Back to Energy and the Environment: Sources, Technologies, and Impacts Home
Table of Contents
Energy and the Environment: Sources, technologies, and impacts Hope has two beautiful daughters: anger and courage; anger at the way things are, and courage to change them ~ St. Augustine. Destiny is not a matter of chance, but of choice. Not something to wish for, but to attain. ~ William Jennings Bryan (1860-1925) Preface Energy is arguably the most fundamental concept in all of science and beyond. Chemical reactions are driven to a large extent by energy considerations. So are bowling balls and roller-coasters. Politicians worry about energy shortages and cosmologists suspect that an excess of energy is driving the expansion of the universe. The concept of energy is found everywhere. Energy comes in many forms and, depending on whether or not it can replenish itself in a relatively short time, can be classified as renewable or non-renewable. Today’s world, however, is powered mainly by nonrenewable fossil fuels— coal, oil and natural gas. Oil is particularly important because it is liquid and thus conveniently transported. It is also a key component of numerous clothing, pharmaceutical, and construction products. Only 1% of all energy consumption is fulfilled by renewable sources: solar, wind, waves, and geothermal; 88% comes from fossil fuels, while nuclear and hydroelectric account roughly equally for the remaining 11%. Fossil fuels are, however, of limited supply, and unless huge new deposits are discovered, they will soon deplete. It is estimated that at the current rate of consumption, we will run out of oil in 40 years, natural gas in 60, and coal in 180 years. If the growth in demand is considered, especially that in many developing countries, these numbers will be even lower. The United States, the most industrialized nation, is particularly dependent on oil. Oil consumption in this country accounts for roughly 26% of the world’s. Today, about 60% of the US oil comes from abroad, as compared to about 40% in the early 1990s. As more countries become industrialized, the rate of consumption grows rapidly. Consumption in China and India in particular is expected to grow by two-thirds in the next quarter century. Although this book is written at a level suitable as a textbook for introductory course in energy and environment for undergraduate students with very little mathematics or science background, it can be read by anyone interested in technical, political, environmental, and xv economical issues related to energy. To provide material appropriate for engineering and science students, additional topics are included in the appendices and in various boxes. This manuscript is divided into seventeen chapters. In Chapter 1, we introduce general concepts related to energy and its sources, reserves, production and patterns of use. Chapter 2 deals with mechanical forms of energy and the concepts of work, power, and simple machines. Wind power and hydro power are two aspects of mechanical energy and are discussed in Chapters 3 and 4, respectively. In Chapter 5, we introduce the reader to concepts of temperature, heat, and principles of thermodynamics. Furthermore, we show how these concepts can be used to design practical machines ranging from internal combustion engines and electricity-generating power plants to refrigerators, air conditioners, and heat pumps. Next, we introduce the chemical forms of energy, and its storage as biomass through photosynthesis (Chapter 6), or as fossil fuels (Chapter 7). The environmental consequences of fossil fuel combustion are discussed in Chapter 8. Geothermal energy is one source that provides thermal energy directly without the need to burn biomass or fossil fuel (Chapter 9). The radiation from the sun can also be used as a source of heat and light to use in our residential and commercial buildings, or to generate electricity; these topics are covered in Chapter 10. The energy released by nuclear reactions and the benefits and dangers of radiation exposure are discussed in Chapters 11 and 12 respectively. In Chapter 13, we cover the basics of electricity generation, storage, transportation, and distribution. A short review of transportation technologies is given in Chapter 14. A brief overview of modern economic theories is given in Chapter 15, and is used to evaluate merits of different energy technologies. The economics of the environment and costs associated with environmental damage and cleanup technologies are given in Chapter 16. In the final chapter (Chapter 17) we define sustainability from economic and environmental perspectives, address issues associated with globalization, and offer a possible roadmap for a sustainable future. Each chapter is concluded with a list of additional resources, exercises, and one or more mini-projects. For easy reference, all essential data, formulas, and tables of unit conversions are compiled in four appendices and a glossary of terms at the end of the book. The book is structured in a highly modular form applicable to a wide range of audiences including engineering and science majors, liberal arts students, and the general public. Each chapter stands alone and the text can be taught in any order that the instructor deems suitable. Widely different curricula can be designed and tailored to any audience simply by selecting to focus on sections from different chapters without loss of generality. For example, an environmental engineering course may include a summary of various energy technologies, with xvi emphasis on air pollution, radiation, and environmental economics; a science curriculum may emphasize various technologies and incorporate some engineering designs. In the course of writing the text, great care was taken to avoid excessive detail while emphasizing the fundamentals of energy and important environmental and technological concepts. Except for a few very simple equations, all equations are given in boxes labeled “Mathematical Interlude…” can be excluded by non-science, non-engineering majors. Information thought to be advanced or of interest to a specific group is placed between two icons and , indicating the beginning and end of such material. Additional information is also provided in capsulated forms in separate boxes titled “Digging Deeper...”, “FYI...”, “Point/ Counterpoints...”, and “Did You Know That...?”. Writing a textbook is no easy task and is rarely, if ever, accomplished without help from others. I wish to take the opportunity to thank my many colleagues and friends who made valuable suggestions, edited the manuscript, or assisted in design and layout. Dr. Hamid Hefazi offered constructive comments for the chapter on wind energy. A big thanks to Dr. Abas Goodarzi, who contributed valuable insights on the chapters dealing with electricity and transportation systems, to Dr. Adel Alapour for review and helpful comments of chapter on nuclear energy, and to Professors Darwin Hall and Ali Toossi Ardakani for their critique on chapters regarding the economics of energy and the environment. I also had many helpful discussions with long-time colleague and a coauthor on an upcoming physics text, Dr. Igor Glozman, professor of physics and astronomy, about the organization and presentation style. Mses. Emilie Ryan and Whitney Graves proofread the manuscript, Ms. Shiori Amano prepared the bulk of the graphics, Ms. Nicky Mohd helped in design of the book layout, and Ms. Joyce Kwon designed the book cover. Thanks also to Dr. Babak Mikhak for his artistic talents for design of a companion website. Finally, this book would not have been possible if it were not for valuable suggestions of numerous students who took a GE course with the same title in recent years at California State University, Long Beach. As a final note, any manuscript is prone to have a certain number of typographical errors, at least in the first edition. In the case of this publication, the typographical errors have actually been planted on purpose, and that purpose is suggested by the famous American cartoonist R andy Milholland: “Typos are very important to all written form. It gives the reader something to look for so they aren’t distracted by the total lack of content in your writing.” Reza Toossi May 5, 2006 Long Beach, California xvii Preface to the Second Edition Since the first edition of the text was published in May 2006, there have been major changes in the world energy situation. The market price of petroleum has spiked from $36 a barrel to $130 at the time of this writing in May 2008; retail prices of gasoline in the US have increased from $2.78 a gallon to $4.00 a gallon in the past two years. Indonesia, one of the major suppliers of oil in the last few decades, has become a net importer of oil and is cancelling its membership in OPEC. Over the past decade China has nearly doubled its oil consumption and is expected to double it again in the next decade. Similarly, other non-OECD countries are demanding higher and higher percentages of the total world petroleum output. During these happenings, the political instability in the Middle East and other oil rich countries are spreading. The US occupation of Iraq continues with no end in sight, and now rumors of an impending war with Iran are being circulated. In Nigeria, despite a cease fire signed by the government and various rebel groups, pipeline sabotage and kidnappings of foreign workers are routinely interrupting oil operation. As a result, the Nigerian oil production has decreased by 15 percent in the past two years. Similarly, in Algeria, terrorist attacks targeting oil facilities have sparked concern among foreign oil companies operating in North Africa. Thanks to skyrocketing oil prices, oil companies are enjoying record profits. Only three oil companies, Chevron, Exxon-Mobil, and Royal Dutch Shell, reported combined net profits of 90 billion dollars in 2007, the single largest annual profit in US corporate history. As the world is waking up to the realities of energy scarcity, there are works in progress to develop new and alternative sources of energy. Progresses in generating electricity from waves, solar sources, and wind are being reported. Hybrid vehicles are slowly gaining traction, although fuel cell cars still remain a distant goal. New findings show that, contrary to original beliefs, biofuels do not reduce greenhouse emissions and may in fact divert vast resources away from food production. The recent shortages in food supply around the world is partly due to the fact that subsidies many farmers receive to plant corn and other crops to make biofuels is more than what they would earn from cultivating food crops. The situation is expected to get worse in near terms. A new UN report on the effects of global warming on climate patterns, land resources, and vegetation is sobering. The trends point to a complicated blend of changes including violent shifts in weather patterns, disruption in patterns of food production, and restrictions on the availability of fresh water resources. As of April 2008, 178 countries have ratified the Kyoto Protocol, leaving the United States as the only major country refusing to abide by the treaty. There have been failures and successes, but the final verdict on the success of the protocol is still out. xviii This second edition is being prepared out of necessity to reflect the dynamic nature of energy resources, emerging technologies, and associated environmental implications. In addition to substantial editorial changes, the new edition will differ from the previous edition in the following ways: 1. The course content has been expanded and reorganized to reflect a more natural flow of the subjects. 2. All graphs, charts, and tables are updated to reflect the latest data available from reputable resources. 3. New scientific findings, technological advances, and economical theories are incorporated and their merits are discussed. 4. Additional examples are provided throughout the text, and supplementary exercises and mini-projects are given at the end of each chapter. Reza Toossi, May 2009 xix xx