Powering the Future: A Scientist's Guide to Energy Independence

by Daniel B. Botkin

  And that’s not all. People write about huge and unfamiliar numbers, like a quadrillion BTUs (a quad) and exajoules (don’t ask). Even the simple calorie that we’re all familiar with, the one listed on food packages, is actually an abbreviation of kilocalorie. The real (and little) calorie is the amount of heat energy that raises a gram of water from 15.5°C to 16.5°C. That’s so small an amount that dietitians talk in terms of a thousand of these—enough to raise a liter of water (about as much as a medium-size bottle of gin) that same 1°C.

  At least we come across calories (that is, kilocalories) and watts in our everyday modern life. But we rarely get to compare them. At the fitness center where we go to exercise, the Elliptical Trainer machine does it, showing us the watts and the calories that we generate per minute and that we therefore are using as we exercise. The other day I was using about 130 watts on the machine, enough to run one 100-watt light bulb with a little left over.13

  A historical perspective

  Our current energy crisis may seem unique, but it has happened to people and civilizations before.14 All life requires energy, and all human societies require energy. Although we can’t see and hold energy, it is the ultimate source of wealth, because with enough energy you can do just about anything you want, and without it you can’t do anything at all.

  Human societies and civilizations have confronted energy problems for thousands of years. Ancient Greek and Roman societies are a good case in point. The climate of ancient Greece, warmed and tempered by the Mediterranean Sea, was comparatively benign, especially in its energy demands on people. Summers were warm but not too hot, winters cool but not very cold. With the rise of the Greek civilization, people heated their homes in the mild winters with charcoal in heaters that were not especially efficient. The charcoal was made from wood, just as it is today. As Greek civilization rose to its heights, energy use increased greatly, both at a per-capita level and for the entire civilization. By the 5th century B.C., deforestation to provide the wood for charcoal was becoming a problem, and fuel shortages began to occur and become common. Early on in ancient Greece, the old and no longer productive trees in olive groves provided much of the firewood, but as standards of living increased and the population grew, demand outstripped this supply. By the 4th century B.C., the city of Athens had banned the use of olive wood for fuel. Previously obtained locally, firewood became an important and valuable import.

  Not surprisingly, around that same time, the Greeks began to build houses that faced south and were designed to capture as much solar energy as possible in the winter but to avoid that much sunlight in the summer. Because the winter sun was lower in the sky, houses could be designed to absorb and store the energy from the sun when it was at a lower angle but less so from the sun at a higher angle. Trees and shrubs helped.

  The same thing happened later in ancient Rome, but technology had advanced to the point that homes of the wealthy were centrally heated, and each burned about 275 pounds of wood every hour that the heating system ran. At first they used wood from local forests and groves, but soon the Romans, like the Greeks before them, were importing firewood.15 And again like the Greeks before them, they eventually turned to the sun. By then, once again, the technology was better; they even had glass windows, which, as we all know, makes it warmer inside by stopping the wind and by trapping heat energy through the greenhouse effect. Access to solar energy became a right protected by law; it became illegal to build something that blocked someone else’s sunlight.

  Some argue today that we should become energy minimalists and energy misers, that it is sinful and an act against nature to use any more than the absolute minimum amount of energy necessary for bare survival. But looking back, it is relatively straightforward to make the case that civilizations rise when energy is abundant and fall when it becomes scarce. It is possible (although on thinner evidence) to argue that in the few times that democracy has flourished in human civilizations, it has done so only when energy was so abundant as to be easily available to most or all citizens.

  As a result, in this book I argue for changes in where and how we get and use energy, but I do not argue that we should become energy minimalists or energy misers. On the contrary, I think we need to learn how to use as much energy as we can find in ways that do not destroy our environment, do not deplete our energy sources, and do not make it unlikely that our civilization will continue and flourish in the future.

  The path to such a world is possible but not simple, not answered with a slogan, not solved by a cliché. If you value your standard of living and the way of life that our modern civilization provides, with its abundant and cheap energy, follow me through this book as we examine each energy source and the ways in which some can be combined into viable energy systems for the future.

  A traveler’s guide to this book

  Each of the first nine chapters discusses a major source of energy: how much energy it provides today, how much it could provide in the future, how much it would cost, and its advantages and disadvantages.

  We begin with conventional fuels—fossil fuels, water power, and nuclear fuels—energy sources that dominated the 20th century. We then go on to the new energy sources, those that may have played small roles in the past but are now viewed as having major energy potential. In addition, we devote a chapter to energy conservation. The last part of the book talks about larger and broader issues that involve, or could involve, some or all energy sources: how to transport energy; how to transport ourselves and our belongings; how to improve energy efficiency in our buildings.

  And finally, in the last chapter, I attempt to put the whole thing together in formulating a first approximation of an achievable and lasting solution to our energy problem.

  Section I. Conventional energy sources

  I use the term conventional to mean those energy sources that dominated the 20th century, are familiar to us, and therefore seem conventional. These are the fossil fuels—oil, gas, and coal—as well as water power from rivers and streams, and nuclear power.

  In working through the energy issues myself, I kept needing to refer back to the broad view of how much energy each source provided and might provide in the future. Table SI.1 and Figure SI.1 provide a quick summary, which you may want to refer back to. I also found it hard to conceive of energy amounts this large, so I tried to express them as something I could imagine. That’s why Table SI.1 shows how many Boeing 747 round-the-world trips each amount of energy could provide.

  Table SI.1 U.S. Energy Use 20071

  Figure SI.1 Total energy consumption in 2007 for (top) in the United States and (bottom) in the world. The zeros for wind, solar, and others in the top chart mean less than 0.5%, not exactly zero.

  I have shown the energy use both in a table and in a graph, because some people relate more easily to one and some to the other.

  Putting a number on the total amount of energy people use requires the use of two of those terms we previously mentioned. Total energy use in the United States is approximately 29,000 billion kilowatt-hours (refer to Figure S.1 and Table S.1). To be specific for our later calculations, the amount we use is 29,590 billion kilowatt hours. Worldwide, people use about 116,000 billion kilowatt-hours. Note that the United States uses about 22% of all the energy consumed in the world!

  Putting some reality into energy

  We talk about large amounts of energy and power, and these have little reality, both because the numbers are big and because energy is invisible, so we can’t picture its quantity. Here are a few comparisons that may help. A typical number we will deal with is a million kilowatts of power, which, for example, is the capacity of a typical nuclear power plant reactor. What can we do with that amount of power? If that power plant runs an hour, that gives us 1 million kilowatt-hours, another large and abstract number. Table SI.2 shows what that amount of energy can do.2 For example, that’s the equivalent of more than 9,000 100-watt light bulbs burning around the clock, day in and day out, for every man, woma
n, and child in the United States.3 It is also equivalent to more than 9 round-the-world trips by a Boeing 747.

  Table SI.2 What You Can Do with the Output from a Typical Large Electrical Power Plant

  The first simple message from these numbers is: We use a lot of energy!4

  The second simple message is that in industrialized nations, most energy comes from fossil fuels.

  Conclusion: Of the conventional fuels, only freshwater provides renewable energy. Nobody doubts that eventually the others—fossil fuels and conventional nuclear fuels—will run out. The important questions follow: When will this happen? What are the environmental and economic effects of these fuels in the near and distant future? How do we make a transition away from them? And when do we have to do that? Economists will tell you that running out of a fuel source isn’t simply a question of the total amount in the ground and the rate at which you pull it out. There will always be some amounts of fossil fuels in the ground, but a point will be reached when the costs to extract these exceeds the price at which they could be sold as fuel. Eventually, a tiny amount of coal that is left—can you believe this?—might become so rare as to be a treasure, something people might frame and mount on a wall at home to show the fossil leaf of a tree that once lived and was turned into coal.

  Economically recoverable means that a mining company can sell the coal it obtains at more than it cost to mine it. Physicists and mining engineers will also tell you that a fossil fuel has to be energetically recoverable, which means that the amount of energy in the fuel at the point of use is greater than the energy expended to obtain it and transport it to that location. This includes the energy costs of all indirect activities, such as pollution control resulting from mining, other production costs, and transportation.

  There is a subtext in these chapters as well. If we have to move away from nonrenewable energy sources simply because they aren’t renewable, what is stopping us from doing so? Is it politics, or big money, or our personal preferences, or something about the way our society is set up that forces us to use energy in certain ways, or what? I explore this to the extent that I can, but you may have some ideas about this, too.

  We begin, then, with where we are now and what the consequences of our present condition are for us and for the world.

  1. Oil

  Figure 1.1 A modern oil-drilling ocean platform. Platform Holly, a few miles off the coast from Santa Barbara California, was installed in 1966 and has produced oil since. (Source: Linda Krop, Environmental Defense Center, Santa Barbara, CA)

  Key facts

  • Worldwide, people use about 30 billion barrels of oil a year, which works out to 210 gallons per person. The worldwide total is expected to increase to 50 billion barrels a year—350 gallons per man, woman, and child—in the next few decades.

  • In 2005, the United States used 28% of all the oil consumed in the world.

  • In recent years, the United States consumed about 7.5 billion barrels of petroleum a year, dropping to 7.1 billion barrels 2008 (23% of the world’s total consumption). More than 60% is imported; 17% of that is from the Persian Gulf.

  • Two-thirds of all transportation energy in the United States comes from petroleum—2.2 billion gallons a day: 55% of this for ground transport of people, almost 36% for ground transport of freight, and just under 10% for air transport of both people and freight.1

  • According to conventional estimates, at the current rate of use Americans will run out of oil in less than 50 years.

  It’s a stretch, but imagine you’re an Eskimo living 1,500 years ago

  It’s around A.D. 500, and you’re part of a small group of Eskimos struggling northeast in Siberia near the Bering Strait and crossing by boat into what is now Alaska. There you find other Eskimo groups whose lives are a struggle—living at the margin, barely enough food, hard to do anything but try to keep warm and figure out where the next meal will come from. This was the life of most Canadian Eskimos at that time, a struggle for existence.

  But according to anthropologist John R. Bockstoce, an expert on Eskimo culture and Eskimo and Yankee whaling, you and your Eskimo relatives coming from Siberia, called the Birnirk culture, brought with you inventions for hunting. One of these was a harpoon made of bone and antlers that, like a modern whaling harpoon, would slide closed into the flesh of the whale and then lock in an open position when the whale tried to swim away. Your group also had kayaks, umiaks, and drag-float equipment and began using these devices to hunt whales. This led to a fundamental change in your lives. Whale meat and oil gave you so much more energy than your neighbors that your group did much more than simply hunt and think about the next meal. With the basic necessities of life—food and shelter—assured, people could use their surplus energy and time in more enjoyable ways: telling stories, painting pictures, singing—in other words, being “civilized” in the modern sense. Or if they were concerned that their food supply might dwindle, they could use that excess energy and time to acquire more territory, more food, more power—in other words, to wage war.2 The ability of early Eskimos to obtain meat and oil from whales is analogous to our ability to get petroleum cheaply and easily from the ground. As long as it was available that way, we could while away our leisure time with video games, golf, travel, and whatever else we wished. But by now almost everyone understands that petroleum is a finite resource that will be used up pretty soon if we continue to rely on it as one of our major sources of energy. Moreover, it’s equally clear that the use of petroleum, rather than declining, is going to increase, especially since the huge populations in China and India are rapidly increasing their ownership and use of automobiles.

  Where does petroleum come from?

  The fossil fuels—petroleum, natural gas, and coal—are just that, fossils. Coal was formed from the remains of trees and other woody plants, covered by soil and then buried deeper and deeper and subjected to heat and pressure, which converted their remains to mostly carbon, but with a fair amount of other elements that were part of the plants and the surrounding soil (for more on this, see Chapter 3, “Coal”). Petroleum and natural gas are believed to be the fossil remains of marine organisms.

  All fossil fuels that we take out of the ground today were produced eons ago from the growth of photosynthetic organisms—algae, certain bacteria, and green land plants, organisms that can convert the energy in sunlight into energy stored in organic compounds, and do so by removing carbon dioxide from the atmosphere and releasing pure oxygen. The energy that fossil fuels contain is thus a form of solar energy, in most cases provided over many millions of years and stored since then.

  Over time, much of the carbon from the carbon dioxide that algae, green plants, and some bacteria removed from the atmosphere was then sequestered—stored in the soils, rocks, and marine deposits, and prevented by various physical and chemical processes from returning to the atmosphere. When fossil fuels are burned, the sequestered carbon is released into the atmosphere as carbon dioxide (CO2), which acts as one of the primary greenhouse gases.

  Since petroleum and natural gas are not solids and thus are lighter than the rocks that surround them deep in the Earth (Figure 1.2), they tend to rise under pressure from the rocks and get trapped in geological pockets, like the one shown in Figure 1.3—although in some rarer situations the oil makes it to the surface, as it does in Southern California. Thus, the search for oil and gas is not random; petroleum geologists know which kinds of rock formations they are likely to occur in.

  Figure 1.2 A typical location of oil and gas. Oil or gas rarely gets pushed right up to the surface, as it does at the La Brea pits in Los Angeles, famous for having trapped many ancient and extinct mammals whose fossils have become familiar. (Source: D. B. Botkin, and E. A. Keller, Environmental Science: Earth as a Living Planet. New York, John Wiley, 2009)

  Figure 1.3 A natural oil seep along the California shore at Santa Barbara. Pressure from surrounding rocks has pushed petroleum up to the surface, where it flows into the
Pacific Ocean, revealing itself by its bright reflection of sunlight. (Courtesy of the University of California, Santa Barbara, UCSB Map & Image Laboratory, from the research collection of Prof. Jack E. Estes)3

  How much energy does petroleum provide?

  In recent years, the United States consumed about 7.5 billion barrels of petroleum a year, dropping to 7.1 billion barrels 2008. More than 60% of petroleum is imported; 17% of this from the Persian Gulf.4 Petroleum provides about 37% of the world’s energy and 41% of the energy used in the United States,5 most of which is used for transportation. The United States alone uses 8.4 billion barrels of oil a year. According to the U.S. Department of Energy, essentially all the energy used in transportation in the United States comes from fossil fuels,6 and two-thirds of all transportation energy in the United States comes from petroleum: 2.2 billion gallons a day—55% (1.2 billion gallons a day) for ground transport of people, almost 36% (789 million gallons a day) for ground transport of freight, and just under 10% (210 million gallons a day) for air transport of both people and freight.7 In contrast, petroleum provides only 1% of the electricity produced in the United States.8 Most electricity in the United States is produced from coal, hydropower, and nuclear power. To keep things simple, think about petroleum as the transportation fossil fuel.