© 2011 pearson education, inc. chapter 14 energy from fossil fuels

© 2011 Pearson Education, Inc.

CHAPTER 14

Energy fromFossil Fuels


Global primary energy supply


Coal• Coal was substituted for wood fuel in the 1800s• Firewood for steam engines became scarce• It was used for steam engines, heating, cooking, and

industrial processes• By 1920, coal provided 80% of all U.S. energy

• Drawbacks of coal:• Smoke and fumes polluted cities• It is hazardous to mine and dirty to handle• Steam engines are bulky and hard to operate


Coal• China is the world’s leading coal producer• Builds two plants/week for electricity

• 49% of U.S. electricity comes from coal-fired power plants• U.S. coal supplies should last another 200 years

• Mining is hazardous• There are many coal-mining accidents and illnesses• Over 700 died from pneumoconiosis (CWP)—black

lung disease


Strip mining removes mountaintops• Strip mining allows quick, complete access to coal

veins• Dynamite breaks overlying areas• Giant power shovels remove overlying rocks and coal

• Environmental effects include deforestation and burying streams, erosion, acid leaching, and mine wastes (which affect surface and ground water)

• Federal regulations require reclamation (grading, replanting)• It takes decades for some areas to recover• Some arid areas may never recover


Oil Rules • By the late 1800s oil provided an alternative to coal• Due to the internal combustion engine, drilling, and

refinement of oil into fuels

• Benefits of oil• It was more convenient and burned more cleanly• The internal combustion engine is much lighter than a

steam engine

• Oil is now the major energy source for the world• Coal still predominates in eastern Europe and China


Oil spills and drills• With millions of gallons of oil in constant transit, it is

inevitable that spills will occur• In 1989, the Exxon Valdez spilled 11 million gallons• 2010 in the Gulf of Mexico--largest oil release to date• Drilling for oil in the Arctic National Wildlife Refuge

(ANWR) is an ongoing political firefight. It could result in major ecological disruption at a high cost—and for a relatively minor amount of oil.


Natural gas

• Natural gas is found wherever you find crude oil• Natural gas consists mainly of methane, which

produces carbon dioxide and water when burned• Burns more cleanly than coal or oil (but still gives off

CO2)• Pipelines now allow it to be transported, instead of

venting it to the atmosphere• It is used for heating, cooking, industry

• Gas satisfies 24% (U.S.) and 21% (world) of energy demand


Electrical power production• Electrical power: the amount of work done by an

electric current over a given time• Most energy we use comes from fossil fuels

• Energy carrier: the electricity itself that transfers energy from a primary energy source (coal, water power) to the point of use

• Electricity enables modern technological society• Computers, appliances, lights, the Internet

• More than 33% of fossil fuel production is used to generate electricity in the U.S.


Turbogenerators• Generating electricity requires a primary energy

source• Coal, oil, nuclear, solar—even geothermal energy • Those are used to boil water to produce steam, which

drives a turbine (a sophisticated paddle wheel)• The turbine is coupled to a generator that stores and

transmits the energy as electricity.• Turbogenerator: the turbine and generator• Burning gas drives the turbine directly• Windmills (wind generators) have wind-driven turbines• At a dam, falling water turns a turbine, generating

hydroelectric power. This is CO2-free.


Electricity demand vs. supply• In the U.S., demand is rising faster than supply• Reserve capacity has declined to 15%• Summer heat waves are the greatest cause of

sudden increased demand• Utilities are being pushed to the edge of their ability to

provide electricity on demand

• Another serious problem: antiquated systems controlling the power transmission grid, which connects power sources to users


Blackout• In 2008 the largest blackout in U.S. history left 50

million people in eight states and two Canadian provinces without power• It started when power lines brushed against tree

branches• It cost the economies of the two countries $30 billion

• A “smart grid” can prevent major blackouts• It monitors problems, reacts to trouble, and isolates

troubled areas to prevent cascading failures• The U.S. Department of Homeland Security rates this

as one of its highest priorities


Clean energy?• Electric power is clean and nonpolluting only at the

point of use. Electric cars don’t directly emit CO2, but they use electricity—often that was produced by burning fossil fuels.

• Electricity is an expensive way to heat homes• It is generated mainly from fossil fuels and nuclear• Coal-burning plants are the major source of U.S.

electricity• Unfortunately, they contribute to the formation of acid

rain and greenhouse gases

• Nuclear energy is cleaner but distrusted• Potential for accidents, issues with the mining of

uranium ore and the disposal of waste


Matching sources to uses

• Some forms of energy do well in some uses but not others

• Nuclear and coal will not reduce the demand for oil• Most transportation (cars, trucks, tractors, planes, trains)

depends on oil for fuel


Energy flow• Transportation equals 29% of U.S. energy use • Depends mainly on petroleum

• Nuclear, coal, water power are used to produce electricity

• Natural gas and oil are more versatile sources—they can be used for either electricity or for vehicle fuel

• Saving energy is equivalent to increasing energy supplies. So, conservation stretches our finite energy supply for future generations.


Exploiting crude oil• U.S. coal, natural gas, & nuclear power supplies are

adequate• But we import 66% of our crude oil

• Increasing dependence on imported oil causes trade imbalances, military actions, economic disruptions, coastal oil spills

• Fossil fuels (crude oil, coal, natural gas) were formed 100–500 million years ago in swamps and shallow seas. We have used about half of that oil in the past century. When it’s gone, it’s gone!


Crude oil reserves vs. production• Proved reserves: an accurate estimate of how much

oil can be economically obtained from a field

• The Middle East has 61% of proved reserves• The U.S. and others will depend on this area for oil

• 1 barrel = 42 gallons

• Most of the world’s large oil deposits have now been located, mapped, and “proved.” It is unlikely that we will “find” significant, new, large oil reserves now.


Recovery• Production from a field does not proceed at a steady

rate• Oil is trapped in pore spaces of sedimentary rock

• At first, pressurized oil may gush from a well• But only 25% of oil can be removed using

conventional pumping (primary recovery)

• Secondary recovery can remove up to 50% of oil• By injecting steam or brine into the wells. It is like

trying to get all the honey out of a honeycomb.• Enhanced recovery involves techniques such as

injecting carbon dioxide to break up oil, allowing even more oil to be obtained. This is expensive, though.


Declining U.S. reserves• Up to 1970, the U.S. was oil independent• In 1970, production decreased but consumption

INCREASED.

• The U.S., Europe, and Japan increased imports from the Middle East during the 70’s and 80’s

• Imported crude oil was cheap and plentiful

• The U.S. and other industrialized countries steadily increased their dependence on imported oil


Adjusting to higher prices• In response to higher prices, the U.S. and other

nations• Increased domestic production, e.g., the Alaskan

pipeline, re-opening old fields• Increased fuel efficiency standards, e.g., lowered

speed limits in some places (to 55 mph)• Promoted appliance and building efficiencies• Developed alternative energy sources• Created a strategic oil reserve in Louisiana to store

702 million barrels of oil (33 days of oil at 21 million barrels/day use)

• …but have we really attempted to conserve energy?


Back to the future• Prices rose to over $140/barrel in 2008• People reduced driving and bought hybrid cars• Oil companies had record profits• Food prices soared• Congress raised efficiency standards and called for

increased renewable fuels


The consequences of U.S. dependency• U.S. dependency on foreign oil has three costs:• Costs of buying oil• Risk of supply disruptions (e.g., political instability in

the Middle East)• Ultimate resource limitations

• In 2000, the U.S. paid $300 billion in oil imports• Since 2000, imports increased 24% and oil’s price

rose fivefold


Persian Gulf oil• The U.S. keeps a military capability in the region• Recognizes the political instability• Ensures access to Persian Gulf oil

• Saddam Hussein of Iraq invaded Kuwait (1990)• U.S.-led Persian Gulf War threw Hussein out• The U.S.’s ongoing presence angered radical Islamic

Al Qaeda• Led to the September 11, 2001 attack on the U.S.


The U.S. still relies on oil exports• Military costs represent a significant government

subsidy to oil “costs”• Costing money and human lives

• The U.S. is now importing 44% of our oil from nations other than OPEC nations• Canada, Mexico, Colombia, Russia, Nigeria• These are politically stable • But production in those regions is decreasing

• For now, we continue to be dependent on OPEC and Persian Gulf oil.


Other fossil fuels: natural gas• The U.S. imports 16.5% of natural gas used• Most comes from Canada

• Gas is used in industry, residential, and electrical power generation

• Costs fluctuate with supply and demand and season• U.S. proved reserves = 9 years’ worth• Worldwide, there is four times as much nat. gas as oil

• Natural gas is piped or liquefied (liquid natural gas [LNG])• New LNG facilities are seen as security and safety

hazards


Natural-gas-run cars• Cars can run on natural gas with installation of a gas

tank and engine modifications• Natural gas is a clean-burning fuel• Releases carbon dioxide and water • But not hydrocarbons or sulfur oxides

• Used in buses and car fleets in the U.S. • But there are limited service stations• Detroit automakers no longer sell these cars

• The fleet is growing in Europe• The U.S. needs stronger public-policy support


Synthetic oil (at a price)• The Fischer-Tropsch process turns natural gas into

synthetic oil• It is only 10% more expensive than oil

• Natural gas can be turned into diesel and home-heating fuels

• Drilling in the lower 48 states occurs in sensitive areas• Environmental damage from roads, wells, and pipelines• Federal lands are being drilled

• A 3,600-mile gas pipe is needed to bring gas from Alaska and Canada• Costing $25 billion and causing environmental harm


Oil shale• Found in Colorado, Utah, Wyoming• Oil shale: a fine sedimentary rock containing kerogen,

a waxlike hydrocarbon• Refining can produce gasoline and other petroleum

products• One ton of shale produces ½ barrel of oil• Mining, transportation, and waste disposal are

prohibitive

• Oil companies consider developing oil shale deposits;• They face stiff opposition due to production of air and

water pollution during the processing of oil shale.• Development must get local and state approval.


Oil sand• Oil sand: a sedimentary material containing bitumen,

a hydrocarbon that can be refined like oil; the oil sand is heated to melt and collect the bitumen.

• Alberta, Canada has the largest deposits (152 BBs)• The cost is competitive with oil

• Mining oil sand causes significant environmental damage• 82,000 acres of boreal forest and wetlands have

already been heavily disturbed

• Oil shale and oil sand will inevitably be used in the U. S. and Canada when oil prices climb dramatically.


Security threats: global climate change• Burning fossil fuels releases CO2

• Coal produces the most greenhouse gas emissions• Natural gas produces the least (of the fossil fuels)

• Increasing carbon dioxide levels likely increases average global temperatures

• Melting ice caps and raising sea levels• Causing more severe storms, droughts, heat waves

• The U.S. is a leading producer of greenhouse gases

since it consumes the most fossil fuels (see next slide)


Annual carbon dioxide emissions from fossil fuels


Energy-saving technologies are here!• CHP facilities install a small power plant to produce

electricity• Heats the building with “waste” heat• Achieves an 80% efficiency

• The combined-cycle natural-gas unit generates electricity• One turbine burns natural gas• A second turbine runs on excess steam from the

other turbine• Achieves 50% efficiency at half the cost and less

pollution


Final thoughts

• A human population of 7 billion demands energy.

• Two pathways can develop non-fossil-fuel energies:• Nuclear power (though it needs technological

solutions to the disposal of radioactive waste)

• Renewable energy, such as solar and wind power: needs government support

© 2011 pearson education, inc. chapter 14 energy from fossil fuels

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