1. Nonrenewable Energy Resources
Chapter 12
Nonrenewable Energy Resources

2. Nonrenewable Energy Sources cannot be replenished Fossil fuels
Biological basis
Nuclear fuels
Radioactive basis

3. Commercial and Subsistence Energy
Commercial energy
Produced, bought and sold on a large scale
Coal, oil, natural gas, wood, charcoal, peat, animal waste, wind, hydroelectric
Subsistence energy
Gathered or created by individuals for personal use
wood, charcoal, peat, animal waste, wind, hydro

4. World Energy Use Reported in exajoules In US can be reported as quads
= 1 x 109 gigajoules
1 gigajoule = 1 x 109 joules
In US can be reported as quads
1 x 1015 BTU
In US per capita energy use = 355 GJ

5. US Energy Use
Has shifted from wood to fossil fuels over the past 150 years
Hydroelectric and nuclear power have been developed in the past 75 years
Use changes regionally and seasonally

8. Energy Sources Primary Sources Secondary Sources
Produce usable energy through combustion or other reactions
Sunlight, fire, fossil fuels
Secondary Sources
Obtained from the conversion of a primary source to energy
Electricity

9. Energy Types Depend on what it’s used for
Compact, portable sources are best for transportation
Other types can be good for heat, cooking, or generating electricity

10. Energy Quality
The energy provided by a resource must be compared to the energy required to obtain and use the resource
High quality energy sources require little energy to produce compared to the energy they generate
The inputs required to extract and use an energy resource are called embodied energy

11. Energy Efficiency Can be a good measure of energy quality
Can be measured as EROEI (energy return on energy investment)
Energy produced from a source for the unit of energy expended on its production

15. Transportation
Mostly accomplished by vehicles fueled with petroleum or electricity
Accounts for 30% of the energy use in the US and a large portion of air pollution
Vehicles that use less fuel or carry a large number of passengers are generally more efficient

16. Electricity Is an energy carrier
Movable, can deliver energy to users
40% of energy use in the US is for electricity generation
Only 13% of the energy converted into electricity is available for end users

17. Electricity Generation
Fuel is burned to generate heat
Heat is used to generate steam
Steam turns turbines
Turbines turn generators
Generators generate electricity
Electricity is sent out on wires through an electrical grid

19. Combined Cycle Plants Natural gas is burned
A turbine is turned to generate electricity
Waste heat is used to generate steam
Steam turns a turbine which generates electricity

21. Cogeneration Also called combined heat and power
Steam can be used to heat buildings and turn turbines to generate power
Best used in industries that use steam or generate their own power

22. Electrical Capacity Is the maximum electrical output
Is 500 megawatts (MW) for the average thermal power plant
Must take into account the capacity factor
The amount of time a power plant actually operates
Thermal power plants can be as high as 0.9
Other forms of energy generation can be as low as 0.25

23. Electricity Efficiency
Thermal power plants (coal, nuclear) are about 35% efficient
Combined cycle plants are about 60% efficient
Cogeneration plants are about 90% efficient

24. Fossil Fuels Include coal, oil, and natural gas
Most commonly used primary energy source in the world
Form when organic matter is exposed to high heat and pressure over long periods of time (kerogen)
Form most often in swamps, river deltas, and the ocean floor

25. Coal Forms from compressed plants Lignite
Youngest coal; least amount of energy content
Sub-bituminous and Bituminous
Middle-aged coal; most common type
Also called soft coal
Anthracite
Oldest coal; has the highest energy content
Also called hard coal

27. Coal Is used in 50% of the power plants in the US
Is one of the cheapest fuels
Easier to extract than others
Cheaper to build and operate coal power plants than other types

28. Problems with Coal Storage of ash from burning
If above ground, can be washed or blown away
If buried, can leach pollutants into soil and groundwater
Releases high levels of CO2 and other pollutants when burned
Sulfur
Metals
Mercury
Lead
Arsenic

29. Petroleum
Forms from compressed algae in the spaces of sedimentary rocks
Capped by non-porous rocks
This cap must be drilled through to extract the oil
Called crude oil
Pumped out
Flows out artesian-style

30. Petroleum Refining* Extracts various petroleum products from crude oil
Involves heating crude oil and allowing components to condense out

32. Petroleum Use Major use is for fuel
Gasoline accounts for 50% of petroleum use in the US
Also used to make products from plastics to pharmaceuticals

34. Problems with Petroleum
Releases pollutants
Fewer than coal
Extraction and transport are expensive and can be damaging
Oil spills

36. Natural Gas Also called methane, CH4
Forms as a byproduct from petroleum, or by itself from organic decomposition
Used for electricity, industrial processes, and transportation
Releases less CO2 and fewer pollutants than coal or petroleum

38. Problems with Natural Gas
Methane is a very potent greenhouse gas
Leaks can be worse than CO2
Extraction is harmful to the environment
“Thumper” trucks
Fracking

40. Fracking Short for hydraulic fracturing
Is an extreme form of natural gas extraction
Uses drilling and large quantities of water to create cracks in rock that allow gas to flow out
Can use other chemicals that may harm the environment
Can contaminate groundwater

41. Oil/Tar Sands
Form when oil deposits are not capped with non-porous rock
Bitumen, or tar, is mixed with sand
Makes an oil-filled ooze that is difficult and expensive to extract and refine
Generates 2-3 L of waste water for each L of oil extracted

42. Liquified Coal (CTL, Syngas)
Creates a liquid similar to oil from coal
Burns cleaner than solid coal
Expensive to process
Generates toxic waste

43. The Hubbert Curve and Peak Oil
M. King Hubbert generated a bell curve predicting global maximum oil production
This maximum is called peak oil
Some predictions show we have already reached peak oil
Find new oil sources
Find new oil extraction technologies
Find completely new fuel options

44. Nuclear Energy Uses radioactive fuel Is powered by fission
A neutron hits a large atomic nucleus
Causes the nucleus to split
Releases more neutrons which cause nearby atoms to split
This type of energy does not produce air pollution

45. Nuclear Power Plants
Radioactive fuel rods emit heat, which is absorbed by water
The heated water flows through pipes next to another set of pipes also filled with water
Heat is transferred from one set of pipes to the other
Heat transfer creates steam
Steam turns a turbine
Turbine generates electricity

47. Problems with Nuclear Energy
Processing uranium to make fuel rods generates large amounts of waste
900 kg uranium ore to make 3 kg fuel
Radioactive fuel is a health hazard
Exposure can cause radiation sickness and cancer
Storing radioactive waste safely is difficult and expensive
Controlling nuclear reactions requires constant vigilance

48. Radioactive Waste Must be stored securely and for a LONG time
Still emits radioactivity after it stops producing heat
U-235 has a half-life of 704 million years
High-level waste
Used (“spent”) fuel rods
Low-level waste
Contaminated items, including clothing and tools

51. Controlling Nuclear Reactions
Control rods are used to prevent nuclear reactors from overheating
Made from compounds that absorb radiation
Are inserted in between fuel rods
Too much heat can cause a meltdown of the nuclear fuel

54. Fusion Reactions Power the Sun and other stars
Occur when lighter atoms fuse with heavier atoms
Fusing hydrogen atoms to make helium is the focus of most research
Requires reactors that can withstand heat 10x greater than the sun
Requires only hydrogen for fuel
Generates no radioactive waste