Forbes on Fusion

Nuclear Fusion Could Be A Silver Bullet — And Just Around The Corner

FEB 12, 2018 @ 08:15 AM Comment by Ken Silverstein, Contributor [“Opinions expressed by Forbes Contributors are their own.”]

This article follows a long tradition of largely-clueless writers repeating long-standing inaccuracies about fusion and possibilities. Let’s see what he does with this (material copied here under fair use for purposes of criticism):

Private investors are now actively trying to commercialize an advanced form of nuclear energy and one that would leave no environmental footprint while also delivering electricity to the world’s expanding population. At issue is nuclear fusion, which has been an elusive concept for six decades but which one firm hopes to makes real by 2025.

Would what he will proceed to describe “leave no environmental footprint”? Compared to what? He will mostly be looking at hot fusion. Nuclear fusion is not an “elusive concept,” it is well-known and understood in one form, and that form has practical applications; for example, “hydrogen bombs” are a practical application, and there are hand-held neutron generators that are another. High-school students have set up fusion reactors in their garages, sometimes using them for the neutron generation, to create isotopes. What is elusive is control of the hot fusion reactions when they are at a scale large enough to make it useful for power generation.

The planned hot fusion reactions will, from copious neutron emission, create radioactive materials in the containment. How serious this is as a problem? Does he even realize that the problem exists?

TAE Technologies, which has backing from a founder of Microsoft Corp. and which uses Google’s algorithms to better mold plasma that is at the core of the fusion technology, says that the concept can be mastered.

Of course, that has been said for 60 years. This is rapidly going downhill. Tae Technologies has, on their web site,

July 27, 2017 TAE Technologies recently announced its ongoing collaboration with Google to apply machine learning to advance plasma research. Together, the team developed the Optometrist Algorithm, which demonstrates that optimal conditions for generating fusion technology are better identified when an element of human choice is added to the experiment.

This is not about “better molding of plasma,” but about what? The “machine learning” here is obviously about the “human element.” This is about information technology, not plasma technology, per se. WTF is the “Optometrist Algorithm??

Neat, published in Nature: Achievement of Sustained Net Plasma Heating in a Fusion Experiment with the Optometrist Algorithm

Really, this is way cool, or hot as the case may be. Optometrists use a device that allows rapid switching of corrective lenses, and narrow on an optimal prescription based on the patient’s assessement of comparative clarity. They do not initially require that the patient prove clarity by reading a Snellen chart or logMAR chart. How does that apply here: Apparently, this is a sorting alogrithm that uses a “subjective” assessment of experimental (input conditions) and results (measurements of plasma temperature or other results).

Machine intelligence might be used to sort through such results and then to suggest development of what Mitchell Swartz calls OOP. Remarkably, that initialism doesn’t seem to be readily found. I had to know what it means to find a reference. Optimal Operating Point, finding which is the goal of much engineering research. There can be more than one, i.e., there can be local minima or maxima, depending on what the goal is.

From the Nature article:

our algorithm asks a human expert to choose between plasma settings based on experimental outcomes. The Optometrist Algorithm attempts to optimise a hidden utility model that the human experts may not be able to express explicitly.

I often talk about this and have written some. Pseudoskeptics in general deprecate what might be called “intuition,” because intuition is not explicitly “rational.” Here, the approach is harnessing “expert intuition,” i.e., presumably informed by experience.

Expert intuition can be wrong, and seriously so, but … it also can be an excellent pointer to further investigation. What can contaminate intuition is attachment, held belief, but where there is no such noise, intuition can be amazingly accurate; human beings are not limited to deductive thinking. Indeed, we evolved, I claim, such that intuition was  primary and deduction was secondary.

Yes, I would expect this to increase efficiency in engineering research.

Application of the Optometrist Algorithm to our plasma fusion problem yielded significant benefits. By deliberately exploring parameter space, we found plasma with better properties, such as stored energy and confinement times. The broader exploration of parameter space also improved the intuition of the human operators. Finally, the most significant outcome was the discovery of an unexpected plasma confinement regime, characterised by a factor of two reduction in the energy loss rate and resultant increase in the plasma temperature.

The one small fly in this ointment: “better” according to whom? “Better” is subjective, unless objectively defined, and looking at a complex situation, that some “properties” were “better” does not guarantee that performance is overall “better.” But, again, the issue is not ontological purity, but, indeed, creating progress, finding “unexpected regimes” and … indeed, improving the intuition of the human operators. I like that they used the word “intuition.” Intuition is silent on mechanism, but we may, if we like, assume that it represents the operation of the massive association engine of the cerebral cortex, most of which occurs outside of conscious process.

This is mostly irrelevant to their actual state of progress, beyond indicating some level of management sophistication. This is the company formerly known as Tri Alpha Energy. 

The section on the target reaction, in that article, addresses the neutron problem.  The reaction is p-B fusion, which is aneutronic, and it only produces hot alpha particles. It may then be possible to harvest the energy more directly. Of hot fusion approaches, this would indeed have the lowest environmental impact.

Basically, the goal is to fuse atoms together, which requires intense heat levels.

That is an assumption of hot fusion approaches. Fusion itself does not necessarily require “intense heat levels,” nor even “high energy.” It can happen at very low temperatures, with a suitable catalyst, the known and clear example being muon-catalyzed fusion. If there is some other form of catalysis, that could be “cold fusion,” which may be mentioned later.

If it could be commercialized, the result would produce 10 million times more power than a conventional power plant — without CO2 emissions and without radioactive materials.

This is very unclear. What does it mean to “produce power”. More electricity? That would be a practical measure. But then, “produce from what”? What is valid here is that p-B fusion, if it can be controlled, has very substantial power production possibilities. Missing is an understanding of the basic concepts, so the text descends into hyperbole — or is it sober? “Conventional power” is based on chemistry, and energy is neither created nor destroyed. “Power” is the rate of conversion of one form of energy to another.

So with conventional power generation, with fossil fuels, energy stored long ago in chemical potential energy is released by oxidation, burning the fuel. That generates hot gases, and eventually that is converted to electricity — unless the application uses heat directly. In nuclear power, the energy is in the form of potential energy stored in nuclei from the beginning of the universe, and when elements are converted, some of this energy is released, leaving the environment actually depleted in that element. This, however, might be considered harmless. We have lots of hydrogen (protons)! Boron is also plentiful. As well, the reaction product, helium, is environmentally harmless. It will escape into space, ultimately.

(The known low energy nuclear reaction, popularly called “cold fusion” converts deuterium into helium.)

“The entire game is to learn how to control the plasma,” Michl Binderbauer, president and chief technology officer for Foothill Ranch, Calif.-based TAE Technologies, in an interview with this writer. “Fusion requires holding this together for long enough at hot enough temperatures. Particles then start to bang at each other. When it is sufficiently hot, the atomic cores collide and fuse together.”

This isn’t wrong, but it’s stated imprecisely. Fusion occurs at any temperature, the issue is rate. So when he says “fusion,” he means “practical fusion.” Particles “bang at each other” — a very fuzzy way of saying that they collide, that imagines intention — and as the collision energies rise, the rate of fusion increases.

“Hot” is a bulk concept. The particles actually don’t “know” how hot the environment is.

 

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