Analog SFF, January-February 2007

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Analog SFF, January-February 2007 Page 23

by Dell Magazine Authors


  Corn, of course, isn't the only crop that can be converted to fuel. Biodiesel and “cellulostic” fuels, made from other plant sources, may hold greater promise. These include products made from switch grass and wood chips, as well as fuels made from plant oils.

  These products require less energy to produce, in part because the plants don't need as much fertilizer. Also, “cellulostic” fuels are made from cellulose, a portion of the plant that cannot be fermented into ethanol by conventional processes. Using it can substantially increase fuel yields.

  There's still the question, however, of how much of such fuels we can realistically make. Prakash estimates that at maximum, they can replace only 10 to 15 percent of gasoline usage. Daniel Kammen, another energy expert at UC Berkeley, is more optimistic. Currently, he says, enough biomass is being generated in timber growing, farming, and as urban waste to meet 10 percent of U.S. transportation needs. With a major commitment, he thinks it might be possible to replace all of the nation's oil with biofuels. Even with major improvements in automobile fuel economy, though, that would require putting an additional 100 million hectares into agricultural production (an area 2 1/2 times larger than the state of California)—nearly a one-third expansion in the nation's entire farming acreage. “It's doable,” Kammen says, “but it would take some rough choices."

  * * * *

  Alternative Energy

  Luckily, the crisis we're facing isn't an energy crisis, per se. We may run short on oil, but we still have plenty of sources of energy.

  Top of the list is natural gas, of which there is about twice as much (in energy units) as there is of oil. Coal is even more plentiful. After that, there are tar sands and oil shales (although there are serious questions whether the latter can ever be mined on an energy break-even basis). Another wild card is methane hydrate, a weird type of natural gas-containing ice that forms under cold, high pressure conditions, typically in the Arctic or deep beneath the sea. Nobody's quite sure how much there is or how to extract it, but it may be more than 100 times more plentiful than conventional natural gas.

  Currently, natural gas reserves stand at 180 trillion cubic meters: a 67-year supply at current usage rates. Coal stands at more than 900,000 megatons: a 160-year supply. But remember, usage of these is likely to increase (especially as we start running out of oil), and there's no reason not to expect each of them to face its own Hubbert's peak. For natural gas, Goodstein thinks that could happen in as little as a decade, and for coal, it will probably come well before 2100. Perhaps methane hydrates will save us for another century, but that's speculative.

  Furthermore, we need to remember that Westerners aren't the only ones who'll want all these things. In 2000, China and India used only one-sixteenth as much oil per capita as Americans did, says Amos Nur, a geophysics professor at Stanford University. Given their much larger populations, even a modest increase in their per capita usage would represent an enormous increase in worldwide demand.

  Nur fears incipient panic and possibly even an oil war as the U.S. and China seek to safeguard their own supplies.

  Goodstein predicts inflation, depression, and resource wars, if not over oil, then over natural gas, coal, or other fossil fuels. Deffeyes’ predictions aren't quite as bleak, though he does think the next few years might be unpleasant, as prices soar and people in the Third World starve for lack of affordable tractor fuel. But so long as we avoid a major war, he predicts that the fifteen-year time horizon will find us settling into new energy sources.

  What will this alternative-energy future look like?

  Obviously, alternative fossil fuels will play a big role in it. But all of these have the drawback that, like oil, they contribute to global warming. Many experts prefer nuclear power. And in the long run (unless we finally manage to master fusion), the future belongs to solar power and wind.

  If we desire, solar and wind can be harnessed for large-scale products. Pave over an area the size of Nevada with solar cells, and you could generate all the power the country needs. But it doesn't have to be done on such a monolithic scale. A significant fraction of the country is already built up, opening the door for putting solar collectors atop existing structures.

  California recently enacted a “million solar roof” initiative, funded by a 25-cent-per-month tax on utility bills. The goal is to install 3,000 megawatts of rooftop solar collectors in ten years (enough to power a city of 600,000), tripling that level in the next five years. People who generate excess power, this way or via windmills, can sell it back to the electrical grid. Rather than a future of enormous, centralized power plants, we may see one of dispersed electrical generation with lots of little (and literal) cottage industries. “We need to think of the grid as eBay, where everyone can buy and sell, and the utilities are the broker,” Kammen says.

  But there's a difference between an energy source and a convenient fuel. What electric power alone doesn't give us is a vehicle equivalent to what we've become accustomed to. Unless you weigh them down with enormous batteries, electric cars are low powered and have limited range. If you really want to drive long distances or reach the end of a freeway onramp at a speed that won't get you rear-ended, you need a more traditional type of fuel.

  To start with, though, there's a lot that can be done to improve even a high-mileage car's fuel economy. Gas/electric hybrids are a great innovation, with generators that convert the energy otherwise wasted in braking into usable power. The next step is to add extra batteries to these cars to create plug-in hybrids that can be topped off at home, the office, and the mall. Already, an organization called CalCars is at work on this project. “It's a cool technology,” says UC Berkeley's Farrell. “It displaces the fuel source for some of your travel from petroleum to whatever is supplying your electricity."

  An alternative fuel that has nothing to do with petroleum would also help. Currently there are two prospects (assuming that ethanol really is a dead end): hydrogen and methanol. Both provide ways of converting solar-generated electrical power into something portable.

  * * * *

  Hydrogen, Hype, and the Hindenburg

  “Hydrogen is the energy source of the future.” I've lost track of the number of times I've heard this. But unless we're going to scoop hydrogen out of the atmosphere of Jupiter and bring it back here to burn, it's nonsense. You can't drill a hydrogen well on Earth, because Earth's hydrogen is almost entirely bound chemically to other elements. That means that you have to make hydrogen fuel, by prying hydrogen loose from something else.

  There are three main ways to do this. One is by partially burning coal in the presence of water vapor. That gives you “synthetic gas,” a combination of hydrogen and carbon monoxide. Another is to “steam reform” natural gas by allowing it to react with high-temperature steam in the presence of a catalyst. Again, you get a mix of carbon monoxide and hydrogen. In both cases, you can increase the hydrogen yield via a second production step in which the carbon monoxide is reacted with additional steam, to produce hydrogen and carbon dioxide.

  But these processes simply generate hydrogen from fossil fuels. For a truly renewable source, you need electricity and water.

  As you probably remember from high school chemistry, you can generate hydrogen and oxygen by passing an electrical current through water. This takes more energy than you're going to get back out of the fuel, but that's not quite the same problem we had with ethanol. With ethanol, we were using tractor fuel, etc., to make fuel. Here we're converting electricity into fuel.[8]

  [Footnote 8: Hydrogen, incidentally, is a fuel that can be used in fuel cells to drive some extremely efficient motors. It's also extremely clean-burning, producing nothing but water and perhaps a few trace contaminants.]

  But hydrogen has some major disadvantages. The scariest, of course, is that it is highly flammable. Nobody wants their hydrogen-fueled roadster to go the way of the Hindenburg. (Although, it wasn't actually the hydrogen that was to blame for the Hindenburg fire. It was the zeppelin's
outer skin that initially burst into flame.) It's also hard to see a hydrogen flame, raising the prospect that when accidents do occur, people will be slow to recognize the danger.[9]

  [Footnote 9: On the other hand, burning hydrogen won't spread across the ground in a lake of fire, as with liquids like gasoline.]

  A bigger problem is storage and distribution. Hydrogen gas can't be stored in most existing containers or shipped via natural gas pipelines because it is comprised of extremely small molecules that would diffuse through their walls and be lost. Prakash estimates that the much-touted hydrogen economy would require $2 trillion to $3 trillion in pipeline upgrades. That creates a massive chicken-and-egg problem, Prakash says, because who's going to commit to hydrogen cars (except as toys) if there's no fuel-distribution infrastructure? And who's going to build pipelines until there are hydrogen cars?

  Hydrogen is also difficult to compress and store—so difficult, Prakash says, that you'd spend 30 to 40 percent of its energy simply to liquefy it. On top of that, it's bulky, even when liquefied. It would take three tanker trucks to ship enough hydrogen to replace one tanker truck's worth of gasoline. There are also concerns about the effect of hydrogen leaks on the Earth's ozone layer.

  Prakash prefers methanol, which is a liquid at room temperature. That allows it to be burned in existing engines and transported in existing pipelines with only minor changes.

  Methanol is an extremely simple molecule—its molecular formula is CH3OH. It used to be called wood alcohol or methyl alcohol, but those are terms that should be discouraged, Prakash says, for fear that people will think they can drink it. It's several times more toxic than gasoline, which might make siphoning by mouth a bad idea, but ecologically it's safer than gasoline because it's biodegradable. It also dissolves easily in water, so that a methanol spill will quickly be diluted to the point where it can readily degrade.[10] Methanol can also be used as a feedstock for the petrochemical industry, which currently uses six percent of the world's oil production.

  [Footnote 10: It's also possible to create methanol-powered fuel cells.]

  For all of these reasons, Prakash and two other USC chemists, spearheaded by Nobel laureate George Olah, see methanol as the fuel of the future. In the short run, they argue in their book Beyond Oil and Gas: The Methanol Economy, it can be made from natural gas. But the real dream lies in the long run, when nuclear or renewable electrical power can be harnessed to make it from carbon dioxide and water. This has the advantage not only of harnessing electricity to create a fuel that's a lot easier to store and ship than hydrogen, but of doing so with a gas that's widely considered to be a leading culprit in global warming. Prakash sees this as a way of “recycling” carbon dioxide the way nature does, rather than dumping it into the atmosphere or attempting to dispose of it by piping it into the deep ocean or underground.

  CO2 for methanol production, he adds, could either be scrubbed from the emissions of coal-burning power plants (while they're still in use) or extracted from the air, anywhere on the planet.

  Whether we go with hydrogen, methanol, coal gasification, or something else, though, the changeover can't take place overnight. If the fossil-fuel cornucopians are correct, that's no problem because there's plenty of time for a slow, orderly transition. What has the Hubbertists concerned is that we've already spent too long sitting on our hands, rather than planning ahead.

  Goodstein thinks that the future of civilization as we know it hinges on making the right choice and doing it soon. “We understand the basic scientific principles for a civilization that runs without fossil fuel,” he says, “but we lack the political leadership and the will to do the job."

  My own view is a bit more optimistic. I'm convinced of the basic Hubbertian premise that the peak comes long before we “officially” run out. But my Ph.D. is in economics, not geology. That gives me greater faith in the market to slow the rate of decline. What I fear is that people won't believe that the halcyon days are coming to an end and that complaints about price gouging will lead to political pressure for price freezes. To an economist, that translates to mile-long gas lines and no real incentive for producers to find alternatives: in short, the worst of all worlds.

  I'm also a science-fiction writer, which means that I'm not that afraid of the demise of civilization as we know it. I can envision lots of changes that won't be all that catastrophic:

  —Telecommuting, telepresence, and VR waldos

  —Amtrak

  —Bike lanes on freeways

  —No more cheap FedEx

  —More online retail (though not with overnight delivery)

  —Soaring real estate prices near mass-transit hubs

  —Fortunes made (and lost) in alternative energy stocks

  —No more strawberries in January[11]

  [Footnote 11: I got this one from Deffeyes, who predicts that we're going to have to wean ourselves from air-freighted produce.]

  —Neighborhood shopping districts

  —Wool blankets and sweaters

  —Air-conditioning as a luxury, not a necessity

  —Two-minute showers

  —Saudi Arabia as an enormous energy producer ... of solar power[12]

  [Footnote 12: I got this one from Goodstein's book.]

  —Superconducting, undersea power lines to shuttle solar power from sunlit regions to the dark side of the globe.

  Are these the end of civilization, or just changes? I suppose that depends on what's critical to you. Me, I have an air-conditioner, but almost never turn it on. I've learned that even 90° isn't all that bad if you let the changing seasons acclimate you first to 75°, then to 80°, and then to 85°. And I'd do a lot more bicycle trips, too, if only the cars would get out of the way. A lot of folks think I'm kind of weird, but then, that's what they've always thought of us in science fiction.

  Maybe the end of civilization as “we” know it actually belongs to those of us in science fiction.

  Copyright © 2006 Richard A. Lovett

  * * * *

  About the Author:

  Richard A. Lovett is a frequent contributor to Analog, and one of the few joint members of the Science Fiction and Fantasy Writers of America and the National Association of Science Writers. Writing is his day job, mostly for National Geographic News, the San-Diego Union-Tribune, Running Times, and Psychology Today. If that sounds a bit eclectic, it is; he has degrees in astrophysics, economics, and law. His Ph.D. is in the economics of natural resources.

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  * * *

  Double Helix, Downward Gyre

  by Carl Frederick

  On a historic scale, everything changes, and new kinds of knowledge accelerate the process. The hard part is deciding when—and how—to react.

  It seems to get worse every day.” Herrick pointed a butter knife toward his son. “I wouldn't be surprised if, before long, the only fundable science left was Creation Science."

  “Oh, it's not that bad, Dad.” Niels hoped he could head off another angry rant; it was not good for his father's blood pressure. “I expect Congress—"

  “Congress!” Herrick gave a harsh laugh. “As a whole, they're as dumb as a Kansas school board."

  Niels made shushing motions. “Not so loud,” he said in a voice a little above a whisper. “It's not safe talking like that these days."

  Herrick glanced around the restaurant. “We're safe here, I imagine. Technically, this is New Zealand territory.” He returned his gaze to Niels. “I think it is, anyway."

  They sat at a table at Maori's—a trendy Pacific Rim cuisine restaurant attached to the New Zealand mission to the United Nations.

  Mission restaurants for the poorer countries were a source of revenue, but for wealthier countries, those with a declining birth rate, they acted as a lure to recruit immigrants. Herrick and Niels, for their weekly father/son dinners, had eaten their way through many of them. But then, acting on a recommendation, they tried Maori's. They liked the food, had no feelings of il
l will toward New Zealand, and so settled on Maori's for their weekly culinary excursion.

  Herrick grimaced. “This can't go on,” he said, pushing away his half-eaten dessert, a chocolate-topped Pavlova. “Soon it'll be impossible to do any scientific research at all in this country."

  Worried by the grimace, Niels watched as his father surreptitiously moved a hand over his stomach.

  “And it doesn't help,” Herrick went on, “that our government seems to mark top secret every scrap of paper down to and including toilet paper."

  “Indigestion again?” Niels tried to keep the worry out of his voice.

  Herrick shrugged, then gave a smile, clearly labored. “And there's no money for physics anymore.” He pointed, this time with his forefinger. “It's good you're in medical research; aging politicians need you."

  Niels knew his father was trying to move the topic away from his indigestion, and Niels, for the moment, would let him. “Actually, they don't seem to need me.” Niels said. “In fact, I've been denied tenure.” He looked down at his hands. “Great way to end the academic year,” he added under his breath.

  “What?” Herrick sat back from the table as if struck. “No! I can't believe my alma mater would act that way. Not Yale."

  Niels forced a smile. “Some wealthy alum objected to my Evolutionary Biology course."

  “What are you going to do?"

  “Nothing.” Niels stirred his coffee, even though he drank it black. “As long as I don't make a stink about it, the university will simply ignore the situation.” For the sake of his father, he tried to downplay the insult. “My teaching and research won't be affected. I just won't be tenured. No big deal."

  Niels saw his father bite down and, almost as if in reflex, move his hand toward his stomach and then abruptly change direction and pick up his teacup.

 

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