1. ENERGY

2. Topics to be addressed:
Energy sources that fuel our civilization
History of energy use
Patterns of energy production and consumption
Crude oil, coal, natural gas, and nuclear energy
Environmental, political, and social impacts of fossil fuel use

3. Energy sources used today

4. Growth in coal has slowed, but oil and gas are still rising.
Figure 17.5

5. Canadians are the highest per-capita energy users on planet Earth !
CLIMATE
DISTANCES
INDUSTRY
LIFESTYLE/WEALTH

6. Figure 17.3

9. Found in sedimentary rock Remains of prehistoric animals, forests
OIL
Hydrocarbons
Found in sedimentary rock
Remains of prehistoric animals, forests
and sea floor life (FOSSIL FUELS)
Toxic to wildlife (spills)
Climate change
Air pollution and acid rain

10. Canadian production
about 3 million barrels/day
(ie., now red on map!)

11. Fossil fuels
These are fossils in the sense that they are made of remnant decayed material from ancient organisms.
Compressed tissues of plants (and some animals) from 100–500 million years ago store chemical energy from photosynthesis.
This greatly concentrated energy is released when we burn coal, oil, or gas.

12. Fossil Fuels
Anaerobic (without oxygen) decomposition is required for fossil fuel formation.
(Aerobic = decay in presence of oxygen)
Anaerobic environments exist at the bottom of the ocean, in deep lakes, and in swamp sediments.

13. Organic material settles in anaerobic site and is partly decomposed
FOSSIL FUEL FORMATION
Plants and animals die
Organic material settles in anaerobic site and is partly decomposed
Organic material is buried
Heat and pressure alter chemical bonds
Coal, gas, oil formed
Figure 17.6

14. Coal: Compressed under high pressure to form dense carbon structures.
Natural gas: Primarily methane, CH4, is produced:
By bacteria near surface
By heat and pressure deep below ground
Crude oil: Sludgelike mix of hundreds of types of hydrocarbon molecules. Forms at temperatures and pressures found 1.5–3 kilometers below ground.

15. The ANWR National Wildlife Reserve: Contentious US Issue
Alaska’s North Slope
Figure 17.1

16. Distribution of Conventional Fossil Fuel Reserves
Figure 17.8

17. Distribution of Conventional Fossil Fuel Reserves
Saudi Arabia has the most oil.
Russia has the most natural gas.
The U.S. has the most coal.

18. Oil: Drilling Liquid oil exists in pores in rock deep underground.
We must drill into rock and extract oil by using a pressure differential.
The more oil is extracted, the harder it is to extract:

19. Refining Crude Oil
Crude oil from the ground is a messy mix of hundreds of hydrocarbons.
It is put through a refining process to segregate different components.
Small-chain hydrocarbons boil at cooler temperatures in a distillation column, isolating lighter weight oils (e.g., butane).
Long-chain hydrocarbons boil at hot temperatures, isolating heavier oils (e.g., lubricating oils).

20. Refining crude oil

21. Petroleum Products
Refined components of crude oil are used to manufacture many of the material goods we use every day.
Petroleum products include:
Helmet, water bottle, sunglasses, clothing,
sunscreen, gear and chain grease
Figure 17.11

22. Oil Conservation
Although oil is a limited resource, prices have remained low enough that few people feel the need to conserve
Conservation measures taken in the 1970s resulting from fears of oil shortages were mostly abandoned, but recent price increases may cause history to repeat itself
As oil supplies dwindle, conservation will again become popular.

23. He was only a few years off.
Geologist M. King Hubbert predicted U.S. oil production would peak around 1970 and then decline.
He was only a few years off.
Figure 17.15a

24. Depletion of Oil Reserves
World oil reserves are a finite resource as well.
Some observers predict they have peaked.
Figure 17.15b

25. Vehicle Fuel Efficiency
Automobile fuel efficiency rose after the oil shocks of the 1970s, but has stagnated since then.
Figure 17.13

26. Clay, sand, water and bitumen Black oil rich in sulphur
OIL SANDS
Clay, sand, water and bitumen
Black oil rich in sulphur
Oil sands must be heated and treated
with steam to separate bitumen
Energy intensive
Sulphur dioxide emissions
Huge waste disposal ponds
Habitat fragmentation
Greenhouse gas emissions

27. Tar sand
Bitumen
Photos: Syncrude

28. Most CO2 and air pollution per unit energy Sydney tar ponds - the most
COAL
* New technology
may present cleaner
coal burning options
(eg. improved boiler
efficiency)
Most CO2 and
air pollution per
unit energy
Sydney tar ponds
- the most
contaminated site
in Canada
                     
Illustration: Brooks Johnson,
Ontario Clean Air Alliance

29. Several types of coal exist, depending on the amount of heat and pressure that overlying sediments have exerted.
Figure 17.16

30. Coal is mined either underground, in subsurface mining, or from the surface, in strip mining.
Figure 17.17

31. Gaseous hydrocarbon mixture Primarily methane – CH4
Natural Gas
Gaseous hydrocarbon mixture
Primarily methane – CH4
Also C3H8 and C4H10
Now 45% of Canada’s energy production
Much cleaner and more efficient
Problems: potent greenhouse gas,
wildlife disruption, flaring & H2S

32. Natural Gas: History Seeps known for 2,000+ years
Used for street lighting in the 1800s
Became commonly used after WWII once pipeline technology became safer

33. Natural Gas Formation Forms in two ways:
Biogenic gas = formed at shallow depths by anaerobic decomposition of organic matter by bacteria
Thermogenic gas = formed at deep depths as geothermal heating separates hydrocarbons from organic material
(Formed directly OR from crude oil altered by heating. Thus gas deposits often occur with oil deposits.)

34. Gas Extraction
Initially, gas comes out on its own from natural pressure.
Later, it must be pumped out.
Horsehead pump to extract natural gas
Figure 17.18

38. NUCLEAR ENERGY

39. 15% of Canada’s electricity
>50% of Ontario’s electricity

40. Nuclear Power 6.8% of world’s primary energy supply
16.9% of world’s electricity production
Grew 15-fold since 1970
Has stagnated due to safety concerns and economics

41. Nuclear energy Two ways to produce nuclear energy:
Fission: used for power
Fusion: not yet used commercially

42. Nuclear Energy Comes from the radioactive element uranium
The nuclear fuel cycle enriches forms of uranium to make it into usable fuel.
Waste fuel is radioactive and must be specially disposed of.
Figure 17.24

43. Nuclear Energy: Fission
Fission = energy is released by splitting apart uranium nuclei by bombarding them with neutrons.
This is the process used in nuclear reactors and weapons.
Figure 17.25a

44. Nuclear Energy: Fission
Note that several neutrons
are produced from each
reaction with one neutron.
This means the reaction
could be a runaway reaction, or explosion.
In a commercial reactor, the reaction must be controlled.
Metal rods are used to absorb the extra neutrons. Engineers move these control rods to regulate the reaction.
Figure 17.25a

45. Nuclear Reactor
In a reactor, fission boils steam to turn a turbine and generate electricity
Figure 17.26

46. Nuclear Troubles
Although nuclear power is clean, lacking the pollutants of fossil fuels, it has faltered, due to:
• Cost overruns
• Public fears of catastrophic accidents
Three Mile Island, 1979
Chernobyl, 1986
450 nuclear plants remain operating today in the world; 100 have closed.

47. No greenhouse gas emissions/air
pollution (except mining)
Minimal land disturbance
High energy output with minimal
environmental impact
Problems:
Storage of nuclear waste
(DGD in Canadian shield proposed)
Expensive
Public trust / meltdown risk
(older systems)

48. Renewable Energy Sources
Biomass & Biogas: from combustion of organic material
Hydropower: from water flowing through dams
Solar: from the sun’s rays
Wind: from the wind
Geothermal: from heat and heated water beneath the ground
Ocean sources: from the tides and from waves
Hydrogen: fuel and fuel cells that store renewable energy in usable form

49. GLOBAL ENERGY SUPPLY

50. SOURCES OF ELECTRICITY

52. Renewable Sources: Outlook
The outlook for renewable sources is good.
Growth should continue.
But will governments raise subsidies to the level offered to fossil fuels?
Will research and development proceed fast enough?
Will consumers choose alternative energy sources

53. HYDROELECTRIC POWER

54. Turbine generator inside dam

56. Hydro Power 12% of Canada’s energy No air pollution
Downstream irrigation regulation

58. Pros and cons of hydroelectric power
Renewable as long as water is not overdrawn from river system
Clean: no greenhouse gas emissions
CONS
Dams cause numerous disruptive ecological effects to riparian environments
Dams bring a mix of impacts for people

59. WIND ENERGY

60. Wind Power
Takes kinetic energy of wind and converts it to electrical energy
Fastest growing power source today
Technology = wind turbines, machines with turning blades that convert energy of motion into electrical energy by spinning a generator
Windmills have been used for centuries.
First wind turbine for electricity: late 1800s

61. Mean 50m Wind Speed in Canada (m/s)
Source: Canadian Wind Energy Atlas

63. Annual average wind power
Figure 18.12a

64. Wind Power: Wind Turbines
Wind spins the blades, which turn the gearbox, which turns the generator to produce electricity.
Figure 18.9

65. Wind Power: Wind Turbines
Turbines are often located in groups (“wind farms”) at sites with exceptionally good wind conditions.

66. Wind Power Most wind power so far is concentrated in a few nations.
Figure 18.11

67. Wind Power
By surveying with anemometers that measure wind speed, people can determine sites that will be best for wind power production.
From The Science behind the Stories

68. Near zero environmental impact
Potential exists to reverse current
level of impact from other sources
Each turbine powers at least 250
Alberta homes!
It’s windy here!

69. Pros and Cons of Wind Power
Renewable, as long as wind blows
No emissions after equipment made, installed
Can allow local decentralized control over power, and local profit from electricity sales
Costs low after initial investment; costs dropping
CONS
Not everywhere is windy enough
Windy sites can be far from population centers
Blades kill birds, bats
High start-up costs

70. Biomass Organic substances produced by recent photosynthesis
(unlike fossil fuels, products of ancient photosynthesis)
More than 1 billion people
burn fuelwood as their
principal power
source for cooking,
heating, etc.

71. Biomass Wood, agricultural wastes, garbage 15% of world’s energy
6% of Canada’s energy
Mainly in developing nations
Less emission of greenhouse gases if
forest replacement exceeds removal (wood)
Biofuels for cars (ethanol - Brazil)
Problems: land clearing and associated
problems (wood)

72. Pros and Cons of Biomass
Renewable, as long as forests aren’t depleted
Usually inexpensive
Some waste can be used for energy
Capturing methane reduces that greenhouse gas
CONS:
Does not always reduce CO2 emission as much as other renewables
Cutting trees for fuelwood can lead to deforestation
Growing crops for fuel (e.g., corn for ethanol) is highly inefficient

73. Biogas Production from Manure
Electricity Generation
Gas for cooking
Heat
Utilized in Southern Alberta
(eg. Iron Creek Hutterite Colony)
Photos: Rokai Pig Farm,
Kaunas, Lithuania
INLET
OUTLET

74. Difficulties
Temperature optima maintenance
Acidity: pH sensitive anaerobic bacteria
(lime required)
NH3 toxicity (control input rate)
CH4 won’t liquefy – difficult to store
(must use or burn)

75. Geothermal Energy
                                                                                                                                                              

76. Geothermal Energy
Radioactive decay of elements deep in Earth’s core creates heat that rises toward the surface.
This heats magma of volcanoes, and also underground water.
Sometimes water spurts through to the surface in geysers.
Geothermal power plants use the energy of naturally heated water to generate electricity.

77. Geothermal Energy
Underground heat warms water, and steam turns turbines and generators.
Condensed steam is reinjected into the aquifer to keep up pressure.
Figure 18.13a

78. Geothermal Energy
Iceland uses geothermal energy to heat water for 86% of its homes.
Heat pumps using surface heat can also be very efficient.
Geothermal plant in Iceland
Figure 18.13b

79. Pros and Cons of Geothermal Power
Renewable, as long as water is heated naturally
Much lower greenhouse gas emissions than fossil fuels
Can be inexpensive in areas where geothermal heating naturally occurs
CONS
Heated water may give out after a while—hotspot moves or aquifer pressure drops
Salts in water can corrode equipment, shorten lifespan
Limited to geographic areas where geothermal heating naturally occurs

80. Ocean Energy Sources Three sources from oceans:
Tidal power: The twice-daily flow of tides (rising and falling of seas due to the moon’s gravitational pull) creates energy of motion that can be converted to electricity.
Wave power: Motion of waves at ocean shores creates energy of motion that can be converted to electricity.

81. Tidal Energy
The LaRance power station in France is the world’s largest tidal generating station. Its turbines spin with both incoming and outgoing tides.
Figure 18.14b

82. Tidal Power

83. Wave Energy There are several designs for wave energy stations.
In this one, air is compressed in a chamber with each incoming wave, driving a turbine to spin a generator.
Figure 18.15

84. Pros and Cons of Ocean Power
Renewable, as long as oceans behave as they always have
No greenhouse gas emissions
CONS
Development could take up large portions of coastline valuable for other uses
Could interfere with ecology of estuaries and intertidal shorelines

85. SOLAR ENERGY
                                                                                                                                                
                                                                                                                                                              
Source: DOE, USA

86. Solar Energy Use of energy from the Sun
Huge potential: Each day Earth receives enough sunlight to power human consumption for 27 years, if we could somehow capture it all.

87. Solar energy
Passive solar = designs buildings to maximize capture of sunlight in winter, but keep buildings cool in summer through window placement, absorbent materials…
Active solar = uses technological devices to focus, move, or store solar energy
Solar panels: dark heat-absorbing metal plates in glass-covered boxes, often mounted on roofs

88. Solar energy: Active solar
Portable solar cookers focus sun’s rays onto a small area—here, boiling water in Nepal. These are becoming popular throughout the developing world.
Figure 18.6

89. Numerous mirrors focus sunlight on a receiver atop a “power tower” in the California desert. This facility was the first to generate much solar power commercially.

90. Solar Furnace,
Ordellio, France

91. Application: Steel Production Facility
Source:

92. Solar Energy: Active Solar
Gaviotas, Colombia, uses solar panels in homes and businesses for heating, cooling, and water purification
(This photo is from Bogotá)
Figure 18.5

93. Solar Energy: PV Cells
Photovoltaic cells (PV cells) convert solar energy directly into electrical energy by making use of the photoelectric effect:
Sunlight strikes one of a pair of negatively-charged metal plates
Electrons migrate to opposing plates, and electric current is produced.
In PV cells, light strikes negatively charged phosphorus-
enriched silicon, and electrons migrate downward through silicon to positively charged boron-enriched silicon.

94. Solar Energy: PV Cells
Electrons move from the phosphorus side of the silicon plate to the boron side, creating electric current. PV cells are arranged in modules, panels, and arrays.
Figure 18.8

95. Solar Power Is little used, but fast growing
Currently only 0.04% of primary energy supply in the U.S.
Growing at 33% per year Cheaper technologies are taking off in developing countries.
More expensive technologies are growing more slowly in developed countries.

96. Pros and Cons of Solar Power
Renewable, as long as sun keeps on shining
Sun’s energy abundant, if technology can capture it
Allows for local decentralized control over power
No greenhouse gas emissions (although some are created in manufacture of technology)
CONS:
Not everywhere is sunny enough
Up-front investment cost is high; takes years to pay for itself

97. HYDROGEN POWER
Photo: WIRED

98. Hydrogen Hydrogen = simplest and most abundant element in universe
Could potentially serve as basis for clean, safe, efficient energy system
How it would work:
Electricity generated from intermittent renewable sources like wind or solar can be used to produce hydrogen.
Fuel cells can then use hydrogen to produce electrical energy for power.

99. Production of Hydrogen Fuel
Hydrogen gas (H2) does not exist freely on Earth.
We need to make it.
Electrolysis is the cleanest way:
Split water into hydrogen and oxygen:
2 H2O  2 H2 + O2
This can potentially be very clean, releasing no greenhouse gas emissions.

100. Production of Hydrogen Fuel
However, cleanliness of hydrogen production depends on source of electricity for electrolysis!
If the source of electricity needed for electrolysis is not clean (e.g., from coal), then greenhouse emissions will still occur.
Besides electrolysis, hydrogen can also be produced from organic molecules like fossil fuels. This entails greenhouse emissions.
H = 75% of the universe’s mass !
Combustion engines can be fuelled by hydrogen (Ballard Power – Canadian company and leader in this field)

101. Fuel Cells
In a fuel cell, hydrogen gas is used to produce electricity.
The reaction is simply the opposite of electrolysis:
2 H2 + O2  2 H2O
How it works:
Hydrogen molecules are stripped of electrons.
H+ ions move through a membrane.
Electrons complete a circuit, creating electricity.

102. Fuel cells
Figure 18.16

104. You can drink the exhaust !
O2 + 4H+ + 4e- => 2H2O
2H2 => 4H+ + 4e
NET REACTION: 2H2 + O2 => 2H2O
You can drink the exhaust !

105. Pros and Cons of Hydrogen Power
We will never run out of hydrogen
Can be clean and non toxic, with no greenhouse gas emissions
Fuel cells potentially convenient, safe, and efficient
CONS:
Depending on way hydrogen is produced, it may not be environmentally clean