1. Fossil FuelsOSSIL
FUELS
85% of the world’s
commercial energy
COAL
NATURAL GAS
OIL

2. Generating Electricity
For many years, we have generated electricity in much the same way:

3. Fossil Fuels
• Fossil fuels are forms of stored solar energy
– Plants convert solar energy to chemical energy
through photosynthesis
– Incomplete decomposed organic matter then
covered up
– Converted to oil, natural gas, and coal
• Provide 90% of energy consumed

4. These fuels were dug out of the ground. They had taken millions of
years to make and so are called FOSSIL FUELS and are NONRENEWABLE.
COAL
Made from the remains of plants
which died millions of years ago

5. Coal
• Classified according to its energy and sulfur
content
–
–
–
–
Anthracite
Bituminous
Subbituminous
Lignite
• Energy content greatest in anthracite and lowest in
lignite
• Lower sulfur coal (Lignite) emits less sulfur
dioxide

8. Coal cheaper,
but polluting
Much Eastern U.S. coal has
high-sulfur content,
more expensive to mine
Much Western U.S. coal has
low-sulfur content,
cheaper to mine
But mining in semi-arid West
more damaging to land.

9. Effects on health
• Black Lung Disease
(miners)
• Respiratory
illnesses
(public)

10. Effects on land
• Coal sludge releases
• Hardpan at strip mines
• Mountaintop removal
• Huge water use
– Slurry pipelines

11. Effects on air
• Greenhouse gases
– 3/4 sulfur dioxide
– 1/3 nitrogen oxides
– 1/2 carbon dioxide
• Toxics
– Mercury
– Uranium

12. Energy lost from coal
65% wer plants
lost in
power plants
10% lost on
transmission lines
(stray voltage)

13. The Future of Coal
• Burning of coal
– produces 60% of electricity used and
– 25% of total energy consumed in US
• Coal 90% of our energy reserves

14. The Future of Coal
• Clean Air Amendments of 1990 mandate reducing
these emissions.
• Option for cleaner coal include:
– Chemical and/or physical cleaning of coal prior to
combustion.
– New boiler designs that permit lower temp of
combustion.
– Injection of material rich in calcium carbonate into the
gases following burning.
• Scrubbers-removes sulfur dioxides

15. Coal scrubbers

16. The Future of Coal
– Conversion of coal at power plants into gas
before burning.
– Convert coal to oil.
– Consumer education about energy conservation
and efficiency to reduce the demand for energy.
– Development of zero emissions coal-burning
electric power plants

17. NATURAL GAS
Methane, other
Gases in bedrock

18. OIL and NATURAL GAS (Methane)
Made from the decayed remains of sea creatures
which died millions of years ago

20. Advantages of natural gas
• Cleaner to burn
– Half as much CO2 as coal
• More efficient
– 10% energy lost
• Provides energy independence for
the U.S.

21. Disadvantages of natural gas
• Difficult to transport
– Pipelines
– Liquified Natural Gas (LNG) tankers
• Can be polluting, dangerous when
extracted
-Groundwater contamination
-Earthquakes

22. OIL (PETROLEUM)
Buried organic matter
rich in hydrocarbons

23. Petroleum Production
• Primary production
– Involves simply pumping the oil from wells
– Recovers only 25% of petroleum in reservoir
• Enhanced recovery
– Increase the amount recovered to about 60%
– Steam, water, or chemicals injected into the
reservoir to push oil towards wells

24. Oil in the Twenty-First Century
– For every three barrels of oil we consume, we
are finding only one barrel.
– Forecasts that predict a decline in production of
oil are based on many assumptions but most
expert agree it is coming in the next few
decades.
– In the US production of oil as we know it now
will end by 2090. World production by 2100.

27. Exxon Valdez
• March 24, 1989
• 10.8 gallons
• 1100 miles of Alaskan
coast
• Valdez was carrying 53
million gallons
• Impact on environment

28. Exxon Valdez, Alaska
1989

29. Prince William Sound fishing
industry damaged

30. Deep Water Horizon
•
•
•
•
April 20 – July 15, 2010
Gulf of Mexico, Louisiana
205.8 million gallons
Effectively dead
September 19, 2010

31. Effects on Wildlife

32. OIL SKIMMING
BOATS
Attempts to
contain spill
DISPERSANTS
BREAK UP OIL
CONTAINMENT BOOMS

33. Clean-up efforts

34. Oil in Ecuador
• Ecuador 2nd largest
S. America
producer
– 70% of exports
• Drilling in Amazon
rainforest

35. So why do we still burn fossil
fuels for our energy?