1. Chapter 12: Conserving Resources
SPI

2. Ch. 12 Section 1 Learning Objectives
Compare renewable resources and nonrenewable resources
List uses of fossil fuels
Identify alternatives to fossil fuel use
Main idea: Earth has natural resources that can be replenished as well as natural resources that cannot be replenished.

3. New Vocabulary Natural resource Renewable resource
Nonrenewable resource
Petroleum
Fossil fuel
Hydroelectric power
Nuclear energy
Geothermal energy

4. Natural Resources
Natural resources are those parts of the environment that are useful or necessary for the survival of living organisms.
What kind of natural resources do you use?
Food, air, water?
Natural resources also supply energy for automobiles & power plants
Some resources are plentiful and some are not

5. Renewable Resources
A renewable resource is any natural resource that is recycled or replaced constantly by nature.
The sun supplies a constant supply of heat & light
Rain fills lakes and streams with water
Plants carry out photosynthesis and put oxygen back into the air

6. Renewable Resources
Renewable resources can be recycled or replaced, but they are in short supply (sometimes)
Rain may not refill lakes, rivers, or streams and water may become short in supply
In desert regions water and other resources are scarce

7. Nonrenewable Resources
Natural resources that are used up more quickly than they can be replaced by natural processes are nonrenewable resources.
Earth’s supply of these is limited
Plastics, paints, and gasoline are made from an important nonrenewable resource called petroleum
formed mostly from remains of microscopic marine organisms buried in Earth’s crust.
It takes hundreds of millions of years to form

8. Nonrenewable Resources
Minerals and metals found in Earth’s crust are also nonrenewable
What are some nonrenewable resources you can think of?
Petroleum, diamond, graphite, iron, copper, tin, gold, silver, tungsten, uranium
Many, many manufactured items are made from nonrenewable resources (cars, homes, etc…)

9. Fossil Fuels
Coal, oil, and natural gas are some nonrenewable resources that supply energy.
Fossil fuels are fuels formed in Earth’s crust over hundreds of millions of years
All types of transportation that use gasoline, diesel fuel, and jet fuel use oil
Coal is used in power plants to produce electricity
Natural gas is used in manufacturing for heating, cooking, and sometimes fuel

10. Problems with Fossil Fuels
We all use fossil fuels everyday
Earth’s supply of fossil fuels is limited
They may become expensive and difficult to obtain in the future
Using fossil fuels may cause environmental problems
Mining coal strips away thick layers of soil and rock which destroys ecosystems
Burning fossil fuels produces waste gases that cause pollution

11. Conserving Fossil Fuels
How can we conserve fossil fuels?
Turn lights, appliances, etc off when not using
Reduces electricity, which is produced in power plants that fossil fuels
Taking public transportation or riding in car pools reduces exaust
Walking or riding bicycles

12. Alternatives to Fossil Fuels
Developing alternative uses to fossil fuels is also a way to conserve
Using water, wind, and solar or atomic energy is an alternative
Wind and solar energy are so plentiful that they are considered inexhaustible resources

13. Alternatives to Fossil Fuels
Water
Wind
Solar
Nuclear
Geothermal

14. Water Power
Water is a renewable energy source that can be used to generate electricity
Hydroelectric power is electricity that is produced when the energy of falling water is used to turn turbines of an electric generator
Does not produce any pollution
It does however, produce environmental concerns
Requires the building of a dam so water levels can be raised
Many acres behind the dam are flooded

15. Hoover Dam

16. Wind Power
Wind power is another resource that is renewable and can be used to produce electricity
Wind turns the blades of a turbine
Turbine powers an electric generator
If winds blow at least 32km/h electricity produced
Does not cause air pollution

17. Nuclear Power Makes use of the nuclei of atoms
Nuclear energy is released when billions of atomic nuclei from uranium are split apart in a nuclear fission reaction
Energy is used to produce steam that rotates the turbine blades of an electric generator
Does not contribute to pollution
Uranium is a nonrenewable resource and mining can disrupt ecosystems
Nuclear power plants also produce radioactive waste that can harm living organisms

19. Geothermal Energy
The hot, molten rock deep beneath Earth’s surface is a source of energy, also
Geothermal energy is heat energy generated deep within earth that is available only where geysers or volcanoes are located
Geothermal power plant in California uses steam produced by geysers
Island nation of Iceland was formed by volcanoes and geothermal energy is plentiful
About 90% of homes get their electricity by geothermal energy

20. Solar Energy Most inexhaustible source of energy on Earth
Another alternative to fossil fuels
In the northern hemisphere parts of buildings (that face south) receive large amounts of sunlight through very large windows
Floors and walls are made of materials that absorb heat during the day
During the night the stored heat is released slowly, keeping the building warm

21. Solar Energy
How do solar powered calculators and spacecrafts use the sun for electricity?
Use cells (photovoltaic) to turn sunlight into electric current
PV cells are small and easy to use
Only produce energy in light
Batteries must also be used in darkness
PV cells are too expensive for generating large amounts of electricity
Improvements are being made to make them more widely available

22. What have you learned? What are natural resources?
Compare and contrast nonrenewable and renewable resources.
Describe advantages and disadvantages of using nuclear power.
Describe two ways solar power can be used to reduce fossil fuel use.