ONE
THE LOST BOOK OF THORIUM POWER
Kirk Sorensen was a rookie engineer at the Marshall Space Flight Center in Huntsville, Alabama, when he stumbled on the book that would change his life. This was in 2000. Sorensen was part of a team of engineers and physicists studying ways to use nuclear energy to power rockets to carry cargo into space. It was, as engineers like to say, a multivariable problem: the scientists had to consider the weight of the launch vehicle, tight confines of the engine compartment, extremes of temperature and atmospheric pressure as the rocket ascended beyond the atmosphere, risk of catastrophic accident, and so on. They quickly realized that conventional nuclear reactors would not do the job. And so they began looking into alternative reactor designs.
One afternoon that spring, Sorensen stopped by the office of his older colleague, Bruce Patton, a long-time nuclear engineer on assignment at the Marshall Center from Oak Ridge National Laboratory in Tennessee. Patton, who had lived through many changes of administration and many dead-end research programs at the national lab, had taken a liking to the young Mormon from Utah with a linebacker’s build, a rocket scientist’s intellect, and the temperament of a cattle-dog puppy.
Sorensen leaned against the door frame, his bulk filling the opening. The offices of chief scientists at Oak Ridge are not large, and Patton was not a chief. As technologists do, they chatted for a while in a language foreign to nonspecialists—Sorensen recalls it was about his growing frustration with the search for inexpensive ways to get heavy payloads into orbit. On the bookshelf in Patton’s office he noticed a book with an intriguing title: Fluid Fuel Reactors. He picked it up and started leafing through it.
It was a book only an engineer could love. Published by the Atomic Energy Commission in 1958, during the Atoms for Peace era under President Dwight D. Eisenhower, and written by a group of contributors under the editorship of the Oak Ridge scientist James Lane, it ran 945 chart- and graph-crammed pages and weighed in at a biblical three pounds. Featuring chapter titles like “Integrity of Metals in Homogeneous Reactor Media” and “Chemical Aspects of Molten Fluoride Salt Reactor Fuels,” Fluid Fuel Reactors details the work carried out in the 1950s at Oak Ridge, under then-director Alvin Weinberg. It describes nuclear power reactors with cores that were liquid, not solid, and that offered some intriguing advantages over the conventional light-water reactors (cooled by ordinary water) that make up nearly 90 percent of the reactors in operation today. It also describes the use of a novel nuclear fuel, an alternative to uranium and plutonium: the radioactive element thorium.
Sorensen took the book home and devoured it within days. His sleep suffered. A devout Mormon and a linear-thinking engineer, Kirk Sorensen was an unlikely revolutionary. But Fluid Fuel Reactors dropped a lit match into the dry tinder of his mind.
Here, he realized, was a potential solution—not to the problem of nuclear-powered spaceflight, which he had by that time decided was a pipe dream anyway, but to society’s insatiable thirst for energy. Like most engineers of his generation, he knew that thorium is an actinide—one of the heavy elements on the bottom row of the periodic table of elements, a group that includes uranium and plutonium—and he vaguely remembered that the United States had done some work on thorium reactors in the two decades after World War II.
That work had gone far beyond calculations and experiments to an actual working reactor, and a sizable contingent of scientists, including Weinberg, believed that thorium-fueled reactors, with fluid cores of molten salt, should have been the future of nuclear energy. Outraged, Sorensen asked himself the question that has become a persistent refrain among thorium advocates: Why has this never been pursued?
Thorium is around four times as abundant as uranium and about as common as lead. Pick up a handful of soil at your local park or ball-field; it contains about 12 parts per million of thorium. The United States has about 440,000 tons of thorium reserves, according to the Nuclear Energy Agency; Australia has the world’s largest resources, at about 539,000 tons. Like uranium and plutonium, thorium makes a dense and highly efficient energy source: scoop up a few ounces of sand on certain beaches on the coast of India, it’s said, and you’ll have enough thorium to power Mumbai for a year.
Used properly, thorium is also far safer and cleaner than uranium. Thorium’s half-life, the time it takes for half of the atoms in any sample to disintegrate, is roughly 14.05 billion years, slightly more than the age of the universe; the half-life of uranium is 4.07 billion years. The longer the half-life, the lower the radioactivity and the lower the danger of exposure from radiation. Thorium’s rate of decay is so slow that it can almost be considered stable; it’s not fissile (able to sustain a nuclear chain reaction on its own), but it is fertile, meaning that it can be converted into a fissile isotope of uranium, U-233, through neutron capture, also known as “breeding.” You can’t mash together two lumps of thorium, even highly purified thorium, and trigger a nuclear explosion. Left alone, a chunk of thorium is no more harmful than a bar of soap. In fact, for a period before World War II, a thorium-laced toothpaste was marketed in Germany under the brand name “Doramad.” Because of its unusually long decay process and its rare ability to breed through neutron capture, thorium is a more energy dense and efficient source of energy than uranium or plutonium: As a nuclear fuel, thorium reserves carry enough energy to power humanity’s machines for many millennia into the future.
Thorium advocates point out that it’s impossible to make a bomb from thorium, and significantly more difficult to make a bomb from uranium bred in thorium reactors than from enriched natural uranium. U-233 bred from thorium includes other undesirable isotopes, namely uranium–232, that provide built-in proliferation resistance. Nuclear waste from the thorium fuel cycle is also less hazardous to future generations. Fluid-fueled reactors known as liquid fluoride thorium reactors (LFTRs, pronounced lifters) can act as breeders, producing as much fuel as they consume. In LFTRs, thorium offers what nuclear reactor designers call higher burnup—there’s less of it in terms of volume and less long-lived radioactive wastes to deal with afterward than uranium. They can even consume highly enriched fissile material from dismantled warheads and long-lived transuranics in spent fuel from other reactors, turning it into a relatively benign and shorter-lived form of spent fuel, thus eliminating the need for geologic storage for thousands of years. What’s more, LFTRs are inherently safe: The fission reactions occur in a radioactive cocktail of molten salt containing uranium-233 and jacketed by a blanket of thorium for breeding, requiring only a small start-up charge of enriched uranium, with thorium as the sole input thereafter. As the liquid fuel in the core heats up, it expands, decreasing the amount of fuel available, slowing the rate of fission reactions and cooling the fuel. It’s like doubling the size of a pool table while keeping the number of balls on the table the same: fewer collisions occur, resulting in an extremely stable and responsive operation. The reactor core in a LFTR includes a “freeze plug” of frozen salt at the bottom, like the plug in a bathtub drain. Any power outage or unexpected deviation causes the freeze plug to melt, and allows the fuel in the core to drain into a shielded container designed to withstand the residual heat from the decay of fission products in the fuel. Because the reactor is inherently stable and the liquid fuel can be readily drained from the reactor core, a meltdown is physically impossible.
In the thorium fuel cycle, thorium bombarded by thermal neutrons transmutes over a period of time to uranium-233, which is capable of sustaining a fission reaction. This process has multiple advantages over the fission process in a conventional reactor using uranium-235. (Brad Nielsen)
Thorium could provide a clean and effectively limitless source of power while allaying all public concerns—weapons proliferation, radioactive pollution, toxic waste, and fuel that is both costly and complicated to process. These concerns have crippled the nuclear power industry since the early 1980s.
Today, with global warming accelerating, climate-neutral nuclear power is poised for a worldwide comeback commonly referred to as the nuclear renaissance. At the same time, it’s clear that the flaws of conventional, uranium-based nuclear power—which accounts for no more than one-fifth of power generation in the United States and less than that worldwide—make it an unsuitable replacement for fossil fuels in the near term. The nuclear accident that followed the earthquake and tsunami in Japan in March 2011 caused many countries to reconsider their ambitious nuclear agendas.
The problem is that only by shifting to non–carbon-emitting energy sources, like nuclear power, will we avoid catastrophic global climate change. Outside of the right wing of the Republican Party, hardly anyone today questions the worldwide scientific consensus that human-caused global warming, if left unchecked, will result in disruptions of a civilization-threatening nature: coastal cities like Calcutta and Miami inundated by seawater, huge swathes of farmland desertified, many now-populated areas uninhabitable, prolonged drought, and so on.
According to the International Energy Agency, worldwide demand for energy will rise by nearly 40 percent by 2035—a figure that many analysts, citing booming economic growth in the booming nations of China, India, and Brazil, consider low. Meeting that demand with current energy technologies would result in the addition of many billions of tons of carbon into Earth’s atmosphere—and, most likely, in resource wars, famine, and the effective collapse of functioning society in many regions. The fossil fuel society on which we have built our civilization is simply no longer tenable.
Many well-meaning observers argue that by shifting to renewable sources, like wind and solar, and reducing energy demand through conservation and increased efficiency, we can shift away from fossil fuels in time to avert this disastrous scenario. Unfortunately, those hopes are illusory.
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I FIRST MET KIRK SORENSEN in early 2009, when I was researching a feature for Wired magazine on the thorium power movement. I’d been covering energy for the better part of two decades. Since 2002 I’d been based in Boulder, Colorado, and had gotten a close-up view of both the natural gas boom that took hold in the northern Rockies in the first decade of the new century and the renewables push crystallized by Colorado’s new governor, Democrat Bill Ritter. Like many of my generation, I had a deep foreboding about what rampant use of fossil fuels was doing to our planet and a conflicted attitude toward nuclear power.
I also had one overriding belief: A new technology that promises to improve life or provide people with new goods or make things less expensive cannot be stopped. You can delay it, regulate it, boycott it, or ban it, but eventually the technology will triumph.
I first read about thorium in a blog post by Charles Barton Jr., the son of one of the scientists who’d collaborated on experiments with thorium-based molten salt reactors in the 1960s. The blog ran on The Oil Drum, a “peak-oil” blog that examines the consequences of dwindling fossil fuel resources. At the same time, I was researching a report for Pike Research, a clean-tech energy research firm based in Boulder, on carbon capture and sequestration (CCS). CCS has been touted in some quarters as the answer to the evils of coal-fired power plants, which are by far the largest emitters of carbon per unit of power provided by any electricity source. Governments, including that of the United States, are pouring billions into developing systems that will separate the carbon from coal plant smokestack emissions (the capture) and then bury it permanently in underground reservoirs (sequestration). As I got deeper into the research, it became more and more clear that the numbers just didn’t add up: CCS is an unproven, hugely expensive technology that is unlikely to be adopted at commercially significant levels in anything close to the time frames predicted by its supporters.
“Many of the current goals and targets for emissions captured between now and 2030 are overly optimistic,” I wrote. This was a conclusion that was bolstered by studies from MIT, Stanford’s Program for Energy and Sustainable Development, and Harvard’s Belfer Center, among others.
Unfortunately, the same is true of many projections for renewable energy—especially solar and wind power. In the same period, I was doing some reporting for a website called Energy Tribune, run by Robert Bryce. A conservative journalist and energy analyst, Bryce has become one of the principal skeptics of green energy. I already had doubts about whether the glowing predictions for wind, solar, biofuels, and other forms of green energy could fulfill their promise in time to limit catastrophic global warming in my lifetime or that of my son, born in 1999. Bryce’s work cemented those doubts.
In two books, Gusher of Lies (2008) and Power Hungry (2010), Bryce convincingly demonstrates that placing our faith in renewables, as that term is conventionally understood, is a “dangerous delusion.” “The deluge of feel-good chatter about ‘green’ energy has bamboozled the American public and U.S. politicians into believing that we can easily quit using hydrocarbons and move on to something else that’s cleaner, greener, and, in theory, cheaper.”1
In fact, there is only one way to transition from an energy economy based largely on fossil fuels to a sustainable “New Energy Economy,” as politicians like Colorado’s Ritter like to call it: moving quickly to what Bryce calls N2N, a combination of natural gas and nuclear power for production of baseload electricity. (Baseload is the minimum amount of electricity that a power company must consistently generate to meet the demands of its business and residential customers.) In the liberal green circles in which I moved in Boulder, this amounted to right-wing heresy. But, while I didn’t agree with some of Bryce’s harder conclusions (“MYTH: Wind Power Reduces CO2 Emissions”), the numbers were unassailable.
To take one example, the International Energy Agency has projected that new nuclear power plants will produce electricity for approximately $72 per megawatt-hour (one hour of operation at a rate of one megawatt). Electricity from onshore wind farms will cost up to $94 per megawatt-hour.
What’s more, to build enough wind, solar, and other renewable energy projects to significantly reduce coal and oil use would require time and resources we simply do not have. In considering the real costs of different energy sources, it’s important to take into account not just construction and operating costs but secondary factors like transmission, road building, resource extraction (of petroleum, coal, uranium, and so on), and real estate. Way back in the late 1970s, I took a course at Yale called “The Physics of Energy.” The first assignment was to calculate how big a solar plant, in an ideal sun-drenched location like the American Southwest, would be required to supply 90 percent of U.S. electricity demand at the time. I’ll spare you the calculations, but the answer was “roughly the size of the state of Arizona.”
“Renewable sources such as wind and solar . . . require hundreds—or thousands—of square miles of land for power generation,” Bryce noted. “The same problems of energy sprawl hamper the development of hydro-power and biofuels.”2
To give one more example, the local utility in Austin, Texas, where I spent a year in graduate school, announced in early 2009—just as I was becoming fascinated by the thorium movement—that it would spend $180 million on a 30-megawatt solar plant. Officials said the new sun farm would run at an average 23 percent of capacity, producing power at a construction cost of $6,000 per kilowatt of capacity. “Thus, Austin Energy has agreed to build a solar plant that will operate about one-fourth as often as a nuclear plant and cost about 25 percent more on a per-kilowatt basis,” Bryce scoffed.3
And these power sources must be compared with uranium and thorium, the densest energy sources on the planet, which can produce power from room-sized reactors. Nuclear power came with its own costs, to be sure— costs that have been dismissed by the nuclear power industry—but, like Bryce and a growing number of green-energy supporters, I came to believe that wind and solar alone cannot help us escape from our current predicament. Only nuclear can. And only thorium can produce nuclear power that is environmentally safe, is economically competitive, and does not lead to the proliferation of atomic weapons.
For all those reasons, a critical mass of government funding, private-sector investment, and new research and development has begun to coalesce around the idea of returning thorium to its rightful place as a primary source of energy for the twenty-first century. Recently several countries, including the waking giants India and China, have announced or confirmed plans to build thorium power reactors, and R&D programs for thorium have sprung up at universities across Europe, Asia, and North America. Even U.S. policy makers have started to promote thorium power: several bills have been introduced to fund thorium R&D programs at the Department of Energy, and respected experts on climate change, such as the NASA scientist James Hansen, have spoken out in favor of thorium power. Thorium could transform not only the nuclear power industry but our entire energy economy, liberating us from dwindling oil supplies and poison-spewing coal plants. It could fuel the energy revolution the world desperately needs.
And Kirk Sorensen, in a modest engineer kind of way, has become the Lenin of this revolution.
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WHEN I FIRST MET HIM, in the spring of 2009, Sorensen was a grad student in the University of Tennessee’s storied nuclear engineering program and an obscure scientist on a NASA program that even its own researchers considered far-fetched. Two years later he was the chief nuclear technologist at Teledyne Brown Engineering, the aerospace, defense, and nuclear power arm of giant Teledyne Technologies, and he’d been officially assigned by Teledyne Brown’s CEO, Rex Geveden, to build a thorium reactor.
In a small way I’d contributed to his rise. The story on thorium power I wrote for Wired magazine, which ran in December 2009 and featured Sorensen prominently, had made an impression on Geveden. “He said he read your story and in the margin he wrote ‘Hire this guy,’” Sorensen told me later. By this time Sorensen had also become the unofficial general of the thorium power army, speaking frequently at conferences (including a couple of appearances at the Googleplex, the Silicon Valley headquarters of the search engine giant Google), and running the Energy from Thorium blog, which by early 2011 was getting about sixty thousand visitors a month. It is home to a discussion forum in which participants debate the finer points of nuclear arcana such Hastelloy-N, neutron flux, and the drawing-off of xenon gas. Sorensen was 35, and as I got to know him better I realized that the story of a man’s life that pivots on the discovery of a book is central to his family’s history.
He was born in Bountiful, Utah, and raised in Farmington, north of Salt Lake City, in the farmlands along the eastern shore of the Great Salt Lake. His ancestors, Danish Lutherans who converted to Mormonism, had settled the area more than a century before. Mormon missionaries had arrived in Denmark in the 1850s, and the new religion took hold in the minds of Kirk’s great-great-grandfather, Isaac Sorensen, and Isaac’s brother Abraham. Equipped with a copy of the Book of Mormon, the brothers convinced their extended family to join the young church and to make the long journey to Zion—that is, the unsettled frontier on the far side of the Rocky Mountains, in the New World.
“The time arrived for our leaving old Babylon, we took leave from the old homestead where father had dwelt 27 years and raised a family of twelve children,” Isaac recalled, “ten alive, two dead.”4
Approximately seventeen thousand people eventually left Denmark to settle in what became in 1896 the state of Utah. At one time Danish accents were heard among a significant proportion of the total Mormon population in the West. Most became farmers, but plenty also became builders. Isaac’s great-grandson Keith, Kirk’s father, spent his career working on big construction projects in Utah, including the massive pumps on the Great Salt Lake, and the Delta Center, where the Utah Jazz of the NBA play.
Kirk attended Utah State University (USU) to study mechanical engineering. Like most Mormons, he took a couple of years off from college to go on mission, proselytizing door to door like the missionaries who’d converted his great-great-grandfather. Sent to rough Texas towns like Palestine and Tyler, Kirk had less success. But Sorensen, a relentlessly glass-half-full guy, sees his missionary years as full of powerful lessons, if low on converts: “I got this incredibly concentrated life experience for two years—I had ten years of human contact in that time.”
When he returned from his mission, Sorensen finished his studies at USU under a former U.S. Air Force colonel who impressed on his student the need to push forward with the exploration of space. With his customary alacrity, Sorensen moved into aerospace engineering. He quickly realized that the central problem of space exploration was the expense of launching vehicles into orbit: “If you couldn’t lower the cost to put stuff in space, nothing else was going to matter.” NASA was funding the X-33 program, a research effort to design a reusable launch vehicle that could reach orbit in a single stage. “I determined in the spring of ’97 I was gonna get on this program,” Sorensen said. After tracking down the email address of the chief engineer for the program, Sorensen wangled himself an internship on the X–33 team, headquartered at the Lockheed Martin R&D lab in Palmdale, California.
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IT WAS A PIVOTAL POINT, a singularity, the first of several moments when his life took sudden right-angle turns. “Getting a job at Lockheed Martin was a bigger deal than my entire undergraduate education,” he told me.
The next pivotal point came during graduate school at Georgia Tech. While he was working on a NASA-funded program led by John Mankins, the space agency’s director of exploration systems research and technology, Sorensen was still studying reusable launch vehicles, now with the goal of putting massive solar arrays into space that would beam energy back to Earth by using microwaves. For an engineer Sorensen is a romantic. Like Conrad’s Lord Jim, Sorensen had “that faculty of beholding at a hint the face of his desire and the shape of his dream.” He read Stewart Brand’s Space Colonies. He read The High Frontier by Gerald O’Neill. He became “a full-on 100-percent believer” that humanity’s future lay in outer space. This was “the coolest crap in the world.” It was utopia, and it was why aerospace engineers like Sorensen had to lower the costs of getting stuff into orbit.
Then, as I’d done with carbon capture, he tried to make the numbers work. He and his Georgia Tech colleagues spent months trying to “close the model,” to work out a set of cost-benefit equations that would make space-based solar power economically feasible. How low would the cost of the rockets, and of the launch, have to be to make the business model realistic?
“We were continually trying to crank the launch cost lower and lower to get the model to close,” Sorensen recalled. “We were modeling this incredibly dystopian future where a kilowatt-hour cost 25 cents, there was a carbon tax on everything, but we had perfect microwave beaming, and incredible solar arrays—every favorable factor for space-based solar.”
Still, the numbers wouldn’t crunch. “Finally I was sitting with my buddy and I said, ‘Type zero into the launch model. How good is it at zero?’ That meant, you snap your fingers and it’s up there. He typed zero into the model and it still didn’t close. We still couldn’t make this thing work.”
It was the first big disillusionment of Sorensen’s young career. “I looked at him and said, ‘Why are we working on this? This is a dodge. It’s basically crap.’”
It was the end of his scientific innocence, of believing in a utopian energy future in which a career in space science was going to lead to a bright future for humanity. Sorensen’s search, however, had only begun. He could not shake the idea that somewhere out there was a source of clean, inexpensive, limitless power, if only he could find the right technology. Next up was nuclear fusion.
At Georgia Tech he took a class with Weston Stacey, the author of several books on nuclear fusion and one of the many scientists who have basically spent their careers chasing the chimera of producing energy by crashing atoms together rather than splitting them apart. This time it took only a few months of study, rather than years, for Sorensen to conclude that he’d capture a live unicorn before he’d build a working fusion reactor.
“The more I learned, the more I was, like, ‘You’ve got to be kidding— why on earth would anybody think this is going to make economic sense?’” He realized that, at its core, a fusion reactor relies on a giant superconducting magnet that literally wants to rip itself apart. In the old engineer’s joke fusion is a technology that’s 20 years off—and has been 20 years off for 50 years.
Like a man trying and rejecting belief systems, Sorensen was checking off a mental list of potential energy panaceas: Space solar, no. Nuclear fusion, nope. Studying fusion, though, led him to become intrigued with its more feasible cousin, fission.
This was at the beginning of the twenty-first century, and conventional fission-based nuclear power was seen, especially at places like Georgia Tech, as an old-school, unsafe technology that had had its moment and blown it. The nuclear industry in the United States was essentially dormant; no new reactors had been built for almost two decades, and few bright, ambitious technologists wanted to go into the field. Sorensen, though, became more and more intrigued. Fusion was difficult to the point of impossibility, he realized. Fission is not.
Often referred to as splitting the atom, fission is the process by which an atom absorbs a stray particle and then, after a fleeting instant, splits into a new atom and flings off various particles, releasing a tremendous amount of energy in the process. It’s the transformation at the heart of the atomic bomb and of all nuclear reactors in operation today. Fusion works in the opposite way: two atoms combine, or fuse, releasing even more energy.
“The reason fusion is so hard is you’ve got charged particles, and they don’t want to get anywhere near each other,” Sorensen said. Overcoming those repulsive forces is incredibly difficult; just to get a tiny fraction to come close enough together to get a fusion reaction takes huge amounts of energy.
“Compare that with how easy fission is. A neutron doesn’t feel the charge of the electrons that orbit the atom—it just waltzes through like there’s nothing there. It doesn’t involve high temperatures or thick magnetic fields or superconducting magnets or any of that,” Sorensen said. “Fusion is so hard it takes teams of Ph.D.s and they’re still scratching their heads. Fission is so easy we hire high school grads to run nuclear submarines and they can do it.”
Sorensen, though, was an aerospace engineer by training, and he and his wife had a newborn. Switching careers at that point was hardly an option. So despite his misgivings about the future of space exploration, he took a job at NASA. Once again he found himself working long days to find inexpensive ways to get stuff into space. That’s when he walked into Bruce Patton’s office and found a copy of Fluid Fuel Reactors on the shelf.
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AS HE READ THE BOOK, Sorensen quickly knew that he’d reached another pivotal point, and the subsequent course of his life seems to him now to have been as surely determined as his great-great-grandfather’s was when he first held in his hand a copy of the Book of Mormon. Sorensen, though, claims the path was less straight. He’d been burned twice already by ideal-sounding solutions to the interlaced problems of insatiable energy demand and rising global temperatures; he would not be won over a third time quite so easily.
“I started thinking a lot about energy—what on earth are we going to do? When I started to learn about thorium, and about liquid fluoride reactors, I wondered, Why aren’t people doing this? But then I was very skeptical—I’d had two energy lovers already.”
First, he realized that, as an aerospace engineer reading a nuclear engineering text, he didn’t understand the terminology. So he began to teach himself the relevant physics and engineering, reading the most important texts—many of which were hopelessly out of date by the early twenty-first century and hadn’t been revised in decades—and following the discussions on websites like Atomic Insights. He read everything by Alvin Weinberg he could find, including the former Oak Ridge director’s 1994 memoir, The First Nuclear Era: The Life & Times of a Technological Fixer. As Sorensen sought to understand the debates about the looming energy crisis, he studied the politics and economics of climate change. And he came to realize that the full history of thorium power, and of fluid-fueled reactors, lay moldering in boxes in lab buildings at Oak Ridge.
By this time, early 2002, Sorensen and Patton had been assigned to another task, one that seemed even more far-fetched than space-based solar arrays: researching the feasibility of a manned spacecraft to Callisto, one of the moons of Jupiter. To get there at the speed of the fastest known spacecraft would take years and way too much fuel for the rocket to carry. The mission would clearly require some form of nuclear power. Thinking back to Weinberg’s work, Sorensen recalled the molten salt reactor experiment at Oak Ridge National Laboratory.
The Pentagon created Oak Ridge in 1942 in the hills outside Knoxville, Tennessee, and it served as one of three primary R&D centers for the Manhattan Project. It was, in many ways, the birthplace of both nuclear weapons and nuclear power. But the lab never did a perfect job of preserving its own history. Most of the history of the work done on the thorium fuel cycle and liquid-core reactors resided in dusty boxed archives, in reports and studies that had lain untouched since they were first produced and filed away. When Sorensen embarked on his quest to learn everything he could about liquid-core reactors, it was a rare moment when one man’s intellectual inclinations joined perfectly with the requirements of a large bureaucracy. Sorensen and Patton managed to slice $10,000 from the research funding for the Jupiter mission study ($150,000 or so) to pay to have the documents at Oak Ridge on molten salt reactors (MSRs) exhumed, dusted off, and scanned into digital form. At the time, Sorensen had no intention of starting a movement; he was just doing a thorough research job. Having the material on CD would be much, much easier than combing through all that paper.
The documents, most bound in heavy reports, were digitized during the next six months. No more money was available. Sorensen now estimates he has about two-thirds of the most interesting material from the archive. It shows a far greater depth of R&D on MSRs in the 1960s than Sorensen, or indeed most of the current generation of Oak Ridge scientists, realized. Sorensen began to understand what a treasure he’d unearthed. Then, a few months later, history crashed down around the Marshall Space Flight Center.
On February 1, 2003, the space shuttle Columbia exploded on reentry, leaving a swath of shattered debris across east Texas. The entire space program was instantly thrown into a disarray from which it has never recovered; the idea of a manned mission to Jupiter suddenly seemed not just preposterous but insane. Along with a bunch of other NASA engineers, Sorensen began, out of necessity, to contemplate his next career move. He had already begun to think of turning away from outer space and delving into the smallest objects in the universe. A supervisor at NASA asked him, “Why don’t you get a graduate degree in nuclear engineering?”
At the time this hardly seemed like a practical suggestion. The nuclear industry had been in the doldrums since the early 1980s, and Sorensen already had one master’s degree. “I remembered graduate school,” he said. “It was painful. I was poor and hungry.” Needless to say, that didn’t stop him.
The nuclear engineering program at the University of Tennessee (UT), which grew out of the lab at nearby Oak Ridge, had not only a storied history but an extensive distance-learning program; Sorensen could stay in Huntsville, keep his job at Marshall (such as it was), and take a class a semester. And the head of the department, Harold L. “Lee” Dodds, had coauthored an important paper on MSRs with Uri Gat and Dick Engel, two of the researchers who worked at Oak Ridge on the MSR experiment under Alvin Weinberg. In the fall of 2003, hardly a propitious time for nuclear power, he started at UT.
Although by that time the so-called nuclear renaissance had begun to gather momentum, nuclear power remained a backwater for promising young scientists and engineers. The near-disaster of Three Mile Island in 1979, and the full-blown disaster at Chernobyl seven years later, which together brought the nuclear power industry to a near standstill in the United States and many European countries, had made nuclear engineering as a profession not only unpromising but also uncool, sinister, and vaguely fascist. Most of the men (they are almost all male) working in the industry in the first decade of the twenty-first century were middle aged and beyond, and few younger engineers were moving up through the ranks to replace them. At one point, around the turn of the century, graduate programs related to nuclear power in the United States, the country that invented nuclear power technology, had fewer than 200 graduate students. Gradually this has changed in the ten years since; nuclear power is now seen as a promising field, in part because lots of people in their sixties and seventies are retiring, and no one in their thirties and forties is available to replace them.
Kirk Sorensen was aware of this gap, but it wasn’t the motivating force behind his career shift. He wanted to change the world, and he’d become convinced that nuclear power—in the form of MSRs, or, more specifically, thorium-based liquid fluoride reactors—was the way to do it. But he quickly ran up against the inherent conservatism of the industry he wanted to transform. Sorensen’s new professors at UT, including Lee Dodds, basically said, “If thorium power was so great, it would’ve been done a long time ago.” It would never happen in their, or Sorensen’s, lifetime.
That exchange well sums up the attitude of what I’ve come to call the nuclearati—the tight fraternity of utility executives, university physicists, nuclear engineers, policy makers, and investors who have, for 30 years, constituted the leadership of the nuclear power industry. In the wake of the Fukushima-Daiichi nuclear accident in Japan, it would be easy to scoff at men like Dodds. These are the same guys, after all, who told us for three decades that nuclear power would be safe and inexpensive. But Dodds is not just the prisoner of his own outworn assumptions; he is representative of a class of men who have spent their careers believing in, and building an industry around, nuclear power. They built the only significant worldwide energy source not based on burning some form of carbon, and they did it in less than a quarter century. It was a remarkable achievement, and it shouldn’t be discounted because the uranium atom has proven less tractable, and the shifting breezes of politics and public perception less predictable than once believed.
Sorensen, at any rate, was once again undeterred. His belief in thorium was undimmed. And as he made his way slowly through the mysteries of nuclear physics and quantum mechanics, he began to think of taking on more of a public advocacy role in the emerging debates about the future of energy.
So he did what any passionate technophile with a cause to promote would have done: he started a blog. Called Energy from Thorium, it debuted on April 22, 2006. The Iraq War was at its bloody peak; the price of oil, which had lingered below $25 a barrel for nearly 25 years, had climbed to almost $60 on its way to nearly $135 in mid-2008. With his poll numbers nosediving, President George W. Bush, a former oilman, had signed an energy-efficiency bill on January 1. Global temperatures were on their way to another of the hottest years on record (according to NASA’s Goddard Institute, nine of the ten hottest years have come since 2000).
Energy from Thorium “is intended to be a location for discussion and education about the value of thorium as a future energy source,” Sorensen wrote in his debut blog post. “Despite the fact that our world is desperately searching for new sources of energy, the value of thorium is not well-understood, even in the ‘nuclear engineering’ community.”
During the next several months, he posted lengthy articles on the history of liquid fluoride reactors and the differences between thermal-spectrum and fast-spectrum reactors (briefly, while the latter operates at high energies, with nothing to moderate, or slow down, emitted neutrons, the former uses a moderator, like water or graphite, to slow down neutrons in order to promote more fission reactions; see chapter 3). He asked, and answered, the question, “How much thorium would it take to power the whole world?” (Answer: about 1,500 metric tons, or something like 2 percent of the annual uranium consumption of the world’s nuclear power industry today.) He also began posting the Oak Ridge MSR documents that had so painstakingly been digitized and burned onto CDs. (When I asked him if that material was in the public domain—and thus not subject to copyright protection—he answered, “I figured they were. Nobody ever said otherwise. I never asked Oak Ridge. I did ask if they wanted a copy of the CDs, but they didn’t even want that.”)
At first writing his blog was like dropping stones into an empty lake. But traffic to the site started climbing steadily, and gradually Sorensen realized that others had experienced the same nuclear epiphany he had. The early proponents of thorium tended to be middle-aged men, mostly with technical backgrounds, many of them lifelong tinkerers and cogitators who shared deep misgivings about the world their grandchildren were going to inherit and a passionate belief that nuclear power, properly developed and safeguarded, could supply the world with the clean, abundant energy it needed. They also had in common a vague disgruntlement: frustrated at the reduced influence of science and engineering in national policy, they suspected that the world undervalued the expertise they’d spent lifetimes accruing. In this, again, they resembled the nuclear establishment. But they were convinced that conventional uranium-based reactors, operated by a hidebound and risk-averse nuclear power industry, were not the answer. Thorium was.
Robert Hargraves had been a math professor at Dartmouth, a consultant for Arthur D. Little for 12 years, and the chief information officer of Boston Scientific, the medical device company. He remembered thorium from his doctoral studies in physics in the 1960s, and when he began to see the element mentioned again in energy discussions, he decided, in retirement, to devote his remaining years (and a chunk of his savings) to it. A frequent commenter on Energy from Thorium and other nuclear blogs, Hargraves taught a class called Rethinking Nuclear Power at Dartmouth’s Institute for Lifelong Education. Joe Bonometti, a West Point grad and a former professor in space systems at the Naval Postgraduate School, worked on the same NASA team researching nuclear-powered spacecraft as Sorensen and Bruce Patton. Like them, he became convinced that thorium in liquid-core reactors represented a fundamental breakthrough that had been too long ignored by the nuclear power industry. Bonometti began leading some of the informal R&D initiatives that arose from the discussion forum attached to Energy from Thorium, aiming to solve some of the outstanding engineering issues surrounding the forgotten technology.
Bonometti’s goal, like that of the nascent thorium community as a whole, was “to ensure that no one in government, or industry, or anywhere else can claim they were blindsided or somehow secretly held in the dark about the technology.”5 They didn’t want to just promote a neglected energy source; they wanted to save the world with liquid fluoride thorium reactors. Technology had gotten us into this mess. The thorium-heads believed that technology could also save us.
John Kutsch ran a design engineering firm in Chicago. A wealthy customer who’d made a fortune in real estate asked him in 2005 to look for investment opportunities around various minerals, including thorium. Kutsch found his way to Energy from Thorium and began communicating with Kirk Sorensen. Like many people new to the thorium discussion, Kutsch was floored to learn that “we have this resource and we’re doing nothing with it,” as he told me in 2009. Kutsch, who bears a certain resemblance to George Costanza from Seinfeld but with more hair, had made an unsuccessful run for Congress a few years earlier. He quickly realized that while Sorensen, Patton, Bonometti, and the rest of the nascent thorium underground had a deep understanding of the technological and scientific issues, they had little capacity or inclination to get things done in the real world.
“The folks at the Energy from Thorium forum are the best there is for technical answers,” Kutsch told me, “but I’m afraid that spending time debating the best way to prevent xenon taint and what to do with transuranics et cetera won’t get anybody any funding, or really anywhere else, any time soon.”
In other words, you can’t cross the ocean by debating the best sailboat designs. You have to build a boat. Determined to do something pragmatic and effective to move the energy industry toward a thorium-based nuclear future, Kutsch set up the Thorium Energy Alliance (TEA), a nonprofit that has organized a series of conferences on thorium power. The TEA managed to catch the attention of the deepest-pocketed player in the new-energy field— Google, which had committed $1 billion to funding renewable, carbon-free energy that is less expensive than coal. In the spring of 2010, I spoke at a conference at Google headquarters in Silicon Valley that was hosted by Dan Reicher, the former assistant secretary of energy who headed up Google’s clean-energy arm. (Reicher has since left Google to direct the Steyer-Taylor Center for Energy Policy and Finance at Stanford.) By early 2011, Kutsch had become one of the most visible activists in the thorium underground, spending much of his time lobbying Congress and raising money—while trying not to neglect his own business.
Then there was Charles Barton Jr. The blog post by Charles Barton on the peak-oil blog The Oil Drum was what first alerted me to the thorium movement, and Barton was the first thorium advocate I spoke to in January 2009. He had inherited his obsession with alternatives to uranium-fueled light-water reactors. His father Charles Barton Sr. was a chemist who’d gone to work at Oak Ridge in 1948, at the dawn of nuclear power, to investigate the chemistry of elements for use in power reactors. Along with many of his colleagues during Alvin Weinberg’s tenure as director, Charles Sr. became swept up in the MSR program—a forerunner of today’s LFTR (explained in more detail in chapter 6)—and wound up becoming the world’s foremost authority on the chemistry of heated liquid salts. Like other Oak Ridge scientists, Charles Sr., who died in January 2009, had spent the twilight of his career watching his work get dismantled and his research discarded. His son, a drug and alcohol counselor, made it his life’s mission to see his father’s work vindicated. Thorium reactors, the younger Barton wrote, will “open up a source of carbon-free energy that can last centuries, even millennia.”
LFTRs, Barton told me, could be built far smaller and less expensively than conventional light-water reactors: “You could build a whole bunch of small reactors, truck them out to sites around the country where you need power plants, dig holes in the ground, put them in, and turn them on.”
TH90 • TH90 • TH90
IT IS, OF COURSE, NOT THAT SIMPLE. I came to realize fairly soon that the tone of the Energy from Thorium forum—geeky, high minded, theoretical, and naive—characterized the thorium movement as a whole. It seemed clear that a small band group of advocates, however committed, had little chance of influencing national energy policy or turning the giant battleship of the nuclear industry.
“The nuclear industry has zero incentive to shift to a new fuel cycle,” Charlie Hess told me. A long-time executive at the architectural engineering firm Burns & Roe, Hess spent 30 years building and operating nuclear plants. Although he is a prototypical member of the nuclearati, he is an advocate of alternative nuclear power, including thorium-based reactors, and a critic of the nuke-power establishment. Fuel costs for uranium reactors are less than half a cent per kilowatt-hour. “They spend more on security guards than they do on fuel,” Hess told me. “Frankly they don’t care.”
That was made clear to me by John Rowe, the CEO of Exelon, the country’s number one producer of nuclear power, when I pulled him aside after a speech at a National Press Club luncheon in Washington, DC. When I asked about the possibility of shifting to thorium as a primary nuclear fuel, he assured me that there “will be alternatives across the entire fuel cycle.” But inexpensive uranium works just fine for Exelon, which has a market capitalization (the total value of its outstanding shares) of $28 billion and made $18.6 billion in revenue in 2010. If it’s not broke, don’t fix it—and nuclear tycoons like John Rowe have convinced themselves that the nuclear power industry is not broken. From the perspective of his office suite, that’s certainly true: Rowe made $10.3 million in 2010, and between 2006 and 2011, his compensation totaled $153.9 million. Uranium reactors have been good to nuclear power executives.
Rowe’s dismissive attitude embodies the obstacles that face the thorium movement, which is composed of outsiders. “Look, the nuclear industry in the U.S. is very conservative,” Ambassador Thomas Graham told me. “I can see interest here in the U.S. gradually developing. But it’s not going to happen here first.” Graham, a long-time diplomat and opponent of nuclear proliferation who served as a President Bill Clinton’s special representative for arms control, now chairs the board of Lightbridge, a company based in McLean, Virginia, that is developing solid fuel thorium rods for conventional reactors. While Graham foresees the use of thorium in the American nuclear power industry at some point, “the initial deployments,” he said, “are going to be abroad.”
Abroad. In the three years I’ve been covering the thorium movement, almost every conversation has at some point included that stipulation. The United States, which dropped the first atomic bomb on Japan at the conclusion of World War II, pioneered nuclear power, built the first commercial power reactors, and invented the liquid-core reactor and first proved that thorium could be used in power-generating reactors, is, barring some unforeseen and unlikely shift in energy policy, almost certainly destined to be a laggard in the worldwide thorium revolution.
France is the world’s largest producer of nuclear power and supplier of uranium for reactors. Eighty percent of its electricity comes from nuclear power, and the energy giant Areva has an active thorium R&D program and is investigating the possibility of building liquid fluoride thorium reactors by 2032. The Laboratoire de Physique Subatomique et de Cosmologie in Grenoble is the only facility in the world that has the resources and backing needed to actually develop a commercial LFTR by 2022.
The Řež nuclear research institute in the Czech Republic is a leader in the development of MSRs and is investigating the possibility of fueling MSRs with thorium, according to the institute’s director.6 Norway, which has an estimated 180,000 tons of thorium reserves, is embarking on an ambitious long-term nuclear power program that includes the construction of thorium-fueled reactors. In Brazil, which has the world’s second-largest thorium reserves and began research into thorium power in the 1960s, R&D efforts have recently begun again to develop thorium-fueled solid fuel reactors. By far the most active thorium power programs, however, are in Asia—particularly in the emerging economic superpowers of India and China.
In February 2011, China officially announced that it will start a program to develop a thorium-fueled molten salt nuclear reactor, taking a crucial step toward replacing coal with nuclear power as a primary energy source. The program was announced at the annual conference in Shanghai of the Chinese Academy of Sciences and is headed by Jiang Mianheng, son of the former Chinese president Jiang Zemin and the holder of a Ph.D. in electrical engineering from Drexel University. The People’s Republic has no intention of falling behind in the race for the next great energy source.
The world’s most ambitious thorium power program, though, is in India, which has the world’s largest thorium reserves. India exploded its first nuclear weapon in 1974 in defiance of the Nuclear Nonproliferation Treaty, and it has always viewed nuclear energy—in both warheads and power reactors—as a key element of national sovereignty. The country has embarked on a three-phase program to build as many as 60 reactors, converting them to run on thorium before 2032.
I will detail the Indian and Chinese programs in chapter 7 and the implications for the United States in the conclusion. Here it is enough to quote the 2011 film The Ides of March, in which the progressive presidential candidate, played by George Clooney, declares, “Either we’re going to lead the world or we’re going to bury our heads in the sand.” The question of thorium is not whether it will become a major source of energy—it will—but when—and where and who will lead the way.