Record laser shot success on the road to fusion energy

Imagine summoning 411 trillion watts of power—1,000 times more than the United States uses in any instant. Q&A with Dr. Ed Moses, Director of National Ignition Facility.

 

Control room staff at the National Ignition Facility monitor the progress of the world’s most energetic laser shot on March 15. From left: Rodrigo Miramontes-Ortiz, Dean LaTray, Scott Phillip Rogers, Dean Steven Felzkowski.
(Damien Jemison/NIF, photo courtesy Lawrence Livermore National Facility)

Imagine summoning 411 trillion watts of power—1,000 times more than the United States uses in any instant—at the flick of a switch, recreating the atom-altering dynamics deep in the core of a star. No, this isn’t a reference to The Avengers movie but an actual scientific experiment meant to give the world a new energy source.

Ed Moses, director of the National Ignition Facility (NIF) in northern California, led the team and established the record-breaking energy output of 1.875 megajoules (MJ) from 192 lasers on Mar. 15, bringing fusion energy, and therefore a clean alternative power source, closer to reality.

For perspective, the record laser shot occurred in 23-billionths of a second. While that does not seem substantial, imagine the power it takes to boil a pot of ice water and then imagine process happening faster than a human could comprehend.

Fusion is regarded as a futuristic and ever-elusive alternative power source. On the blackboard, fusing hydrogen atoms produces enormous amounts of heat which can be captured and developed into an energy source, energy that is safe, cheap, does not burn fossil fuels or consume non-renewable resources.

Unfortunately fusion has had a history of disappointments. Turning the physics of fusion into reality has always been out of reach for engineering technology. The claims of “cold” fusion in the 1990s turned out to be unsubstantiated, leaving scientists and the public justifiably suspicious of “wonder” energy sources coming out of a lab. The giant ITER project in France, which pursues a magnetic fusion technique, has been delayed by huge cost overruns and the ongoing European debt crisis.

However, the NIF has made steady progress towards fusion energy using the world’s most powerful lasers. The record-breaking “shot” was part of ongoing experiments by U.S. government scientists to create fusion by firing the lasers on a tiny pellet of deuterium and tritium fuel. The end result of these experiments is to achieve “ignition” which means inducing more energy out of the process than what was put in.

While ignition may be six months or three years away depending on how future experiments progress, the project has already laid out plans to commercialize the process with the Laser Inertial Fusion Energy (LIFE) project. It has been working with vendors and representatives of the utilities industry in an ambitious quest to begin populating the world with fusion power plants by the 2030s.

I spoke with Moses on the significance of the record-breaking experiment, on what lies ahead for the fusion experiments and the problems of project-managing scientific discoveries.

Canadian Business: You are on the road to achieve ignition with the eventual goal to provide the world with a new source of energy. What was the significance of the 1.8 MJ shot beyond breaking the record?


 

Ed Moses: The goal is not to break records. This is approximately the energy you need (in) the ignition process. So this is what we have been working on getting to for a long time. Believe it or not, these specifications came out of the early-1990s when people truly got comfortable with the idea that 2 MJ is what you need (for ignition). We went off and built the lasers and now we have been operating it and doing experiments and we have confirmed that 2 MJ is just about what you need.

CB: Previous to the building of the NIF, there were doubts that such high-energy could ever be achieved and therefore fears over whether laser fusion would be possible.

EM: At the time of the groundbreaking of NIF (1997), if you looked at what people thought you could do with the laser optics that existed at that time, believe it or not, you needed to make (the optics), around 10 times better. As an engineer you had to make the system one hundred thousand times more resistant to laser damage. And that was a huge risk at the time. During the last 10 years, we have overcome that risk and actually moved the field to a place where we think we can even go higher in energy in years ahead. It’s very exciting. A lot of people said that couldn’t be done.

CB: Part of the laser shot process involves synching the 192 lasers at a target within a capsule and ensuring the target implodes efficiently, without any loss of energy. This symmetry of the implosion was also a big success as well in the Mar. 15 shot. Why was that important?

EM: Just think about the little fuel tank that has the hydrogen in it, that is 2 millimetre across, about the size of a peppercorn. That has to be compressed down to the diameter of your hair and must stay round. And you have to do it in a few billionths of a second. And it’s sort of like if you have a balloon in your hands, if you try and squash it, it won’t stay round, one piece will pop out between your fingers and another piece will move somewhere else. And the whole question is, how do you get that symmetry to happen? So what we did is design a miniature oven that we put the target ball in, we put the lasers into the oven and it gets real hot really uniformly. And that’s how we do to. And you need that symmetry in order to make the target compress—that why you need so many laser beams.

CB: Are there other important milestones ahead?

EM: Yes, there are lots and lots of them. So people have said there were two things that were impossible to do before we started this. One is that we reach 1.8 MJ in energy and we have done that. And the other is to get something called “alpha-burn.” When the process starts happening, you start getting self-heating. You compress the hydrogen and you get conditions when fusion is happening, when tritium and deuterium, special forms of hydrogen, start fusing together making helium, which we have a term for, an alpha-particle. And when that happens the process starts to self-heat.

So alpha-heating is our next big milestone. We’re asking, can you observe the fusion process starting to take off on its own? And that’s really what we’re working on right now.

CB: One of the interesting things about this project is that each laser shot at the target is a progression in a series experiments and tunings that will hopefully lead eventually to a successful ignition shot. It was said that at the beginning of the year there were 100 shots left until the goal is met.

EM: I wouldn’t say it exactly that way. I would say that when we started this process, there were a deliberate number of steps you have to go through in order to make this work. We thought it would take 200 laser shots to targets to make that happen. And we are sort of around 140 right now. What’s interesting about where we are right now is that this is the first time that we’ve gone through all the steps of what we call the tuning campaign, which involved the velocity, the symmetrical shape, the fuel mix and a couple other things and grounded ourselves in the whole process. And so we have, we say, and I can’t guarantee it, another 60 or so shots to finish this process out.

The plan (we had established at the beginning of the project) and where we are now are fairly consistent. On the other hand, I have to say it’s “discovery science” so I can’t guarantee the future but it feels good.

CB: With such a huge endeavor, how do you project-manage basic science discoveries? Would you rather not have set milestones and funding deadlines and such pressures hanging over your head?

EM: Well, I’ve got to tell you it is a stressing environment, not many people are made for it. There are parts of this activity that are clearly manageable as a project. Putting in diagnostics, bringing the laser up to full energy and the like. The National Ignition Facility is a $3.5-billion project. And we won a Project of the Year award for that. So that part of it is good to be project-ized.

Now the basic science part of it, I actually have two points of view. If you don’t handle it in a fairly disciplined manner, I don’t think there’s any chance of being successful. At the same time, it doesn’t really fit into a deterministic project because you’re discovering as you go. So the 140 laser shots we’ve done so far aren’t exactly the 140 shots we’ve planned to do in the beginning. We’ve learned and changed as we go on. But we’re pretty flexible and not dogmatic. I hate the pressure of getting ‘ignition’ on a certain date. It has been overblown by a lot of people. I’ve never thought of it as a date. I’ve thought of it as a process.

CB: At some point does private business begin to participate in the development and funding of the research?

EM: The business world has been in this with us since the beginning. We’ve had 3,000 partners working with us over the past 15 years and that goes from the most high-tech labs and electronics companies to ‘mom and pop’ machine shops. But what’s most interesting now, as we have talked about LIFE, is that major manufacturers in the power industry, architects and engineers who do large scale integration and the like have come to us and are working with us to try and think about how to put this together. I really think energy is a private sector business and they are interested. That’s very encouraging. The other thing is we have a utility advisory board which has many of the major utilities in the United States who are advising us. And actually in Canada, in Alberta, that part of the energy community has shown interest.

CB: This project is progressing in a climate where the U.S.’s and the world’s energy needs and policies are under scrutiny. Last year we had Fukushima, the year before the Gulf Oil spill. Does this unfairly put pressure on your team or does it inspire you?

EM: It inspires me totally. We don’t wish ill on any other form of energy because it serves no purpose. We are in an interesting situation where we have a technology and a need that have coalesced. And they coalesce around fusion. What’s most interesting to me is that it’s age-unlimited. It brings people into the NIF from the most-senior researchers to the youngest brainiacs who want to participate.

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