1. Chapter 11 Fossil Fuels

2. Overview Energy Sources and Consumption How Fossil Fuels are Formed
Coal
Coal Reserves and Mining
Environmental Impacts
Oil and Natural Gas
Exploration for Reserves of Oil and Natural Gas
Arctic National Wildlife Refuge
Synfuels
US Energy Strategy

3. Energy Sources and Consumption
Energy sources used to be local
Now they are worldwide
Fossil fuels (55.5% imported)
Nuclear energy
Electricity
Energy consumption is different between developing and developed nations
20% of world’s population use 60% of the world’s energy sources (developed uses 8x’s more than developing)

4. Per capita energy consumption of selected developed and developing countries

5. Energy consumption in the US
Industries (production) use the most
Heating, cooling, and illuminating building is 1/3

6. Fossil Fuels Combustible deposits in the Earth’s crust
Composed of the remnants (fossils) of prehistoric organisms that existed millions of years ago
Includes coal, oil (petroleum) and natural gas
Non-renewable resource
Fossil fuels are created too slowly to replace the reserves we use
We will have to transition to other sustainable fuels in the future

7. How Are Fossil Fuels Formed?
300 million years ago
Climate was mild
Vast swamps covered much of the land
Dead plant material decayed slowly in the swamp environment
Plants include giant ferns, horsetails, and club mosses

8. How Are Fossil Fuels Formed
Over time, layers of sediment accumulated over the dead plant material
Coal
Heat, pressure and time turned the plant material into carbon-rich rock (coal)
Oil
Sediment deposited over microscopic plants
Heat pressure and time turned them into hydrocarbons (oil)
Natural Gas
Formed the same way as oil, but at temperatures higher than 100 °C

9. Coal Occurs in different grades Lignite Subbitumimous Bituminous
Based on variations in heat and pressure during burial
Lignite
Subbitumimous
Bituminous
Anthracite
Most, if not all, coal deposits have been identified
Primarily in northern hemisphere

10. Coal Types and Quality
Lignite –poor quality, dark brown, 30% carbon, $11.41 (per 2000 lbs to mine), heat value 6000 btu/lb
Subbituminous – Poor quality but better, dull black, 40% carbon, $7.12, heat value 9000 btu/lb
Bituminous – also called soft coal, high sulfur , 50-70% carbon, $24.15 to mine, btu/lb
Antracite- black, high quality, low sulfur,90% carbon, $40.90 to mine, 14,000 btu/lb (fig 10.1)

11. Coal US has 25% of world’s coal supplies
Known coal deposits could last 200 years
At present rate of consumption

12. 2 Types of Coal Mining Surface mining (right) Subsurface mining
Chosen if coal is within 30m of surface
mineral and energy resources are extracted near Earth’s surface by first removing the soil, subsoil, and overlying rock strata
Subsurface mining
Extraction of mineral and energy resources from deep underground deposits
Surface mine near Wyoming

13. Environmental Impacts of Mining Coal
Surface Mining Control and Reclamation Act (1977)
Requires filling (reclaiming) of surface mines after mining
Expensive!
Reduces Acid Mine Drainage
Requires permits and inspections of active coal mining sights
Prohibits coal mining in sensitive areas
Mountaintop Removal
Fills valleys and streams with debris
Most land destructive tecnique

14. Environmental Impacts of Burning Coal
Releases large quantities of CO2 into atmosphere
Greenhouse gas
Releases other pollutants into atmosphere
Mercury
Sulfur oxides
Nitrogen oxides
Can cause acid precipitation
Dead trees enveloped in acid fog on Mt. Mitchell, North Carolina

15. Making Coal Cleaner Scrubbers Fluidized Bed Combustion (below)
Coal and limestone suspended
Coal burns and limestone neutralizes most of sulfur dioxide
Heat converts water to steam
This powers industrial processes

16. Oil and Natural Gas Oil and gas provide 60% of world’s energy
They provide 63% of US’s energy, 23% provided by coal

17. Petroleum Refining
Numerous hydrocarbons present in crude oil (petroleum) are separated
Based on boiling point
Natural gas contains far fewer hydrocarbons than crude oil
Methane, ethane, propane and butane

18. Oil and Natural Gas Exploration
Oil and natural gas migrate upwards until they hit impermeable rock
Usually located in structural traps

19. Oil Reserves Uneven distribution globally
More than half is located in the Middle East which includes Iran, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, Syria, Yemen, and the United Arab Emirates

20. Natural Gas Reserves Uneven distribution globally
More than half is located in Russia and Iran (app. 48% of worlds deposits)

21. How long will Supplies Last?
Difficult to determine and estimates vary
Depends on:
How many more deposits will be located
What technology might be available to extract deeper resources
Changes in global consumption rates
Experts indicate there may be shortages in 21st century
Long lines at gas station as a result of the OPEC oil embargo in 1973

22. Environmental Impacts of Oil and Natural Gas
Combustion
Increase carbon dioxide and pollutant emissions (nitrogen oxides/photochemical smog)
Natural gas is far cleaner burning than oil
Production
Disturbance to land and habitat
Transport
Spills- especially in aquatic systems
Ex: Alaskan Oil Spill (1989)

23. 1989 Alaskan Oil Spill
Water currents caused the oil to spread hundreds of miles

24. 1989 Alaskan Oil Spill
Exxon Valdez hit a reef and spilled 260,000 barrels of crude oil into sound
Largest oil spill in US history
Led to Oil Pollution Act of 1990
Worker attempting to cleanup rocky shoreline of Eleanor Island

25. Case in Point - Arctic National Wildlife Refuge

26. Synfuel and Other Fossil Fuel Resources
A liquid or gaseous fuel that is synthesized from coal and other naturally occurring sources
Used in place of oil or natural gas
Include:
Tar sands
Oil shales
Gas hydrates
Liquefied coal
Coal gas (right)

27. US Energy Strategy
Objective 1: Increase Energy Efficiency and Conservation
Requires many unpopular decisions
Examples
Decrease speed limit to conserve fuel
Eliminate government subsidies
Objective 2: Secure Future Fossil Fuel Energy Supplies
2 oppositions: environmental and economic

28. US Energy Strategy Objective 3: Develop Alternative Energy Sources
Who should pay for this? Gas taxes?
Objective 4: Meet the First Three Objectives Without Further Damage to the Environment

29. National Energy Policy (2005)