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| This target chamber is 10 meters in diameter and weighs 287,000 pounds. |
It doesn't look like much from the outside - just a drab, 10-story building on the campus of Lawrence Livermore National Laboratory, about an hour's drive east of San Francisco. But as I'm walking across the parking lot on a sunny day in October I can't help thinking that someday I might be telling my grandchildren about the time I came to this lab and met Edward Moses and saw the technology that was about to change the world.
Maybe this means I'm an optimist. Or even a sucker; a fool. All I know is that when I meet Moses, the 60-year-old scientist who runs this place, and he shows me a tiny pellet, about the size of the multivitamin I take every morning, and swears it will provide an endless supply of safe, clean energy, I want to believe him. It seems so ridiculously simple, so utterly doable. The pellet Moses holds is a model, but the real version will contain a few milligrams of deuterium and tritium, isotopes of hydrogen that can be extracted from water. If you blast the pellet with a powerful laser, you can create a reaction like the one that takes place at the center of the sun. Harness that reaction, and you've created a star on earth, and with the heat from that star you can generate electricity without creating any pollution. Forget about nuke plants, coal, oil, or wind and solar. "This is the real solar power," says Moses.
What Moses is talking about is controlled nuclear fusion - fusing nuclei rather than splitting a nucleus, as happens in ordinary nuclear-fission power plants. In a fission reaction, the nucleus of a uranium atom is split into two smaller atoms, releasing energy in the form of heat. The heat is used to make steam, which drives a turbine and generates electricity. In fusion energy, the second half of this process (heat makes steam makes electricity) remains the same. But instead of splitting the nucleus of an atom, you're trying to force a deuterium nucleus to merge, or fuse, with a tritium nucleus. When that happens, you produce helium and throw off energy.
Scientists have been trying to produce energy with fusion for decades. So far, they keep failing. It's not that fusion itself can't be achieved. Fusion takes place in every hydrogen-bomb explosion. The trick is controlling fusion so that instead of a one-time blast you get a series of tiny, controllable explosions. The joke is that fusion energy is only 40 years away, and will always be only 40 years away.
Moses believes, however, that his lab, which is called the National Ignition Facility, or NIF, has cracked the problem. The big challenge fusion has faced is lack of power. Even the biggest lasers in the world could not generate enough energy to smash nuclei together and make them stick. But the reason the building we're in is so huge - it covers the area of three football fields - is that it contains an enormous laser, or actually a system that combines 192 identical lasers and zaps them into a round chamber, about 30 feet in diameter, where the tiny pellet of fuel awaits the blast. NIF's laser, which took a decade to build and was completed earlier this year, can produce 60 times more energy than any other laser ever built. Right now it's still being tested. But next year Moses and his scientists will fire it up with a full load of deuterium-tritium fuel, and Moses feels confident it will achieve "ignition," meaning a controlled burn in which you get out more energy than you put in. Moses, an award-winning laser scientist with a wry sense of humor, explains the whole thing as he leads me on a tour through the NIF facility. It's a vast, beautiful, awe-inspiring machine, mind-blowing in its complexity, with miles of metal tubes - all part of a system that starts with a tiny pulse of light, channels that light through machines that amplify its intensity and rocket the beam along using specially grown crystals and thousands of lenses and mirrors, and finally focuses these beams down to hit a target that is the size of a peppercorn - all in one millionth of a second.
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| Technicians work inside the target chamber at the Lawerence Livermore National Laboratory. - LLNL gov |
But other scientists warn me that this is all just a high-tech fantasy. They say Moses is full of a certain kind of non-nuclear fuel, and that I should not believe anything he and his colleagues tell me. "They're snake-oil salesmen," says Thomas Cochran, senior scientist with the Natural Resources Defense Council, which has tracked the NIF project from its inception in 1997. Cochran says the NIF laser is still not powerful enough. Even if it were, he says, "these machines are just going to be too big, and too costly, and they'll never be competitive." Other critics, like Stephen Bodner, a Ph.D. physicist who was director of laser-fusion research at the Naval Research Laboratory in Washington, D.C., until his retirement in 1999, say Moses's team has downplayed such technical problems as its inability to focus NIF's laser on a tiny target.
Moses says NIF has already demonstrated the ability to focus onto the target. He's aware of the skepticism but says he's confident that his team, which consists of 500 scientists and engineers, will succeed. His boss, George Miller, the director of Lawrence Livermore, holds a doctorate in physics and is well aware of the difficulties Moses must overcome. "Nothing is a sure game until you've actually done it," he says. But he makes the case for trying. "You have to build NIF to find out whether or not this is going to work."
He's got a point. Big technological breakthroughs require taking big risks. They always seem hopeless and expensive - until they work. Sequencing the human genome seemed impossible until thousands of researchers around the world got it done - in 13 years, with $3 billion in government funding, plus investments by private companies. Like the genome project, fusion energy is something that requires a long-term sustained effort. This isn't like creating the next version of the iPod, or a new application for Facebook. These are scientists operating at the very edge of our knowledge about how to manipulate tiny particles of matter.
If fusion works, it's the ultimate green energy source. But NIF has other goals, one being to help scientists gain greater understanding of the universe itself; for example, they will be able to study conditions that exist inside stars.
Given all that, even if NIF fails - if the whole place turns out to have been a $3.5 billion fiasco - it seems to me that the risk will have been worth taking. The NIF team still will have made lots of smaller breakthroughs in laser design, optics, and materials science. They will have advanced the state of laser science. Then they will go looking for money to build an even bigger laser so they can try again.
And if Moses is right, and NIF succeeds, well, the scientists at NIF will go down in history. That is why labs in Japan, France, the U.K., and China are all pursuing fusion energy too. For his part, Moses really seems not to harbor any doubt. Yes, there are lots of big technical challenges; but one by one, his team is ticking them down, he says. "If someone offered me the job to build a commercial prototype fusion plant and they said, 'You've only got 10 years,' I'd take that job," Moses says. He and a colleague have already branded the product they're building - they call it Laser Inertial Fusion Energy, or LIFE, a name that at least indicates that some scientists also know a bit about marketing. Moses believes that by 2020 utility companies could be building prototype power plants called "LIFE engines." By 2030, he says, real fusion plants could be up and running, and by 2050 they could be common. By 2100, as many as 1,000 fusion reactors could be operating in the United States, if utilities embrace the technology and invest in it.
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| The Lab's Laser Bay 2, commissioned in July, 2007. |
If Moses is right, this may be the biggest technological breakthrough of the century. LIFE would produce energy with no carbon emissions, from a fuel that is cheap and abundant. One comparison fusion proponents like to use is that 10 gallons of water could produce as much energy as a supertanker of oil. We're talking about a solution to global warming, less dependence on foreign oil, and no more need to enrich uranium for nuclear fission - hence no uranium that could be further enriched to make nuclear weapons.
Fusion would be a disruptive technology like the Internet, touching every part of the economy. If the United States can be the first to commercialize fusion, we'll rule the market for green energy and create jobs for half a century as we build and sell power plants to the rest of the world. If someone else gets there first, we'll be buying our power plants from them. Fusion energy represents a potential solution to a looming crisis. The world's population is growing by about 100 million people each year. China and India now use much less energy per capita than we do, but as developing nations industrialize, demand for electricity will skyrocket. Add to that the likelihood that transportation will increasingly be powered by electricity, and we're faced with an insatiable demand. By 2030, global electricity generation will grow nearly 80 percent from 2006 levels, according to the World Resources Institute.
Power companies are already making the pilgrimage to Lawrence Livermore. "Utilities are looking at the future, and they do not have a story for how they're going to make carbon-free energy. Right now, renewables are difficult and expensive," Moses says. The good news is that in March of this year, when Moses and his team fired up the giant laser, they were able to produce more energy than anyone ever had before - just over a megajoule, which, Moses says, "was like breaking the four-minute mile." NIF fires the laser only a few times a day, and scientists are blasting capsules that contain just a tiny bit of deuterium and no tritium. The idea is to test the system and bring it up slowly. Moses says it's like getting behind a Ferrari for the first time; you go easy at first. In a few months NIF will move to a more potent fuel capsule that contains tritium and just a tiny bit of deuterium. By the fall of 2010 the team aims to start blasting capsules that contain the full dose of -deuterium-tritium fuel, and they will crank up the laser power to 1.4 megajoules.
If all goes well, by 2012 NIF will produce what Moses calls "a repeatable, reliable platform." That means it will have worked out a system that utilities could use to start building prototype fusion re-actors. Moses distributes literature with ambitious timelines and even an artist's rendition of a commercial LIFE-engine power plant that looks as if it came from The Jetsons. As for the people who say NIF is a fiasco that will never work no matter how many billions of dollars are spent on it, Moses shrugs and says, "People live in a state of arrested development. They get stuck in one place. They say this can't be done because we couldn't do it in the 1960s. It's like saying we can't have cell phones because we couldn't do cell phones in the 1960s."
Of course, making fusion energy work will be a tad more difficult than making a cell phone. But if Moses and his team succeed, their creation will benefit virtually everyone on the planet. Even if NIF fails, that's a goal worth pursuing.