Playing devil's advocate provides insights into the historical past and up through the contemporary design directions of plasma reactors for electrical power generation. Both the layperson and the fusion expert can gain insight of the last 75 years of fusion reactor design, and why the mysteries of how to control, make stable, select fuel, ash removal, and more, remain mysteries. The attitudes from the initial efforts of scientists to create fusion on Earth, back in the late 1940's, has lasted over 75 years. These attitudes have blinded scientists to alternative approaches. They have not attempted to design for different fuels, designed for less control, or for less stability. One could say fusion device designers are 'locked' into these old fashion attitudes, originating from 1945 onward.
These attitudes are best described by the science writing journalist, Charles Seife. Here is an excerpt from the below book citation.
Sun In A Bottle
The Strange History of Fusion and the Science of Wishful Thinking
By Charles Seife
2008
Excerpt from Page 77
... Years before scientists achieved fusion on Earth, they had realized that the uncontrolled violence of hydrogen bombs was far from an ideal way to harness the sun's power. What physicists really wanted was a fusion reaction they could control. They wanted a reactor that produced energy by fusing hydrogen into helium, and they wanted it to be stable, unlike the dangerous evanescent explosion of a fusion weapon. To create a workable reactor that would tap the unlimited potential of fusion energy, scientists needed to build a sun in a bottle.
In the above excerpt there are notable phrases, listed below, that defy rational, logical, common sense thinking.
- "They could control" - This attitude is still true 70 years later. And no control has been found, yet.
- "it to be stable" - This attitude is still true 70 years later. Struggling to achieve stable fusion remains state of the art ... for decades.
- "fusing hydrogen into helium" - This limit to just 2 Elements is mostly still true. Fortunately, around half the tried fusion reactors in the last decade have non Hydrogen fuel.
- "unlike ... evanescent explosion" - fusion can not use explosions still mostly true. There are a few designs that have accepted they can not achieve self sustained fusion ignition, and now re-ignite fusion many times a second.
- "unlimited potential" - Not true, as when all the fuel is fused ... misleading hype.
- "sun in a bottle" - Where the book got it's title - bottle size keeps growing in trying for stable star like fusion ... since 1960's, some 60 plus years now.
These attitudes lasting 70 years has put blinders on mainstream fusion scientists. Tokamak is not the only fusion solution, as witness by Focused Fusion (LLP) and DARPA-E funding of non Tokamak fusion devices. As well as private funding of over a dozen fusion devices by Bill Gates, Lockheed, and Tri-Alpha, to name a few. The major blinders put on by early fusion scientists that continue today, hampering a truly scientific approach to the creative design process of fusion devices are listed, in order of their impact, from greatest to less.
1) Fusion scientists have looked at hydrogen as the only fuel, and as the most energy release fuel, in the first/only stage of Earth bound fusion devices. Hydrogen is not the most desired fuel, as it releases dangerous neutrons that activate radioactivity in the chamber wall materials, creating nuclear waste, required to be stored for 10,000 years.
An attitude that blinds is hydrogen is the only fuel.
This blind attitude leads to the belief hydrogen is the only efficient fuel. And there are no other fuels which release a larger amount of energy. The belief there are no fuels with greater energy release has no scientific proof, as no one has done a comprehensive study. Why? No one knows all the possible device designs to study.
2) Fusion scientists desire to design a device that can control plasma as hot as the sun. A plasma powerful enough to disintegrate any material it touches, including the chamber wall, blowing out a 20x20x16 cubic foot chunk of a Tokamak. (It happened.)
An attitude that blinds is the desire to control a large quantity of hot plasma.
Engineering economics often have accurate, predictive, mathematical modeling that larger devices are more cost effective than the smaller devices. This viewpoint is honorable when the smaller devices work. Scientific extrapolation into unknown territory with tax payer dollars is rarely done by governments. The state of the art of basic science research, particular in physics, has reach a point where there exists a perception that only large devices will produce new, exciting proof of theory.
"Large is better" is now a constant theme in physics research. It does not have to be. There is still great strides being made with small devices, like laser beam electron accelerators achieving desktop speeds, that even CERN can not reach. By 2015 or so, the desktop fusion device called "Fusor" has 80 individuals stating they fused deuterium. Some as teenagers, in their parent's garage.
3) The desire to go from the unstable thermonuclear bomb explosion, to peace time use of fusion via a slower than explosion, stable, yet massive amount of energy release from the device, results in scaling up the device, based upon predictive math modeling indicating the reduced plasma doughnut curvature can better control the plasma. Stepping into an unknowable extrapolation, where no man has gone before.
An attitude that blinds is the need to have a stable plasma after ignition.
The blinders are coming off where a few reactor designs previous only designed to ignite a fusion reaction just once, and maintain that fusion as a stable fusion for years on end, as the reactor designs have changed, to have multiple ignitions spread over time. From 1,000 ignitions a second, to just a more desirable of 10 or even 1 per second, is dreamed of. Multiple ignitions in Tokamaks are going a few major directions. Methods with many laser beams are instrumental in all of them. One uses the most powerful laser beams ever created. One uses dozens of laser beams. They all aim a small, frozen fuel pellet. One hangs on a cat hair, literally from a cat. One beams into a smaller than a thimble size metal container through special holes and mirrored internal surfaces, to aim the lasers down to a single tiny sphere of frozen fuel atoms. The dream of a 'stable' has escaped some Tokamak designs, in favor of small explosions producing super heated plasma, to replenish for a micro second, the large doughnut shaped plasma where fusion occurs, and heat is drawn off to turn turbines to turn electrical generators for sending to your home.
There are many other small explosion fusion methods, and few are being explored, where funding dollars are scare.
4) Fusion scientists have looked at Helium as the ash product. This ash must be removed from the plasma chamber, otherwise the Helium dilutes the hydrogen plasma fuel, and cools the plasma. Thus, Helium is viewed as undesirable in the fuel.
An attitude that blinds, prevents using Helium as the fuel, or other light Elements, like Carbon, Oxygen, Neon, ..., as the stars do, especially in the late stages of their life time. Stars use additional fusion types other than Hydrogen to Helium, such as fusion Helium in the Triple Alpha process, to make Carbon. And the CNO cycle where Carbon is used to make Nitrogen and Oxygen. Also, the Alpha Process, that is a ladder of Helium fusion with it's own ash product, to make in order, Oxygen, Neon, Magnesium, Silicon, Sulfur, Argon, Calcium, Titanium, Iron and ending at Nickel. These sources of star heat and light are thought to not be possible on the planet Earth. There has been no attempts to disprove this mere "belief." There is no scientific evidence, no published peer reviewed papers definitively proving these other star based fusion types are impossible for mankind.
An attitude that blinds is Helium is an undesireble Ash Product. And is not useful for fusion. While all stars fuse Helium in the two Alpha Processes of Triple Alpha and Alpha Ladder.
SAYINGS
There are many sayings that fit these attitudes.
1) Running before one walks - why not calculate all the possible fuels,
before declaring one fuel as the only fuel, as the best fuel?
2) Grabbing for the Gold Ring, when the bronze ring would work.
The Bronze age lead to the the Iron Age.
3) Put food on the table with bird shot, not a 22. A single bullet can
miss the moving target, while bird shot ensures success.
There are now many fusion reactor designs being funded, 30 balls of bird shot. But might not 300 be better, faster? It is argued the funding level for walking should a similar level as the Tokamak called ITER. The current 500 million dollars spent on new designs might be increased to a matching 100 billion dollars, or at least 10 billion dollars. Why? A bronze ring, an earlier success at fusion power design would be a great boon to mankind.
Get a working fusion reactor by walking, and not attempting to sprint like with ITER whose final design in 2024 is not determined. Yet a giant building is done, surrounded by more giant support buildings. The reactor has many components, giant in size, built and being installed. Yet this sprint's final design is unknown. What other giant components might be necessary, will be necessary to control a stable fusion ring of star fire, at 10 million degrees. If that temperature can be ever stable. Maybe 20 million degrees is necessary with an even harder time of controlling the star hot fusion fuel. To keeping it from bursting loose, and destroying the building and more. The design will be finalized after mathematical modeling is modified in the next 15 years, or more, maybe 30 more years. Testing the ideas in smaller Tokamaks, to a degree is done now. There is no assured ITER success at this time, with 100 billion dollars spent. It's guesswork still. Running before one walks. A new way to do "science" at an industrial level. The benefits to date are great in the areas of new theories of plasma control, new mathematical models based on those theories, and thousands of scientist well versed in sub specialties, but not in breath about general fusion science.
This page summaries many published opinions of great scientists, undisputed by other scientists. It is not bad news, where the messenger must be killed. Instead, this page is a call for walking before running, before sprinting. And a call to continue the sprint attempt. The sprint is producing scientists well versed in very difficult mathematics, and some of these make career changes to fusion projects that are at a walking pace. A good thing, to grow the number of people working on non Tokamak solution directions.