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• 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!
Part One
Sources of Energy
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)
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
• Nonrenewable energy resources- fossil fuels (coal, oil, natural gas) and nuclear fuels.
Nonrenewable Energy
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
• 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.
Energy Use
Process of Energy Use
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,
Year
21002025195018751800
0
20
40
60
80
100C
ontr
ibution t
o t
ota
l energ
y
co
nsum
ption (
perc
ent)
Wood
Coal
Oil
Nuclear
Hydrogen
Solar
Natural gas
Part Two
Fossil Fuels
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)
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
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
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
North American Energy Resources
Coal
Gas
Oil
High potential
areas
MEXICO
UNITED STATES
CANADA
Pacific
Ocean
Atlantic
Ocean
Grand
Banks
Gulf of
Alaska
Valdez
ALASKA
Beaufort
Sea
Prudhoe Bay
Arctic
Ocean
Prince
William Sound
Arctic National
Wildlife RefugeTrans Alaska
oil pipeline
Fossil Fuel Reserves• Unequally distributed
• 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
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
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 least-industrialized nations
• The U.S has only 4.5% of the world’s population but consumes 20% of the world’s energy
Oil (% world production)
*2009
Natural Gas (% world production)
*2008
Coal(% world production)
*2008
Russia 11.8 Russia 21.3 China 39.2
Saudi Arabia 11.6 United States 18.6 United States 16.1
United States 10.8 Canada 5.5 India 7.8
Top Producing Nations
Top ConsumersOil
(% world production)*2009
Natural Gas (% world production)
*2008
Coal(% world production)
*2008
United States 22.3 United States 21.0 China 39.1
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
Fossil Fuel Reserves
• Developed countries:
– 1/3rd towards transportation
– 1/3rd on industry
– 1/3rd on all other uses
• Developing countries
– More energy goes towards subsistence activities
• Agriculture, farming, food prep, home heating
– Very little goes towards transportation
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
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
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
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
Two forms of coal mining
Mountain Top Removal
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
Coal• Remember?
– 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
• 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.
Electricity Generation
Electricity Generation
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
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
Burning Coal More Cleanly
Calcium sulfateand ash
Air
Air nozzles
Water
Fluidized bed
Steam
Flue gases
Coal Limestone
Advantages Disadvantages
Energy-dense Contains impurities
Plentiful Release impurities into air when burned
Easy to exploit by surface mining Trace metals like mercury, lead, and arsenic are found in coal
Technological demands are small Combustion leads to increased levels of sulfur dioxide and other air pollutants into the atmosphere.
Economic costs are low Ash is left behind
Easy to handle and transport Carbon is released into the atmosphere which contributes to climate change
Needs little refining
Advantages and Disadvantages of Coal
Natural Gas• Consists primarily of methane CH4
• Green house Gas
• Includes varying amounts of other volatile hydrocarbons
• Provides 1/4th 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
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
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
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
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
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 horseheadpumps– 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
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
Advantages Disadvantages
Contains fewer impurities and therefore emits almost no sulfur dioxide or particulates
When unburned, methane escapes into the atmosphere
Emits only 60% as much carbon dioxide as coal
Exploration of natural gas has the potential of contaminating groundwater
Ample Supply (125 years) Shipped across ocean as highly explosive LNG
Easily transported by pipelines
Advantages and Disadvantages Natural Gas
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
• 1/3rd 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
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
Energy Consumption of Oil per capita
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
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
Diesel oil
Asphalt
Greaseand wax
Naphtha
Heating oil
Aviation fuel
Gasoline
Gases
Furnace
Heated
crude oil
Extracted oil is refined to create many products
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
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
Primary and secondary oil extraction
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
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
Oil
• Hubbert’s peak-
– 1956 Shell Oil Geologist, M. King Hubbertcalculated 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
U.S. oil production has already peaked
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
Alaska’s North Slope
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”
Advantages Disadvantages
Convenient to transport and use Releases carbon dioxide into atmosphere
Relatively energy-dense Possibility of leaks when extracted and transported
Cleaner-burning than coal Possible water pollution
Releases sulfur, mercury, lead, and arsenic into the atmosphere when burned
Artificially low cost discourages search for alternatives
Ample supply for 40-90 years
Advantages and Disadvantages of Petroleum
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 Arabiein total oil reserves
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
Above Ground
Conveyor
Conveyor
Spent shale
Pipeline
Retort
Mined oil shale
Air
compressors
Shale oil
storage
Impurities
removedHydrogen
addedCrude oil Refinery
Air
injectionShale layer
Underground
Shale heated to vaporized kerogen, which is condensed to provide shale oil
Sulfur and nitrogen
compounds
Fig. 14.23, p. 341
Shale oil pumped to surface
Advantages Disadvantages
Moderate existing
supplies
Large potential
supplies
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
CO2 emissions
when burnedFig. 14.25, p. 342
Hydrogen
added
Impurities
removed
Synthetic
crude oilRefinery
Pipeline
Tar sand is mined. Tar sand is heated
until bitumen floats
to the top.
Bitumen vapor
Is cooled and
condensed.
Tar Sands
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)
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
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
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
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
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
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
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 (2nd to the Exxon Valdez)
– Nonpoint source pollution
• Automobiles, homes, industries, gas stations, etc
– Underground storage containers have leaked threatening drinking water supplies
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
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
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
The oil embargo of the 1970s caused panic• OPEC’s (Organization of Petroleum Exporting
Countries) oil embargo caused widespread panic and skyrocketing prices
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
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
The global trade in oil is lopsided
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
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
Our reliance on fossil fuels has consequences
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
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
CAFE standardsThe U.S. government has failed to enforce corporate average fuel efficiency (CAFE) standards, which mandate higher fuel efficiency in automobiles
Drilling in ANWR will not fill U.S. oil demand
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
We already have the technology needed• To increase fuel efficiency
• The efficiency of power plants– Cogeneration = excess heat produced during
electrical generation is used to heat buildings and produce other types of power
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
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