1. Earth’s Energy Sources
Chapter 22 Pearson, 16 Glenco

2. Energy uses
List all of the energy sources you have used today

3. Solar Energy Heating with solar energy Passive Solar energy
Active Solar energy

4. Passive

5. Active

6. Transforming Energy
Law of conservation of Energy: energy is neither created nor destroyed only transformed.
Some energy transformation is not useful for us.
Example: Power lines transform energy into heat.
Published January 27, 2011 | By Amanda Kaufmann

7. Energy Usage in the United States

8. Energy Usage in the United States

10. Fossil Fuels Formed by decay of ancient plants and animals
When burned they produce carbon dioxide and water
Petroleum,
Natural Gas, and coal

11. Petroleum Fossil Fuel made of Hydrocarbons
Produced by separating the liquid oil in a process called Fractional distillation.
Oil is pumped into the bottom of a tower and heated. Materials rise to the top depending on boiling point and are collected. Some are pulled from the bottom, like asphalt.
Other uses: Plastics, lubricants, asphalt

12. Petroleum and by-products
List four things in the class room made from petroleum.

13. Natural Gas Composed mainly of Methane.
Natural gas contains more energy per kilogram than either petroleum or coal.
Produces fewer pollutants than other fossil fuels

14. Coal Solid fossil fuel found underground
One fourth of our energy comes from coal.
Coal is formed from organic material deposited in ancient swamps.
Burning coal results in more pollutants

15. Generating Electricity

16. Coal generation

17. Electricity Generation
Fuel is burned to heat a boiler of water
Steam is produced and causes the turbine to spin
Turbine is connected to an electric generator
Electric current is produced when the spinning turbine shaft rotates magnets inside the generator.

18. Simple Electric Generator
When the coil is turned, the magnets cause movement in the electrons within the coil.
The movement of
electrons causes
an electric current.

19. Efficiency of Power plants
Process
Efficiency %
Chemical Thermal
60 %
Water steam
90%
Steam turn turbine
75%
Turbine generator
95%
Tranmission through power lines
Over all efficiency
35%
65% is converted to thermal( unusable energy)

20. Nonrenewable Resources
Cannot be replaced by natural processes as quickly as they are used.
All fossil fuels are nonrenewable.

21. Carbon dioxide
According to the graph by how many parts per million (ppm) did the concentration of CO2 increase from 1958 to 2000?

22. Nuclear Energy

23. Nuclear Power
Energy is released when the nucleus of an atom breaks apart.
Nuclear power plants produced 8% of all power in 2003.
There were 104 nuclear reactors at 65 power plants in the US.

24. Core of the Nuclear Reactor

25. Nuclear power Only certain elements
Uranium 235
Naturally occurring at 0.7% so it is enriched to 3-5%
Inside the reactor core fuel pellets are placed in a tube the core contains 100,000 Kg of uranium in fuel rods
Energy released by 1 gram = 3 million kg of coal

26. Nuclear fission
A neutron hits a U-235 nucleaus and splits it apart into two smaller nuclei and energy is released

27. Risks of Nuclear power Mining of Uranium causes enviornmental damage.
Coolant water must be cooled before discharge
The most serious is the release of radioactivity

28. Disposal of Nuclear waste
Low-level waste:
Have low radioactivity
Short half-lives
Can be released into the air when diluted.

29. High-Level Waste: The spent fuel rods Stored in water
Will remain radioactive for for tens of thousands of years
Can be sealed in glass and buried in salt mines.

30. Renewable Energy Resources
A Renewable resource is an energy source that is replaced nearly as quickly as it is used

31. Solar
Use Photovoltaic cell that converts radiant energy from the Sun directly into electrical energy. Also called solar cells

32. How a photovoltaic cell works
Only about 7 to
11% efficient

33. Uses of Solar energy More expensive in 2003 than burning fossil fuels
Another method is to use the sun to heat a fliud that then heats steam toturn a turbin to generate power.

34. Hydroelectric power
Electricity is produced by the energy of moving water

36. Advantages of Hydro power
8% of all US power is made this way
Efficient: because no heat is involved that can take away from the energy used to turn the turbines
Without any pollution
Dams form lakes that can be used for drinking water and irrigation

37. Disadvantages
Have to have a place to build the dam near the regions that need to power
Destroys the area around the dam
Fish cannot migrate
Fish ladders are added to dams but still reduce the fish.

38. Tidal Energy
Gravity from the sun and moon bulge the earths oceans (tides)
Hydroelectric power can be generated by the tides. As the tide comes in and out it turns a turbine
Pollution free
Only a few places have large enough tides to produce electricity

39. Wind Energy Windmills historically pump water, grind grain.
For electricity they are 20% efficient( and improving)
Only a few places have enough wind
Noisy
Change landscape appearance, disrupt bird migrations.
They do not consume any nonrenewable resource and do not pollute

40. Geothermal energy Energy from the earth. 16% efficient
Can release gases and bring brine to the surface
Only can be used where magma is close to the surface.

42. Alternative fuels
Biomass fuels; burned in the presence of oxygen: wood sugarcane, fibers, rice hulls, animal manure.
Hydrogen gas fuel cells