1. 15
Nonrenewable Energy

2. Core Case Study: Is the United States Entering a New Oil and Natural Gas Era?
Two most widely used natural resources in the U.S.
Oil consumption is increasing
New extractions from oil shale cause environmental harm
Burning oil and natural gas will continue adding greenhouse gases to the atmosphere

3. 5% Nuclear power 8% Natural gas 28% RENEWABLE Coal 22% Hydropower 3%
Oil 37%
Figure 15-1: Sources of energy used in the United States in Oil, the most widely used resource, is removed from deposits underground and from deep under the ocean floor in some coastal areas (see photo).
NONRENEWABLE 95%
Geothermal, solar, wind
biomass 2%
Fig. 15-1a, p. 374

4. Figure 15-1: Sources of energy used in the United States in 2011
Figure 15-1: Sources of energy used in the United States in Oil, the most widely used resource, is removed from deposits underground and from deep under the ocean floor in some coastal areas (see photo).
Fig. 15-1b, p. 374

5. 15-1 What is Net Energy and Why Is It Important?
Energy resources vary greatly in their net energy yields

6. Net Energy Is the Only Energy That Really Counts
Net energy yield
Total amount of useful, high-quality energy available from a resource minus the energy needed to make the energy available to consumers
Related to:
Energy return on investment (EROI)
Energy obtained per unit of energy used to obtain it

7. Net Energy Is the Only Energy That Really Counts (cont’d.)
First law of thermodynamics (law of conservation of energy):
It takes high-quality energy to get high-quality energy
Pumping oil from ground, refining it, and transporting it
Second law of thermodynamics (High qualitylow quality)
Some high-quality energy is wasted at every step

8. Some Energy Resources Need Help to Compete in the Marketplace
An energy resource with a low or negative net yield cannot compete in open markets with alternatives that have higher net energy yields
Need subsidies from taxpayers
For example: nuclear power
Has a low net energy yield because a great deal of high quality energy is needed
The uranium fuel cycle is costly
Heavily subsidized

9. 15-2 What Are the Advantages and Disadvantages of Oil?
Conventional crude oil is abundant and has a medium net energy yield, but using it causes air and water pollution and releases greenhouse gases to the atmosphere
Unconventional heavy oil from oil shale rock and tar sands exists in potentially large supplies but has a low net energy yield and a higher environmental impact than conventional oil

10. We depend heavily on oil
Oil is the world’s most widely used energy resource.
Used to:
heat our homes
grow most of our food
transport people and goods
make other energy resources available for use
manufacture most of the things we use everyday from plastics to cosmetics to asphalt on roads.

11. We Depend Heavily on Oil
Crude oil (petroleum)
Black, gooey liquid consisting mostly of a mix of different combustible hydrocarbons along with small amounts of sulfur, oxygen, and nitrogen impurities.
Formed from decayed remains of ancient organisms that were crushed beneath layers of rock for millions of years.
Oil companies use huge machines to drill holes and remove rock cores to extract oil.

12. Crude oil cannot be used as it comes out of the ground
Peak production –
After a decade or so, the pressure in the well drops and the oil production declines
Global peak production for all world oil occurs when conventional oil declines faster than new oil field are found
Crude oil cannot be used as it comes out of the ground
Must be refined into:
Petrochemicals

13. Lowest Boiling Point Gases Gasoline Aviation fuel Heating oil
Diesel oil
Naphtha
Figure 15-4: When crude oil is refined, many of its components are removed at various levels of a distillation column, depending on their boiling points. The most volatile components with the lowest boiling points are removed at the top of the column, which can be as tall as a nine-story building. The photo shows an oil refinery in Texas.
Grease and wax
Heated crude oil
Asphalt
Furnace
Highest Boiling Point
Fig. 15-4a, p. 377

14. Figure 15-4: When crude oil is refined, many of its components are removed at various levels of a distillation column, depending on their boiling points. The most volatile components with the lowest boiling points are removed at the top of the column, which can be as tall as a nine-story building. The photo shows an oil refinery in Texas.
Fig. 15-4b, p. 377

15. Are We Running Out of Conventional Oil?
How much oil is there?
Availability determined by:
1.Demand
2.Technology
3. Rate at which we remove the oil
4. Cost of making oil available
5. Market price
Proven oil reserves –
available deposits from which oil can be extracted profitably; not fixed.

16. Are We Running Out of Conventional Oil? (cont’d.)
To avoid running out of oil:
1. Use unconventional heavy oil
Higher environmental cost; production cost
2. Rely on three major options:
1. Live with much higher oil prices
2. Extend oil supplies (for example, improve vehicle efficiency)
3. Use other energy sources

17. Barrels of oil per year (billions)
Projected U. S.
oil consumption
Barrels of oil per year (billions)
Figure 15-5: The amount of conventional light crude oil that might be found in the Arctic National Wildlife Refuge, if developed and extracted over 50 years, is a tiny fraction of the projected U.S. demand for oil.
Arctic refuge oil output over 50 years
Year
Fig. 15-5a, p. 379

18. Figure 15-5: The amount of conventional light crude oil that might be found in the Arctic National Wildlife Refuge, if developed and extracted over 50 years, is a tiny fraction of the projected U.S. demand for oil.
Fig. 15-5b, p. 379

19. Use of Conventional Oil Has Environmental Costs
Land disruption, greenhouse gas emission, air pollution, water pollution, and loss of biodiversity
Burning oil accounts for 43% of global CO2 emissions

20. Trade-Offs Conventional Oil Advantages Disadvantages
Ample supply for several decades
Water pollution from oil spills and leaks
Environmental costs not included in market price
Net energy yield is medium but decreasing
Releases CO2 and other air pollutants when burned
Low land disruption
Figure 15-6: Using conventional light oil as an energy resource has advantages and disadvantages. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Do the advantages of relying on conventional light oil outweigh its disadvantages? Explain.
Efficient distribution system
Vulnerable to international supply interruptions
Fig. 15-6, p. 380

21. Case Study: Oil Production and Consumption in the United States
The U.S.:
Produces 9% of the world’s oil and uses 23% of world’s oil
Has about 2% of world’s proven oil reserves
Imports 52% of its oil
Should we look for more oil reserves?
Extremely difficult
Expensive and financially risky

22. Heavy Oil From Oil Shale Rock
A potential supply of heavy oil is shale oil
Oil shale rock contains kerogen that can be distilled to produce shale oil
72% of the world’s reserve is in arid areas of western United States
Locked up in rock; requires lots of energy, money, and water
Lots of pollution, in air and water
Low net energy yield

23. Figure 15-7: Heavy shale oil (right) can be extracted from oil shale rock (left).
Fig. 15-7, p. 381

24. Heavy Oil from Tar Sands
Another soil of heavy oil is tar sands, or oil sands, which are a mixture of clay, sand, water, and contains bitumen ( a thick, sticky, tarlike heavy oil)
Extensive deposits in Canada and Venezuela
Oil sands have more oil than in Saudi Arabia
Problems with extraction
Serious environmental impacts
Low net energy yield

25. Figure 15-8: This gooey tar, or bitumen, with the consistency of peanut butter, was extracted from tar sands in Alberta, Canada, to be converted to heavy synthetic oil.
Fig. 15-8, p. 381

26. Heavy Oils from Oil Shale and Tar Sand
Trade-Offs
Heavy Oils from Oil Shale and Tar Sand
Advantages
Disadvantages
Large potential supplies
Low net energy yield
Easily transported within and between countries
Releases CO2 and other air pollutants when produced and burned
Figure 15-10: Using heavy oil from tar sands and from oil shale rock as an energy resource has advantages and disadvantages (Concept 15-2). Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Do the advantages of relying on heavy oil from these sources outweigh the disadvantages? Explain.
Efficient distribution system in place
Severe land disruption and high water use
Fig , p. 382

27. 15-3 What Are the Advantages and Disadvantages of Using Natural Gas?
Conventional natural gas:
Is more plentiful than oil
Has a medium net energy yield and a fairly low production cost
Is a clean-burning fuel
However, producing it has created environmental problems

28. Natural Gas Is a Useful, Clean-Burning, but Not Problem-Free Fossil Fuel
mixture of gases, 50-90% methane CH4
Medium net energy yield
Widely used for cooking, heating space and water, industrialized purposes
Provides 28% of energy consumed in US
Burns cleaner than oil and much cleaner than coal.

29. Conventional natural gas
Often found in deposits above conventional oil, as well as in shale rock.
When a natural gas deposit is tapped, propane and butane gases can be liquefied under high pressure and removed as:
1. Liquefied petroleum gas (LPG)
Stored in tanks

30. 2. Liquefied natural gas (LNG)
Way by which to transport across oceans
Low net energy yield

31. Natural Gas Is a Useful, Clean-Burning, but Not Problem-Free Fossil Fuel (cont’d.)
The U.S. produces natural gas conventionally and from shale rock
US does not have to rely on natural gas imports
Increasing environmental problems with shale rock extraction

32. 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
Figure 15-11: Using conventional natural gas as an energy resource has advantages and disadvantages. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Do you think that the advantages of using conventional natural gas outweigh the disadvantages? Explain.
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

33. Case Study: Natural Gas Production and Fracking in the U.S.
Drilling wells; using huge amounts of water, sand, and chemicals; dealing with toxic wastewater; transporting the natural gas
Drinking water contaminated with natural gas can catch fire
Fracking has several harmful environmental effects

34. Figure 15-12: Natural gas fizzing from this faucet in a Pennsylvania home can be lit like a natural gas stove burner. This began happening after an energy company drilled a fracking well in the area, but the company denies responsibility. The home owners have to keep their windows open year-round to keep the lethal and explosive gas from building up in the house.
Fig , p. 384

35. Figure 15-13: Solutions: Reforms such as these, recommended by several energy analysts, could reduce the harmful impact of shale gas production. Questions: Which three of these steps do you think are the most important ones to take? Explain.
Fig , p. 385

36. Unconventional Natural Gas
1.Coal bed methane gas
Found in coal beds near the earth’s surface; in shale beds
High environmental impacts of extraction
2. Methane hydrate
Trapped in icy water; in permafrost environments; on ocean floor
Costs of extraction is currently too high

37. 15-4 What Are the Advantages and Disadvantages of Coal?
Conventional coal is plentiful and has a high net energy yield at low costs, but using it results in a very high environmental impact
We can produce gaseous and liquid fuels from coal, but they have lower net energy yields and using them would result in higher environmental impacts than those of conventional coal

38. Coal Is a Plentiful but Dirty Fuel
Solid fossil fuel formed from the remains of land plants that were buried million years ago and exposed to intense heat and pressure over millions of years
Burned in power plants
Generates 42% of the world’s electricity
Abundant fossil fuel– world’s largest coal reserves United States, Russia, China

39. Coal Is a Plentiful but Dirty Fuel (cont’d.)
Environmental costs of burning coal
Dirtiest of all fossil fuels
Severe air pollution
Sulfur released as SO2
Large amount of soot
CO2
Trace amounts of mercury and radioactive materials

40. 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)
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
Figure 15-14: Over millions of years, several different types of coal have formed. Peat is a soil material made of moist, partially decomposed organic matter, similar to coal; it is not classified as a coal, although it is used as a fuel. These different major types of coal vary in the amounts of heat, carbon dioxide, and sulfur dioxide released per unit of mass when they are burned.
Fig , p. 386

41. Cooling tower transfers waste heat to atmosphere Coal bunker Turbine
Generator
Cooling loop
Stack
Pulverizing mill
Condenser
Filter
Figure 15-15: This power plant burns pulverized coal to boil water and produce steam that spins a turbine to produce electricity. The largest coal-burning power plant in the United States, located in Indiana, burns three 100-car trainloads of coal per day. Question: Does the electricity that you use come from a coal-burning power plant?
Boiler
Ash disposal
Fig a, p. 387

42. Figure 15-15: This power plant burns pulverized coal to boil water and produce steam that spins a turbine to produce electricity. The largest coal-burning power plant in the United States, located in Indiana, burns three 100-car trainloads of coal per day. Question: Does the electricity that you use come from a coal-burning power plant?
Fig b, p. 387

43. The Clean Coal Campaign
To keep their profits, coal companies and energy companies has fought:
Classifying carbon dioxide as a pollutant
Classifying coal ash as hazardous waste
Air pollution standards for emissions
The 2008 clean coal campaign
Note: there is no such thing as clean coal

44. Coal-fired electricity 286%
Synthetic oil and gas produced from coal
150%
Coal
100%
Tar sand
92%
Oil
86%
Natural gas
58%
Figure 15-17: CO2 emissions, expressed as percentages of emissions released by burning coal directly, vary with different energy resources. Question: Which of these produces more CO2 emissions per kilogram: burning coal to heat a house, or heating with electricity generated by coal?
Nuclear power fuel cycle
17%
Geothermal
10%
Fig , p. 388

45. Trade-Offs Coal Advantages Disadvantages
Severe land disturbance and water pollution
Ample supplies in many countries
Fine particle and toxic mercury emissions threaten human health
Medium to high net energy yield
Figure 15-20: Using coal as an energy resource has advantages and disadvantages. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Do you think that the advantages of using coal as an energy resource outweigh its disadvantages? Explain.
Low cost when environmental costs are not included
Emits large amounts of CO2 and other air pollutants when produced and burned
Fig , p. 389

46. We Can Convert Coal into Gaseous and Liquid Fuels
Conversion of solid coal to:
Synthetic natural gas (SNG) by coal gasification to remove sulfur and impurities from coal
Methanol or synthetic gasoline by coal liquefaction, synfuels, cleaner version of coal
Are there benefits to using these synthetic fuels?
Eh…—requires mining of 50% more coal; produces and burning synfuels leads to more CO2 in atmosphere; lots of water; lots energy; high cost for low yield

47. Trade-Offs Synthetic Fuels Advantages Disadvantages
Large potential supply in many countries
Low to medium net energy yield
Requires mining 50% more coal with increased land disturbance, water pollution and water use
Vehicle fuel
Figure 15-21: The use of synthetic natural gas (SNG) and liquid synfuels produced from coal as energy resources has advantages and disadvantages (Concept 15-2). Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Do you think that the advantages of using synfuels produced from coal as an energy source outweigh the disadvantages? Explain.
Lower air pollution than coal
Higher CO2 emissions than coal
Fig , p. 389

48. 15-5 What Are the Advantages and Disadvantages of Using Nuclear Power?
Nuclear power has a low environmental impact and a very low accident risk, but its use has been limited by:
A low net energy yield, high costs, fear of accidents, and long-lived radioactive wastes
Its role in spreading nuclear weapons technology

49. Nuclear Power Plant Nuclear Power Plant
A highly complex and costly system designed to perform a relatively simple task: to boil water and produce steam that spins a turbine and generates electricity.

50. How Does a Nuclear Fission Reactor Work?
Uses complex and costly controlled nuclear fission reaction
Takes place in a reactor
Light-water reactors; Very inefficient
Fueled by uranium ore and packed as pellets in fuel rods and fuel assemblies in the core of a reactor
Control rods absorb neutrons generated in fission, regulating the rate of fission and amount o power produced

51. How Does a Nuclear Fission Reactor Work? (cont’d.)
Takes place in a reactor (continued)
Water is the usual coolant; keeps components from melting and releasing radioactivity into the environment.
Containment shell around the reactor core to ensure radioactive materials do not escape into the environment.
Water-filled pools or dry casks for storage of radioactive wastes and spent fuel rod assemblies 51

52. Pump Pump Pump Pump Water source (river, lake, ocean)
Small amounts of radioactive gases
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
Figure 15-22: This water-cooled nuclear power plant, with a pressurized water reactor, produces intense heat that is used to convert water to steam, which spins a turbine that generates electricity. Question: How does this plant differ from the coal-burning plant in Figure 15-15?
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

53. Figure 15-22: This water-cooled nuclear power plant, with a pressurized water reactor, produces intense heat that is used to convert water to steam, which spins a turbine that generates electricity. Question: How does this plant differ from the coal-burning plant in Figure 15-15?
Fig b, p. 390

54. What Is the Nuclear Fuel Cycle?
1. Mine the uranium
2. Process and enrich the uranium to make the fuel
3. Use it in the reactor
4. Safely store the radioactive waste
5. Decommission the reactor

55. (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
Figure 15-23: Science. Using nuclear power to produce electricity involves a sequence of steps and technologies that together are called the nuclear fuel cycle. Question: Do you think the market price of nuclear-generated electricity should include all the costs of the nuclear fuel cycle, in keeping with the full-cost pricing principle of sustainability? (See Figure 1-5, p. 9 or back cover.) Explain.
Geologic disposal of moderate
and high-level radioactive wastes
Mining uranium
ore (U3O8)
Open fuel cycle today
Recycling of nuclear fuel
Fig , p. 392

56. Trade-Offs Conventional Nuclear Fuel Cycle Advantages Disadvantages
Low environmental impact (without accidents)
Low net energy yield
High overall cost
Emits 1/6 as
much CO2 as coal
Produces long-lived, harmful radioactive wastes
Figure 15-24: Using the nuclear power fuel cycle (Figure 15-23) to produce electricity has advantages and disadvantages. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Do you think that the advantages of using nuclear power outweigh its disadvantages? Explain.
Low risk of accidents in modern plants
Promotes spread of
nuclear weapons
Fig , p. 392

57. Storing Radioactive Spent-Fuel Rods Presents Risks
Uranium fuel in a nuclear reactor lasts for 3- 4 years; reactors are shut down for refueling
Extremely hot spent-fuel rods must be replaced, and are stored and cooled in water-filled pools
Placed in dry casks made of heat-resistant metal alloys and concrete filled with Helium
Must be stored for thousands of years
Vulnerable to terrorist attack

58. Figure 15-25: After 3 or 4 years in a reactor, spent-fuel rods are removed and stored in a deep pool of water contained in a steel-lined concrete basin (left) for cooling. After about 5 years of cooling, the fuel rods can be stored upright on concrete pads (right) in sealed dry-storage casks made of heat-resistant metal alloys and thick concrete. Questions: Would you be willing to live within a block or two of these casks or have them transported through the area where you live in the event that they were transferred to a long-term storage site? Explain. What are the alternatives?
Fig , p. 393

59. Dealing with Radioactive Nuclear Wastes Is a Difficult Problem
High-level radioactive wastes
Must be stored safely for 10,000–240,000 years; too expensive to reprocess
Where can it be stored?
Deep burial: safest and cheapest option
There is still no facility
Shooting it into space is too dangerous

60. Dealing with Radioactive Nuclear Wastes Is a Difficult Problem (cont’d
Plans in the U.S. to build a repository for high-level radioactive wastes in the Yucca Mountain desert region (Nevada)
Many problems including:
Cost of $96 billion
Rock fractures
Earthquake zone
Decrease national security

61. Dealing with Radioactive Nuclear Wastes Is a Difficult Problem (cont’d
Dealing with old nuclear power plants:
Nuclear power plants reach the end of useful life after years and must close
Decommission or retire the power plant
Dismantle the plant and safely store the radioactive materials
Enclose the plant behind a physical barrier with full-time security until a storage facility has been built
Enclose the plant in a tomb
Monitor this for thousands of years

62. Can Nuclear Power Help Reduce Climate Change?
Nuclear power plants – no CO2 emission
However, building plants as well as the nuclear fuel cycle – emits CO2
Need high rate of building new plants, and a storage facility for radioactive wastes

63. Experts Disagree about the Future of Nuclear Power
Proponents of nuclear power:
Fund more research and development on safer and lest costly type of reactions
Pilot-plant testing of potentially cheaper and safer reactors
Opponents of nuclear power:
Very expensive; does not save on oil
Questions of safety
Fund rapid development of energy efficient and renewable energy resources

64. Experts Disagree about the Future of Nuclear Power (cont’d.)
New technologies
Advanced Light Water Reactors (ALWRs)
Safer
Thorium based reactors in place of uranium
Less costly and safer

65. Figure 15-26: Some critics of nuclear power say that any new generation of nuclear power plants should meet all of these five criteria. Question: Do you agree or disagree with these critics? Explain.
Fig , p. 395

66. Case Study: The 2011 Nuclear Power Plant Accident in Japan
Triggered by a major offshore earthquake and resulting tsunami
Four key human-related factors:
No worst-case scenarios
Seawalls too short
Design flaws
Relationship between plant owners and government

67. Figure 15-27: An explosion in one of the reactors in the Fukushima Daiichi nuclear power plant severely damaged the reactor.
Fig , p. 396

68. Is Nuclear Fusion the Answer?
Two isotopes (hydrogen) fused together at extremely high temperatures to form a heavier nucleus; Releases energy in the process
Scientists think it could form a limitless source of energy
No risk of a meltdown or release of large amounts of radioactive material;little risk of nuclear weapons.
Could also destroy toxic wastes and supply electricity to desalinate water!

69. Is Nuclear Fusion the Answer?
Technology is very difficult to develop; 50 years of research and we’re still in the laboratory stage.

70. Three Big Ideas
A key factor to consider in evaluating the long-term usefulness of any energy resource is its net energy yield
Conventional oil, natural gas, and coal:
Plentiful and have moderate to high net energy yields
Use of these fossil fuels, especially coal, has a high environmental impact

71. Three Big Ideas (cont’d.)
The nuclear power fuel cycle has a low environmental impact and a very low accident risk, but limited use because of:
High costs
A low net energy yield
Long-lived radioactive wastes
Its role in spreading nuclear weapons technology

72. Tying It All Together: A New U. S
Tying It All Together: A New U.S. Oil and Natural Gas Era and Sustainability
Conventional fossil fuels have high net energy yields
We cannot recycle energy
Recycling materials can help reduce energy needs
Relying on a diversity of energy resources
Will reduce environmental impacts