Do Now. Make sure you are signed up for THIS SATURDAY S study sesh. Grab a chromebook and go to my website, Unit 10, Energy!

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1 Do Now Make sure you are signed up for THIS SATURDAY S study sesh Tinyurl.com/APES-study-3-25 Grab a chromebook and go to my website, Unit 10, Energy!

2 Part One Sources of Energy

3 Sources of Energy We use energy to heat and light our homes, power machinery, fuel our vehicles and produce plastics, pharmaceuticals, synthetic fibers etc etc Renewable vs. nonrenewable Nonrenewable sources cannot be renewed in our life time (forms slower than we use it)

4 Energy Source Description Type Crude oil Fossil fuel extracted from ground (liquid) Nonrenewable Natural Gas Fossil fuel extracted from ground (gas) Nonrenewable Coal Fossil fuel extracted from ground (solid) Nonrenewable Nuclear Energy from atomic nuclei of uranium Nonrenewable Biomass energy Energy stored in plant matter from photosynthesis Renewable Hydropower Energy from running water Renewable Solar Energy Energy from sunlight directly Renewable Wind Energy Energy from the wind Renewable Geothermal energy Earth s internal heat rising from core Renewable Tidal and Wave energy Energy from tidal forces and ocean waves Renewable

5 Nonrenewable Energy Nonrenewable energy resources- fossil fuels (coal, oil, natural gas) and nuclear fuels.

6 We use a variety of energy sources Sun is the ultimate source of all energy Solar radiation helps drive wind patterns and the hydrologic cycle Harness the suns energy with solar power technology We use wood and other biomass as a fuel source (made possible with photosynthesis) Plants that die and are preserved can store chemical energy in the form of fossil fuels

7 Energy Use Commercial energy sources- those that are bought and sold, such as coal, oil and natural gas. Subsistence energy sources- those gathered by individuals for their own use such as wood, charcoal and animal waste.

8 Process of Energy Use

9 Sources of Energy We will break energy up into: Fossil fuels Oil, coal and natural gas Conventional alternative energy Nuclear energy, bioenergy, hydroelectric Renewable energy alternatives Solar, wind, geothermal, hydrogen,

10 Contribution to total energy consumption (percent) 100 Wood 80 Coal 60 Natural gas Oil Nuclear Hydrogen Solar Year

11 Part Two Fossil Fuels

12 Split Into Groups! You and your group are going to make a comprehensive poster over a specific section of the notes. 1. Fossil Fuels (13-23) 2. Coal (24-35) 3. Natural Gas (36-44) 4. Oil (45-62) 5. Other Fossil Fuels (63-69) 6. Environmental and Economic Impacts (70-84)

13 Fossil Fuels Fossil Fuels- highly combustible substances formed from the remains of organisms from past geologic ages Oil, Coal and Natural Gas Nonrenewable Since the industrial revolution we have replaced burning biomass with fossil fuels

14 Fossil Fuels Forms when organic matter undergoes slow anaerobic decomposition deep under sediments Typically happens at the bottom of lakes, swamps and shallow seas Forms kerogen Geothermal heating acts on the kerogen to create crude oil and natural gas Coal is formed when plant matter is compacted so tightly there is little decomposition

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16 Fossil fuels are our dominant source of energy Fossil fuels have replaced biomass as our dominant source of energy The high-energy content of fossil fuels makes them efficient to burn, ship, and store These fuels generate electricity = a secondary form of energy that is easier to transfer and apply to a variety of uses

17 North American Energy Resources Gulf of Alaska ALASKA Trans Alaska oil pipeline Prince William Sound Valdez Prudhoe Bay Beaufort Sea Arctic National Wildlife Refuge Arctic Ocean Coal Gas Oil High potential areas CANADA Pacific Ocean UNITED STATES Grand Banks Atlantic Ocean MEXICO

18 Fossil Fuel Reserves Unequally distributed Oil (% world reserves) 2010 Natural Gas (% world reserves) 2010 Coal (% world reserves) 2010 Saudi Arabia 19.8 Russia 23.7 United States 28.9 Venezuela 12.9* Iran 15.8 Russia 19.0 Iran 8.6 Qatar 13.5 China 13.9 *If oil sands are included, Canada ranks second in oil reserves Oil/tar sands- deposits that can be mined from the ground, consisting of moist sand and clay containing 1-20% bitumen Crude oil deposits that have been degraded and chemically altered

19 Fossil Fuel Reserves Developed nations generally consume far more energy than developing regions The most industrialized nations use up to 100 times more energy per person than to leastindustrialized nations The U.S has only 4.5% of the world s population but consumes 20% of the world s energy

20 Oil (% world production) *2009 Oil (% world production) *2009 Top Consumers Natural Gas (% world production) *2008 United States 22.3 United States 21.0 China 39.1 Top Producing Nations Natural Gas (% world production) *2008 Russia 11.8 Russia 21.3 China 39.2 Coal (% world production) *2008 Saudi Arabia 11.6 United States 18.6 United States 16.1 United States 10.8 Canada 5.5 India 7.8 Coal (% world production) *2008 China 9.8 Russia 15.2 United States 15.5 Japan 5.2 Iran 3.8 India 8.8 India 3.6 Japan 3.2 Germany 3.7 Russia 3.4 United Kingdom 3.1 Russia 3.7

21 Fossil Fuel Reserves Developed countries: 1/3 rd towards transportation 1/3 rd on industry 1/3 rd on all other uses Developing countries More energy goes towards subsistence activities Agriculture, farming, food prep, home heating Very little goes towards transportation

22 Fossil Fuel It takes energy to make energy We have to evaluate the energy invested (infrastructures, roads, vehicles, storage tanks, pipelines, etc) when looking at different energy sources

23 Fossil Fuels Net energy is the difference between energy returned and energy invested: Net energy= Energy Returned Energy invested EROI- energy returned on investment EROI = Energy returned/energy invested The higher the EROI ratio the more energy we receive from each unit of energy that we invest

24 Coal Most abundant Provides 29% of global commercial energy consumption Generally formed from woody plant material Scientists estimate the Earth holds enough coal to supply our society for a few hundred more years (much longer than oil or natural gas) Given as Christmas gifts to naughty children

25 Coal Mining Strip mining- heavy machinery scrapes away huge amounts of earth to expose coal Subsurface mining- digging vertical shafts and blasting out networks of horizontal tunnels to follow seams (layers) of coal Mountaintop removal mining- several hundred vertical feet of mountaintop may be removed to allow recovery of entire seams Appalachian Mountains

26 Two forms of coal mining

27 Mountain Top Removal

28 Coal China and the US are the primary producers and consumers of coal Production (% world) Consumption (% world) China 39.2 China 39.1 United States 16.1 United States 15.5 India 7.8 India 8.8 Australia 6.0 Germany 3.7 Russia 4.9 Russia 3.7

29 Remember? Coal Peat, lignite, bituminous and anthracite (Least compressed Most compressed) Reverse alphabetical order The more coal is compressed the greater the carbon content = greater energy content per unit

30 Electricity Generation The burning fuel from coal transfers energy to water, which becomes steam. The kinetic energy contained within the steam is transferred to the blades of a turbine, a large device that resembles a fan. As the energy in the steam turns the turbine, the shaft in the center of the turbine turns the generator. This mechanical motion generates energy.

31 Electricity Generation

32 Coal Contains impurities such as sulfur, mercury, arsenic and other trace metals Sulfur content depends on whether the goal was formed in fresh or salt water sediments US has higher sulfur contents because it was formed in marine sediments where sulfur from sea water was present China has even higher sulfur content

33 Coal The impurities are emitted in smoke from its combustion unless pollution control measures are in place. Clean Coal technologies help filter out pollutants from the combustion process and toxic ash residue is taken to hazardous waste disposal sites

34 Burning Coal More Cleanly Coal Limestone Steam Flue gases Fluidized bed Water Air Air nozzles Calcium sulfate and ash

35 Advantages and Disadvantages of Coal Advantages Energy-dense Plentiful Easy to exploit by surface mining Technological demands are small Economic costs are low Easy to handle and transport Needs little refining Contains impurities Disadvantages Release impurities into air when burned Trace metals like mercury, lead, and arsenic are found in coal Combustion leads to increased levels of sulfur dioxide and other air pollutants into the atmosphere. Ash is left behind Carbon is released into the atmosphere which contributes to climate change

36 Natural Gas Consists primarily of methane CH 4 Green house Gas Includes varying amounts of other volatile hydrocarbons Provides 1/4 th of global commercial energy consumption Favored because it is versatile and clean burning Emits half as much carbon dioxide per unit of energy produced as coal and 2/3rds as much as oil

37 Natural Gas Natural Gas can arise from either two processes: Biogenic gas- created at shallow depths by anaerobic decomp, swamp gas Pure methane Thermogenic gas- created from compression and heat deep under the ground Kerogen is formed With high temperatures and pressure natural gas is formed from the kerogen Methane and other small amounts of other gases

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39 Natural Gas One source of Biogenic gas is the decay process in landfills Now its captured in landfills and sold Decreases energy waste, is profitable and reduces the atmospheric release of methane

40 Natural Gas Most gas extracted commercially is thermogenic and is found above deposits of crude oil or seams of coal so its extraction often accompanies the extraction of those fossil fuels

41 Natural Gas Natural gas goes to waste as it escapes from coal mines or oil wells Coalbed methane- comes from coal seams and commonly leaks to the atmosphere during mining Engineers try to capture this for energy Oil drilling areas that are remove (transportation would be too expensive) methane is just burned off

42 Natural gas extraction becomes more challenging The first gas fields simply required an opening and the gas moved upward Most remaining fields require pumping by horsehead pumps moves a rod in and out of the shaft creating pressure to pull both natural gas and crude oil to the surface Most accessible reserves have been depleted Gas is accessed by sophisticated techniques such as fracturing, which pumps high-pressure salt water into rocks to crack them

43 Natural Gas Fracking is now more commonly used (hydrolic fracturing techniques) Pump salt water under high pressure into the rocks to crack them Sand or small glass beads are inserted to hold the cracks open to release the methane Uses large amounts of water and chemicals whose names and effects do not have to be released to the public

44 Advantages and Disadvantages Natural Gas Advantages Contains fewer impurities and therefore emits almost no sulfur dioxide or particulates Emits only 60% as much carbon dioxide as coal Ample Supply (125 years) Disadvantages When unburned, methane escapes into the atmosphere Exploration of natural gas has the potential of contaminating groundwater Shipped across ocean as highly explosive LNG Easily transported by pipelines

45 Offshore drilling Drilling for natural gas, as well as for oil, takes place on land but also the seafloor Offshore drilling requires technology that can withstand the forces of wind, waves and ocean currents Some drilling platforms are fixed, some are floating 1/3 rd of the oil and 13% of natural gas extracted in the US comes from offshore drilling Primarily in the Gulf of Mexico Southern California as well

46 Oil World s most used fuel Accounts for 35% of the world s commercial energy consumption Our global society consumes nearly 200 gallons of oil each year for every man, woman and child The U.S. consumes 23% of the world s oil but China and India are increasing driving world demand

47 Energy Consumption of Oil per capita

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49 Oil Oil, or crude oil, forms within a window of temperature and pressure conditions found 1-2 miles below the surface Liquid petroleum is also known as crude oil Does contain natural gas- usually burned off onsite Oil and gasoline are idea for mobile combustion (cars) Must be transported by pipeline

50 Oil Crude oil can be refined into Tar, asphalt, gasoline, diesel and kerosene These are distinguished by the temperature at which they boil and therefore can be separated by heating the petroleum Heated crude oil Furnace Gases Gasoline Aviation fuel Heating oil Diesel oil Naphtha Grease and wax Asphalt

51 Extracted oil is refined to create many products

52 Oil At oil refineries crude oil is boiled causing its many hydrocarbon constituents to proceed up the distillation column Heavy oils are separated from lighter oils

53 Oil Drilling Oil is typically under pressure from the rock or trapped gas above it and below by ground/groundwater Once drilled oil will often rise to the surface on its own because of that pressure Primary extraction- initial drilling and pumping of available oil Secondary extraction- solvents are used to flush out with water to remove the additional oil

54 Primary and secondary oil extraction

55 Oil Scientists have calculated that we have already extracted half of the world s oil reserves So far we have used up about 1.1 trillion barrels of oil One barrel is 42 gallons Most estimates suggest a little more than 1 trillion barrels remain Last about 40 more years

56 Oil We will have our oil crisis when peak oil is met When the rate of production comes to a peak than declines If demand increases after an oil peak we will experience oil shortages immediately Experts worry this might happen in the next few decades

57 Oil Hubbert s peak Shell Oil Geologist, M. King Hubbert calculated the US oil production would peak in 1970 It was ridiculed at the time but proved to be accurate US oil production peaked in 1970 and has continued to fall ever since

58 U.S. oil production has already peaked

59 Central Case: oil or wilderness on Alaska s North Slope? Alaska s remote North Slope represents a pristine wilderness to some and untapped oil riches to others The Arctic National Wildlife Refuge is the focus of intense debate over whether the 1002 Area should be opened to drilling Opponents fear that drilling will sacrifice the nation s national heritage for little gain

60 Alaska s North Slope

61 Alaska s North Slope consists of three regions The National Petroleum Reserve Alaska (NPR-A) Intended to remain untapped unless the nation faced an emergency It has been opened recently for drilling Prudhoe Bay consists of state lands that are drilled for oil that is transported via the trans-alaska pipeline to the port of Valdez The Arctic National Wildlife Refuge (ANWR) is federal land set aside for wildlife and to preserve pristine ecosystems It has been called the Serengeti of North America

62 Advantages and Disadvantages of Petroleum Advantages Convenient to transport and use Relatively energy-dense Cleaner-burning than coal Releases sulfur, mercury, lead, and arsenic into the atmosphere when burned Ample supply for years Disadvantages Releases carbon dioxide into atmosphere Possibility of leaks when extracted and transported Possible water pollution Artificially low cost discourages search for alternatives

63 Other Fossil Fuels Oil sands/tar sands Deposits of moist sand and clay containing 1-20% bitumen (a thick, heavy, tar-like form of petroleum) Too thick to be extracted by drilling so they are generally removed by strip mining Found mainly in Easter Venezuela and northeastern Alberta, Canada More profitable than crude oil If oil sands are included in proven reserves of petroleum then Canada is only second to Saudi Arabie in total oil reserves

64 Other Fossil Fuels Oil Shale- Sedimentary rock filled with kerogen Can be processed to produce liquid petroleum Formed by the same process that forms crude oil Typically mined Oil shale can be burned directly, like coal 40% of oil shale reserves are found in the US Federally owned land in Colorado, Wyoming and Utah

65 Mined oil shale Retort Above Ground Conveyor Conveyor Spent shale Pipeline Air compressors Shale oil storage Impurities removed Sulfur and nitrogen compounds Hydrogen added Crude oil Refinery Air injection Shale layer Shale oil pumped to surface Underground Shale heated to vaporized kerogen, which is condensed to provide shale oil Fig , p. 341

66 Advantages Moderate existing supplies Large potential supplies Disadvantages High costs Low net energy yield Large amount of water needed to process Severe land disruption from surface mining Water pollution from mining residues Air pollution when burned CO 2 emissions when burned Fig , p. 342

67 Tar sand is mined. Tar sand is heated until bitumen floats to the top. Bitumen vapor Is cooled and condensed. Impurities removed Hydrogen added Synthetic crude oil Refinery Pipeline Tar Sands

68 Other Fossil Fuels Methane Hydrate- An ice like solid consisting of molecules of methane embedded in a crystal lattice of water molecules Stable at temp/pressures found in sediments on the Arctic seafloor Scientists believe their to be immense amounts of methane hydrate on Earth May hold twice as much carbon as all known deposits of oil, coal and natural gas combined We do not know how to extract safely- it could lead to a release of gas that could cause massive landslides, tsunamis as well as more methane (a GHG)

69 Other Fossil Fuels Drawbacks to these alternative fossil fuels Low net energy value Severe environmental impacts Mining, waterway pollution Emit just as much carbon dioxide, methane and air pollutants as our current use of coil, oil and natural gas

70 Environmental Impacts and Solutions Fossil fuels have increased the ease of travel, lengthen our time spans, boosted our standard of living (materialistically) They have also harmed the environment Concern of environmental impacts have forced scientists, environmentalists, businesspeople and policy makers to look towards renewable energy

71 Pollution and Climate Change When we burn fossil fuels we alter the natural carbon cycle We take carbon that has been naturally sequestered into a long-term reservoir underground and release it into the air The carbon dioxide made in the process is a GHG Warms our planet The methane is released as well which is also a GHG

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73 Pollution and Climate Change Human health concerns- Gasoline combustion pollutants irritate the nose, throat and lungs Benzene and toluene (hydrocarbons) are carcinogenic Hydrogen sulfide (evaporates from crude oil) causes asphyxiation and is an irritant to the eyes and throat Crude oil contains trace amounts of arsenic This is a problem for workers at drilling operations and refineries Causes cancer

74 Pollution and Climate Change Combustion of oil in our vehicles and coal in our power plants releases sulfur dioxide and nitrogen oxides (create photochemical smog and acid rain) Combustion of coal with a high level of mercury content emits mercury that can bioaccumulate

75 Scientists anticipate negative impacts in ANWR Some scientists anticipate damage if ANWR is drilled Vegetation killed Degraded air and water quality Roads fragment habitat Prospecting and drilling disrupts wildlife Other scientists say little harm will be done ANWR will be developed with environmentally sensitive technology and approaches

76 Water Pollution Mining and other fuel extraction processes can pollute waterways Massive oil spills from tankers or drilling platforms Deepwater Horizon being the largest accidental oil spill in history (2 nd to the Exxon Valdez) Nonpoint source pollution Automobiles, homes, industries, gas stations, etc Underground storage containers have leaked threatening drinking water supplies

77 Coal Mining Devastates Natural Systems Strip mining destroys large habitats and causes soil erosion Can cause chemical runoff in a process called acid drainage When sulfide minerals in newly exposed rock reacts with oxygen and rainwater to produce sulfuric acid Mountain top removal Tons of rocks and soil are removed from a mountain tops which can cause landslides which degrade/destroy habitats and creek beds can be clogged/polluted

78 Oil and Gas Extraction Modify the Environment To drill an oil field you need infrastructure Roads, housing for workers, transport pipelines and waste piles for removed soil Ponds that collect toxic sludge may be created Groundwater needs to be pumped and dumped

79 Nations can become dependent on foreign energy This causes unrest and conflict We are vulnerable to supplies becoming unavailable or expensive The U.S. imports 60% of its crude oil, meaning other nations control our energy supplies

80 The oil embargo of the 1970s caused panic OPEC s (Organization of Petroleum Exporting Countries) oil embargo caused widespread panic and skyrocketing prices

81 Oil supply and prices affect nation s economies Hurricanes Katrina and Rita destroyed offshore drilling systems and spiked oil prices Because the politically volatile Middle East has the majority of oil reserves, crises are a constant concern for the U.S. Despite political disagreements, the U.S. has a close relationship with Saudi Arabia because Saudi Arabia owns 22% of the world s oil reserves

82 The U.S. enacted policies to reduce foreign oil The U.S. government enacted policies to diversify its oil supply It imports oil from several countries The U.S. is developing its own reserves Proposed drilling in ANWR, despite charges that drilling won t help much Resuming extraction at currently closed sites Research into renewable energy sources The Strategic Petroleum Reserve stockpiles oil in caverns under Louisiana for use when world supplies run out But this reserve equals just one month s supply

83 The global trade in oil is lopsided

84 Residents may or may not benefit from reserves Extraction can benefit residents of the area with: Increased job opportunities Trickling down of profits Citizens in Alaska are paid dividends by the government But residents are not always compensated for pollution and displacement

85 How will we convert to renewable energy? Fossil fuel supplies are limited and their use has consequences Nations have several options for future energy use Continue relying on fossil fuels until they are no longer available Increase funding to develop alternative energy sources dramatically Steer a middle course and gradually reduce our reliance on fossil fuels

86 Our reliance on fossil fuels has consequences

87 Energy conservation Energy conservation = the practice of reducing energy use to: Extend the life of our nonrenewable energy supplies Be less wasteful Reduce environmental impact

88 Energy conservation has followed need Conservation usually only occurs in time of need OPEC embargo of 1973 drastically increased conservation, but it didn t last Government research into alternative energy sources decreased The failure to improve fuel economy has increased our oil consumption Taxes on gasoline are extremely low, meaning that gasoline does not account for its substantial external costs on production and consumption

89 CAFE standards The U.S. government has failed to enforce corporate average fuel efficiency (CAFE) standards, which mandate higher fuel efficiency in automobiles

90 Drilling in ANWR will not fill U.S. oil demand

91 Personal choice and efficiency Energy conservation can be accomplished in two ways: Individuals can make conscious choices to reduce energy consumption in everyday life and drastically increase conservation Driving less, turning off lights, buying efficient machines Society can make energy-consuming devices more efficient Also helps reduce the enormous amounts of energy wasted every day

92 We already have the technology To increase fuel efficiency needed The efficiency of power plants Cogeneration = excess heat produced during electrical generation is used to heat buildings and produce other types of power

93 Efficiency among consumer products Improvements in home design can reduce energy required to heat and cool them Scores of appliances have been reengineered to increase energy efficiency Consumers need to vote with their wallets by buying energy-efficient products

94 Conservation and renewable energy is needed Effective energy conservation could save 6 million barrels of oil a day Conserving energy is better than finding a new reserve It decreases environmental impacts while extending our access to fossil fuels The only sustainable way of reliable supply of energy is to ensure sufficiently rapid development of renewable energy