1. Nonrenewable Energy
Chapter 15

2. Energy Resources and Fossil Fuels

3. Fossil Fuels
Most of the energy we use comes from a group of natural resources called fossil fuels.
Fossil fuels – are the remains of ancient organisms that changed into coal, oil, or natural gas.

4. Fuels for Different Uses
Fuels are used for four main purposes:
Transportation
Manufacturing
Heating and cooling buildings
Generating electricity to run machines and appliances.

5. Types of Nonrenewable Energy
Coal, oil, natural gas, and uranium (used for nuclear power) are all nonrenewable energy resources.

6. Commercial Energy Use by Source for the World and the United States

7. Electricity
The energy in fuels is often converted into electrical energy in order to power machines, because electricity is more convenient to use.

8. How is electricity generated?
Electric generator – a machine that converts mechanical energy, or motion, into electrical energy.
Most commercial electric generators convert the movement of a turbine into electrical energy
Turbine - a wheel that changes the force of a moving gas or a liquid into energy that can do work.

9. Cooling tower transfers waste heat to atmosphere Coal bunker Turbine
Generator
Cooling loop
Stack
Pulverizing mill
Condenser
Filter
Boiler
Ash disposal
Fig a, p. 387

10. Energy Use
Everything from the food you eat to the clothes you wear requires energy to produce.

11. Energy Use
People in developed societies use much more energy than people in developing countries do.

12. Energy Use in the US
The United States uses more energy per person than any other country in the world except Canada and the United Arab Emirates.

13. Fossil Fuels
Nonrenewable energy
Coal
Oil
Natural gas

14. Advantages and Disadvantages of Oil
Oil that is pumped from the ground is also known as crude oil, or Petroleum
Petroleum product – anything that is made from crude oil, such as fuels, chemicals, and plastics

15. Lowest Boiling Point Gases Gasoline Aviation fuel Heating oil
Diesel oil
Naphtha
Grease and wax
Heated crude oil
Asphalt
Furnace
Highest Boiling Point
Fig. 15-4a, p. 377

16. Locating Oil Deposits
Oil is found in and around major geologic features that tend to trap oil as it moves in the Earth’s crust.
Exploration wells are drilled to determine the volume and availability of the oil deposit
If enough oil for profit, will drill
Seismic Imaging

17. Oil Formation
Oceanic microscopic plants/animals die, sink to bottom, form layers of sediment
Buried deeper, increased heat/pressure
Amount of heat determines oil or natural gas
High heat – lighter oil
Even higher heat – natural gas
Will migrate through pores until it gathers under impermeable layer

20. Predicting Oil Production
Oil reserves - are oil deposits that can be extracted profitably at current prices using current technology.
Oil deposits are yet to be discovered or to become commercial.

21. The Environmental Effects of Using Oil
When petroleum fuels are burned, they release pollutants.
These pollutants contribute to the formation of smog and cause health problems.
Carbon dioxide emissions contribute to climate change
Oil spills harm ecosystems

22. OPEC OPEC – Organization of Petroleum Exporting Countries 13 countries
>60% world’s crude oil reserves
Produce 45% of the world’s oil

23. Case Study: ANWR Arctic National Wildlife Refuge (Alaska)

24. Oil Sands and Oil Shales
Oil sand – a mixture of clay, sand, water, and bitumen (organic material)
Canada has 75%
Releases a lot of CO2
Produces a lot of toxic sludge

25. Oil Sands and Oil Shales
Oil shales contain kerogen
After distillation: shale oil
72% of the world’s reserve is in arid areas of western United States
Locked up in rock
Water needed for extraction and processing
Low net energy yield

26. Natural Gas Natural gas contains 50-90% methane (CH4)
Supplies about 21 percent of the world’s nonrenewable energy
Burning natural gas produces fewer pollutants than other fossil fuels
Considered “cleaner”

27. Conventional Natural Gas
Trade-Offs
Conventional Natural Gas
Advantages
Disadvantages
Ample supplies
Low net energy yield for LNG
Versatile fuel
Production and delivery may emit more CO2 and CH4 per unit of energy produced than coal
Medium net energy yield
Fracking uses and pollutes large volumes of water
Emits less CO2 and other air pollutants than other fossil fuels when burned
Potential groundwater pollution from fracking
Fig , p. 383

28. Coal Coal: solid fossil fuel
Burned in 2100 power plants, generates 40% of the world’s electricity
Inefficient
Three largest coal-burning countries
China
United States
Canada

29. Coal Formation

30. Coal Most of the world’s fossil-fuel reserves are made up of coal.
Asia and North America are particularly rich in coal deposits.
Two major advantages of coal
it is relatively inexpensive
it needs little refining after it has been mined.

31. Coal

32. Bituminous (soft coal) Anthracite (hard coal)
Increasing heat and carbon content
Increasing moisture content
Peat
(not a coal)
Lignite
(brown coal)
Bituminous (soft coal)
Anthracite (hard coal)
High grade coal – less pollution
Low grade coal – more pollution
Burning low grade coal that has a lot of sulfur can lead to acid rain.
Heat
Heat
Heat
Pressure
Pressure
Pressure
Partially decayed plant matter in swamps and bogs; low heat content
Low heat content; low sulfur content; limited supplies in most areas
Extensively used as a fuel because of its high heat content and large supplies; normally has a high sulfur content
Highly desirable fuel because of its high heat content and low sulfur content; supplies are limited in most areas

33. Cooling tower transfers waste heat to atmosphere Coal bunker Turbine
Generator
Cooling loop
Stack
Pulverizing mill
Condenser
Filter
Boiler
Ash disposal
Fig a, p. 387

34. Coal Mining and the Environment
Environmental costs of burning coal
Severe air pollution
Sulfur released as SO2
Large amount of soot
CO2
Trace amounts of Hg and radioactive materials
Is there really a “clean coal”?

35. Fossil Fuels and the Future
Today, fossil fuels supply about 90 percent of the energy used in developed countries.
As the demand for energy resources increases, the cost of fossil fuels will likely increase enough to make other energy sources more attractive.

36. Self Quiz What are fossil fuels? How do fossil fuels form?
What are some environmental problems associated with different fossil fuels?
When might renewable energy become more common than fossil fuels?

37. Coal, Oil, and Natural Gas Deposits

39. Hydraulic Fracturing AKA Hydrofracking or Fracking
Method of extracting underground natural gas
Very controversial due to concerns over groundwater pollution
Wastewater associated with shale gas extraction can contain high levels of dissolved solids, fracturing fluid additives, metals, and naturally occurring radioactive materials.

42. Energy Production by Source

43. Nuclear Energy

44. Case Study: Three Mile Island, PA

45. Case Study: Worst Commercial Nuclear Power Plant Accident in the U.S.
Three Mile Island
March 29, 1979
Near Harrisburg, PA, U.S.
Nuclear reactor lost its coolant
Led to a partial uncovering and melting of the radioactive core
Unknown amounts of radioactivity escaped
People fled the area
Increased public concerns for safety
Led to improved safety regulations in the U.S.

46. Case Study: Three Mile Island, PA
The Three Mile Island Unit 2 (TMI-2) reactor, near Middletown, Pa., partially melted down on March 28, This was the most serious accident in U.S. commercial nuclear power plant operating history, although its small radioactive releases had no detectable health effects on plant workers or the public. Its aftermath brought about sweeping changes involving emergency response planning, reactor operator training, human factors engineering, radiation protection, and many other areas of nuclear power plant operations. It also caused the NRC to tighten and heighten its regulatory oversight. All of these changes significantly enhanced U.S. reactor safety.

47. Case Study: Three Mile Island

48. Fission: Splitting Atoms
Nuclear energy- the energy within the nucleus of an atom
Nuclear power plants get their power from nuclear energy
Nuclear fission – splitting the nuclei of atoms
Fission releases a tremendous amount of energy

50. How Nuclear Energy Works
Fueled by uranium ore and packed as pellets in fuel rods and fuel assemblies
Water is the usual coolant
Containment shell around the core for protection
Water-filled pools or dry casks for storage of radioactive spent fuel rod assemblies

51. How Nuclear Energy Works
Small amounts of radioactive gases
How Nuclear Energy Works
Uranium fuel input (reactor core)
Control rods
Containment shell
Waste heat
Heat exchanger
Steam
Turbine
Generator
Hot coolant
Useful electrical energy
about 25%
Hot water output
Pump
Pump
Coolant
Pump
Pump
Waste heat
Cool water input
Moderator
Shielding
Pressure vessel
Coolant passage
Water
Condenser
Periodic removal and storage of radioactive wastes and spent
fuel assemblies
Periodic removal and storage
of radioactive
liquid wastes
Water source
(river, lake, ocean)
Fig a, p. 390

52. (conversion of enriched UF6 to UO2 and fabrication of fuel assemblies)
Decommissioning
of reactor
Fuel assemblies
Reactor
Enrichment
of UF6
Fuel fabrication
(conversion of enriched UF6 to UO2 and fabrication of fuel assemblies)
Temporary storage
of spent fuel assemblies underwater or in dry casks
Conversion
of U3O8
to UF6
Uranium-235 as UF6 Plutonium-239 as PuO2
Spent fuel reprocessing
Low-level radiation with long half-life
Geologic disposal of moderate
and high-level radioactive wastes
Mining uranium
ore (U3O8)
Open fuel cycle today
Recycling of nuclear fuel
Fig , p. 392

54. Advantages of Nuclear Energy
Nuclear energy does not produce air polluting gases
Capable of generating a lot of energy
When operated properly, less radioactivity than coal fired power plants

55. Disadvantages of Nuclear Energy
Storage of waste
Safety concerns
Low net yield of energy of the nuclear fuel cycle
Slowest growing energy source

56. Nuclear Waste Storage Concerns
The difficulty of finding a safe place to store nuclear wastes is one of the greatest disadvantages of nuclear power.
Storage sites for nuclear wastes must be located in areas that are geologically stable for tens of thousands of years.

57. Case Study: Worst Nuclear Power Plant Accident in the World
Chernobyl
April 26, 1986
In Chernobyl, Ukraine
Series of explosions caused the roof of a reactor building to blow off
Partial meltdown and fire for 10 days
Huge radioactive cloud spread over many countries and eventually the world
350,000 people left their homes
Effects on human health, water supply, and agriculture

58. Remains of a Nuclear Reactor at the Chernobyl Nuclear Power Plant

59. Fukushima

60. Fukushima

61. Half Life Practice
The half-life of strontium-90 is 25 years. How much strontium-90 will remain after 100 years if the initial amount is 4.0 g?
Potassium-42 has a half-life of 12.4 hours. How much of an 848 g sample of potassium-42 will be left after 62.0 hours?