Monday, August 30, 2021

Will Fusion Energy Always Be Forty Years In the Future?


Indulge me in a little stroll down Nerd's Memory Lane.


When I was in high school, I heard about an upcoming talk on nuclear fusion that was going to be part of some publicity event in a new Fort Worth theater.  As my grandmother was the theater director's secretary, that may be how I found out about it.  Anyway, I went.


It was a good crowd, and the guy presenting the talk described what nuclear fusion was in layman's terms, talked about what had been tried so far, and went into considerable detail.  This was probably around 1970, mind you.  Hydrogen bombs (more exactly, thermonuclear weapons) which are still the only way we know how to produce a large amount of energy with fusion, were less than twenty years old.  The speaker may have mentioned tokamaks and plasmas and so on, and while I was listening I thought of a question to ask him at the end.


There were several people lined up before me, and the guy, who looked plenty old enough to me to be an Authority (although he was probably only about 40), patiently answered all the questions people had, even stupid ones.  I was the last person in line.  I asked him if somebody had thought of using feedback control to stabilize plasmas, and he said yes, that was one thing they were considering.  I felt thrilled to have thought of something that would almost certainly become an important source of energy by the time I was his age, or a little older.


Well, fast-forward fifty-one years or so.  No one has yet put a single watt-second of fusion energy into a power grid anywhere.  On the website of the electrical engineering profession's general-interest magazine IEEE Spectrum, there is an interview with a professor of science journalism named Charles Seife who thinks the latest "milestone" announcement by the U. S. National Ignition Facility (NIF) is not so much a milestone as they claim it is.  More like so many minutes on a treadmill, perhaps.


What the NIF announced was that they managed to ignite a lump of fusion fuel to the extent that it made 1.3 megajoules of energy.  Just to put that in perspective, that's about the energy content of a pound (0.45 kg) of gunpowder.  I don't know how many billions of dollars has been spent on the NIF, but if that's all they can do with it so far, it'd be a lot cheaper to wait till New Year's and buy a lot of firecrackers.


Not to be too cynical, Seife admits there is a legitimate reason to keep the NIF running, but he thinks it has little or nothing to do with the practical goal of fusion energy.  The NIF was founded to study nuclear weapons, because the same basic process is used both in thermonuclear weapons and other types of fusion processes.  As long as we in the U. S. wish to remain members of the nuclear-weapon club, we need to keep our thermonuclear powder dry, so to speak, which means maintaining experts that know how to make sure the bombs will go off when we want them to, and not otherwise.  So letting them fool around with stuff like the NIF keeps them occupied and in practice for checking nuclear weapons without actually setting them off above ground, which is forbidden by the Nuclear Test Ban Treaty.  Technically, we can test them underground, but because seismological instruments can tell almost anybody nearly as much about the test as we could find out ourselves, that's not done a whole lot either—the last U. S. underground nuclear test was in 1992. 


However, selling the public on keeping nuclear-weapons scientists in fighting trim is a hard job, while promising them electricity "too cheap to meter"—a famous catch-phrase of early proponents of fusion power—is a lot easier.  The elephant in the fusion lounge is ITER, the International Thermonuclear Experimental Reactor, a multinational collaboration based in France which has been keeping lots of mainly European scientists and engineers busy since 1979, or only a few years after my conversation with the fusion evangelist.  ITER's latest deadline to first make plasma is 2025, although they have had considerable schedule slippage over the years.  And who knows how far it will be between making plasma (which any neon sign does whenever you turn it on) and making money by selling electricity made from fusion energy?


From an ethical point of view, the main issue I see here is how scientists present their work to the public.  Some things are inherently easier to sell in some cultures than others.  For some reason which may have to do with the displacement of faith in God by faith in the Universe or science, U. S. astronomers are able to extract some $30 billion a year from the federal government, roughly speaking (this includes all of NASA's budget and the NSF budget for astronomy-related activities).  In a day when Congress tosses trillions around like popcorn, that doesn't sound like much.  But for an activity which explicitly excludes profit motives—who ever made money off the Andromeda Galaxy?—that's a good chunk of change.  By and large, the public agrees with astronomers that what they do is cool, and pays for it.


Maybe the NIF people need to jazz up the coolness of what they're doing.  I've seen photos of a similar facility, the Z-machine at Sandia Labs, which outdoes anything in Frankenstein's lab for impressiveness.  Of course, just saying you do cool things with sparks or lasers will only take you so far.  But it might be worth a try, rather than setting up goalposts that promise more than they deliver.


Sources:  The interview with Charles Seife is at  The energy comparison with gunpowder is from,48%20J%20of%20explosive%20energy and the date of the last U. S. underground nuclear test is from  A photo of the z-machine in operation is at

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