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

by Daniel B. Botkin

  Biofuels attract a lot of government funding and private investment in countries such as China and Brazil that lack large petroleum reserves and have a lot of land that is either not in use for food crops or only marginally productive for food. For these nations, biofuels offer at least a short-term gain, although at a large long-term cost in terms of food production and the environment. The Chinese Academy of Forestry has identified 1,553 species of oil-bearing woody plants that might be used to make biodiesel fuel.63 Companies in the Hebei province of northern China are said to be processing more than 20,000 tons per year of pistachios for biofuels. The claim is that the nuts have an oil content greater than 40%, which makes them a good source, and that pistachio trees can be grown in mountains and hills unsuitable for farming. The company says there are 160,000 acres of such land available and that the pistachio yield averages slightly more than seven tons per acre per year.64

  In the U.S. today, hundreds of biodiesel plants produce fuel in many states, and among owners of small farms there is a rapidly growing interest in biofuels, especially biodiesel fuels. Cooperatives are springing up around the country, with members who are interested in sustainable agriculture and improving the environment, and who view the benefits of local production of biofuels, especially biodiesel, as outweighing doubts. One such organization, the Piedmont Biofuels Cooperative of North Carolina, writes on its website: “Our mission is to lead the grass-roots sustainability movement in North Carolina by using and encouraging the use of clean, renewable biofuels.” 65

  College courses in biofuels are springing up as well, such as the Biofuels Program of Central Carolina Community College.66

  This is an interesting situation, in which one cannot but applaud the enthusiasm and desire to do good locally. The question is whether, even locally, with transportation minimized and with many related tasks done sustainably, the net result can be energy-efficient, environmentally sustainable, and economically profitable.

  The scientists who analyzed the production of ethanol from sugarcane in Brazil and corn in the United States, and concluded that the environmental and economic consequences outweighed any benefits, nevertheless suggest that “the ethanol option probably should not be wholly disregarded.” They explain:

  The use of a fuel that emits lower levels of pollutants when burned can be important in regions or cities with critical pollution problems. Also, in agricultural situations where biomass residues would otherwise be burned to prepare for the next planting cycle, there would be some advantage in using the residues for alcohol production. However, further research should be done to improve the conversion process. Considering that, eventually, petroleum may no longer be available in the amounts currently consumed, one must conclude that substitution of alternatives to fossil fuel cannot be done using one option alone. It will prove more prudent to have numerous options (e.g., ethanol, fuel cells, solar energy), each participating with fractional contributions to the overall national and global need for fuel energy.67

  The bottom line

  • Fuels produced by algae and soil bacteria seem to hold the most promise for culturing and growing species with the goal of producing usable energy.

  • Agrifuels—crops grown on the land with the goal of producing fuels—cannot fill a significant percentage of our energy needs. Currently, even the most optimistic estimates indicate that it would take all the cropland planted today in the United States just to fuel all of our automobiles.

  • Even when the net energy balance is positive—that is, when we get more energy from a crop than we used to produce it—biofuels seem to produce more environmental damage than benefits.

  • Burning waste as fuel is a valuable way to get rid of undesirable chemicals, but waste, too, can never satisfy more than a small percentage of our total energy requirements.

  • If we seek to reduce the net release of carbon dioxide into the atmosphere, it appears better to slow deforestation than to grow crops for fuel. An acre of forest stores more carbon than would be gained by converting an acre of cropland from crops for food to crops for fuel.

  • Turning biological waste into fuel is in general a good idea, even when energy efficiency is less than 1—it’s just a smart way to get rid of waste. But you can’t estimate the energy efficiency or carbon benefits as if the fuel just suddenly appeared at a gas pump with no costs associated with its original production.

  • For household use where no other fuels are available, firewood, animal dung, and other local sources are necessities for heating and cooking. The problem is how to make these into sustainable products that minimize environmental damage.

  • Crops grown for biofuels today are not cost-effective, are damaging to the environment, and threaten biodiversity. In the future, as more is learned about them, they will probably have a niche role and be important in certain nations.

  • Burning organic wastes and using firewood that is harvested following sustainable practices are good things to do and will play a definite if not major role in world energy supplies. Firewood will remain important in rural areas and in poor nations, at least until small windmills and small solar installations take over.

  Section III. Designing an energy system

  Now that we have explored each of the sources of energy, we can turn to the important and more general question: How can we design an energy system for the future that will provide abundant energy, and much greater energy independence, with the best combination of energy sources and the greatest reliability and cost efficiency? This involves some larger-scale questions, including how we will transport energy, how we can use energy to transport ourselves and our goods most efficiently, and how we can improve the energy efficiency of our buildings. Finally, in the last chapter I discuss possible solutions and try to put the entire story together.

  10. Transporting energy: the grid, hydrogen, batteries, and more

  Figure 10.1 On June 10, 1999, a pipeline transporting gasoline exploded near Bellingham, Washington, a rare accident, killing three boys and causing considerable local environmental damage. Some 230,000 gallons of gasoline were spilled and one and a half miles of Whatcom Creek were damaged, killing an estimated 100,000 fish. Smoke from the explosion rose six miles. (© AP images)1

  Key facts

  • The U.S. energy transport network is huge. Some 90,000 miles of oil pipelines, 2 million miles of natural-gas pipelines, and 700,000 miles of electrical transmission lines transport much of the energy from where it is obtained to where it is used.

  • America’s natural-gas pipelines have had a good safety record, but all energy transportation systems are vulnerable to terrorism and accidents, which could have far-reaching effects.

  • Ironically, the most technologically advanced form of our energy—electricity—has the most outdated, inadequate, and vulnerable transport network, the electric grid.

  • If present trends continue, peak electricity demand will be unmet in five years for most of the United States unless we rapidly expand our transmission system. A hydrogen economy, where a society produces and uses energy primarily or largely in the form of hydrogen, is a popular proposal today. But the United States lags other nations—including Japan, Germany, and Denmark—in research and development to create such an economy.

  Pipelines: one way to get energy where you need it

  When we think about transporting energy—if we think about it at all—we picture high-tension power lines marching across the landscape. Aware of it or not, however, electricity is not the only form of energy that must be transported long distances before we use it. Gasoline, for example, travels a long way from refineries via pipelines, rail cars, and trucks before it gets into your car’s tank.

  One of the many problems associated with Americans’ dependence on fossil fuels is that the places where the fuels originate are usually far removed from where they are most heavily used. For example, East Coast states, with their high human populations, receive 60% of the refined oil products shipped
within the nation and almost all the refined oil products imported into the nation.2

  Mostly it takes a disaster or a hugely inconvenient disruption to make us suddenly aware of energy transportation. Sometimes the attention-getter is a major oil spill, like that of the Exxon Valdez, or news of a spectacular explosion when a pipeline bursts or a railway car or truck carrying gasoline overturns, as happened on June 10, 1999, in Bellingham, Washington. It was hard to miss this explosion if you were in Bellingham or nearby—the smoke rose six miles into the air, and more than a mile of gasoline several inches thick slid down Whatcom Creek in the town. The next year, in August, 2000, a gasoline pipeline exploded near Carlsbad, New Mexico, and killed 12 members of a family camped nearby. As a result, in March 2002, Senators John McCain and Patty Murray authored the Pipeline Safety Improvement Act as an amendment to the Senate energy bill (S 517).3

  When I talk with people about alternative energy sources such as solar and wind, inevitably someone asks what we’re going to do about running cars when all we are producing is electricity. Once in a while, someone may ask about the electrical grid, especially right after a major blackout, but I can’t remember anyone ever asking questions about transporting natural gas, gasoline, diesel, jet fuel, or coal within the United States. If there’s an oil spill somewhere in the ocean, or if offshore drilling comes up in the news, then people talk about local effects of a spill, but rarely about the national or international transport of oil.

  There are two key points here. First, all forms of energy have to arrive at the place where we want to use them or can use them. (We can sometimes go to the source of the energy, as do farmers taking their grain to a medieval watermill.)

  Second, energy can be converted into forms that are more easily transported, although the conversion always entails some loss. With the invention of the fuel cell, the conversion of electrical energy and chemical fuels became practical for many modern technological applications. An electric current passed through water separates H2O into hydrogen and oxygen. Although hydrogen is highly explosive and therefore hard to package, it is one of the best fuels. It can be combined with carbon to make methane, the simplest hydrocarbon (one carbon atom combined with four hydrogen atoms). Add an oxygen atom to methane in the right way and you have ethanol, alcohol that can power your car. In this way, the energy from sunlight, first converted to electricity, is transferred as energy stored in a gas or liquid fuel.

  The processes can also go the other, more familiar way—as many power plants do all the time, and as those convenient little home generators do: Use gasoline, diesel, oil, natural gas, or coal to run an electric generator, converting the energy stored in those gas and liquid fuels to AC or DC.

  Each form of energy that we use to power our civilization has a transportation network. The networks are huge, and as the accompanying illustrations show, each network is surprisingly complex (Figure 10.2).

  Figure 10.2 Oil pipelines in the United States: (Top) The big trunk lines.4 (Bottom) The smaller refined-oil lines.5 (Allegro Energy Group)

  The U.S. petroleum pipeline

  For petroleum alone, there are 55,000 miles of main “trunk” pipelines and 30,000–40,000 miles of smaller “gathering” pipelines in the United States, including both underground and aboveground pipes.6 Petroleum accounts for about 17% of all freight moved in the United States, and the pipelines carry about two-thirds of all that petroleum.7 It’s hard to imagine how much petroleum is transported—it’s another of those giant numbers that populate discussions of energy—but let’s try to picture it. According to one analysis, it simply couldn’t be done by truck or train. “Transport for high volume/long distance shipments are so daunting as to be impractical. Assuming each truck holds 200 barrels (8,400 gallons) and can travel 500 miles per day, it would take a fleet of 3,000 trucks, with one truck arriving and unloading every 2 minutes, to replace a 150,000-barrel per day, 1,000-mile pipeline.”8 And if all this were to go by rail, “Replacing the same 150,000-barrel per day pipeline with a unit train of 2,000-barrel tank cars would require a 75-car train to arrive and be unloaded every day, again returning to the source empty, along separate tracks, to be refilled.”9

  Transporting natural gas

  Right now, 19% of electric power in the United States is produced by burning natural gas, and this is expected to increase to 23% by 2016. The natural gas used in the United States flows through 300,000 miles of major trunk lines and 1.9 million miles of smaller lines, including those that deliver gas to your house and to 69 million other users of this fuel (Figure 10.3). Some areas of the nation depend quite heavily on natural gas for electricity. Texas gets more than half of its electricity from natural-gas-powered plants. Florida, California, Arizona, and parts of the Northeast—areas with high populations—are also very dependent on natural gas for electricity. A disruption in the natural-gas transportation network therefore could affect both heating and electricity in a large part of the U.S.10 The North American Electric Reliability Corporation agrees, saying that “disruptions in the supply or delivery of natural gas could have a significant impact on the availability of electricity” and that some measures to provide protection against such events are in development. These include more storage units as well as “alternate pipelines, expanded dual fuel capability, fuel-conservation dispatching, and increased coordination with gas pipeline operators.”11

  Figure 10.3 Natural gas pipelines.12 (DOE/Energy Information Administration/Office of Oil & gas, Natural Gas Division, Gas Transportation Information System)

  Remarkably, the natural-gas delivery network has been one of the safest forms of transportation of any kind, with only 12 fatalities in one year, 2002, during which there were 42,000 deaths on highways and a total of 2,000 deaths from aviation, boats and ships, and railroads.13, 14 According to the American Gas Association, gas companies spend $7 billion a year to maintain these pipelines. Natural gas also travels in a liquefied state, which requires that the gas be highly compressed. This is the way it is also transported across oceans among nations, and it is much more controversial because of the risk of explosions and vulnerability to terrorism.

  Advantages and disadvantages of the pipeline system

  Like air travel, petroleum transportation has hubs and spokes. New York City is one of the major hubs for importing and transporting oil, as is otherwise little-known Cushing, Oklahoma, along with Chicago, Los Angeles, and several areas along the Louisiana-Texas coast. Oil spills are of particular concern for hubs with high resident populations.

  It is important to note that not all the U.S. states are connected to each other by pipelines for either oil nor gas. California has no pipeline from other states, and New England has no pipeline connection to the rest of the nation—fuel arrives there by barge. This means that a large portion of the U.S. population lives where the least expensive and most efficient oil-delivery system isn’t available.

  The good news: Although the amount of material moved is huge, the cost per barrel or gallon is low. For example, in 2001 it cost only about 2.5¢ per gallon to send gasoline from Texas to New Jersey through pipelines. The cost is much higher by train, truck, and even by barge, as is the amount of energy expended to move the fuel by those means.15 In case you were wondering, oil moves about 3 to 8 miles per hour in the pipelines, so it takes two to three weeks for oil to get from Houston to New York City. This lag might create supply problems in an emergency, an argument in favor of going the electricity route.

  Transporting electricity: the grid, the smart grid, or no grid?

  Going the electricity route—trying to obtain, transport, and use as much energy as possible in the form of electricity rather than using that energy to make gas, liquid, or solid fuels—has its own problems, as we saw in the book’s opening story about the great 2003 blackout. Let’s start with this simple fact: The world’s largest machine is the U.S. grid system. Actually, it’s three systems: an eastern grid that covers the eastern two-thirds of the United States and Ca
nada; the Electric Reliability Council of Texas, which covers Texas; and a western grid that takes care of the rest of the United States and Canada that has grid connections.

  In the U.S., the grid was originally developed only as an emergency fallback. It was built mostly in the 1930s through the 1950s to provide emergency power as needed and extend electricity to the smallest farms in the most rural areas. Today, the grid includes more than 700,000 miles of transmission lines16 and 250,000 substations and has become the primary way of transporting electrical energy. With about 60% of its equipment more than 25 years old, one of the few things on which most energy experts agree is that the electrical grid is badly outdated, likely to fail, and in need of both major repairs and technological updating. (This is true even taking into account that electrical machines tend to be longer-lived than many others, such as internal combustion engines.) Bill Richardson, Secretary of Energy in the Clinton administration, said the U.S. grid was “third-world.”17