Saturday, October 27, 2012

Latest On Nuclear Fusion

Still Waiting On Nuclear Fusion in Livermore
By Amy Standen from KQED Science by audio report

October 26, 2012 -- The National Ignition Facility in Livermore, California, has been called a modern-day moon-shot, a project of "revolutionary science," and "the mother of all boondoggles."

NIF, as it's known, is a five-billion dollar, taxpayer-funded super laser project whose goal is to create nuclear fusion – a tiny star – inside a laboratory. But so far, that hasn't happened.

The facility, which began operating in 2009 after a decade of construction at a cost of almost $4 billion, points 192 football-field-sized lasers at one tiny capsule the size of a peppercorn and filled with hydrogen.

It creates degrees of heat and pressure never before achieved in a lab.

Standing outside NIF’s target chamber in 2008, about a year before NIF’s dedication, Director Ed Moses called NIF "more far-out, and far cooler than anything in science fiction or fantasy."

A tiny star for a blip in time

"For a brief period of time, not a hundredth or a thousandth, but a billionth of a second," explained Moses, "we will raise the temperature of the target to a hundred million degrees.

"That’s higher temperature and more pressure than exists at the center of our sun. It’s a hundred million times more pressure than you’ll find at the deepest part of the ocean."

Under those conditions, the hydrogen atoms could enter into a state of controlled nuclear fusion. (In nuclear fission, as in nuclear power plants, energy is generated by splitting atoms. Fusion is the opposite: Atoms are smashed together.)

The goal is referred to as "ignition." It would put out more energy than the lasers had put in to it.

If scientists can make ignition happen at NIF, that achievement could, theoretically, be parlayed into a new kind of nuclear power plant. Unlike fission plants, which eat up uranium and generate radioactive waste, these fusion plants would run on water, and create virtually no waste at all.

Waiting to ignite


At NIF's dedication in 2009, George Miller, then-head of the Lawrence Livermore National Laboratory, seemed to believe that ignition was right around the corner.

"I think we will get ignition," Miller told the crowd. "I think we'll get ignition relatively shortly after we turn the facility on."

Since then, the strength and functionality of the lasers have received praise from the physics community.

"The laser has been working phenomenally," said Christopher Deeney, who directs the Division of Defense Science at the National Nuclear Security Administration, which oversees NIF. "It's the most controllable, precise laser the community has ever built."

But ignition – the goal at the center of NIF’s name — hasn’t happened. "We just haven't gotten it to burn yet," explained Moses at a recent interview.

In a July 19, 2012 report, the NNSA concluded that "the probability of igniution before the endf of December is rextremely low."  The report called the functionality of the lasers "outstanding," but blamed NIF’s computer simulations for the failure to ignite.

An NNSA ignition deadline of October 1, 2012, has now come and gone.

Moses bridles at the idea that anyone can put a deadline on this achievement.

"We never guaranteed anything on any particular date," he says. "People have to sort of get used to that.
That’s what great science is."

Nevertheless, by law, on November 30th, Department of Energy Secretary Steven Chu is required to report to Congress on why NIF hasn't met its goal, despite significant cost to taxpayers: about 300 million dollars a year on top of over three billion in construction costs.

For Christopher Paine, a longtime NIF critic with the Natural Resources Defense council, this amounts to an "I told you so" moment.

"This project has gone on a long time," he says, "billions of dollars invested. But to what end?"

What is NIF for?


Paine's criticism of NIF boils down to two objections: the project's expense and what you might call a muddled sense of purpose. What, in other words, is NIF for?

There are three answers to that question, explains a 2009 NIF promotional video.
"NIF will explore controlled nuclear fusion to ensure global security, enable sustainable clean energy, and advance our understanding of the universe."

Let’s break that down.

Reason number one:
Global security. This is the primary intent of NIF, and it has to do with the fact that actual nuclear bomb tests have been banned worldwide.

Because NIF simulates a nuclear reaction in a tiny pellet, you could test the strength of nuclear bombs without having to actually explode them.

Paine believes that’s unnecessary. "We haven’t had NIF for the last 20 years," he says, "and we've been maintaining the stockpile."

NNSA"s Deeney disagrees, calling NIF a "key element in our stockpile stewardship program." He says important experiments can be done at NIF even without ignition.

"We're committed to NIF for the long term," he says.

Reason number two:
Clean, fusion energy. This is a very long-term goal. Even if NIF does achieve ignition, it could take decades to adapt that technology into a working fusion power plant, something that could power a light bulb in your house.

A 100-year solution to a 20-year emergency


Paine says with climate change, we don't have that kind of time.

"Dealing with climate change is a 20-30 year planetary emergency," says Paine. "Fusion energy is irrelevant to that timescale. Humanity needs to change its ways now. It needed to change its ways yesterday. Fusion energy is a 50 to 100-year project with no assurance of success."

But it's the third reason, to "advance our understanding of the universe," that Moses emphasizes these days.

"The Higgs Boson was just discovered at the [Large Hadron Collider] in CERN, at a cost of ten billion dollars," he points out. "Was it late? Was it early? Was it on time?"

The answer, he says: Who cares? Moses calls these types of projects "grand challenge science," and insists they cannot be performed on deadline.

"It’s not grand challenge science if you know the answer before you start," says Moses. "And this is exactly that."

NNSA's Christopher Deeney also declines to predict when NIF will achieve its goal.

"Right now we will not make a prediction of when ignition will happen," he says. "It's still a discovery science project. Right now it's unpredictable."

That's the case NIF's advocates will have to make to Congress at the end of this year. It’s worked so far. After all, NIF has something for both sides of the aisle: Democrats like clean energy, Republicans like weapons security.

But everyone likes a breakthrough, and at NIF, that's still out of reach.

http://science.kqed.org/quest/audio/in-livermore-still-waiting-on-nuclear-fusion/?utm_source=rss&utm_medium=rss&utm_campaign=in-livermore-still-waiting-on-nuclear-fusion

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Comment by the Blog Author
Fusion is a pie-in-the-sky, expensive technical toy that might take decades to become feasible. It eats a lot of government money. But, alone, it has the potential to produce stunningly massive and completely clean energy reliably. Here’s a comment to the article above that was published and is worth reading:

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+1 on money well spent. It'd be cheap at twice the price. Developing fusion energy is the single-most important energy-related, scientific goal at present. Tidal energy, wind, geo-thermal, solar; all of these have potential, but none are as attractive and potentially powerful as fusion. All of them also require huge infrastructure commitments in the forms of complex tidal barriers, vast swathes of land covered with solar/wind generators, or massive mining/drilling projects and exchange plants to pull heat energy (usually in the form of caustic/corrosive gases and liquids) from below the earth's surface. Fusion tech is no small thing; fusion plants would be sizeable and expensive. But they'd be relatively self-contained and generate far more - and cleaner - power per footprint than any of the others. And they can be placed anywhere; no need for sunny climes, geologically active areas, or beautiful coastlines & tidal flats. They can take up the ugliest, most barren real estate on earth, and bring skilled jobs - and resulting wealth - to those areas at the same time.

And that goes for off-world applications as well. If we're ever going to establish mankind permanently on the moon, or Mars, what better way than to do so by powering those outposts with Helium 3, the gold standard of fusionable material that is incredibly rare on Earth, but hugely abundant on the moon?

As with putting a man on the moon, the pursuit of sustainable fusion - literally a quest for fire - should, in the words of JFK, "serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too."

            --Jaq

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