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Calif. Scientists Advance Toward Producing Fusion Energy

March 17, 2009 at 6:40 PM EDT
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Spencer Michels reports on the ongoing efforts of scientists in California, who say they are getting closer to producing fusion energy to help fuel American energy independence.

JIM LEHRER: Next tonight, an update on the long quest for fusion energy. NewsHour correspondent Spencer Michels has our Science Unit report.

SPENCER MICHELS, correspondent: Imagine producing energy the same way the sun does: cheaply, cleanly and infinitely. That’s what scientists like Ed Moses at the Lawrence Livermore National Lab in California say they think they can achieve.

ED MOSES, Lawrence Livermore National Laboratories: Fusion energy is the long-term solution. It is infinite — essentially infinite fuel and it has no carbon waste.

SPENCER MICHELS: Using a newly completed $4 billion laser that has been 10 years in the making, Livermore is getting close to producing controlled fusion and perhaps solving most of the nation’s energy needs.

ED MOSES: This is the largest, highest energy, highest power, most precision flexible laser that’s ever been built and will be that way for many years.

SPENCER MICHELS: Moses, who directs Livermore’s National Ignition Facility, says the laser is finally ready to start experiments that he believes will lead to ignition.

ED MOSES: When we talk about “ignition,” we talk about making a small sun on Earth, getting thermonuclear burn in the laboratory in a controlled manner.

'Sun in a bottle'

SPENCER MICHELS: That burn, or fusion, is what happens in the sun and the stars and in hydrogen bombs. Pieces of mass at the heart of atoms are merged together, fused at very high temperatures, producing enormous amounts of energy, heat, and light.

Fusion is the opposite of fission, which is used in nuclear power reactors. That's where atoms are broken apart. Fusion is also much cleaner.

"Sun in a bottle" is what science writer Charles Seife calls it.

CHARLES SEIFE, New York University: Basically, all life comes eventually from fusion, from the fusion of the sun. And so if we could replicate this on Earth, we've got the clean, elemental power that powers everything on Earth, essentially.

SPENCER MICHELS: For 50 years, scientists have tried without success to create fusion by turning matter into energy. That's what Albert Einstein was theorizing about in "E equals MC-squared," energy equals mass times the speed of light squared.

CHARLES SEIFE: He realized that energy and matter are interconvertible. And what happens is, when you take two very light elements, two light atoms, like hydrogen, and slam them together hard enough, a little mass is converted into energy.

Fusion 'damnably hard'

SPENCER MICHELS: Getting fusion to work in a laboratory is going to be downright tricky. The engineering is unprecedented.

The laser light is fed through a series of tubes, split apart several times, steered through amplifiers that bounce it back and forth, eventually boosting its power by 3 billion, billion times.

Then, the 192 beams are converted into X-rays, before focusing on a tiny ball of hydrogen isotopes inside a cylinder the size of a pill. The X-rays heat the hydrogen atoms to millions of degrees, fusing their nuclei.

The collision that takes place in this intricate sphere, the target chamber, produces energy, as an atomic particle shoots away from the crash site.

ED MOSES: It will make energy, as Einstein told us. The neutron will fly off. And if we collect the energy that's coming out of that, we have fusion energy to use for electricity or a variety of other purposes.

SPENCER MICHELS: The big laser was sold to Congress both as an energy source and as a device that could be used to simulate nuclear explosions, so nuclear weapons could be tested without actually exploding them.

Seven years ago, when we first reported on the Ignition Facility, this project was in jeopardy. It was over-budget and behind schedule, and Congress was considering cutting its funding. But a new management team came on board, and today the controversy has mostly died down.

ED MOSES: We re-baselined, changed the management structure, you know, pretty dramatically, went through a lot of technical reviews, congressional reviews, and the like.

SPENCER MICHELS: Whether the facility will actually produce fusion energy in today's energy-starved world remains a subject of debate.

CHARLES SEIFE: Fusion is damnably hard. I think they've been getting ready to get fusion for 30 years-plus. And I think that they've got a tremendously important machine.

But is this going to actually produce more energy than the laser consumes? Almost certainly not. And in fact, if you press them, they hedge a little bit, "Maybe we'll get ignition; maybe we won't."

Economic, financial issues

SPENCER MICHELS: Ken Fowler, former Livermore scientist and author of "The Fusion Quest," is confident that fusion energy is finally within reach.

KEN FOWLER, professor emeritus, University of California, Berkeley: Oh, I know it will work. The issues are economic and the time that's involved in gathering money to do something this large.

SPENCER MICHELS: There must be scientific issues, as well, that have slowed this thing down.

KEN FOWLER: But the scientific issues are now pretty well understood, and that's why we're doing these big machines now.

SPENCER MICHELS: With such disagreement among experts on fusion's prospects, how are politicians supposed to know what projects to support?

Richard Muller teaches a course at the University of California at Berkeley entitled "Physics for Future Presidents." He says those who control the purse strings for the Ignition Facility must understand the science behind producing energy.

RICHARD MULLER, University of California, Berkeley: These are things the president needs to understand so we can ask the more subtle questions to his science advisers.

Fusion has 'long way to go'

SPENCER MICHELS: Muller says fusion has a long way to go before it can solve energy shortages.

RICHARD MULLER: The lasers are expensive. They can't fire very frequently. Ultimately, what we would want to do is to have lasers fire at a pellet maybe once every second, release this energy every second, and then use that energy to run an electric power plant.

We're not there yet. Right now, we have to find a cheap way to do this, a reliable way. And so far we're just trying to make it work. I think of it as building the first gasoline engine.

SPENCER MICHELS: But Ed Moses is in it for the long haul.

ED MOSES: It is the silver bullet. Of course, there's a lot to do along the way.

SPENCER MICHELS: He estimates that, within a dozen years, pilot fusion power plants that produce more energy than they use will be running. And shortly thereafter, fusion power will be part of our lives.