MILLER/SPOOLMAN, SUSTAINING THE ENVIRONMENT, 12E
CHAPTER SUMMARY
CHAPTER 9
9-1 What major sources of energy do we use?
The sun provides an essentially inexhaustible supply of solar capital, providing nearly all the energy that heats the
earth and our buildings. CONCEPT 9-1A About three-quarters of the world's commercial energy comes from
nonrenewable fossil fuels, and the rest comes from nonrenewable nuclear fuel and renewable sources. CONCEPT
9-1B Net energy is the amount of high-quality usable energy available from a resource after the amount of energy
needed to make it available is subtracted.
1. With what criteria should energy resources be evaluated?
2. What is the significance of the concept of net energy?
9-2 What are the advantages and disadvantages of oil?
The United States uses 24% of global oil production, while only having 2.4% of global oil reserves. The U.S.
economy and many others in the developed world depend on inexpensive oil supplies. CONCEPT 9-2A
Conventional oil is currently abundant, has a high net energy yield, and is relatively inexpensive, but using it causes
air and water pollution and releases greenhouse gases into the atmosphere. CONCEPT 9-2B Heavy oils from oil
sand and oil shale exist in potentially large supplies but have low net energy yields and higher environmental
impacts than conventional oil has.
3. What are several products we obtain from refining crude oil?
4. Why is petroleum useful as an energy resource? What are the disadvantages?
5. Distinguish between shale oil and tar sands. Despite their large worldwide reserves, these are not good
choices for supplying the world's oil. Why?
9-3 What are the advantages and disadvantages of natural gas?
Conventional natural gas is found above most reservoirs of crude oil. Natural gas is a versatile fuel, yet it has a high
transportation costs. CONCEPT 9-3 Conventional natural gas is more plentiful than oil, has a high net energy yield
and a fairly low cost, and has the lowest environmental impact of all fossil fuels.
6. Distinguish between natural gas, liquefied petroleum gas, and liquefied natural gas.
7. List the advantages and disadvantages of using natural gas as an energy source.
9-4 What are the advantages and disadvantages of coal?
Coal is a solid fossil fuel that is burned in power plants to provide about 40% of the world's electricity. Burning coal
releases large amounts of soot, carbon dioxide, and trace amounts of toxic mercury and radioactive materials.
CONCEPT 9-4 Conventional coal is plentiful and has high net energy yield and low cost, but it has a very high
environmental impact: synthetic fuels produced from coal have lower net energy yields and higher environmental
impacts than conventional coal has.
8. Evaluate the usefulness of coal as an energy source.
9-5 What are the advantages and disadvantages of nuclear energy?
To evaluate nuclear energy, we must consider safety, economic feasibility, and environmental feasibility of the
entire nuclear fuel cycle, from mining fuel to dealing with the waste. CONCEPT 9-5 Nuclear power has a low
environmental impact and a low accident risk, but high costs, radioactive wastes, vulnerability to sabotage, and the
potential for spreading nuclear weapons technology have limited its use.
9. What are the advantages of nuclear power?
10. What are the challenges associated with using nuclear power? Be sure to consider all parts of the nuclear
fuel cycle.
11. What are important considerations in predicting the future of nuclear power?