The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
Coal, petroleum, and natural gas are referred to as fossil fuels. Their common origin is as living matter, plants, and, in particular, microorganisms that have accumulated in large quantities under favorable conditions during the earth's long history. They have been preserved (fossilized) through burial under younger sediments, to great depths and over many millions of years. The "organic" elements hydrogen (H) and carbon (C) are the primary source of their heat content (hence the derivation of the word hydrocarbons). Coal has a relatively high carbon content; petroleum and natural gas have much higher hydrogen contents. The burning of fossil fuels releases large quantities of the powerful greenhouse gas carbon dioxide (CO2) into the atmosphere, where it remains for a long time and contributes to global warming.
Fossil fuels have powered the industrialization of the world for several centuries. During the nineteenth and early twentieth centuries, coal was the primary source of energy. Then, after World War I, petroleum and later natural gas became increasingly important and together they contribute approximately 62 percent of the primary energy sources in the United States. Coal nevertheless still provides about 23 percent, mostly by conversion into electricity at large power plants.
Energy Information Administration. "Monthly Energy Review." Available from http://www.eia.doe.gov/emeu/mer.