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  • Fusion: The Moving of the Goalposts

    Posted on October 1st, 2013 Helian No comments

    An article about fusion just appeared on the Livescience website promisingly entitled “Fusion Experiments Inch Closer to Break-Even Goal” that is unexceptionable hype except for one little detail; the goalpost for fusion ignition has been moved.  It hasn’t been nudged.  It hasn’t been tweaked.  It has been torn up by the roots, carried down the road a few miles, and planted in an entirely new place that bears no resemblance to the original goal.  The article in question is about fusion experiments at Lawrence Livermore National Laboratory’s (LLNL’s ) National Ignition Facility, usually referred to by its acronym, as the NIF.  The goalpost is that which applies to inertial confinement fusion (ICF), which is the flavor being pursued at LLNL.  The other mainstream approach is magnetic fusion, which will be implemented at the ITER facility currently under construction in France.  Here’s the money quote from the article:

    That got the NIF closer to the “scientific break-even point,” where the amount of energy that comes out of the fusion reaction is equal to that which was put in by the kinetic energy from the implosion. (The energy from the laser isn’t counted in the calculation). Right now, the amount of energy coming out of the NIF setup is about 80 percent of what is put in.

    “NIF is built to ignite a fusion pellet,” said Stewart Prager, director of the Princeton Plasma Physics Laboratory. “They didn’t get it by the time they originally stated, but they are making progress.” The NIF was built in 2008; its original mandate was to achieve ignition — the break-even point — in 2012.

    What’s wrong with this picture?  LLNL explicitly agreed that “ignition” would occur at the point where fusion energy out equals laser energy in.  They did so before a committee of prestigious scientists appointed by the National Academy of Sciences’ National Research Council to review the nation’s ICF program.  It was entirely fitting and proper that they should do so, because that definition puts them on a level playing field with magnetic fusion.  It’s not as if this is a minor point.  After all, the very name of the facility in question is the National Ignition Facility.  Now, suddenly, “ignition” is being redefined as “fusion energy out equals kinetic energy of the implosion put in!”

    Why is this happening?  Because, in spite of recent encouraging progress, the NIF is still a long way from achieving real ignition.  Politicians are griping because the ignition they were promised hasn’t happened, and there have been dark mutterings about defunding the project.  In other words, the NIF’s survival is at stake.  I can see the problem.  What I can’t see is that gross scientific dishonesty is the answer to the problem.  For that strategy to succeed, it is necessary for virtually all the members of Congress to be fools.  Although that is certainly a common assumption, it is not necessarily true.  There are actually a few scientists in Congress, and I doubt that all of them can be hoodwinked into swallowing this latest redefinition of ignition.

    What to do?  Try telling it like it is.  The NIF hasn’t achieved ignition, and maybe it never will.  In spite of that, it remains the finest facility of its kind in the world for accomplishing the mission it was actually funded for; insuring the safety and reliability of our nuclear arsenal.  No facility outside the United States can approach so closely the physical conditions that occur in nuclear explosions.  No other facility is so precise, or has such a fine suite of diagnostics.  The NIF gives us a huge leg up in maintaining our arsenal and avoiding technological surprise as long as nuclear testing is not resumed.  As long as we have such facilities and the rest of the world doesn’t, it would be dumb for us to even think about resuming testing.  It would be throwing away a massive advantage.  Think none of our weaponeers wants to resume testing?  Think again!  The NIF and facilities like it are the best argument against them.  Try pointing that out to Congress.  I suspect it would work better than these ham-handed attempts to move the goalposts.

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