Energy in the 21st Century

John R Fanchi, Christopher J Fanchi;;;

• Publisher: WSPC
• Year: 2016
• eBook ISBN: 9789813144804
• Edition: 4
• Topic: Technology & Engineering
• Subtopic: Global Warming & Climate Change
• Index: Technology & Engineering

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Energy in the 21st Century is a valuable source of information for students, decision makers, opinion leaders, and the general public. Oil and natural gas price volatility continue to affect both the supply and demand for energy. Advances in other technologies, such as nuclear, wind, solar, and tidal technology, are altering the comparative economics of competing energy sources. New government policies are changing the landscape of the global energy marketplace.

From our reliance on fossil fuels to the quest for new sources of energy, Energy in the 21st Century provides a fact-based analysis of the most prominent energy issues of our time. The fourth edition updates data and includes more discussion of recent advances. Some of the highlights of the fourth edition are expanded discussion of climate change and anthropogenic climate change; the 2015 COP21 Paris Agreement on Climate Change; nuclear fusion reactor prototypes (tokomak ITER and stellarator W7-X); advances in solar thermal and solar photovoltaic power plants, space based solar power, transparent photovoltaic cells, and hybrid solar wind technology; tidal and wave energy converters; oil from algae; the EU Supergrid; the Goldilocks Policy for energy transition and the Grand Energy Bargain.

Energy in the 21st Century has been used as the text for the general college student population, as well as energy overview for MBA students. Pedagogical material includes learning objectives at the beginning of each chapter, end of chapter activities, a comprehensive index, a glossary, and an Appendix to help with converting units. Points to Ponder are provided throughout the text and are designed to encourage the reader to consider material from different perspectives.

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CHAPTER 1

A BRIEF HISTORY OF ENERGY CONSUMPTION

After reading this chapter, you should be able to…

Define energy and how it is used

P2P*: What does an energy unit mean to me?

Define energy density and explain its significance

P2P: Why is energy density important?

Describe historical energy consumption

Connect energy consumption to quality of life

P2P: Using quality of life to forecast energy consumption

Discuss the transition from wood to coal to oil to a broad energy mix

P2P: Why should I care about the global distribution of energy?

* Point to Ponder

We all make decisions about energy. We decide how much electricity we will use to heat or cool our homes. We decide how far we will travel every day and the mode of transportation we will use. Those of us in democratic societies choose leaders who create budgets that can support new energy initiatives or maintain a military capable of defending energy supply lines. Each of these decisions and many others impact the global consumption of energy and the demand for available natural resources. The purpose of this book is to give you the information you need to help you understand the issues and make informed decisions.

The choices we make today will affect generations to come. What kind of future do we want to prepare for them? What kind of future is possible? We can make the best decisions by being aware of our options and the consequences of our choices. In this book, we consider the location, quantity and accessibility of energy sources. We discuss ways to distribute available energy, and examine how our choices will affect the economy, society, and the environment. We begin by defining energy and reviewing our history of energy consumption.

1.1WHAT IS ENERGY?

Energy is the ability to do work. It can be classified as stored (potential) energy, and working (kinetic) energy. Potential energy is the ability to produce motion, and kinetic energy is the energy of motion. Forms of energy include energy of motion (kinetic energy), heat (thermal energy), light (radiant energy), photosynthesis (biological energy), stored energy in a battery (chemical energy), stored energy in a capacitor (electrical energy), stored energy in a nucleus (nuclear energy), and stored energy in a gravitational field (gravitational energy).

Sources of energy with some common examples include biomass (firewood), fossil fuels (coal, oil, natural gas), flowing water (hydroelectric dams), nuclear materials (uranium), sunlight, and geothermal heat (geysers). Energy sources may be classified as renewable or nonrenewable. Nonrenewable energy is energy that is obtained from sources at a rate that exceeds the rate at which the sources are replenished. Examples of nonrenewable energy sources include fossil fuels and nuclear fission material such as uranium. Renewable energy is energy that is obtained from sources at a rate that is less than or equal to the rate at which the sources are replenished. Examples of renewable energy include solar energy and wind energy.

Renewable and nonrenewable energy sources are considered primary energy sources because they provide energy directly from fuels. A fuel is a material which contains one form of energy that can be transformed into another form of energy. Primary energy is energy that has not been obtained by anthropogenic conversion or transformation. The term “anthropogenic” refers to human activity or human influence. Primary energy is often converted to secondary energy for more convenient use in human systems. Secondary energy sources are produced from primary sources of energy and can be used to store and deliver energy in a useful form. Hydrogen and electricity are considered secondary sources of energy, or “carriers” of energy.

1.1.1Energy Transformation

Modern civilization depends on the observation that energy can change from one form to another. If you hold a book motionless above a table and then release it, the book will fall onto the table. The book has potential energy when it is being held above the table. The potential energy is energy associated with the position of the book in a gravitational field. When you drop the book, the energy of position is transformed into energy of motion, or kinetic energy. When the book hits the table, some of the kinetic energy is transformed into sound (sonic energy), and the rest of the kinetic energy is transformed into energy of position (potential energy) when the book rests on the table top.

Energy transformation is needed to produce commercial energy. As an illustration, suppose we consider a coal-fired power plant. Coal stores energy as chemical energy. Combustion, or burning the coal, transforms chemical energy into heat energy. In steam power plants, the heat energy changes water into steam and increases the energy of motion, or kinetic energy, of the steam. Flowing steam spins a turbine in a generator. The mechanical energy of the spinning turbine is converted to electrical energy in the generator. In a real system, energy is lost so that the efficiency of electrical energy generation from the combustion of coal is less than 100%. A measure of the energy that is available for doing useful work is called exergy.

Real power systems transform energy into useful work, but some of the energy is wasted. The energy efficiency of a system is the amount of energy needed by the system to perform a specific function divided by the amount of energy that is supplied to the system. Energy efficiency has a value between 0% and 100% and is a measure of the lost as non-useful energy. For example, suppose we have two light bulbs A and B. Both light bulbs provide the same amount of light, but light bulb B produces less heat than light bulb A and uses less energy than light bulb A. Consequently, light bulb B has higher energy efficiency than light bulb A because light bulb B uses less energy to achieve its intended purpose, to provide light.

In the light bulb example, we can reduce energy consumption by adopting a more energy efficient technology. Another way to reduce energy consumption is to turn off the light when it is not needed. In this case, we are conserving energy by changing our behavior. Energy conservation can be achieved by adopting a behavior that results in the use of less energy. An improvement in energy efficiency or conservation can be viewed as increasing the supply of useful energy because the improvement lets us get more value from existing energy sources.

Point to Ponder: What does an energy unit mean to me?

To get an idea of the meaning of an energy unit such as kilocalorie or megajoule, it is helpful to compare the energy consumed by the operation of modern devices. For example, a 1200 Watt hair dryer uses approximately one megajoule of energy in 15 minutes. A megajoule is 1 million Joules, which can be written as 10⁶ Joules or 10⁶ J. A 100 Watt light bulb uses approximately one megajoule of energy in about three hours. [Fanchi, 2004, Exercise 1-3]

If we run the 1200 Watt hair dryer for one hour, we will use 1.2 kilowatt-hours of energy. We abbreviate 1.2 kilowatt-hours as...

Table of contents

• Cover Page
• Title
• Copyright
• Preface to the Fourth Edition
• Dedication
• About the Authors
• Contents
• 1 A Brief History of Energy Consumption
• 2 Fossil Energy – Coal
• 3 Fossil Energy – Oil and Gas
• 4 Energy in Transition
• 5 Nuclear Energy
• 6 Renewable Energy – Solar Energy
• 7 Renewable Energy – Wind Energy
• 8 Renewable Energy – Energy From Water
• 9 Renewable Energy – Bioenergy and Synfuels
• 10 Energy Carrier, Energy Storage and Hybrid Energy Systems
• 11 Electricity Generation and Distribution
• 12 Energy Economics
• 13 Future Issues – Geopolitics of Energy
• 14 Future Issues – Energy Forecasts
• Appendix A
• Appendix B
• Appendix C
• Appendix D
• References
• Glossary
• Index