California's Lawrence Livermore National Laboratory (LLNL) -- located on the grounds of the University of California, Berkley (UC Berkley) -- is the center of a growing controversy regarding a $7B USD laser fusion project, dubbed the "National Ignition Facility" (NIF).
I. LLNL Says Project is Near Fusion, IEEE Editor Says "No Way"
The project -- launched 15 years ago in 1997 -- has yet to achieve "ignition"; the point at which the laser-confined fusion produces more energy than it consumes. And it carries a sticker price of $290M+ USD per year in operating costs.
But those issues didn't stop LLNL from releasing a cheerful press release, proclaiming:
Fifteen years of work by the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) team paid off on July 5 with a historic record-breaking laser shot. The NIF laser system of 192 beams delivered more than 500 trillion watts (terawatts or TW) of peak power and 1.85 megajoules (MJ) of ultraviolet laser light to its target. Five hundred terawatts is 1,000 times more power than the United States uses at any instant in time, and 1.85 megajoules of energy is about 100 times what any other laser regularly produces today.
The release was hardly coincidental. It came just months ago, in hopes of swaying Congress, which is presently deciding whether to sustain funding for the troubled project.
But according to IEEE Spectrum editor Bill Sweet, a veteran of India's nuclear power development project, most physicists view laser-contained (aka. "inertial confinement") fusion ignition as a pipe dream. He argues that most agree that magnetic confinement fusion is far more likely to be realized, though still a difficult problem.
William Broad, chief nuclear issues reporter for The New York Times, agrees. He writes that the National Nuclear Security Administration's project overseer, Donald L. Cook, has serious concerns. He quotes Mr. Cook as saying, that even with the latest power milestone considered, the project simply "has not worked", and that the NNSA is "going to settle into a serious investigation" of the NIF's sliding ignition deadline.
II. Protecting the Nuclear Stockpile? Maybe Not...
Mr. Sweet also takes issue with LLNL's other justification for the project -- that it provides a test-bed to simulate nuclear weapons performance, a key national security goal.
LLNL comments, "[The NIF] is the only facility with the potential to duplicate the actual phenomena that occur in the heart of a modern nuclear device -- a goal that is critical to sustaining confidence that a return to underground nuclear testing remains unnecessary."
But Mr. Sweet counters, "Richard Garwin, for decades the most highly regarded independent specialist on nuclear weaponry in the United States, told IEEE Spectrum six years ago that it would be 'a mistake to assume that NIF experiments are going to be directly relevant to weapons testing. The temperatures in the NIF chamber are much lower than they are in actual nuclear weapons, and the amounts of material being tested are much smaller.'"
He adds, "For decades the joke about magnetic confinement fusion--much the more plausible approach to harnessing the energy of the sun--is that the technology is always 20 years away. So when will inertial confinement fusion be delivering commercial electricity? That one is easy. Never."
It sounds like there's some serious credibility question regarding the project's security and energy claims. That said, there might be some merit to the project, even if Mr. Sweet is at least partially right.
UC Berkley astronomy Professor Dr. Raymond Jeanloz, comments, "Already the most incredibly tightly controlled and most energetic laser in the world, it is remarkable that NIF has achieved the 500 TW milestone - quite a significant achievement. This breakthrough will give us incredible new opportunities in studying materials at extreme conditions."
Indeed, from a pure science perspective, the device is a pretty impressive accomplishment, even if it turns out its fusion goals are indeed pipe dreams. It could indeed yield some novel materials research, if it escapes this round of funding reviews. Ultimately the issue appears not so much that the super-laser lacks novelty, but rather that its critics argue that it is being misrepresented. For that reason, Mr. Sweet infers, the NIF is the "mother of all boondoggles".
Sources: IEEE Spectrum, LLNL, The New York Times
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