Strona główna Alternative Energy [3 Vols]
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Alternative Energy [3 Vols]

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Alternative Energy

Alternative Energy
Volume 1

Neil Schlager and Jayne Weisblatt, editors

Alternative Energy
Neil Schlager and Jayne Weisblatt, Editors

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Alternative energy / Neil Schlager and Jayne Weisblatt, editors.
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Includes bibliographical references and index.
ISBN 0-7876-9440-1 (set hardcover : alk. paper) –
ISBN 0-7876-9439-8 (vol 1 : alk. paper) –
ISBN 0-7876-9441-X (vol 2 : alk. paper) –
ISBN 0-7876-9442-8 (vol 3 : alk. paper)
1. Renewable energy sources. I. Schlager, Neil, 1966- II. Weisblatt, Jayne.
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Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Words to Know . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
Introduction: What are Fossil Fuels? . . . . . . . . . . . . . . . . . . .
Petroleum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Natural Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coal Gasification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liquefied Petroleum Gas: Propane and Butane . . . . . . . . . . . .
Methanol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Methyl Tertiary-Butyl Ether . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Bioenergy? . . . . . . . . . . . . . . . . . . . . . .
Solid Biomass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Biodiesel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vegetable Oil Fuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Biogas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ethanol and Other Alcohol Fuels . . . . . . . . . . . . . . . . . . . . . .
P-Series Fuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Geothermal Energy?. . . . . . . . . . . . . . . 097
Agricultural Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Aquacultural Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Alternative Energy



Geothermal Power Plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Geothermal Heating Applications . . . . . . . . . . . . . . . . . . . . . .
Industrial Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Hydrogen Energy? . . . . . . . . . . . . . . . .
Historical Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Producing Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transporting Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Distributing Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storing Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Future Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Nuclear Energy?. . . . . . . . . . . . . . . . . .
Historical Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How Nuclear Energy Works . . . . . . . . . . . . . . . . . . . . . . . . . .
Current and Future Technology . . . . . . . . . . . . . . . . . . . . . . .
Benefits and Drawbacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Environmental Impact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Economic Impact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Societal Impact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Barriers to Implementation or Acceptance . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Solar Energy? . . . . . . . . . . . . . . . . . . . .
Passive Solar Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Daylighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transpired Solar Collectors . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solar Water Heating Systems . . . . . . . . . . . . . . . . . . . . . . . . . .
Photovoltaic Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dish Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Trough Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solar Ponds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solar Towers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solar Furnaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Water Energy? . . . . . . . . . . . . . . . . . . . 261
Hydropower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275

Alternative Energy


Hydroelectricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ocean Thermal Energy Conversion. . . . . . . . . . . . . . . . . . . . .
Tidal Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ocean Wave Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction: What is Wind Energy? . . . . . . . . . . . . . . . . . . .
How Wind Energy Works . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Current and Future Technology . . . . . . . . . . . . . . . . . . . . . . .
Benefits and Drawbacks of Wind Energy . . . . . . . . . . . . . . . .
Wind Turbines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Current and Potential Uses . . . . . . . . . . . . . . . . . . . . . . . . . . .
Issues, Challenges, and Obstacles . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Climate Responsive Buildings . . . . . . . . . . . . . . . . . . . . . . . . .
Green Building Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Energy Efficiency and Conservation in the Home . . . . . . . . .
Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hybrid Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leaving an Energy Footprint on the Earth . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Is Alternative Energy Enough? . . . . . . . . . . . . . . . . . . . . . . . .
Dreams of Free Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Perpetual Motion, an Energy Fraud and Scam . . . . . . . . . . . .
Advances in Electricity and Magnetism. . . . . . . . . . . . . . . . . .
Zero Point Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solar Power Satellites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
No Magic Bullets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


WHERE TO LEARN MORE . . . . . . . . . . . . . . . . . . . . . . . . . . xxix
INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxxix

Alternative Energy



Alternative Energy offers readers comprehensive and easy-to-use
information on the development of alternative energy sources.
Although the set focuses on new or emerging energy sources, such
as geothermal power and solar energy, it also discusses existing
energy sources such as those that rely on fossil fuels. Each volume
begins with a general overview that presents the complex issues
surrounding existing and potential energy sources. These include
the increasing need for energy, the world’s current dependence on
nonrenewable sources of energy, the impact on the environment of
current energy sources, and implications for the future. The overview will help readers place the new and alternative energy sources
in perspective.
Each of the first eight chapters in the set covers a different
energy source. These chapters each begin with an overview that
defines the source, discusses its history and the scientists who
developed it, and outlines the applications and technologies for
using the source. Following the chapter overview, readers will find
information about specific technologies in use and potential uses
as well. Two additional chapters explore the need for conservation
and the move toward more energy-efficient tools, building materials, and vehicles and the more theoretical (and even imaginary)
energy sources that might become reality in the future.
Each volume of Alternative Energy includes the overview, a glossary called "Words to Know," a list of sources for more information,
and an index. The set has 100 photos, charts, and illustrations to

Alternative Energy


enliven the text, and sidebars provide additional facts and related
U•X•L would like to thank several individuals for their assistance with this set. At Schlager Group, Jayne Weisblatt and Neil
Schlager oversaw the writing and editing of the set. Michael J.
O’Neal, Amy Hackney Blackwell, and A. Petruso wrote the text
for the volumes.
In addition, U•X•L editors would like to thank Dr. Peter Brimblecombe for his expert review of these volumes. Dr. Brimblecombe teaches courses on air pollution at the School of Environmental Sciences, University of East Anglia, United Kingdom. The
editors also express their thanks for last minute contributions,
review, and revisions to the final chapter on alternative and potential energy resources to Rory Clarke (physicist, CERN), Lee Wilmoth Lerner (electrical engineer and intern, NASA and the Fusion
Research Laboratory at Auburn University), Larry Gilman (electrical engineer), and K. Lee Lerner (physicist and managing director,
Lerner & Lerner, LLC).
We welcome your comments on Alternative Energy and suggestions for future editions of this work. Please write: Editors, Alternative Energy, U•X•L, 27500 Drake Rd., Farmington Hills, Michigan 48331-3535; call toll free: 1-800-877-4253; fax: 248-699-8097;
or send e-mail via

Alternative Energy


Words to Know

acid rain: Rain with a high concentration of sulfuric acid, which can
damage cars, buildings, plants, and water supplies where it falls.
adobe: Bricks that are made from clay or earth, water, and straw,
and dried in the sun.
alkane: A kind of hydrocarbon in which the molecules have the
maximum possible number of hydrogen atoms and no double
anaerobic: Without air; in the absence of air or oxygen.
anemometer: A device used to measure wind speed.
anthracite: A hard, black coal that burns with little smoke.
aquaculture: The formal cultivation of fish or other aquatic life forms.
atomic number: The number of protons in the nucleus of an
atomic weight:

The combined number of an atom’s protons and

attenuator: A device that reduces the strength of an energy wave,
such as sunlight.

balneology: The science of bathing in hot water.
barrel: A common unit of measurement of crude oil, equivalent
to 42 U.S. gallons; barrels of oil per day, or BOPD, is a standard
measurement of how much crude oil a well produces.

Alternative Energy


biodiesel: Diesel fuel made from vegetable oil.
bioenergy: Energy produced through the combustion of organic
materials that are constantly being created, such as plants.
biofuel: A fuel made from organic materials that are constantly
being created.
biomass: Organic materials that are constantly being created,
such as plants.
bitumen: A black, viscous (oily) hydrocarbon substance left over
from petroleum refining, often used to pave roads.
bituminous coal: Mid-grade coal that burns with a relatively high
flame and smoke.
brine: Water that is very salty, such as the water found in the ocean.
British thermal unit (Btu or BTU): A measure of heat energy,
equivalent to the amount of energy it takes to raise the temperature of one pound of water by one degree Fahrenheit.
butyl rubber: A synthetic rubber that does not easily tear. It is
often used in hoses and inner tubes.

carbon sequestration: Storing the carbon emissions produced by
coal-burning power plants so that pollutants are not released in
the atmosphere.
catalyst: A substance that speeds up a chemical reaction or
allows it to occur under different conditions than otherwise
cauldron: A large metal pot.
CFC (chlorofluorocarbon): A chemical compound used as a
refrigerant and propellant before being banned for fear it was
destroying the ozone layer.
Clean Air Act: A U.S. law intended to reduce and control air
pollution by setting emissions limits for utilities.
climate-responsive building: A building, or the process of constructing a building, using materials and techniques that take advantage of natural conditions to heat, cool, and light the building.
coal: A solid hydrocarbon found in the ground and formed from
plant matter compressed for millions of years.
coke: A solid organic fuel made by burning off the volatile components of coal in the absence of air.
Alternative Energy



cold fusion: Nuclear fusion that occurs without high heat; also
referred to as low energy nuclear reactions.
combustion: Burning.
compact fluorescent bulb: A lightbulb that saves energy as conventional fluorescent bulbs do, but that can be used in fixtures
that normally take incandescent lightbulbs.
compressed: To make more dense so that a substance takes up
less space.
conductive: A material that can transmit electrical energy.
convection: The circulation movement of a substance resulting
from areas of different temperatures and/or densities.
core: The center of the Earth.
coriolis force: The movement of air currents to the right or left
caused by Earth’s rotation.
corrugated steel:

Steel pieces that have parallel ridges and

critical mass: An amount of fissile material needed to produce an
ongoing nuclear chain reaction.
criticality: The point at which a nuclear fission reaction is in
controlled balance.
crude oil:

The unrefined petroleum removed from an oil well.

crust: The outermost layer of the Earth.
curie: A unit of measurement that measures an amount of radiation.
current: The flow of electricity.

decay: The breakdown of a radioactive substance over time as its
atoms spontaneously give off neutrons.
deciduous trees: Trees that shed their leaves in the fall and grow
them in the spring. Such trees include maples and oaks.
decommission: To take a nuclear power plant out of operation.
dependent: To be reliant on something.
distillation: A process of separating or purifying a liquid by
boiling the substance and then condensing the product.
distiller’s grain: Grain left over from the process of distilling ethanol, which can be used as inexpensive high-protein animal feed.

Alternative Energy


drag: The slowing force of the wind as it strikes an object.
drag coefficient: A measurement of the drag produced when an
object such as a car pushes its way through the air.

E85: A blend of 15 percent ethanol and 85 percent gasoline.
efficient: To get a task done without much waste.
electrolysis: A method of producing chemical energy by passing
an electric current through a type of liquid.
electromagnetism: Magnetism developed by a current of electricity.
electron: A negatively charged particle that revolves around the
nucleus in an atom.
embargo: Preventing the trade of a certain type of commodity.
emission: The release of substances into the atmosphere. These
substances can be gases or particles.
emulsion: A liquid that contains many small droplets of a substance that cannot dissolve in the liquid, such as oil and water
shaken together.
enrichment: The process of increasing the purity of a radioactive
element such as uranium to make it suitable as nuclear fuel.
ethanol: An alcohol made from plant materials such as corn or
sugar cane that can be used as fuel.

Scientific tests, sometimes of a new idea.

feasible: To be possible; able to be accomplished or brought
feedstock: A substance used as a raw material in the creation of
another substance.
field: An area that contains many underground reservoirs of
petroleum or natural gas.
fissile: Term used to describe any radioactive material that can
be used as fuel because its atoms can be split.
fission: Splitting of an atom.
flexible fuel vehicle (FFV): A vehicle that can run on a variety of
fuel types without modification of the engine.
Alternative Energy



flow: The volume of water in a river or stream, usually expressed as
gallons or cubic meters per unit of time, such as a minute or second.
fluorescent lightbulb: A lightbulb that produces light not with
intense heat but by exciting the atoms in a phosphor coating
inside the bulb.
fossil fuel: An organic fuel made through the compression and
heating of plant matter over millions of years, such as coal,
petroleum, and natural gas.
fusion: The process by which the nuclei of light atoms join,
releasing energy.

gas: An air-like substance that expands to fill whatever container
holds it, including natural gas and other gases commonly found
with liquid petroleum.
gasification: A process of converting the energy from a solid,
such as coal, into gas.
gasohol: A blend of gasoline and ethanol.
gasoline: Refined liquid petroleum most commonly used as fuel
in internal combustion engines.
geothermal: Describing energy that is found in the hot spots
under the Earth; describing energy that is made from heat.
geothermal reservoir:
Earth’s mantle.

A pocket of hot water contained within the

global warming: A phenomenon in which the average temperature of the Earth rises, melting icecaps, raising sea levels, and
causing other environmental problems.
gradient: A gradual change in something over a specific distance.
green building: Any building constructed with materials that
require less energy to produce and that save energy during the
building’s operation.
greenhouse effect: A phenomenon in which gases in the Earth’s
atmosphere prevent the sun’s radiation from being reflected
back into space, raising the surface temperature of the Earth.
greenhouse gas: A gas, such as carbon dioxide or methane, that
is added to the Earth’s atmosphere by human actions. These
gases trap heat and contribute to global warming.


Alternative Energy


halogen lamp: An incandescent lightbulb that produces more
light because it produces more heat, but lasts longer because
the filament is enclosed in quartz.
Heisenberg uncertainty principle: The principle that it is impossible to know simultaneously both the location and momentum
of a subatomic particle.
heliostat: A mirror that reflects the sun in a constant direction.
hybrid vehicle: Any vehicle that is powered in a combination of
two ways; usually refers to vehicles powered by an internal
combustion engine and an electric motor.
hybridized: The bringing together of two different types of technology.
hydraulic energy: The kinetic energy contained in water.
hydrocarbon: A substance composed of the elements hydrogen
and carbon, such as coal, petroleum, and natural gas.
hydroelectric: Describing electric energy made by the movement
of water.
hydropower: Any form of power derived from water.

implement: To put something into practice.
incandescent lightbulb: A conventional lightbulb that produces
light by heating a filament to high temperatures.
infrastructure: The framework that is necessary to the functioning of a structure; for example, roads and power lines form part
of the infrastructure of a city.
inlet: An opening through which liquid enters a device, or place.
internal combustion engine: The type of engine in which the
burning that generates power takes place inside the engine.
isotope: A ‘‘species’’ of an element whose nucleus contains more
neutrons than other species of the same element.

kilowatt-hour: One kilowatt of electricity consumed over a onehour period.
kinetic energy: The energy associated with movement, such as
water that is in motion.
Alternative Energy



Kyoto Protocol: An international agreement among many
nations setting limits on emissions of greenhouse gases;
intended to slow or prevent global warming.

lava: Molten rock contained within the Earth that emerges from
cracks in the Earth’s crust, such as volcanoes.
lift: The aerodynamic force that operates perpendicular to the wind,
owing to differences in air pressure on either side of a turbine blade.
lignite: A soft brown coal with visible traces of plant matter in it
that burns with a great deal of smoke and produces less heat
than anthracite or bituminous coal.
liquefaction: The process of turning a gas or solid into a liquid.
LNG (liquefied natural gas): Gas that has been turned into liquid
through the application of pressure and cold.
LPG (liquefied petroleum gas): A gas, mainly propane or butane,
that has been turned into liquid through the use of pressure and cold.
lumen: A measure of the amount of light, defined as the amount
of light produced by one candle.

magma: Liquid rock within the mantle.
magnetic levitation: The process of using the attractive and
repulsive forces of magnetism to move objects such as trains.
mantle: The layer of the Earth between the core and the crust.
mechanical energy: The energy output of tools or machinery.
meltdown: Term used to refer to the possibility that a nuclear
reactor could become so overheated that it would melt into the
earth below.
mica: A type of shiny silica mineral usually found in certain types
of rocks.
modular: An object which can be easily arranged, rearranged,
replaced, or interchanged with similar objects.
mousse: A frothy mixture of oil and seawater in the area where
an oil spill has occurred.

nacelle: The part of a wind turbine that houses the gearbox,
generator, and other components.

Alternative Energy


natural gas: A gaseous hydrocarbon commonly found with petroleum.
negligible: To be so small as to be insignificant.
neutron: A particle with no electrical charge found in the nucleus
of most atoms.
NGL (natural gas liquid): The liquid form of gases commonly
found with natural gas, such as propane, butane, and ethane.
nonrenewable: To be limited in quantity and unable to be replaced.
nucleus: The center of an atom, containing protons and in the
case of most elements, neutrons.

ocean thermal energy conversion (OTEC): The process of converting the heat contained in the oceans’ water into electrical energy.
octane rating: The measure of how much a fuel can be compressed before it spontaneously ignites.
off-peak: Describing period of time when energy is being delivered at well below the maximum amount of demand, often
oil: Liquid petroleum; a substance refined from petroleum used
as a lubricant.
organic: Related to or derived from living matter, such as plants
or animals; composed mainly of carbon atoms.
overburden: The dirt and rocks covering a deposit of coal or
other fossil fuel.
oxygenate: A substance that increases the oxygen level in
another substance.
ozone: A molecule consisting of three atoms of oxygen, naturally
produced in the Earth’s atmosphere; ozone is toxic to humans.

parabolic: Shaped like a parabola, which is a certain type of
paraffin: A kind of alkane hydrocarbon that exists as a white,
waxy solid at room temperature and can be used as fuel or as a
wax for purposes such as sealing jars or making candles.
passive: A device that takes advantage of the sun’s heat but does
not use an additional source of energy.
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peat: A brown substance composed of compressed plant matter
and found in boggy areas; peat can be used as fuel itself, or turns
into coal if compressed for long enough.
perpetual motion: The power of a machine to run indefinitely
without any energy input.
petrochemicals: Chemical compounds that form in rocks, such
as petroleum and coal.
petrodiesel: Diesel fuel made from petroleum.
petroleum: Liquid hydrocarbon found underground that can be
refined into gasoline, diesel fuel, oils, kerosene, and other products.
pile: A mass of radioactive material in a nuclear reactor.
plutonium: A highly toxic element that can be used as fuel in
nuclear reactors.
polymer: A compound, either synthetic or natural, that is made
of many large molecules. These molecules are made from smaller, identical molecules that are chemically bonded.
pristine: Not changed by human hands; in its original condition.
productivity: The output of labor per amount of work.
proponent: Someone who supports an idea or cause.
proton: A positively charged particle found in the nucleus of an

radioactive: Term used to describe any substance that decays
over time by giving off subatomic particles such as neutrons.
RFG (reformulated gasoline): Gasoline that has an oxygenate or
other additive added to it to decrease emissions and improve
rem: An abbreviation for ‘‘roentgen equivalent man,’’ referring to
a dose of radiation that will cause the same biological effect (on
a ‘‘man’’) as one roentgen of X-rays or gamma rays.
reservoir: A geologic formation that can contain liquid petroleum and natural gas.
reservoir rock: Porous rock, such as limestone or sandstone, that
can hold accumulations of petroleum or natural gas.
retrofit: To change something, like a home, after it is built.

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rotor: The hub to which the blades of a wind turbine are connected; sometimes used to refer to the rotor itself and the blades
as a single unit.

scupper: An opening that allows a liquid to drain.
seam: A deposit of coal in the ground.
sedimentary rock: A rock formed through years of minerals
accumulating and being compressed.
seismology: The study of movement within the earth, such as
earthquakes and the eruption of volcanoes.
sick building syndrome: The tendency of buildings that are
poorly ventilated, lighted, and humidified, and that are made
with certain synthetic materials to cause the occupants to feel ill.
smog: Air pollution composed of particles mixed with smoke,
fog, or haze in the air.
stall: The loss of lift that occurs when a wing presents too steep
an angle to the wind and low pressure along the upper surface of
the wing decreases.
strip mining: A form of mining that involves removing earth and
rocks by bulldozer to retrieve the minerals beneath them.
stored energy: The energy contained in water that is stored in a
tank or held back behind a dam in a reservoir.
subsidence: The collapse of earth above an empty mine, resulting
in a damaged landscape.
surcharge: An additional charge over and above the original cost.
superconductivity: The disappearance of electrical resistance in
a substance such as some metals at very low temperatures.

thermal energy: Any form of energy in the form of heat; used in
reference to heat in the oceans’ waters.
thermal gradient: The differences in temperature between different layers of the oceans.
thermal mass: The measure of the amount of heat a substance
can hold.
thermodynamics: The branch of physics that deals with the
mechanical actions or relations of heat.
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tokamak: An acronym for the Russian-built toroidal magnetic
chamber, a device for containing a fusion reaction.
transitioning: Changing from one position or state to another.
transparent: So clear that light can pass through without distortion.
trap: A reservoir or area within Earth’s crust made of nonporous
rock that can contain liquids or gases, such as water, petroleum,
and natural gas.
trawler: A large commercial fishing boat.
Trombé wall: An exterior wall that conserves energy by trapping
heat between glazing and a thermal mass, then venting it into
the living area.
turbine: A device that spins to produce electricity.

uranium: A heavy element that is the chief source of fuel for
nuclear reactors.

viable: To be possible; to be able to grow or develop.
voltage: Electric potential that is measured in volts.

wind farm: A group of wind turbines that provide electricity for
commercial uses.
work: The conversion of one form of energy into another, such
as the conversion of the kinetic energy of water into mechanical
energy used to perform a task.

zero point energy: The energy contained in electromagnetic fluctuations that remains in a vacuum, even when the temperature
has been reduced to very low levels.


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In the technological world of the twenty-first century, few people can truly imagine the challenges faced by prehistoric people as
they tried to cope with their natural environment. Thousands of
years ago life was a daily struggle to find, store, and cook food, stay
warm and clothed, and generally survive to an ‘‘old age’’ equal to
that of most of today’s college students. A common image of
prehistoric life is that of dirty and ill-clad people huddled around
a smoky campfire outside a cave in an ongoing effort to stay warm
and dry and to stop the rumbling in their bellies.
The ‘‘caves’’ of the twenty-first century are a little cozier. The
typical person, at least in more developed countries, wakes up each
morning in a reasonably comfortable house because the gas, propane, or electric heating system (or electric air-conditioner) has
operated automatically overnight. A warm shower awaits because
of hot water heaters powered by electricity or natural gas, and hair
dries quickly (and stylishly) under an electric hair dryer. An
electric iron takes the wrinkles out of the clean shirt that sat
overnight in the electric clothes dryer. Milk for a morning bowl
of cereal remains fresh in an electric refrigerator, and it costs
pennies per bowl thanks to electrically powered milking operations on modern dairy farms. The person then goes to the garage
(after turning off all the electric lights in the house), hits the
electric garage door opener, and gets into his or her gasolinepowered car for the drive to work—perhaps in an office building
that consumes power for lighting, heating and air-conditioning,
copiers, coffeemakers, and computers. Later, an electric, propane,
or natural gas stove is used to cook dinner. Later still, an electric
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popcorn popper provides a snack as the person watches an electric
television or reads under the warm glow of electric light bulbs—
after perhaps turning up the heat because the house is a little
Most people take these modern conveniences for granted. Few
people give much thought to them, at least until there is a power
outage or prices rise sharply, as they did for gasoline in the United
States in the summer and fall of 2005. Many scientists, environmentalists, and concerned members of the public, though, believe
that these conveniences have been taken too much for granted.
Some believe that the modern reliance on fossil fuels—fuels such
as natural gas, gasoline, propane, and coal that are processed from
materials mined from the earth—has set the Earth on a collision
course with disaster in the twenty-first century. Their belief is that
the human community is simply burning too much fuel and that
the consequences of doing so will be dire (terrible). Some of their
concerns include the following:

Too much money is spent on fossil fuels. In the United
States, over $1 billion is spent every day to power the
country’s cars and trucks.
• Much of the supply of fossil fuels, particularly petroleum,
comes from areas of the world that may be unstable. The
U.S. fuel supply could be cut off without warning by a
foreign government. Many nations that import all or most
of their petroleum feel as if they are hostages to the nations
that control the world’s petroleum supplies.
• Drilling for oil and mining coal can do damage to the landscape that is impossible to repair.
• Reserves of coals and especially oil are limited, and eventually supplies will run out. In the meantime, the cost of
such fuels will rise dramatically as it becomes more and
more difficult to find and extract them.
• Transporting petroleum in massive tankers at sea heightens
the risk of oil spills, causing damage to the marine and
coastal environments.
Furthermore, to provide heat and electricity, fossil fuels have to
be burned, and this burning gives rise to a host of problems. It
releases pollutants in the form of carbon dioxide and sulfur into
the air, fouling the atmosphere and causing ‘‘brown clouds’’ over
cities. These pollutants can increase health problems such as lung


Alternative Energy


disease. They may also contribute to a phenomenon called ‘‘global
warming.’’ This term refers to the theory that average temperatures
across the globe will increase as ‘‘greenhouse gases’’ such as carbon
dioxide trap the sun’s heat (as a greenhouse does) in the atmosphere and warm it. Global warming, in turn, can melt glaciers and
the polar ice caps, raising sea levels with damaging effects on
coastal cities and small island nations. It may also cause climate
changes, crop failures, and more unpredictable weather patterns.
Some scientists do not believe that global warming even exists
or that its consequences will be catastrophic. Some note that
throughout history, the world’s average temperatures have risen
and fallen. Some do not find the scientific data about temperature,
glacial melting, rising sea levels, and unpredictable weather totally
believable. While the debate continues, scientists struggle to learn
more about the effects of human activity on the environment. At
the same time, governments struggle to maintain a balance
between economic development and its possible effects on the
These problems began to become more serious after the Industrial Revolution of the nineteenth century. Until that time people
depended on other sources of power. Of course, they burned coal
or wood in fireplaces and stoves, but they also relied on the power
of the sun, the wind, and river currents to accomplish much of
their work. The Industrial Revolution changed that. Now, coal was
being burned in vast amounts to power factories and steam engines
as the economies of Europe and North America grew and developed. Later, more efficient electricity became the preferred power
source, but coal still had to be burned to produce electricity in
large power plants. Then in 1886 the first internal combustion
engine was developed and used in an automobile. Within a few
decades there was a demand for gasoline to power these engines.
By 1929 the number of cars in the United States had grown to
twenty-three million, and in the quarter-century between 1904 and
1929, the number of trucks grew from just seven hundred to 3.4

At the same time technological advances improved life in the
home. In 1920, for example, the United States produced a total of
five thousand refrigerators. Just ten years later the number had
grown to one million per year. These and many other industrial
and consumer developments required vast and growing amounts of
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fuel. Compounding the problem in the twenty-first century is that
other nations of the world, such as China and India, have started to
develop more modern industrialized economies powered by fossil
By the end of World War II in 1945, scientists were beginning to
imagine a world powered by fuel that was cheap, clean, and
inexhaustible (unable to be used up). During the war the United
States had unleashed the power of the atom to create the atomic
bomb. Scientists believed that the atom could be used for peaceful
purposes in nuclear power plants. They even envisioned (imagined) a day when homes could be powered by their own tiny
nuclear power generators. This dream proved to be just that. While
some four hundred nuclear power plants worldwide provide about
16 percent of the world’s electricity, building such plants is an
enormously expensive technical feat. Moreover, nuclear power
plants produce spent fuel that is dangerous and not easily disposed
of. The public fears that an accident at such a plant could release
deadly radiation that would have disastrous effects on the surrounding area. Nuclear power has strong defenders, but it is not
cheap, and safety concerns sometimes make it unpopular.
The dream of a fuel source that is safe, plentiful, clean, and
inexpensive, however, lives on. The awareness of the need for such
alternative fuel sources became greater in the 1970s, when the oilexporting countries of the Middle East stopped shipments of oil to
the United States and its allies. This situation (an embargo) caused
fuel shortages and rapidly rising prices at the gas pump. In the
decades that followed, gasoline again became plentiful and relatively inexpensive, but the oil embargo served as a wakeup call for
many people. In addition, during these years people worldwide
grew concerned about pollution, industrialization, and damage to
the environment. Accordingly, efforts were intensified to find and
develop alternative sources of energy.
Some of these alternative fuel sources are by no means new. For
centuries people have harnessed the power of running water for a
variety of needs, particularly for agriculture (farming). Water
wheels were constructed in the Middle East, Greece, and China
thousands of years ago, and they were common fixtures on the
farms of Europe by the Middle Ages. In the early twenty-first
century hydroelectric dams, which generate electricity from the
power of rivers, provide about 9 percent of the electricity in the

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United States. Worldwide, there are about 40,000 such dams. In
some countries, such as Norway, hydroelectric dams provide virtually 100 percent of the nation’s electrical needs. Scientists,
though, express concerns about the impact such dams have on
the natural environment.
Water can provide power in other ways. Scientists have been
attempting to harness the enormous power contained in ocean
waves, tides, and currents. Furthermore, they note that the oceans
absorb enormous amounts of energy from the sun, and they hope
someday to be able to tap into that energy for human needs.
Technical problems continue to occur. It remains likely that ocean
power will serve only to supplement (add to) existing power
sources in the near future.
Another source of energy that is not new is solar power. For
centuries, people have used the heat of the sun to warm houses,
dry laundry, and preserve food. In the twenty-first century such
‘‘passive’’ uses of the sun’s rays have been supplemented with
photovoltaic devices that convert the energy of the sun into electricity. Solar power, though, is limited geographically to regions of
the Earth where sunshine is plentiful.
Another old source of heat is geothermal power, referring to the
heat that seeps out of the earth in places such as hot springs. In the
past this heat was used directly, but in the modern world it is also
used indirectly to produce electricity. In 1999 over 8,000 megawatts (that is, 8,000 million watts) of electricity were produced by
about 250 geothermal power plants in twenty-two countries
around the world. That same year the United States produced
nearly 3,000 megawatts of geothermal electricity, more than twice
the amount of power generated by wind and solar power. Geothermal power, though, is restricted by the limited number of suitable
sites for tapping it.
Finally, wind power is getting a closer look. For centuries
people have harnessed the power of the wind to turn windmills,
using the energy to accomplish work. In the United States, windoperated turbines produce just 0.4 percent of the nation’s energy
needs. However, wind experts believe that a realistic goal is for
wind to supply 20 percent of the nation’s electricity requirements
by 2020. Worldwide, wind supplies enough power for about nine
million homes. Its future development, though, is hampered by
limitations on the number of sites with enough wind and by
concerns about large numbers of unsightly wind turbines marring
the landscape.
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While some forms of modern alternative energy sources are
really developments of long-existing technologies, others are genuinely new, though scientists have been exploring even some of
these for up to hundreds of years. One, called bioenergy, refers to
the burning of biological materials that otherwise might have just
been thrown away or never grown in the first place. These include
animal waste, garbage, straw, wood by-products, charcoal, dried
plants, nutshells, and the material left over after the processing of
certain foods, such as sugar and orange juice. Bioenergy also
includes methane gas given off by garbage as it decomposes or
rots. Fuels made from vegetable oils can be used to power engines,
such as those in cars and trucks. Biofuels are generally cleaner than
fossil fuels, so they do not pollute as much, and they are renewable. They remain expensive, and amassing significant amounts of
biofuels requires a large commitment of agricultural resources
such as farmland.

Nothing is sophisticated about burning garbage. A more sophisticated modern alternative is hydrogen, the most abundant element
in the universe. Hydrogen in its pure form is extremely flammable.
The problem with using hydrogen as a fuel is separating hydrogen
molecules from the other elements to which it readily bonds, such
as oxygen (hydrogen and oxygen combine to form water). Hydrogen can be used in fuel cells, where water is broken down into its
elements. The hydrogen becomes fuel, while the ‘‘waste product’’ is
oxygen. Many scientists regard hydrogen fuel cells as the ‘‘fuel of
the future,’’ believing that it will provide clean, safe, renewable fuel
to power homes, office buildings, and even cars and trucks. However, fuel cells are expensive. As of 2002 a fuel cell could cost
anywhere from $500 to $2,500 per kilowatt produced. Engines
that burn gasoline cost only about $30 to $35 for the same amount
of energy.
All of these power sources have high costs, both for the fuel and
for the technology needed to use it. The real dreamers among
energy researchers are those who envision a future powered by a
fuel that is not only clean, safe, and renewable but essentially free.
Many scientists believe that such fuel alternatives are impossible, at
least for the foreseeable future. Others, though, work in laboratories around the world to harness more theoretical sources of
energy. Some of their work has a ‘‘science fiction’’ quality, but
these scientists point out that a few hundred years ago the airplane
was science fiction.

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One of these energy sources is magnetism, already used to
power magnetic levitation (‘‘maglev’’) trains in Japan and Germany.
Another is perpetual motion, the movement of a machine that
produces energy without requiring energy to be put into the
system. Most scientists, though, dismiss perpetual motion as a
violation of the laws of physics. Other scientists are investigating
so-called zero-point energy, or the energy that surrounds all matter
and can even be found in the vacuum of space. But perhaps the
most sought-after source of energy for investigators is cold fusion,
a nuclear reaction using ‘‘heavy hydrogen,’’ an abundant element in
seawater, as fuel. With cold fusion, power could be produced
literally from a bucket of water. So far, no one has been able to
produce it, though some scientists claim to have come very close.
None of these energy sources is a complete cure for the world’s
energy woes. Most will continue to serve as supplements to conventional fossil fuel burning for decades to come. But with the
commitment of research dollars, it is possible that future generations will be able to generate all their power needs in ways that
scientists have not even yet imagined. The first step begins with
understanding fossil fuels, the energy they provide, the problems
they cause, and what it may take to replace them.

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Fossil Fuels
Nearly 90 percent of the world’s energy comes from fossil fuels.
Because fossil fuels are the main source, they are not alternative
energy sources. Fossil fuels include coal, natural gas, and petroleum (puh-TROH-lee-uhm), which is often called oil. People use
fossil fuels to meet nearly all of their energy needs, such as powering cars, producing electricity for light and heat, and running
factories. Because their use is so widespread, it is important to
understand fossil fuels in order to make informed decisions about
present and future alternative energy sources.

Fossil fuels are a popular source of energy because they are
considered convenient, effective, plentiful, and inexpensive, but a
few nations have most of the world’s fossil fuels, a fact that often
causes conflicts. Nevertheless, as of 2006, there are no practical
and available alternatives to fossil fuels for most energy needs, so
they continue to be heavily used.
Types of fossil fuels

Fossil fuels are substances that formed underground millions of years
ago from prehistoric plants and other living things that were buried
under layers of sediment, which included dirt, sand, and dead plants. To
turn into fossil fuels, this organic matter (matter that comes from a life
form and is composed mainly of the element carbon) was crushed,
heated, and deprived of oxygen. Under the right conditions and over
millions of years, this treatment turns dead plants into fossil fuels.
The three main types of fossil fuels correspond to the three
states of matter—solid, liquid, and gas:
• Coal is a solid.
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Words to Know
Alkane A kind of hydrocarbon in which the
molecules have the maximum possible number of hydrogen atoms and no double bonds.
Barrel A common unit of measurement
of crude oil, equivalent to 42 U.S. gallons;
barrels of oil per day, or BOPD, is a standard measurement of how much crude oil
a well produces.

rises, melting icecaps, raising sea
levels, and causing other environmental

Catalyst A substance that speeds up a
chemical reaction or allows it to occur under
different conditions than otherwise possible.
Clean Air Act A U.S. law intended to
reduce and control air pollution by setting
emissions limits for utilities.
Emissions The by-products of fossil fuel
burning that are released into the air.
Global warming A phenomenon in which
the average temperature of the Earth

Octane rating The measure of how much
a fuel can be compressed before it spontaneously ignites.


Greenhouse effect A phenomenon in
which gases in the Earth’s atmosphere
prevent the sun’s radiation from being
reflected back into space, raising the surface temperature of the Earth.

Ozone A molecule consisting of three
atoms of oxygen, naturally produced in
the Earth’s atmosphere; ozone is toxic to
Seismology The study of movement
within the earth, such as earthquakes
and the eruption of volcanoes.

Petroleum is a liquid.
Natural gas is a gas.

Several fossil fuels are made by refining petroleum or natural
gas. These fuels include gases such as propane, butane, and
Natural Gas Versus Gasoline

Natural gas is not sold at gas stations. The fuel used in cars is
liquid petroleum, or gasoline. Although most people call it ‘‘gas,’’
this fuel is not the same thing as natural gas. The word gas refers to
natural gas, not gasoline. The word oil refers to petroleum.
Whether a fossil fuel formed as a solid, liquid, or gas depends on
the location, the composition of the materials, the length of time
the matter was compressed, how hot it became, and how long it
was buried. Coal formed from accumulated layers of plants that
died in swamps and were buried for millions of years. Petroleum
and natural gas formed from microscopic plants and bacteria in the
oceans. Both petroleum and natural gas formed in places that
could contain them: pockets, or reservoirs (reh-zuh-VWARS), in
the undersea rock.

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Dinosaurs in the Gas Tank
It is unlikely that fossil fuels are made of dinosaurs. Most
fossil fuels formed about 300 million years ago, and most of
them are made mainly of plant matter. Dinosaurs did not
appear until about 230 million years ago, so the first dinosaur
was not born until the youngest petroleum had already
formed. Dinosaur fossils, however, do have something in
common with fossil fuels. Fossils, whether they are dinosaurs
or coal, are the hardened remains of animals and plants
preserved in Earth’s crust from an earlier age. Dinosaur fossils formed when dinosaurs were buried in sand or dirt, and
their skeletons were hardened by minerals that seeped in
through tiny holes in the bone.

Earth has a lot of fossil fuels. Scientists in 2005 estimated that
the ground contains about ten trillion metric tons of coal, enough
to fuel human energy needs for hundreds of years. Petroleum and
natural gas deposits are not nearly so extensive. Most scientists
believe that if people keep using up oil and gas at 2005 rates, all
known petroleum and gas reserves will be used up by the beginning of the twenty-second century.
At the end of the twentieth century, petroleum supplied about 40
percent of the energy needs of the United States. Another 22 percent
was covered by coal and 24 percent by natural gas. The International
Energy Agency (IEA) has predicted that the world will need almost
60 percent more energy in 2030 than it did in 2002. The IEA believes
that fossil fuels will still be supplying most of those needs by 2030.
Other kinds of fossil fuels exist, but none of them can be
extracted, recovered, or used efficiently. These fossil fuels include:
• Gas hydrates, which are deposits of methane and water that
form crystals in ocean sediments. There is currently no
technology for extracting methane from the crystals, so gas
hydrates are not yet considered a part of world energy
• Tar sands, which are patches of tar in sandstone. Petroleum
sometimes gets embedded in sandstone, and the bacteria in
the sandstone and the surrounding water make the
petroleum turn into tar. Tar sands are difficult to recover
and use.
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Oil shale, which is a kind of rock full of a waxy organic
substance called kerogen (KEHR-uh-juhn). Kerogen
formed from the same microscopic plants and bacteria that
make up petroleum, but it never reached the pressure or
temperature that would have turned it into oil. It is not
currently practical to recover or use oil shale.

How fossil fuels work

Fossil fuels generate energy by burning. This energy can serve a
variety of purposes from heating homes to powering automobiles.
The simplest devices that use fossil fuels burn them so that people
can take advantage of the heat. For example, some homes are
heated by furnaces that burn natural gas. The heat from the burning gas warms the house. Camping stoves often burn propane that
is fed to the stove burners from an attached bottle. Coal stoves
burn lumps of coal.
Most fossil fuel-powered operations, however, use the burning
of the fossil fuel to power much more complex machines, such as
internal combustion engines. In many cases, other fuels could
supply the necessary heat; for example, locomotives could be
powered by burning wood instead of burning coal, and power
plants can be powered by water instead of coal. The advantage of
fossil fuels in these situations is that they produce large amounts of
heat for their volume, and they are currently widely available, with
some liquid and gas fuels available at pumps.
The internal combustion engine

Automobiles use fossil fuel (gasoline) to power their internal
combustion engines. An internal combustion engine burns a fuel
to power pistons, which make the engine turn. Internal combustion engines have been around since the 1860s. The four-stroke
‘‘Otto’’ engine was invented in 1867 by Nikolaus August Otto
(1832–1891), a German engineer. Another German engineer,
Rudolph Diesel (1858–1913), invented the diesel engine in 1892.
The basic principles of internal combustion have not changed
since then.
An engine contains several cylinders (most cars have between
four and eight) that make the engine move. A four-stroke cylinder
works like this:


The intake valve opens to let air and fuel into the
cylinder while the piston is down. This is called the
intake stroke.

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The piston begins traveling back up. The intake valve closes
and the piston compresses the air and fuel in the cylinder.
This is called the compression stroke.
The spark plug creates a spark, which ignites the fuel and
air so that it explodes. The explosion pushes the piston
down. The piston rotates the crankshaft, which turns the
engine. This is called the power stroke.
The exhaust valve opens. The piston moves back up,
forcing the burned gases out through the exhaust valve.
The piston travels back down, the exhaust valve opens,
and the intake stroke begins again. This is called the
exhaust stroke.

Photo of the original 1891
gasoline-engined Daimler
automobile. In 1885, Karl
Benz and Gottlieb Daimler
developed an internal
combustion engine, building
the first motorcycle and cars
using gasoline. ª AP Images.

One complete cycle of a four-stroke engine will turn the crankshaft twice. A car engine’s cylinders can fire hundreds of times in a
minute, turning the crankshaft, which transmits its energy into
turning the car’s wheels. The more air and fuel that can get into a
cylinder, the more powerful the engine will be.
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What does Octane Mean?
Gasoline comes in several varieties labeled with words such as
‘‘regular’’ or ‘‘supreme,’’ each with a number. The higher the
number on the gasoline, the more expensive it is. That number is
the gasoline’s octane rating, which tells how much the fuel can
be compressed before it will spontaneously ignite. In a car
engine, gasoline is supposed to ignite in one of the engine’s
cylinders when it is lit by a spark plug; it is not supposed to ignite
on its own. When it ignites on its own, the engine ‘‘knocks.’’ This
can damage the engine. High-performance cars, though,
increase their horsepower by increasing the amount of compression in the engine, which makes knocking more likely. That
is why high-performance cars have to use expensive, high octane

Most engines that run on gasoline can also be powered with
natural gas or LPGs (liquefied petroleum gas), with some minor
modifications to the fuel delivery system. The basic method of
combustion is the same.
A diesel engine is similar to a gasoline engine except that only air
enters the cylinder during the intake stroke, and only air is compressed during the compression stroke. The fuel is sprayed into the
cylinder at the end of the compression stroke, when the air temperature is high enough to cause it to ignite spontaneously without a
spark. Diesel engines are usually heavier and more powerful than
gasoline engines and have better fuel efficiency; they are used in
buses, trucks, ships, and some automobiles. In Europe, a large
proportion of personal automobiles are powered by diesel fuel, but
diesel fuel is less common in the United States because of clean-air
laws. Diesel fuel has more exhaust emissions than gasoline.
Coal-burning engines

Using coal for heat and cooking can be as straightforward as
putting coal in a stove and setting it on fire; the coal burns slowly
and emits steady heat. But the way coal really had an effect on
people’s lives was through its use as a fuel for engines, such as steam
engines that powered locomotives that pulled trains. Coal-burning
locomotives used steam to power their wheels. A locomotive works
like this:

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Side view of George
Stephenson’s Rocket
locomotive. The train was
designed and built in 1829
and is considered the
forerunner of all other steam
locomotives. ª HultonDeutsch Collection/Corbis.




In order to keep the fire burning, the locomotive has
to carry a large pile of coal, which a person called the
fireman constantly shovels into the firebed. (More modern
locomotives have mechanical shovels to feed the fires.)
The ashes left over from the burning coal fall through grates
into an ashpan below the firebed. The ashes are dumped
at the end of the train’s run.
This basic process was not only used in trains. Steam
engines also powered riverboats, steamships, and factories.

Most trains in the twenty-first century are powered by diesel
fuel or electricity. China still uses coal-burning trains for normal
transportation, but in Europe and the United States steam locomotives are only used as part of museum displays to entertain tourists.
Where electricity comes from

Fossil fuels are important for the production of electricity. Most
power plants have generators that spin to create electricity, which
is then sent out through the wires and poles that distribute it to
consumers. Something has to power those generators. The vast
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majority of power plants burn fossil fuels for this purpose. (The
rest use nuclear power or hydroelectric power.)
About one-half of the electricity in the United States comes from
coal-burning power plants. These plants store their coal in giant
outdoor piles. People driving bulldozers push the coal onto conveyor belts that carry it up to silos or bunkers. The coal is typically
crushed so it can be fed into most power station furnaces. Then it
is fed into giant burners that burn night and day to create steam to
turn the generator. Most plants need constant deliveries of coal to
have enough fuel to keep the burners running at all times. They
produce large amounts of ash. One of the jobs of plant operators is
to keep the ash from clogging up the works.
Natural gas is the other significant fossil fuel source of electrical
power in the United States, supplying about one-fifth of the
nation’s electricity. Natural gas plants use turbines to spin generators. The turbines are connected to pipelines that provide a constant supply of natural gas. Some plants use the natural gas to
power the generator directly. Others use the natural gas to create
steam, which spins the generator.
The United States government encourages power companies to
build plants powered by natural gas because natural gas burns
much more cleanly than coal and therefore does not create as
much pollution. The U.S. Department of Energy predicts that 90
percent of new power plants built in the early 2000s will be
powered by natural gas.
Historical overview: Notable discoveries and the people
who made them

Humans have been using fossil fuels for thousands of years,
possibly as long ago as twenty thousand years. Oil sometimes seeps
up through the ground, so it was easy for people to see it and
experiment with it. The ancient Mesopotamians in what is now Iraq
may have discovered a way to use oil about five thousand years ago.
Historians believe that people first used petroleum as oil for lighting,
dipping wood in it and setting it on fire as a torch. Ancient Greeks
and Romans used coal as a fuel for heat and cooking. Ancient
temples sometimes had eternal flames, which may have been
powered by natural gas leaking up from the ground.
In the British Isles coal began to be used in the late thirteenth
century, and it was the dominant fuel in London by 1600. Wood
was abundant, so coal took time to become widely adopted. The first
widespread use of fossil fuels occurred in the late 1700s, with the

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development of the steam engine and the start of the industrial revolution. James Watt (1736–1819) is usually credited as the inventor of the
first commercially efficient steam engine in 1769, though his work was
based on the inventions of others, particularly that of the Cornish
engineer Thomas Newcomen (1664–1729), whose atmospheric steam
engine was completed in 1711. The steam engine, powered by coal,
made the industrial revolution possible. Steam engines could power
trains, boats, and factories. The first coal-burning steam locomotive
was built in Wales in 1804. In 1825 coal-powered trains became
available for commercial use. Robert Fulton (1765–1815) invented
the steam-powered riverboat in 1807, and riverboats became a popular
way to travel up and down the Mississippi River in the United States. In
1819 a steamship crossed the Atlantic Ocean for the first time. By the
mid-1800s people were regularly traveling between Europe and the
United States on coal-powered steamships.
People began using natural gas to power lamps in 1785 in
England. Natural gas lamps became common in the United States
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Illustration of the Savannah,
the first steamship to cross
the Atlantic Ocean.
ª Bettman/Corbis.



around 1816. The first natural gas well was built in Fredonia, New
York, in 1821.
In the 1850s an American lawyer named George Bissell
(1821–1884) investigated the possibility of using oil as lamp fuel.
He thought he could find more oil if he drilled into the ground, so
he hired Edwin Drake (1819–1880) to drill the first oil well. This
well was completed in Titusville, Pennsylvania, in 1859. Drake
used the oil to make kerosene, which people used in lamps and
heaters. Gasoline was a by-product (one of the leftovers) of the
process of making kerosene, but no one at the time had a real use
for it. Other people began looking for oil, and they found it in
places such as Indonesia, Texas, and the Middle East.
By the end of the nineteenth century many people were using
light bulbs instead of kerosene lamps, so oil producers began
adapting their product for other uses. The first gasoline-powered
internal combustion engine was developed in 1886. The first massproduced gasoline-powered car was the Oldsmobile, introduced in
1902. Henry Ford (1863–1947) introduced the Model T in 1908
and began producing his inexpensive cars on an assembly line. By
1920 there were twenty-three million cars in the world, and it
turned out that gasoline was the most practical way to power them.
The Wright brothers, Orville (1871–1948) and Wilbur (1867–1912),
flew their first successful airplane in 1903. They used petroleum
as their fuel, and from that point on airplanes were powered by
petroleum-based fuels. Diesel fuel gradually replaced coal as the
dominant fuel for large ships. Diesel locomotives appeared around
1920 and had replaced steam engines by 1960.
Consumption of all fossil fuels increased greatly during the twentieth century. Petroleum was used to power automobiles, airplanes,
ships, and electric plants. Coal heated homes, powered factories and
trains, and generated electricity at power plants. Toward the end of
the twentieth century the oil industry began to develop the potential
of natural gas, and this fuel became useful in homes and businesses
as well as in industry. Minor fossil fuels such as kerosene, propane,
and butane were all widely used at the beginning of the twenty-first
century. Perhaps the most notable transition from the twentieth to
the twenty-first century is from stationary devices burning solid
fuels to mobile sources using liquid fuels.
Current and future technology

Fossil fuels supply a large percentage of the world’s energy
needs through a variety of technologies. Most automobiles and

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other vehicles use gasoline to power internal combustion engines,
in which the burning that generates power takes place inside the
engine. Coal or gasoline is burned to power factory equipment.
Coal-fired plants generate much of the world’s electricity. Almost
every twenty-first century technology uses fossil fuels in some way.
Fossil fuel technology has changed. Scientists are constantly
looking for technology that makes fossil fuels work more efficiently and reduces pollution. Fossil fuels are so common and
considered so necessary that there is great incentive for engineers
to improve methods of acquiring and using fossil fuels. Technology
under development includes:
• Clean coal technology
• Vehicles powered by natural gas or substances other
than gasoline
• Fuel cells that use small amounts of fossil fuel to
make hydrogen
• Safer means of transporting fossil fuels
• Improved techniques for cleaning fossil fuels before,
during, and after burning
• Improvements in extracting fossil fuels from the ground
Benefits and drawbacks of fossil fuels

Most existing technology was designed for use with fossil fuels.
Fossil fuel transport systems are already in place. Pipelines for oil
and natural gas and trucks and ships for petroleum products move
the fossil fuels where they are needed. And consumers can buy the
fossil fuel products they use on practically every corner.
Yet, fossil fuels are non-renewable resources. Current supplies
took a very long time to form under the Earth’s crust. These
supplies will be gone long before the Earth has a chance to replace
them. Even now, getting fossil fuels is a major drawback to using
them. Countries that do not have reserves of oil and natural gas
must depend on those countries that do. And using fossil fuels
contributes to air and water pollution.
Environmental impact of fossil fuels

Fossil fuels cause or contribute to environmental problems such
as the following:
• Damage to the landscape
• Air pollution
• Water pollution
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Oil spills
Radioactivity (Coal contains the radioactive elements uranium
and thorium, and most coal-fired plants emit more radiation
than a nuclear power plant.)
• Health problems for workers and those nearby (Many fossil
fuel byproducts can be harmful to humans: breathing toxic
hydrocarbons, nitrogen oxides, and particulate matter can
cause ailments such as chest pain, coughing, asthma, chronic
bronchitis, decreased lung function, and cancer, and exposure
to mercury can lead to nerve damage, birth defects, learning
disabilities, and even death.)
Some experts believe the environmental problems are so serious
that people need to find alternatives to fossil fuels even before all
reserves are used up. Others believe that technological improvements will allow the use of fossil fuels for many years to come.

Damage to the landscape

Fossil fuels are found underground. There is no way to get them
out without cutting into or removing the dirt on top of deposits.
Strip mining for coal involves removing the dirt and rocks above a
deposit of coal and digging out the coal beneath it. Miners sometimes remove the tops of mountains to remove the coal below.
Mines below the Earth’s surface can collapse, resulting in changes
to the landscape on top of them.
Though drilling for oil and natural gas is not always as destructive as coal mining, it still involves machinery that can destroy
animal habitats and pipelines that cut across the land for thousands of miles.
Air pollution

Air pollution results from driving cars and trucks, from burning
coal and other fossil fuels to create electricity, from industry, from
using gas-powered stoves and appliances, and from many other
daily activities. As the number of drivers increases and average fuel
efficiency declines due to a shift to lower mileage SUVs, air pollution increases. As the number of people using electricity increases,
so does air pollution.
There are several types of air pollution:
• Particulate matter is tiny particles of burnt fossil fuels that
float in the air. This kind of pollution is sometimes called
black carbon pollution. Examples of coarse particulate
matter include the smoke that comes from a diesel-powered

Alternative Energy




truck or the soot that rises from a charcoal-burning grill.
However, in addition to the visible black particulate matter
there is the fine material (less than 2.5 microns) that creates
large health problems.
Smog is a mixture of air pollutants, both gases and particles,
that create a haze near the ground. Sulfate particles, created
when sulfur dioxide combines with other chemicals in the
air, and ozone are the main causes of smog and haze in most
of the United States.
Ozone is a form of oxygen that contains three oxygen atoms
per molecule. (O2, the form of oxygen that humans need to
survive, contains two oxygen atoms per molecule.) It is
common in Earth’s atmosphere, where it blocks much of the
sun’s ultraviolet radiation, preventing it from burning up
most forms of life. Though it is beneficial and necessary in
the atmosphere, ozone is also destructive and highly toxic to
humans. Ozone forms spontaneously from the energy of
sunlight in the air, but it can also form from other reactions,
such as sparks from electrical motors or the use of high
Alternative Energy

Aerial view of mountaintop
removal and reclamation in
the Indian Creek vicinity of
Boone County, West Virginia.
ª Library of Congress.



Where Does Air Pollution Come From?
According to the Environmental Protection Agency (EPA), mobile
sources, such as cars, trucks, buses, trains, airplanes, and
boats, represent the largest contributor to U.S. air toxics. In
1999 as much as 95 percent of the carbon monoxide in typical
U.S. cities came from mobile sources, according to EPA studies.
More than half of all nitrogen oxide air pollution in the United
States came from on road and non-road vehicles. The rest came
from industry, such as power plants and factories. But the EPA
states that the majority of all hydrocarbons (53 percent) and
particulate matter (72 percent) comes from non-mobile sources
such as power plants and factories.





voltage electrical equipment such as televisions. Fossil fuel
pollution contributes nitrogen oxides and other organic
gases that can react to create ozone. Ozone forms close to
the ground on light sunny days, especially in cities.
Sulfur dioxide is a by-product of burning fossil fuels. It is
one of the key ingredients of acid rain. The United States
Environmental Protection Agency (EPA) considers the
reduction of sulfur dioxide emissions a crucial part of the
effort to clean up the nation’s air. The United States has set
national air quality standards, and state and local
governments are required to meet them.
Nitrogen oxides are gases that contain nitrogen and oxygen
in different amounts. Most of them are colorless and
odorless. Almost all nitrogen oxides are created by the
burning of fossil fuels in motor vehicles, power plants, and
industry. Nitrogen oxides react with sulfur dioxide to
produce acid rain. They also contribute to the formation of
ozone near the ground, and they form particulate matter that
clouds vision and toxic chemicals that are dangerous to
humans and animals. In addition, they harm water quality by
overloading water with nutrients. Finally, they are believed
to contribute to global warming.
Carbon monoxide is one of the main sources of indoor air
pollutants. It forms from the burning of fossil fuels in
appliances such as kerosene and gas space heaters, gas water
heaters, gas stoves and fireplaces, leaking chimneys and

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Accidental Death
Burning a charcoal grill or kerosene heater or running a car
engine inside an enclosed space, such as a closed garage,
can produce enough carbon monoxide to kill a person. Every
year people die from inhaling concentrated carbon monoxide.
Death comes easily and without warning because the victim
often does not notice any symptoms; he or she simply gets
sleepy from lack of oxygen, loses consciousness, and dies as
carbon dioxide builds up in the blood.

furnaces, gasoline-powered generators, automobile exhaust
in enclosed garages, and other sources. Carbon monoxide
binds with the iron atoms in hemoglobin (the part of blood
that carries oxygen) and prevents the blood from taking up
enough oxygen to keep the brain running.
The United States and the individual states have passed various
laws regulating air pollution. The Clean Air Act, passed in 1990, is
one of the most important. It requires states to meet air quality
standards, creates committees to handle pollution that crosses
borders between states or from Mexico or Canada, and allows the
EPA to enforce the law by fining polluters. It creates a program
allowing polluting businesses to apply for and buy permits that let
them release a certain amount of pollutants. Businesses can buy,
sell, and trade these permits. They can receive credits if they
release fewer emissions than they are allowed to produce.
One major difficulty with controlling air pollution is that some
pollutants can travel thousands of miles from their sources. Certain types of air pollution in one state can originate from a coalburning plant in another. For that reason, air pollution regulations
must focus on large regions if they are to have any effect at all.
Acid rain

Acid rain is rain with small amounts of acid mixed into it. When
sulfur dioxide and nitrogen oxides are released from burning fossil
fuels, they mix with water and oxygen in the atmosphere and turn
into acids. The acids in acid rain are not strong enough to dissolve
a person, but they can contribute to environmental problems, such
as the following:
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A HEPA Filter?
Particulate matter is air pollution in the form of particles
suspended in the air. Of special concern to human health
are fine particles (of less than 2.5 microns) that are easily
inhaled and can cause irritation to the eyes, nose, and throat,
and may get into the lungs and either be absorbed by the
bloodstream or stay embedded in the lungs to cause more
serious breathing problems. Particulate matter has even been
linked to an increased risk of heart attack in people with heart
disease. Breathing in the particles may cause shortness of
breath and chest tightness. A HEPA (HEP-ah) filter cleans
particulate matter from indoor air when it is used in vacuum
cleaners or air conditioning and heating units. A HEPA filter
makes indoor air healthier because it is a ‘‘high efficiency
particulate arresting’’ filter.



Polluting lakes and streams, which can kill fish, other
animals, and aquatic plants and disrupt entire ecosystems
Damaging trees at high elevations
Deteriorating the stone, brick, metal, and paint used in
everything from buildings and bridges to outdoor artworks
and historical sculptures
Damaging the paint on cars
Impairing visibility by filling the air with tiny particles
Causing health problems in humans when the toxins in
the rainfall go into the fruits, vegetables, and animals that
people eat.

The EPA has an Acid Rain Program that limits the amount of
sulfur dioxide that power plants can produce, and the program has
reduced emissions somewhat. Reducing emissions overall should
contribute to eliminating acid rain.
Global warming

Most scientists believe that the use of fossil fuels has changed the
world’s climate, and that this change is continuing. Burning fossil
fuels releases gases called greenhouse gases, which include carbon
dioxide, methane, and nitrous oxide. Greenhouse gases are good at
trapping heat. When the sun’s radiation hits Earth, some of the heat

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Smog shrouds the skyline of
the city of Los Angeles in a
view from the Hollywood
Hills. The city is famous for
pollution. ª Andrew

is reflected back into space. When greenhouse gases get into the
atmosphere, they act like the walls of a greenhouse, holding the heat
in so that it cannot escape back to space. Ordinarily, this would be a
good thing, because life on Earth depends on keeping some of the
sun’s heat on the surface. Since the industrial revolution, however,
the amount of greenhouse gases in the atmosphere has increased.
The amount of carbon dioxide has increased 30 percent; the amount
of methane has increased 100 percent; and the amount of nitrous
oxide has risen 15 percent. These gases make the atmosphere better
at keeping heat in. As a result, Earth’s temperature has risen and
continues to rise.
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Kyoto Protocol
In 1997 many of the world’s nations agreed to work together to
reduce greenhouse gases and stop global warming. These
nations signed an agreement in Kyoto, Japan, referred to as
the Kyoto Protocol. The Kyoto Protocol sets targets for reducing
emissions and deadlines for nations to meet those targets. The
United States and Australia have not agreed to participate
because the protocol does not place the same requirements
on developing nations as it does on industrialized nations.

The increase in global temperatures can cause many problems.
A possible effect is a rise in sea levels, which can change the shape
of coastlines; cause changes in forests, crops, and water supplies;
and harm the health of humans and animals. Fossil fuels account
for 98 percent of carbon dioxide emissions, 24 percent of methane
emissions, and 18 percent of nitrous oxide emissions.
Oil spills

When transporting petroleum, there is always the danger that
the oil will leak out of its tank and contaminate the local environment. Many oil spills occur when a giant tanker ship crashes and
the petroleum leaks out of the tank into the ocean. Spills can also
happen when oil wells or pipelines break, or when tanker ships
wash their giant tanks, rinsing the residue straight into the ocean.
When oil gets into the ocean, it quickly spreads over the surface
of the water, forming an oil slick. The oil clumps into tar balls and
an oil-water mixture called mousse. Seabirds and marine mammals
get caught in the oil and die.
The 1989 wreck of the Exxon Valdez in Prince William Sound,
Alaska, caused the worst oil spill that has so far occurred in North
America. The ship hit and slid onto a coral reef. The accident
allowed 38,800 tons of oil from the tanker to spread over 1,200
miles (1,930 kilometers) of shoreline, killing over one thousand
sea otters and between 100,000 and 300,000 seabirds. At least 153
bald eagles also died from eating dead seabirds covered with oil.
The cleanup cost nearly $3 billion, a large portion of that furnished
by the United States government.
Almost 14,000 oil spills are reported each year in the United
States. Usually, the owner of the oil or the tanker takes responsi18

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Build a Better Tanker
Transporting oil safely is a big concern for the oil industry.
Modern tankers are much stronger than older ones, and they
are built with double hulls. Double hull means there are two
layers of metal between the oil and the ocean. Double-hulled
tankers are much less likely to be torn open if they run into
rocks or coral reefs.

bility for cleanup. Occasionally, local, state, and federal agencies
must help. The EPA takes care of spills in inland waters, and the
United States Coast Guard responds to spills in coastal waters and
deepwater ports.
The long-term effects of oil spills are not known. Though it
appears that it is possible to clean up most of the oil and that the
local ecosystem can recover, it also seems that some of the effects
of oil are very long-lasting. The Prince William Sound environment still had some problems in the early 2000s: many animal
species affected by the spill had still not recovered to their pre-spill
numbers, and some oil remained on the region’s beaches.
Economic impact of fossil fuels

Because they have been plentiful and are usually less expensive
than other energy sources, fossil fuels supply nearly all of the
world’s energy. At the beginning of the twenty-first century the
world economy is based on inexpensive fossil fuel. Almost all
modes of transportation and industries require fossil fuels. Prices
of consumer goods and services from food to airline tickets are
partly determined by the cost of fuel. When the price of oil goes
up, people who sell goods and services often must raise their prices
because it costs more to make or deliver products.
As developing nations increase their use of automobiles, electricity, and other goods and services, their demands for fossil fuels
increase. For example, oil consumption in China grew rapidly in
the early twenty-first century. By 2003 China was consuming the
second largest amount of oil in the world, behind the United
States. China does not have sufficient fuel reserves to supply its
own needs, so it must buy petroleum from other countries. Oil
producers can raise their prices because they have several buyers
competing to purchase their product.
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Yet fossil fuels are still the cheapest source of power in the
modern world. Alternative energy sources, such as solar power or
hydrogen fuel cells, are much more expensive. Most people will
not choose an expensive source of power when a cheap one is
available, even if the cheap source contributes to pollution. For
example, many coal-burning power plants still produce large
amounts of pollution because the cost of controlling the pollution
is deemed too expensive.
Societal impact of fossil fuels

Modern life would be impossible without fossil fuels, and in
many ways fossil fuels have benefited people. The fact that fossil
fuels are everywhere means that it is nearly impossible to take any
action without using them. In many houses turning on a light uses
fossil fuels. Shopping, eating, going to school, and sleeping in a
heated or air conditioned home require the burning of fossil fuels.
Fossil fuels are an important global issue. Countries have clashed
over the issue of oil.
Air and water pollution are also global issues. The pollutants that
come from fossil fuels can spread from country to country. Developing nations, such as Thailand and China, have been rapidly
increasing the number of cars owned and of fossil fuel-powered
factories and power plants, which has resulted in an increase in air
pollution. International groups that want to protect the environment
must balance air and water quality with the desire of poorer nations
to improve their economies. The less developed countries feel that
the countries of Europe and the United States were allowed to use
fossil fuels to build their economies, regardless of the environmental
consequences, and that they too should be given that opportunity
without being forced to worry about pollution.
Issues, challenges, and obstacles in the use of fossil fuels

Fossil fuels are widely used and widely accepted. Nevertheless,
there are ways to make fossil fuels less polluting, such as the use of
clean coal technology and hybrid automobiles. These technologies
have not yet become widespread, in part because they cost more
than the methods that are currently used. As pollution increases
and fossil fuels become harder to get, new methods of using fossil
fuels will probably become more common.
Petroleum is the most widely used fossil fuel, supplying about
40 percent of the world’s energy. Petroleum is also called oil. One

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Is Petroleum Really a Fossil Fuel?
Some scientists in Russia and Ukraine believe that petroleum
is not actually a fossil fuel but that it formed in Earth’s crust
from rocks and minerals rather than plants and animals.
These scientists believe that the formation of oil requires
higher pressure than the formation of coal and that there is
not enough organic matter in Earth’s deposits to explain the
amount of petroleum available in large fields. Scientists in
other countries disagree with this idea.

of the most important uses of petroleum is as fuel for motor
vehicles. It can also be used to pave roads, to make other chemicals, and to moisturize skin.
Petroleum is a hydrocarbon, which means it is made up mostly
of molecules that contain only carbon and hydrogen atoms. It also
contains some oxygen, nitrogen, sulfur, and metal salts. The term
petroleum encompasses several different kinds of liquid hydrocarbons. The main ones are oil, tar, and natural gas.
Origins of petroleum

The ingredients in petroleum include microscopic plants and
bacteria that lived in the ocean millions of years ago. When they
died, these plants and bacteria fell to the bottom of the ocean and
mixed with the sand and mud there. This process continued for
millions of years, and gradually the layers at the bottom were
crushed by the layers above them. The mud became hotter, and
the pressure and heat slowly transformed it. The minerals turned
into a kind of stone called shale, or mudstone, and the organic
matter turned into petroleum and natural gas.
Because they are not solid, petroleum and natural gas can move
around. They seep into holes in undersea rocks such as limestone
and sandstone, called reservoir rocks. These rocks are porous,
meaning they have tiny holes in them that allow liquids and gases
to pass through, and function as sponges. Because they are lighter
than water, oil and gas migrate upward, although still trapped
within Earth’s crust. Sometimes the oil and gas end up in an area
of rock that is not porous and is shaped in such a way that it can
contain liquid and gas. This area becomes a reservoir, or geologic
trap, that holds the petroleum and natural gas. Rock formations
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especially good at trapping hydrocarbons include anticlines, or
layers of rock that bend downward; salt domes, or anticlines with
a mass of rock salt at the core; and fault traps, or spaces between
cracks in Earth’s crust.
Within a trap, petroleum, natural gas, and water separate into
layers, still within the porous reservoir rocks. Water is the heaviest
and stays on the bottom. Petroleum sits on top of the water, and
natural gas sits on top of the petroleum. Sometimes the natural gas
and petroleum inside a trap find a path to the surface and seep out.
Finding petroleum

Geologists are scientists who study the history of Earth and its life
as recorded in rocks. When looking for oil they want to find underground geologic traps because these traps often contain petroleum
that can be removed by drilling. Geologists use a variety of techniques to find oil traps. They use seismology (syze-MAH-luh-jee),
sending shock waves through the rock and examining the waves
that bounce back. Geologists also study the surface of the land,
examining the shape of the ground and the kinds of rocks and soil
present. These scientists use gravity meters and magnetometers to
find changes in Earth’s gravity or magnetic fields that indicate the
presence of flowing oil. They use electronic ‘‘sniffers’’ to search for
the smell of hydrocarbons. Finding oil is difficult. Scientists searching for oil have only about a ten percent success rate.
Petroleum is present all over the world, but large concentrations
of it exist in only a few places. These accumulations are called
fields, and they are the places where oil companies drill for oil. The
largest fields in the world are in the Middle East, especially in
Saudi Arabia, Qatar, and Kuwait, and in North Africa. There are
also large fields in Indonesia, Nigeria, Mexico, Venezuela, Kazakhstan, and several U.S. states, including Alaska, California, Louisiana, and Texas.
Extracting petroleum

Once an oil company finds oil in the ground, it has to get the oil
out in order to sell it. First the company has to take care of legal
matters, such as getting rights to the area it wants to drill. Once
that is done, the company builds an oil well, or rig.
All oil rigs have the following basic elements:

A derrick, which is a tall structure that supports the drill
apparatus above ground

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A power source, such as a diesel engine, that powers electric
A mechanical system, including a hoist and a turntable
Drilling equipment, including drill pipe and drill bits
Casing to line the drill hole and prevent it from collapsing
A circulation system that pulls rock and mud out of the
A system of valves to relieve pressure and prevent
uncontrolled rushes of gas or oil to the surface

Some oil is located under the
oceans. Oil drilling platforms
are built on the water. These
platforms are off the coast of
Texas. ª Jay Dickman/

As oil workers drill deeper, they add sections of pipe to the drill
and add casings to the hole to keep it stable. They drill until they
reach the geologic trap that contains the oil and gas. To get the oil
out of reservoir rocks, workers pump in acid or a fluid containing
substances to break down the rock and allow the oil to seep into
the well. The workers then remove the rig and install a pump in its
place. The pump pulls the oil out of the well. Once the oil has been
removed from the ground, the oil company must transport the
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If Petroleum Formed in the Ocean, Why are Oil
Wells on Land?
When petroleum was forming, much of the area that is now dry
land was covered with water. The ocean has moved away
since then, but the oil is still there. In addition, many oil wells
are out in the ocean, not on land at all.

crude oil to a refinery. The most common means of transporting
oil are tanker ships, tanker trucks, and pipelines.
Making petroleum useful

Crude oil arrives at the refinery with a great deal of water and
salt mixed into it. The water and oil are mixed together in droplets
forming an emulsion, which is something like what happens to a
salad dressing made of oil and vinegar. The water and oil may
eventually separate out into their layers, but this process can take a
very long time in thick crude oil. To speed the process, oil refineries heat the crude oil to a temperature at which the water can
move more easily. The water molecules then come together and
leave the oil. The water also takes the salt out of the oil with it.
The refinery distills crude oil to sort it into its different forms.
Crude oil has many different kinds of molecules, some much larger
than others. The refinery sorts out these molecules so that molecules of the same size are all together. A refinery is shaped like a
tower with trays stacked one above the other. Heating the crude oil
makes the molecules turn into gases. These gases move up inside
the refinery’s tower. As they travel upward in the tower, the gases
become colder. At certain temperatures, they become liquids again.
The liquids drip back down and are caught in one of the trays. The
higher the gas travels, the higher the tray it ends up in. The largest
molecules stay at the bottom. The smallest molecules make it all
the way to the top of the tower. The lighter molecules are turned
into gasoline and other fuels. The heavier ones become engine
lubricants, asphalt, wax, and other substances.
There is a much larger market for gasoline and other fuels than
for the products made from heavier molecules, so refineries try to
make as much gasoline as possible. They can sometimes break
down larger molecules into smaller ones. They do this through a
process called cracking, which uses either heat or chemical catalysts to break down the large molecules.

Alternative Energy


The Oil Sands of Canada
Since the 1960s, investors and developers have been working to extract crude
oil stored in the oil sands of Alberta,
Canada. Some experts put the amount of
proven oil reserves in the western Canadian oil sands at roughly 175 billion barrels. This would put it second only to Saudi
Arabia (with 260 billion) in terms of proven
oil reserves. Others believe that the
amount of reserve oil in Alberta is much
higher, possibly at 300 billion barrels, with
more potentially buried deep underground.
Though people dreamed for decades of
striking it rich by getting the oil out of
Canada’s sand, techniques are still in the
early stages because of the difficulty of
removing it. When compared to the relative
ease of getting the oil that comes gushing
out of oil fields in the Middle East and
Texas, the existing process for turning oil
sand into crude oil is difficult and expensive. It requires oversized trucks and shovels to dig out the sand and various
machines to crush it, mix it with hot water,
spin it to separate out the oil, and heat it
to remove impurities. The expense concerned oil investors until political issues
in the Middle East and other oil-producing
nations and increasingly high demand in
the early 2000s drove up oil prices to
record levels, finally making oil removal
from Alberta’s sands profitable. With
demand for crude oil on the world market
growing, in particular to meet the needs of

the United States and China, many of the
residents and government officials of
Alberta and Canada saw the potential for
job creation and huge profits for the
province and the rest of the country. In
addition to making money by selling the
oil, Canada could also potentially use the
oil to negotiate with other countries on
trade and political issues.
In the decades to come, Canada may
become one of the biggest players in the
fossil fuel economy, though the benefits
may come at a high cost. The large
amounts of natural gas and water used in
the separation process create concerns
for environmentalists. So does the excavation of thousands of tons of mud and
sand, which creates large mining pits in
Alberta’s landscape. Though the oilmen
who run Alberta’s oil sand industry have
promised to improve technology to clean
up their greenhouse gas emissions and
refill the mines and replant trees, groups
like the Sierra Club of Canada have their
doubts about whether technology will progress fast enough or trees grow quickly
enough to make it worth the environmental
damage. With little encouragement for conservation and the use of alternate energy
sources by the worldwide community,
demand for crude oil will most certainly
transform Canada’s economy and landscape as the oil sands become a valuable
energy source for the world.

Current and potential uses of petroleum

Petroleum has many uses. It can take on different consistencies
depending on how much it is refined. About 90 percent of the
Alternative Energy



The Isla Oil Refinery in
Curacao, Netherlands
Antilles. ª 2005 Kelly
A. Quin.

petroleum used in the United States is used as fuel for vehicles.
Fuel types include:




Motor gasoline used to power automobiles, light trucks, or
pickup trucks that people drive as their daily transportation,
boats, recreational vehicles, and farm equipment such as
Distillate fuel oil, including the diesel fuel used to power
diesel engines in trucks, buses, trains, and some automobiles
Heating oil to heat buildings and power industrial boilers
LPGs (liquid petroleum gases), including propane and
butane. Propane is used for heating and to power
appliances. Butane is used as fuel and is blended with
Jet fuel, which is a kerosene-based fuel that ignites at a
higher temperature and freezes at a lower temperature than
gasoline, making it safer to use in commercial airplanes
Residual fuel oil used by utilities to generate electricity
Kerosene used to heat homes and businesses and to light lamps

Alternative Energy


Stopping the Knocking
The question of how to prevent engine knocking has occupied
petroleum engineers for many years. In the mid-twentieth
century, they added lead to gasoline to make it burn more
efficiently. In 1979 leaded gasoline became illegal in the
United States due to fears of lead poisoning in children. Since
that time MTBE (methyl tertiary-butyl ether) has been added to
gasoline in the United States to enhance octane. It has done a
great job of reducing emissions from car engines, but it is not
perfect. People are concerned that MTBE is dangerous when it
gets into drinking water, and they want to find a substitute.
Ethanol has been used in some cases, but it has drawbacks,
too. As of the early 2000s, oil companies were still looking for
the perfect fuel additive.


Aviation gasoline, which is a high-octane gasoline used to
fuel some aircraft
Petroleum coke used as a low-ash solid fuel for power plants
and industry

Petroleum has many other uses, including:

Petrolatum, or petroleum jelly, used as a moisturizer and
Paraffin wax used in candles, candy making, matches,
polishes, and packaging
Asphalt or tar used to pave roads or make roofs
Solvents used in paints and inks
Lubricating oils for engines and machines
Petroleum feedstock used to make plastics, synthetic rubber,
and chemicals

The United States uses over 250 billion gallons of oil every year.
About one-half of that amount comes from domestic wells; the
other half is imported.
Benefits and drawbacks of petroleum

As compared to other fossil fuels, petroleum is easy to retrieve,
refine, and use. It is fairly easy to transport and store. It is not
prone to exploding spontaneously, so it is relatively safe to keep
near homes. Petroleum burns easily, making it the ideal fuel for
Alternative Energy



internal combustion engines. Petroleum has many applications in
addition to fueling vehicles. These uses range from paving materials to skin moisturizers.
Using petroleum, however, has many drawbacks. It contributes to various types of environmental problems, including air
and water pollution. There is only a limited supply of petroleum, which means that at some time in the future, the world’s
petroleum will be gone. When that happens, people will have
to find another way of powering their vehicles, factories, and
Impact of petroleum

Using petroleum as fuel contributes to many environmental
problems. These include oil spills, which typically happen