Power Trip: From Oil Wells to Solar Cells – Our Ride to the Renewable Future. Amanda Little

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СКАЧАТЬ any directional shifts. The rig’s electrical system is also highly vulnerable—if a fuse blew, the thrusters would seize up, and the drill shaft would have to be severed. Still another challenge is guiding the drill on its optimal course down through 30,000 feet of sediment—a challenge akin to “flying above New York City in a jumbo jet, aiming a baseball at the pitcher’s mound in Yankee Stadium, and hitting it dead center,” said Siegele. The margin of error as the drill enters the seafloor is only about a meter in any direction. Any farther, and chances go up that you’ll hit a fault line or air pocket that will throw the whole well off.

      Charting the course of the drill is an implausibly difficult task of its own. “We’re pretty much shooting in the dark,” said Siegele. Chevron runs its offshore drilling operations out of a gleaming Houston skyscraper that’s the shape of twin cylinders, resembling the nose of a double-barreled shotgun aimed skyward. The company devotes billions of dollars annually to mapping out the subsea landscape of its deepwater fields on high-tech equipment at this location, but there’s a limit to what these maps can show.

      Geologists work in cavernous visualization rooms with floor-to-ceiling monitors and computers that have the processing power of “a PlayStation the size of an eighteen-wheeler,” as one engineer described it to me. The computers crunch seismic data that are then translated into maps of ancient sediment. To collect the data, geologists deploy ships that cruise above deep-sea prospects and pop off air guns—underwater cannons that emit gigantic burps of air into the ocean, bouncing sound waves off the underwater rock formations. Aquatic microphones tethered to the vessel record the response.

      Gathering seismic data for subsea oilfields in the Gulf of Mexico is far trickier than in other offshore drilling regions. The sediment beneath the Gulf has a salt layer that’s as massive and ragged as the Swiss Alps; this layer acts like a fun house mirror for sound waves, deflecting and distorting them in ways that other sediments don’t. So Siegele’s team had to trigger multiple air guns at once while microphones took hundreds of thousands of recordings simultaneously. The vast constellation of data points enabled Chevron’s seismologists to unscramble the salt layer’s distortions. Still, the maps were largely inscrutable. “Reading these maps is like looking through a wall of thick glass brick,” as one geologist told me, “and trying to count the eyelashes of a person on the other side.”

      The maps also can’t predict how hard it will be to extract the crude. You might think of oil as situated in big pools under layers of rock. But it’s actually embedded in the rock, like water in a sponge. “When you drive the drill down you’re going into porous rock that can be either kind of squishy or kind of rigid,” Siegele explained. Squishy is better, but as rocks age in deeper terrain, they typically become tighter—meaning less productive. You also confront more debris that can clog the well shaft: in other words, instead of sucking up the oil in one big swig like a soft milkshake, it’s as though chunks of ice and strawberry get stuck in the straw. That’s why, when I visited the Cajun, teams of geologists were standing by to analyze the rocks and mud that got pulled up by the junk basket, hoping to gather a better understanding of the conditions deep below.

      Temperature and pressure also pose risks to drilling activities, so engineers must vigilantly scan the computer readouts that monitor these conditions as machinery travels down through the sediment, crossing geological layers that range from hard bedrock to sand to empty voids. The rapid pressure changes between these layers routinely disturb equipment. At the well bottom, there is enough pressure to implode a human head—or more pertinently, to crack iron casings. And the closer you get to the earth’s core, the hotter the rocks become. At 20,000 feet below seabed, the oil is hot enough to boil an egg. At 30,000 feet, the oil can reach over 400 degrees Fahrenheit, hot enough to cook off into natural gas or carbon dioxide. Meanwhile, the water at the bottom of the deep sea is at near freezing temperatures, creating a dangerous contrast as the oil is pulled up.

      Any one of these factors—loop currents, faulty drill placement, electrical glitches, rock porosity, pressure and temperature changes—could delay operations for days, weeks, even months. At more than half a million dollars a day, the operating costs add up on deep-sea rigs like the Cajun. Hurricanes, too, pose an ominous threat. In 2005, the year of Katrina, Chevron had to carry out seven emergency evacuations. BP’s legendary Gulf of Mexico platform Thunder Horse suffered a $250 million blow when a hurricane tore a tiny hole in its hull that eventually sank half the rig, requiring a stem-to-stern reconstruction.

      FINAL FRONTIER

      Given the challenges that plague ultradeep drilling, it’s sobering to think that this frontier holds the oil industry’s best hope for finding new petroleum reserves. “The odds are incredibly low that we’re going to hit some fabulous new discovery on land,” Matthew Simmons, a leading investor and industry analyst, told me. “Everybody’s looking to the deep sea for big new finds.” To an outsider, it was at once impressive and baffling to watch engineers burrow 5 miles into the earth for oil. “It has all the audacity and technological complexity of launching a space shuttle,” as Simmons put it. I found the enterprise doggedly ambitious, but also seemingly desperate—like an addict forcing a syringe into the earth’s innermost veins.

      Siegele himself admitted that “there’s no guarantee that the rewards in this field will outweigh the risks.” After my visit, in fact, an even greater snag than the one I’d witnessed occurred on the Tahiti field’s production platform: an incorrectly soldered mooring would cause a year-long setback that cost Chevron over a hundred million dollars, by a conservative estimate. But the sunken treasure was worth it: the company proceeded with repairs despite the high cost and began to pump oil from that platform by mid-2009.

      One question persisted in my mind: if an energy company is going to throw a billion dollars into something untested and possibly doomed to failure, wouldn’t it make more sense to invest in the inexhaustible, greener technologies that will likely replace fossil fuels? None of the Chevron employees I spoke with seemed concerned that their industry may be fast approaching obsolescence. “Do you heat your home? Do you fly on planes? Do you drive a car?” Siegele challenged me. “What do you think makes that heat and moves those jets?”

      Siegele was right. Even as innovators have been producing breakthroughs in clean cars, green buildings, and renewable energy and efficiency, the Department of Energy projects that American oil demand will hold steady—not decline—in the decades ahead. American oil demand on the whole has been holding steady in recent years, not declining. And even if America were to slash its oil consumption, industrial growth in China and India is pushing global petroleum demand ever higher. The New York Times has reported that the global demand for energy could triple by midcentury. “So long as people need oil,” Siegele told me, “we’ll find a way to supply it.” In other words, the oil industry will go to whatever lengths (literally and otherwise) it must to get oil so long as consumer demand persists and the oil is there for the taking.

      But how much oil is there for the taking, and how long will supplies last? It depends on who you ask. The moment when the global economy reaches “peak oil” will be the most significant tipping point of the twenty-first century—the point in time when the world’s oil producers can no longer increase their supply, and the industry enters “terminal decline.” Though “peak oil” is a confusing term, it can be pictured simply as the peak or high point on a graph of production over time. It doesn’t mean that we’ve run out. It means that the world’s oil fields will be producing less and less each year. After this peak, the falling-off of oil supplies will in turn bear directly on the basic demand-supply curve of Economics 101: when supply declines and demand stays steady (or rises), prices will rise. A mere 4 percent shortfall in oil production, for instance, could lead to a 177 percent increase in the price of oil.

      It’s true that oil could stay cheap if demand dropped faster than supply. We saw that happen recently, as the economy slumped in 2008. Industrial activity slowed, curbing the flow of fuel into СКАЧАТЬ