power
Which energy source produces radioactive waste?
A. exhaustible energy resource
B. renewable energy resource
C. inexhaustible energy resource
D. nonrenewable energy resource
What term refers to an energy resource that cannot be used up?
A. 3 percent
B. 7 percent
C. 17 percent
D. none
Approximately how much pollution comes from a hydrogen fuel car?
A. crops
B. minerals
C. streams
D. trees
Which is a nonrenewable land resource?
A. More acid rain is produced.
B. Less waste ends up in landfills.
C. More trees are cut down.
D. More fossil fuels are discovered.
How does recycling products help the environment?
A. Petroleum
B. Coal
C. Natural gas
D. Nuclear power
Which is the most used nonrenewable energy resource in the United States?
A. solar energy
B. hydroelectric energy
C. fossil fuels
D. inexhaustible energy resources
What are the remains of ancient organisms that can be burned as an energy source?
