Sunday, January 10, 2016

An Open Letter to Congressman Alan Grayson On Fusion

Introduction:

       Fusion has the power to change the course of human history.  It could curb climate change - a clear threat to human civilization.  Fusion research is littered with great ideas that we have never tried.  We have failed to support so many great ideas.  This must change.  We cannot wait.  Our leaders must hear this call to action. 


      In August of 2015, Congressman Alan Grayson introduced HR.3440: The Fusion Innovation Act Of 2015.  This bill calls for changes to federal US fusion funding.  I decided to write his staff an open letter covering what changes we think are needed.  Enjoy.






Executive Summary:

     This letter calls for an overhaul of US federal support for nuclear fusion.  It is addressed to Representative Alan Grayson, who introduced "The Fusion Innovation Act Of 2015” into the 114th Congress.  Presently, federal funding is narrowly focused on laser fusion or tokamaks, neither of which will be commercially viable.  This narrowing has happened because fusion shifted from practical to esoteric research, poorly communicated its’ advancements, lost funding for a diversity of ideas and did not compare all of its' approaches objectively.  ITERs’ high cost (~16 to 50 billion USD), size (~23,000 tons of steel), delays (over 7 years presently) and hazards make it unlikely to lead to commercial fusion.  NIFs’ failure to get ignition led Livermore to cancel the Laser Inertial Fusion Energy (LIFE) program in 2014.  Meanwhile, fusion can be done cheaply by non-specialists, using common tools.  Moreover, several outside groups have made progress in spite of a lack of government support, including: Tri Alpha Energy, Energy Matter Conversion Company, General Fusion, the Northwest Nuclear Consortium, Hyper V, Lockheed Martin and Helion.  U.S. federal support for fusion must change; changes should start with rating machines using John Lawsons’ original energy balance, not derived metrics like the triple product.  Next, the mission of the Fusion Energy Sciences Office, should be both expanded and modified.  Congress should refrain from calling for yet another review panel which will wastes time.  Funding should be increased for shovel-ready projects such as EMC2s’ polywell (30 million over 3 years) MITs’ LDX (2 million per year) LANLs’ PLX (tens of millions) the dynomak (35 million over 3 years).  Additionally, an expanded SBIR program should be created that focuses on fusion startups. Government funding should be closer to venture capital; with a real possibility of losing funding.  Finally, the Northwest Nuclear Consortium should be examined as a model for high school fusion education. For example, grants could be made available for high schools to build small fusors.  The letter closes with a comparison between flight and fusion.  

Opening:

      I am writing in support of H.R.3440.  Your proposed bill, “The Fusion Innovation Act Of 2015” is the first fusion legislation we have seen in a long time.  We need Congress to pass some kind of fusion research reform.  For almost 10 years I have been working in fusion, either as a researcher or as a promoter.  I cannot express to you strongly enough how lopsided the U.S. Government-funded fusion research is right now.  Presently, a handful of concepts get all the talent, funding and resources.  Ironically, these are arguably the furthest away from commercial viability.  Meanwhile, many other approaches have been left out in the cold, with nearly no government support. We have been stuck in this rut for many decades.  But today, despite inaction at the federal level, fusion research is advancing.  This will likely continue with or without U. S. government support.  Reform is needed so that the United States can stay on top of the newest technologies, concepts and developments.  Fusion power would have serious implications for the economic, environmental, defense and moral might of the United States.  This is not something we should let slip by.  We need to lead on this issue, and we are not leading.  

What got us are here:

     Several overlapping trends have led to our current situation.  Currently, the U.S. fusion world consists of a spectrum of universities, laboratories and companies.  Most of these groups are focused on one of two concepts: ICF or Tokamaks.  This makes for a very narrow environment.  There have been supporters and critics of this narrowing approach over the past 20 years.  Supporters argue that ICF and Tokamaks approaches are the most promising scientifically.  Critics argue that this narrowing has devastated fusion research.  There are several reasons why the critics have a stronger case.  First, what is interesting scientifically may not be useful commercially.  NIF and ITER are both interesting scientific machines but they will likely never lead to commercial viability (I show this below).  Next, have these machines shown strong results because of their merits or because they have received hundreds of millions of dollars in funding? 

      This is tough to answer, because there is little data comparing all fusion concepts.  There is no textbook that compares all of the approaches to fusion by net power, efficiency, beta, size, power balance or cost.  Worse, there is no funding to pay someone to write such a book, nor is anyone trying to write it.  This lack of feedback is another negative effect of the narrowing.  When researchers are not threatened by other approaches they see no need to compare their work.   This narrowing has also killed innovation.  Today, most fusion innovations are merely plays off the existing ICF or Tokamak devices.  For example, the ICF approach has direct drive, indirect drive, fast ignition and heavy ion beam fusion.  Unfortunately, all of these concepts are based on the same platform, which means they all suffer from similar commercial and physical limitations.  The narrowing approach also kills innovation by forcing all other programs to “show relevancy to ITER or NIF”.  Projects must be tied to the flagship machines or their funding is cut.  Researchers have also shifted away from focusing on practical, commercial concepts to esoteric publications and maintaining funding.  People have put more of an emphasis on upholding their careers rather than finding commercially viable fusion. 

      Finally, the scientific community has done a poor job communicating developments in fusion, both internally and externally.  They may communicate with technocrats in Washington, but do not explain themselves to the general public.  This has gradually led to a lack of public awareness.  Naturally, this has led to a lack of political leadership.  Taken together, these effects have killed a diversity of approaches, driven researchers away and left the United States in a bad place.  We are stuck with NIF and ITER – and neither is very promising.

Problems with ITER and NIF:

                ITER is an interesting project, but it will never lead to a Tokamak-based power plant.  The projected cost is anywhere from 16 to 50 billion dollars [1-4].  That amount is far too high for commercial uses.  It is estimated that that the core will be 60 times more massive than a fission core - roughly 23,000 tons of steel [5].  That is too big to be commercially viable.  Originally, the machine was supposed to open in 2016 [6].  It is presently over seven years delayed [7].  The machine can accidentally quench, creating sudden fires which release radioactive waste [5].  This warrants an expensive safety system.  Realize that any commercial plant based on the Tokamak concept will likely be more complicated, costly, time consuming and hazardous than the ITER prototype.  So any commercial device would indeed be monstrous.  This machine would then need to be regulated by the NRC [5]. And finally, it would need to turn a profit.  It is a fantasy to think that such a project will lead to a commercially viable reactor.  It is too extreme for private industry to take on.  Supporters will argue that even if it fails, ITER will lead to a raft of spin-off technologies.  In fact, the spin-off technologies (materials, magnets, diagnostics and plasma heating) could be developed separately, decoupled from the ITER project.  Moreover, ITER’s existence spreads the false perception that fusion is big, expensive and ivory tower, when in fact, nuclear fusion can be done by teenagers in their basements using cheap fusors [8].  Bottom line: we do not need to wait seven years to find out that ITER will never lead to commercial power - and then back out.  We know this right now.

     The course taken by ITER bears a striking resemblance to the smaller National Ignition Facility (NIF) at Lawrence Livermore National Laboratory.  The facility failed to get ignition after $3.5 billion was spent on it [9].  When it was turned on, NIF was so complex that researchers could not connect parameters to different results – a basic requirement for valid scientific experiments.  A NIF implosion takes about 20 nanoseconds and occurs in a space of ~1E-7 cubic meters [10, 11].   Building the sixty tools to measure the implosion is a feat of science, but a NIF based system will never be commercially viable with such ridiculous constraints [10, 11].  It speaks volumes that Livermore quietly killed the Laser Inertial Fusion Energy (LIFE) program last year [12].  It was a quiet admission of a colossal misstep.  A similar failure at ITER will be far worse because it will be more costly and more time consuming than NIF.

Lawson Criteria:

                Both flagship ICF and Tokamak machines are failing to lead to commercial viability.  But this is certainly not what you hear from ICF or Tokamak researchers.  One figure of merit they use to prove that these approaches will work is the Lawson criteria.  This is so widely used in the fusion that it is worth clarifying.  In the 1950s John Lawson wrote a landmark paper about what it would take to get fusion power.  Lawson applied the following energy balance across a plasma-base fusion machine [13].

Net Power = Efficiency*(Fusion – Conduction – Radiation)

To get net power, we need to beat this equation.  This should be a major focus inside the fusion community.  At present, it is not.  Most fusion researchers have taken this energy balance and adapted it to support their research.  This has led to a focus on minimum triple products, experimentally achieved ignition thresholds and a multitude of abstract figures of merit [14].  Fusion power will likely come from people who ignore all those derived metrics and just beat the energy balance directly.  There are likely unexplored avenues to do so.    

Change starts at the FES:

      These problems must be hard to see from inside the beltway.  For example, the Office of Fusion Energy Sciences can tout its many real successes.  I do not want to detract from their efforts.  They do get many things right.  The office does a good job of fulfilling mandates from Congress.  It also does a good job of maintaining the existing fusion facilities, staffers and concepts.  But, it has become clear that this status quo will not lead to commercial viability.  Tokamaks and ICF are not on a path commercial viability.  This has not changed the behavior of the Office of Fusion Energy Sciences.  If anything, it has made them far more dogmatic.  One staffer explained to me that, “the alternatives will fade away and all that’s left will be ITER and NIF”.   That would be disastrous.  It would waste precious time and money, eliminate diversity and leave us with two options, neither of which are commercially viable – at a time when the human race needs zero carbon energy sources.

Fusion Tribalism:

     Fusion looks very different from outside the NIF and ITER communities.  One person described this world as “fusion tribalism”.  It consists of a multitude of disconnected ragtag groups supporting specific concepts.  They are convinced that the world needs fusion power and that their approach will make it a reality.  They work, in spite of government support, not because of it.  Many feel that the DOE should expand its support to encompass these groups, or at the very least find ways to encourage their growth.  One good suggestion would be an expanded SBIR program focused specifically on experimental fusion concepts.  The reasoning for this is that commercial fusion power is more likely to come from one of these outside groups rather than the flagship machines.  This is a high-risk investment and many of these teams and concepts will fail.  However, one success would reap great rewards for the United States.  Moreover, if fusion power was developed by a competing nation or group, it could be disastrous.  Below is a list of some of the groups for your staff to review – it is by no means exhaustive.    


1. Tri Alpha Energy. This company is a poster-child for the problems created by a limited DOE vision.  The company recently demonstrated the longest stable field reverse configuration (FRC) ever.  They pulled this off with roughly the same concept they had when founding the company in 1998 [15].  This concept involves using particle beams to stabilize a field reversed configuration.  Had the U.S. Government helped the company years ago, we would have likely gotten to these results much sooner.  Tri Alpha is now gearing up for a much longer test. 


2. General Fusion. This company was founded in 2002 by Dr. Michel Laberge in Canada [16].  The technology involves the compression of a Spheromak (presently), or a Field Reversed Configuration [17].  The concept was partially developed at Los Alamos National Laboratories in the seventies [18].  It was not pursued because the plasma compression could not be coordinated.  Today this is possible.  General Fusion has a staff of ~50 and they have raised over $55 million in investment [19]. They have put out dozens of presentations and about 10 papers.  The strength of their technology is that the surrounding lead-lithium is well suited to deal with the fusion by-products.


3. Energy Matter Conversion. This team just published a major paper in Physical Reviews X.  The paper provides data showing that they made a cusp-confined plasma inside a magnetic device [20].  This is a theoretical condition where the plasma’s own internal magnetic field rejects the outside magnetic field, leading to a powerful (beta = one) plasma trap [21].  If this research bears out, it would distinguish cusp confinement as radical alternative to trapping a magnetized plasma, which will have significant implications for fusion research. The group is now attempting to raise 30 million dollars over the next three years to develop this concept [22].


 4. Convergent Scientific Inc. This a very small team working in Washington state.  The company is developing a modified version of the Polywell.  Raising and spending less than $150K, they were able to concentrate a plasma for 20 seconds inside a prototype device [23].  The group has also developed an innovative plasma simulation software.  They are continuing to raise money and are gearing up for further containment experiments.  


5. Lockheed Martin. Lockheed has been rightly criticized for not publishing their work in a peer-reviewed journal. What we know about their approach comes from three patents, several media stories and talks [24].  Their concept uses cusp confinement to trap plasma while heating it with neutral beam injection [24].  A good estimate is that Lockheed has $5 to 10 million invested in the project and a staff of 6 to 8 people.


6. Helion.  Helion was spun-off from Mathematical Sciences of the Northwest (MSNW) in 2010 [25].  Both companies were founded by Dr. John Slough, both are working on fusion and both have received government funding.  This funding totals less than $25 million in almost as many years [19].  The company has heated plasma to a temperature of five thousand electron-volts, roughly a fourth of the goal set by the National Ignition Facility [25, 26].  They have also demonstrated a containment field of over one hundred Teslas in strength [25]. 




7. Levitating Dipole Experiment. This is an innovative machine that was pursued jointly by Jay Kesner at MIT and Michael Manual at Columbia.  The dipole is a levitating magnetic donut, which is free floating inside a high-pressure plasma. Fuel (deuterium) is introduced at the plasma edge and is driven inwards by the so-called “turbulent pinch”. Fusion would occur in the high density inner region.  The team was planning ion heating experiments which could lead to ignition experiments, but in 2010 the fusion funding for the LDX was cut [27, 28]. Today the principals are searching for funds to restart research.


8.  HyperV and PLX. The Plasma Liner Experiment at Los Alamos has been sold as a middle ground between ICF and Tokamaks.  First proposed in the late nineties, the idea is to inject a plasma structure (like a field reversed configuration) into a chamber and compress it with plasma cannons [29].  The idea builds on, but is arguably better than, ICF and Tokamaks.  It is smaller, cheaper and is physically less constrained.  Surprisingly, even such a mainstream concept still took over 10 years to get the funding for a full test [29, 30].  We should have accelerated its development.   


9.  Northwest Nuclear Consortium. This is not a company - but a group your staff should be aware of nonetheless.  The NWNC is the only high school club in America with their own nuclear fusion device.  The group was founded in 2010 by Carl Geinger [31].  Incredibly, these teens do fusion using a fusor every weekend in a home outside Seattle.  They have won over $600K in college scholarships and came in 2nd place in 2013 at the Intel International Science and Engineering Fair [31].  Supporters want to duplicate this high school fusion program at other high schools around the country. 

      There are other companies that could be added here.  They include small groups of people with very good ideas.  This cluster of companies represents a fundamental shift inside the fusion research world.  They are quite different from the firms which have come before because they exist in a hotter, more connected and technically advanced world.  Collectively, they are still small.  In 2014, I tabulated that among the dozen or so companies, there were 330 people working with $450 million invested [19].  Despite being small, they are innovative and very nimble.  The government has not devoted the resources to staying on top of their technology.  Moreover, far from going away, new firms are popping up every year - lured by the prospect for clean, cheap energy.

Changes Needed:

                 In a perfect world, the federal government should both increase and modify its support for fusion research.  The government should avoid its habit of calling for yet another review panel, assessment or study.  There have been many panels over the years.  They waste time and tax dollars and they tend to come to the same conclusions. They typically call for increased funding, which is typically ignored.  This delays research until a new administration calls for a new panel whose recommendations are also ignored.  This cycle of inaction is very familiar to fusion researchers.  Buck this trend.  Take action right now.  Funding should be increased immediately for several shovel-ready fusion projects: the EMC2 Polywell project ($30 million over 3 years) the Dynomak at the University of Washington ($35 million), the LDX at MIT (2 million per year), the PLX machine at Los Alamos and Wisconsin’s IEC research center.  Wisconsin alone may not even be enough to deal with developments in fusors – a growing community amateurs are claiming higher neutron rates as of late and Australian researcher have started developing magnetically insulated fusors [32, 33].  There also needs to be an increase in the SBIR program for small fusion companies.  In addition, the Northwest Nuclear Consortium should be examined as a model for high school fusion programs across the country.  This would fit nicely into the broader push for STEM education.  One suggestion is a grant program that enables schools to build their own fusion devices on campus.  On top of this, the government needs to change the nature of its' funding.  The U.S. government should fund fusion on a much more competitive basis – more like a venture capital firm rather than a blank check.  This means including the real possibility of cutting funds for boondoggles and bad concepts.

In Closing: A Story

                In 1903, powered flight was invented by two nobodies without a college education, federal funds or any university support.  It was done at a time when powered flight was widely considered impossible, by both the general public and esteemed experts.  Just nine days earlier, the highly visible federally funded program had been abandoned.  Powered flight happened because there was a great need and a determined community willing to try.  It was not just an innovation, it was an invention beyond our collective imaginations.  Its creation came from a direction that no one would have predicted.  Its impact was radical, unexpected and far reaching.  History tells us that it is hard to pre-plan for these radical innovations.  It is hard to know the shape of technologies before they exist.  For fusion, this means never being 100% sure we know what fusion power looks like until it is real.  Today, we must recognize that a similar community with similar motivations is budding around fusion.  Today, there is a staggering need for this energy source and many more people eyeing this prize. And today, the technological barriers are coming down much faster than most people realize.  The U.S. Government needs to be on top of all these developments.  Make no mistake: we are not leading.  We must change.

Citations:

1. "ITER - the Way to New Energy." ITER Project Milestones. ITER, 2013. Web. 06 Oct. 2015.
2. Cho, Adrian. "Cost Skyrockets for United States' Share of ITER Fusion Project." Science Insider. Science/AAAS, 10 Apr. 2014. Web. 27 Oct. 2014.
3. "Currency Calculator Converter Euro to US Dollar." Currency Calculator (Euro, US Dollar). X-Rates, 27 Oct. 2014. Web. 27 Oct. 2014.http://www.x-rates.com/calculator/
4. "Fusion Furor." Nature.com. Nature Publishing Group, 23 July 2014. Web. 27 Oct. 2014. http://www.nature.com/news/fusion-furore-1.15596
5. Hirsch, Robert L. "Fusion Research: Time to Set a New Path." Issues in Science and Technology 31, no. 4 (Summer 2015).
6. Portone, Alfredo, D. J. Campbell and A. Loarte. "The ITER Plasma Control Challenge." European Fusion Development Agreement. San Diego. 11 May 2006. Lecture.
7. Gibne, Elizabeth. "Five-year Delay Would Spell End of ITER." Nature.com. Nature Publishing Group, 31 July 2014. Web. 06 Oct. 2015.
8. Clynes, Tom. The Boy Who Played with Fusion: Extreme Science, Extreme Parenting, and How to Make a Star. N.p.: n.p., n.d. Print.
8. "NIF FAQ - How Much Did NIF Cost?" Frequently Asked Questions. LLNL, The National Ignition Facility, n.d. Web. 1 Apr. 2013.
9. "Wired Science: The World's Most Powerful Lasers." Wired Science. YouTube, 12 Oct. 2008. Web. 01 Apr. 2013.
10. Haan, Steven. "NIF Targets: Baseline Design." NIF Targets. Lawrence Livermore National Laboratory, 1999. Web. 01 Apr. 2013.
11. Kramer, David. "Livermore Ends LIFE." Livermore Ends LIFE. Physics Today, Apr. 2014. Web. 17 May 2014.
12. J D Lawson. Some criteria for a power producing thermonuclear reactor. Proceedings of the Physical Society. Section B, 70(1):6, 1957.
13. “Special Topic: Plans for the National Ignition Campaign (NIC) on the National Ignition Facility (NIF): On the threshold of initiating ignition experiments “ JD Lindl and E Moses, Physics of Plasmas 18, 050901 (2011).
14. “Form D - Notice of Sale of Tri Alpha Securities” August 8th 2003, George P Sealy, Vulcan Ventures, James Valentine, Allen Puckett, Prouty Family Trust, Dale Prouty, Porridge LLC, Harry Hamlin, Andrew Conrad, Michael Buchanan, James Boyden, Michl Binderbauer.
15. "Rethink Fusion." http://www.generalfusion.com/. General Fusion Web. 22 Dec. 2015.
16. Michael Delage. Private Conversation, Monday November 23rd, 2015.
17. "Michel Laberge: How Synchronized Hammer Strikes Could Generate Nuclear Fusion". Perf. Michel Laberge. TED 2014, Vancouver Canada, March 2014.
18. "The Polywell Blog." An Industry Emerges. The Polywell Blog, 18 Jan. 2015. Web. 22 Dec. 2015.
19. Park, J. "High-Energy Electron Confinement in a Magnetic Cusp Configuration." Physical Review X. N.p., 11 June 2015. Web. 06 Nov. 2015.
20. J. L. Tuck, A new plasma confinement geometry, Nature (London) 187, 863 (1960).
21. Park, Jaeyoung. "Polywell Fusion: Electrostatic Fusion in a Magnetic Cusp." Microsoft Research. Microsoft Inc, 22 Jan. 2015. Web. 20 July 2015.
22. "Some Questions about Your Work." Interview by Devlin Baker. Email 16 Jan. 2014: n. pag. Web. 17 Jan. 2014.
23. McGuire, Thomas. "The Lockheed Martin Compact Fusion Reactor." Thursday Colloquium. Princeton University, Princeton. 6 Aug. 2015. Lecture.
24. Slough, John. "About us" Helion Energy. http://www.helionenergy.com/ N.p., 2015. Web. 22 Dec. 2015.
25. "Development of the Indirect‐drive Approach to Inertial Confinement Fusion and the Target Physics Basis for Ignition and Gain." John Lindl. Page: 3937.  AIP Physics of Plasma. American Institute of Physics, 14 June 1995.
26. "MIT, Columbia Engineering in New Joint Project to Explore Space Weather." MIT News. N.p., 26 July 2012. Web. 22 Dec. 2015.
27. Private communication with Jay Kesner. "Questions on the LDX" December 11, 2015.
28. Thio, Y.c.f., R.c. Kirkpatrick, C. Knapp, E. Panarella, F.j. Wysocki, and P. Parks. "An Embodiment of the Magnetized Target Fusion Concept in a Spherical Geometry with Stand-off Drivers." 25th Anniversary, IEEE Conference Record - Abstracts. 1998 IEEE International Conference on Plasma Science (Cat. No.98CH36221) (1998): n. pag. Web.
29. McGrath, Patrick. "Plasma Liners For Fusion." ARPA-E Press Release, 14 May 2015. Web. 22 Dec. 2015. http://arpa-e.energy.gov/?q=slick-sheet-project/plasma-liners-fusion.
30. Geinger, Carl. The Northwest Nuclear Consortium. Northwest Nuclear Consortium, 2015. Web. 22 Dec. 2015. .
31. Hedditch, John. "ArXiv.org Physics ArXiv:1510.01788." Fusion in a Magnetically-shielded-grid Inertial Electrostatic Confinement Device. ArXiv, 7 Oct. 2015. Web. 22 Dec. 2015. .
32. Schatzkin, Paul. "Doug Coulter’s Solar Powered Star In A Jar." Fusornet. N.p., 29 Oct. 2015. Web. 22 Dec. 2015. .

Saturday, November 7, 2015

The Worlds Best Plasma Trap


The Worlds’ Best Plasma Trap


Introduction:


      There is an exciting idea on the edge of fusion research.  The idea is to use a plasmas’ magnetic properties to hold it in.  This is not new; but it is getting renewed interest.  In these plasmas, the soup of ions and electrons make their own fields - which are used to hold them in [40].  There are three recent examples of this:


1. Lockheed Martin.  Lockheed is trying to make a machine where the plasma rejects the outside field [41].  The plasma goes diamagnetic.  It pushes out the field, creating a region with no magnetic field; a region with high pressure plasma.  This is known as cusp confinement [10, 14, 15].


2. Field Reverse Configuration.  These devices create a spinning soup of ions and electrons.  The moving charge makes its own magnetic fields – which self contains the plasma [42].  


3. EMC2 Cusp Confinement Work.  In a paper published over the summer, EMC2 gave data of a cusp confined plasma [43].  The company saw two zones inside the machine.  In the center, there were high energy ions and electrons ricocheting around, with nearly no field.  Surrounding this, were magnetic fields, with nearly no plasma. 


I cannot understand why we are not seeing this topic addressed in the journals.  One reason is that the data is new that folks are still skeptical.  Another is that most physicists work with plasmas which mingle with the fields; like tokamaks and stellarators.  It is not the convention.  Critics will argue that these concepts have not reached high enough temperatures to be taken seriously. I argue that temperature, density and time are not as important metrics as fusion, conduction and radiation rates. They are not as important as cost, size and efficiency.  Moreover, if cusp confinement works is should lower the overall required volume and plasma needed - lowering mass loss and trapping higher pressure plasma in a smaller space.  This should be a reason to re-evaluate what we think we know about fusion machines. 



Executive Summary:


      This post lays out the history of cusp confinement and walks through EMC2 experiment.  A set of approaches - field reverse configurations, polywells and the compact fusion reactor - attempt to use the plasmas magnetic properties to self-contain it.  Cusp confinement is one such method which reduces plasma losses to the axes and edges of cusp.  Ideally, it leads to a free-boundary plasma by plugging the cusps with a high pressure plasma, forming a field-free region.  EMC2 recently provided data of such an effect.  Their new polywell is safer, more efficient and reaches a magnetic density 1.5 times higher than WB6.  High pressure carbon and hydrogen plasma was fired into this using JXB emitters.  These emitters are modeled, along with the electron guns and trace air in the chamber. The post ends with a list of questions that need to be answered and appeal for funding.  Readers can download this and all other polywell posts on pdf from github.
 
“Complexity is the enemy of execution” – Tony Robbins

Part 1: A History of Cusped Systems

Introduction:
 
       Harold Grad was a huge math nerd.  He was a professor at NYU in the fifties and sixties [1, 2].  He specialized in applying advanced math to plasmas.  Plasma is a fluid; which also happens to conduct.  The math controlling it is a merger of the fluids equations (navier-stokes) and the electricity equations (Maxwell's equations).  The two combine to make a whole new field: Magnetohydrodynamics.  Harold probed the math; looking for any kind of plasma structure.



Cusps:

       Dr. Grads’ favorite geometry was the cusped system.  A cusp is a place where two magnetic fields sharply bend and repel one other [9]. One example is two north poles repelling.  Cusps are awesome because the plasma (mostly) leaks through the edges and apexes of cusps [41].  This shrinks the total area over which the plasma can be lost.  The plasma is contained in a trap with a few small holes.  Cusps have two major advantages. First, their fields are bent inward.  This is great.  Plasma tends to drift into bigger curved paths - so inward bending fields help to push material into the center [11].  That is helpful.  Second, cusps have a null point in the center.  The null point is a spot with no magnetic field.  It is a place where plasma can collect.  After Grad had shown the value of cusp geometry, other people latched onto this idea and a whole family of concepts were proposed [10]. 



"Free Boundary" Plasmas

       Cusp systems can shrink losses, but Harold Grad found a way to go further.  In some cases, the plasma can actually plug up the cusps [13].  Plasma is a moving soup of charged material.  Its' motion can make its' own magnetic field.  This can clash and reject the outside field.  This can lead to a plugged cusp.  Physically this is a diamagnetic plasma, rejecting the external field.  Inside, material can move about, free of the externally applied fields.  This system - theoretically - has a sharp boundary with a sheet of electrons moving on its' surface [13, 12, 15].  This is shown below.

Theoretically, this would be the world’s best plasma trap.  Not only is material better contained, but the plasma also loses less energy as light [9].  

The Lost Concept:

      Free boundary plasma would be awesome; but despite many attempts, the system was never demonstrated [13-15].  There are two good reasons for this.  First, high pressure plasmas are very hard to make.  Secondly, the effect is hard to measure.  By 1980, it had disappeared from most fusion programs.  Most teams moved on from the cusp geometries; looping the field lines to make a tokamak. That was situation - until 2014 – when EMC2 reported making a free boundary plasma.  It is still early days - but if the full potential of this discovery is realized – someone may win the Nobel Prize.

Part 2: The New Machine
 
      Sometimes better science comes from using better tools.  The new machine is far better than Bussards’ old WB6.  The electromagnets or rings were designed better.  The first change is its size; WB6 was much bigger.  Its’ rings filled six times more space [6,16].   The new machine is much slimmer, but more powerful.  This will lead to higher energy densities.  The devices are pictured below [3,4,16, 20].



The new model does not link the rings together.  They are mounted externally.  This leaves more space for plasma recirculation - something both Rider and Bussard stressed as critical [16-18].  Recirculation, means plasma can move without touching metal.  Recirculation is also used in the Lockheed Martin concept [41].  Mounting the rings externally also changes everything about how the rings are powered.  The old machine formed its’ electromagnets from one long wire.  This long wire, snaked its way through all six magnets and ran to one big set of 240 batteries [16].  This wire was over three thousand feet long, overheated and had three ohm of resistance.  The new machine broke the power supply up. Six distinct power supplies were used; nine batteries per ring.  This is much safer.  The wire also has a lower resistance.  A diagram of the power supply for one electromagnet is shown below.

This new system is more powerful.  The new design can reach energy densities at least three times higher in the center [appendix].  This is because the new rings are physically closer.  You can demonstrate this by comparing the magnetomotive force on the rings at full power.  This is the magnetic force that pushes the rings apart; they are like poles repelling one another.  In WB6, this force was roughly 37 newtons; in this new machine, the force is roughly 170 newtons [appendix].


Magnetic Geometry
 
      The rings are used to create a magnetic geometry.  The geometry is custom designed; specific for this application. A comparison of the energy density made by WB6 and this machine are shown below.



These plots show the density of energy for an empty system. Things would change, if plasma was in here.  The plots were made using a matlab code [19, 21].  Practically all of the energy comes from the magnetic field.  Electric fields do not make nearly as much energy density.  The reason for this comes from the fundamental electric and magnetic constants.  The new machine is clearly better.  The compact design lets this tool to cruise to an energy density one and a half times higher than Bussards’ old machine [appendix].  This new machine also makes the stronger field for less power.  This is also evident from the vector plots.  


These two plots compare the XY field of Bussards old WB6 and the new Navy machine.  The plot is made with the same parameters; so it is an apples to apples comparison.  Putting all this analysis together: it is clear that the new machine is plainly better.  It can produce a stronger containment more efficiently.
Part 3: Machine Inputs


Trapping Is All That Matters:

      The goal here, was not to build a polywell.  All they wanted was plasma trapping.  Hence, they do not care about: potential or composition.  The plasma could have been made of anything; that was not important, as long as it was trapped.  In this experiment, the plasma was made from vaporized plastics; with lots of carbon and hydrogen.  Simultaneously, charge on this plasma cloud did not matter. They did not care if more electrons, than ions were in there.  This also did not matter.  Electrons were used to take a “snapshot” of the trapped plasma.  The goal of this experiment was to demonstrate cusp confinement. 

        This is a big hairy experiment.  Aside from the rings and the vacuum chamber, there are a twelve other tools in play.  Three of these are used as inputs to the system; the rest measure something.  A list of these tools and where they are located, is shown below.

Two Plasma Emitters:

      It is tough to make a pressurized plasma.  Indeed, this is why cusp experiments have failed in the past [14, 2].  The team may have tried several things, before settling on the final plasma emitter.  The final tool may have seemed like overkill.  The plasma cannon flings vaporized carbon and hydrogen into the polywell.  They pulled this off by vaporizing a polypropylene sheet (imagine vaporizing a sheet of plastic wrap).  A picture of this tool is shown below.

       This design is brilliant.  At full power, it has one hundred and fifty thousand amps flowing along its’ outside [12].  These electrons move into the center and jump across the plastic sheet.  The high current vaporize the plastic; making a plasma of carbon and hydrogen.  Once across the gap, the current leaves.  It moves down the inner metal and out of the device.  As it leaves, it makes a magnetic field. The brilliance of this device, is that all these effects happen simultaneously: the plastic wrap is fully vaporized, an electric field forms across the gap and a magnetic field spins around the center.  When these effects combine, they fling a plasma outwards.  This happens because the plasma feels both the electric and magnetic field simultaneously; creating a drive force pointed towards the polywell. 

Modeling Plasma Emitters
 
       Modeling this emitter was not easy.  There are nine physical mechanisms that happen simultaneously.  I will spare you the math.  If you would like to dig into the numbers - you can see them all in this excel file.  All the effects that were modelled are shown below; effects are numbered in the order so you can follow along.



First, the current will not spark across the air gap [22, 23].  Electric arching can be modelled using Paschen law.  Paschen’s law tells us quickly that sparking will not happen.  That means that all the current must move through the plastic sheet.  This sheet has some electrical resistance.  We can model the resistance this using the equations for a circular sheet of polypropylene [25, 26].  This number allows us to find the electric field inside this sheet.  The field is plotted below.  As the current moves through, this sheet will vaporize and ionize.  This is because the energy needed to break the chemical bonds and fully ionize the plastic is only hundreds of joules [27-29].  Far more energy passes by.  So much energy that the sheet probably ionizes instantly.  It turns into a cloud of hydrogen and carbon ions.



       As the current leaves the plastic and moves down the cathode, it starts a new series of physical effects.  The current in the cathode creates a magnetic field.  This field can be modelled by treating the cathode like a big wire.  You can use the biot-savart law to model the field in a big wire [30].  The resulting magnetic field is plotted below.  The cathode has a huge amount of electrons passing through it – which will heat it up.  In fact, the metal likely reaches several hundred degrees kelvin [29, 31].  This causes the tungsten to chip away [2].  Overtime, the tungsten cathode degrades.  This process is known as thermionic emission.  It means that tungsten ions are also mixed into the plasma [32].



      This model tells us that there are electrons, carbon, hydrogen and tungsten ions in the plasma.  We need to know how much energy they have as they leave.  The emitter makes both an magnetic and electric field which hit the plasma.  With both fields in play, it creates a Lorentz force for all charged particles.  This is also known as the J X B force [24].  Anything that is positive is pushed outward.  This flings ions towards the rings.  Anything that is negative is forced backwards.  This pushes electrons back into the emitter.  Bear in mind, these emitters are really close to the rings.  They sit half a centimeter away.  The navy had to do it this way.  Unlike Bussard’s 2005 experiment - there is no electric field to steer the plasma.  The emitters are close, to catch all the particles before they spread out.  Before they are lost.  This experiment only used two injectors.  They could have had many more.  That is an important question for the next test.  What happens when we have many plasma injectors?  An overview of the equations used to model this system is shown below.  You can look at all the numbers in this excel file.

Electron Gun:
       Material does not only come from the two plasma emitters.  There is also an electron gun and trace air in the chamber.  The chamber had a couple of millitorr of gas left in it [22].  Some quick math (see excel file) shows us this only has a small effect.  Most of the plasma comes from the emitters.  An electron gun was also used.  Electrons were used to take a “snapshot” of the trapped plasma.  This was done using X-rays.  Electrons were released to make an “X-ray image” which could be read to show trapping.  This is very different from normal polywell experiments, where electrons are used to heat ions to fusion conditions.  A picture of the electron gun is shown below.



This electron gun was custom built by Heat Wave Laboratories in California [34].  It heats up a block of metal, to emit electrons.  These electrons are accelerated using a voltage and shot into the rings.  The metal is Lanthanum Hexaboride, a common electron emitter.  You can model emission using the Richardson-Dushman equation.  3.4E15 electrons emerge in the 180 microseconds of shot time.  These fly in at seven thousand electron volts of energy.     


Putting It All Together:
 
      All of these effects combine to make a plasma which is mostly hydrogen and carbon.  The remaining 6 percent is trace elements.  This includes tungsten, oxygen, nitrogen and the electrons.  Below is a summary of the plasma composition.  These amounts assume everything was injected instantly.


Conclusion: Lots to do with no funding


     This post lays out the groundwork for a study of the EMC2 paper.  So far, the science community has failed to scrutinize and explain this work.  There is so much to do. For example, there are roughly 200 papers on cusp confinement experiments and theory [1].  This body of work needs to be integrated and contrasted to the EMC2 paper.  Here is a list of the topics to address.   


1. Dose the EMC2 work agree with predictions?  Grad laid out what is needed to make this configuration stable [44].  Haines has spelled out how a plasma sheath may form in these geometries [15].  Dolan updated this work, summarizing the experiments that failed to see the effect [14].  We need to check the EMC2 tests against all of this.  Do their test conditions meet the old predictions?


2. What changed?  Why was this not seen before?  The test must have changed between EMC2 and past work.  It may turn out that previous teams fail to design the right experiments.  They may have missed the right measurement tools or designed for other outcomes.  

3.  What was the size of the sheath and the hole?  What is exciting about finding cusp confinement is it allows us to apply a backlog of theory.  Two parts of the geometry is the plasma sheath and sheath holes.  Several authors provide us with theory to predict the size of these sheaths and holes [35, 14].  These equations are shown below. They need to be applied to the EMC2 work. 



This containment method has so much potential.  If cusp confinement works, it could be a better plasma trap then: pinches, tokamaks, stellorators and magnetic mirrors.  In fact, it could trap better than any scheme with magnetized plasma.  That drastically changes what a fusion plant looks like.  It changes how soon we might expect one.  There should be millions set aside for this research and groups should be desperate to find qualified researchers for the work.  We could be looking at the best plasma trap in the world. 


Appendix:

2 Magneto-motive force:
 
     You can estimate the magnetomotive force between the rings by treating them like two circular magnets facing each other.  The equation for this is shown below.  Below this are the numbers used for WB6 and WB8.  The equations predicts 37.6 and 170 newtons for WB6 and WB8 respectively.



1 & 3 Comparing Energy Density:


      Developing a full magnetic model of the polywell took over six months of work.  The whole process is spelled out in: TakingA Stab At Simulation.  You can download the matlab and excel files used to develop the model from GitHub.  The model was benchmarked multiple times and in multiple ways.  The theory and mathematics is spelled out in reference nineteen.  The magnetic field inside the polywell can be modelled using the biot-savart law – specifically, it is a superposition of six electromagnets.  

        This tool was handy when comparing WB6 and WB8.  The starting point is equations that can be used to estimate the field at key points.  These points are the center, joint, axis and corner of the rings.  The equations are shown in older posts.  To do the math, you need the machines dimensions and the number ampturns in each ring [16,7].  Bussard’s old machine had between 20 and 800 thousand amp turns.  By contrast, WB8 had between 5 and 44.96 thousand per ring.  The results of these calculations are shown below.  The important point is that this new machine is one and a half times more powerful for the same number of ampturns, making it more efficient.  The real experiment measured a lower magnetic field then predicted by about quarter; this was verified by the experimental team [12,7].

Work Cited:
1.    Park, Jaeyoung. "Polywell Fusion: Electrostatic Fusion in a Magnetic Cusp." Microsoft Research. Microsoft Inc, 22 Jan. 2015. Web. 20 July 2015. 


2.    Park, Jaeyoung (12 June 2014). SPECIAL PLASMA SEMINAR: Measurement of Enhanced Cusp Confinement at High Beta (Speech). Plasma Physics Seminar. Department of Physics & Astronomy, University of California, Irvine: Energy Matter Conversion Corp (EMC2) url=http://www.physics.uci.edu/seminar/special-plasma-seminar-measurement-enhanced-cusp-confinement-high-beta


3.    "Polywell Fusion – Electric Fusion in a Magnetic Cusp" Jaeyoung Park, Friday, December 5, 2014 - 1:00pm to 2:00pm, Physics and Astronomy Building (PAB) Room 4-330, UCLA


4.    Talk at University of Wisconsin Madison, Monday, June 16, 2:30 PM room 106 ERB, Jaeyoung Park


5.    University of Maryland, Colloquium & Seminars, "Measurement of Enhanced Confinement at High Pressure Magnetic Cusp System", Jaeyoung Park, September 9th 2014


6.    "Polywell Fusion Electrostatic Fusion in a Magnetic Cusp", Jaeyoung Park, http://fire.pppl.gov/FPA14_IECM_EMC2_Park.pdf, Tuesday December 16, 2014 Hyatt Regency Capitol Hill 400 New Jersey Avenue NW, Washington, DC 20001


7.    Private conversation, Jaeyoung Park, April 2015


8.    Linden, Tomas. "Compact Fusion Reactors." CERN Talks. CERN, 25 Mar. 2015. Web. 20 July 2015


9.    J. L. Tuck, A new plasma confinement geometry, Nature (London) 187, 863 (1960).


10.    Berkowitz, J., K.o. Friedrichs, H. Goertzel, H. Grad, J. Killeen, and E. Rubin. "Cusped Geometries." Journal of Nuclear Energy (1954) 7.3-4 (1958): 292-93. Web. 16 June 2014.


11.    McMillan, Brian. "Lecture 8, Slide 20." PX438 Physics of Fusion Power. The University of Warwick, 13 Feb. 2013. Web. 04 Apr. 2013.


12.    Park, Jaeyoung, Nicholas A. Krall, and Paul E. Sieck. "High Energy Electron Confinement in a Magnetic Cusp Configuration." In Submission (2014): 1-12. Http://arxiv.org. Web. 13 June 2014.


13.    Grad, Harold. "Plasma Trapping in Cusped Geometries." Physical Review Letters 4.5 (1960): 222-23.


14.    Haines, M. g. "Plasma Containment in Cusp-shaped Magnetic Fields." Nuclear Fusion 17.4 (1977): 811-58. Web. 18 June 2014.


15.    Dolan, Thomas J. “Review Article: Magnetic Electrostatic Plasma Confinement.” Vol. 1539-1593. N.p.: Plasma Physics and Controlled Fusion, 1994. Print.


16.    Bussard, Robert W. "The Advent of Clean Nuclear Fusion: Superperformance Space Power and Propulsion." 57th International Astronautical Congress (2006)


17.    Rider, Todd H. "A General Critique of Inertial-electrostatic Confinement Fusion Systems." Physics of Plasmas 6.2 (1995): 1853-872. Print.


18.    Rider, Todd H. "Fundamental Limitations on Plasma Fusion Systems Not in Thermodynamic Equilibrium." MIT Thesis 1995.


19.    Carr, Matthew, and David Gummersall. "Low Beta Confinement in a Polywell Modeled with Conventional Point Cusp Theories." Physics of Plasmas 18.112501 (2011): n. page. Print


20.    Duncan, Mark, and Robert Bussard. Should Google Go Nuclear? (Summary). N.d. MS. Should Google Go Nuclear? Www.askmar.com. Mark Duncan, 24 Dec. 2008. Web. 4 Feb. 2013.


21.    Moynihan, Matthew. "Taking A Stab At Simulation." The Polywell Blog. N.p., 6 Feb. 2013. Web. 27 June 2015.


22.    Private communication, “What was roughly the pressure inside the machine?” Paul Sieck, July 2, 2015 


23.    Lieberman, Michael A.; Lichtenberg, Allan J. (2005). Principles of plasma discharges and materials processing (2nd ed.). Hoboken, N.J.: Wiley-Interscience. 546. ISBN 978-0471005773. OCLC 59760348


24.    Thoma, C., D. R. Welch, and T. P. Hughes. "Ballistic and Snowplow Regimes in J×B Plasma Acceleration." Physics of Plasmas Phys. Plasmas 16.3 (2009): 032103. Web.


25.    "How Do You Model the Resistance across a Symmetric Sheet of Plastic, Stretched (think Cernan Wrap) between a Circular Anode and Cathode?" Electricity. Physics Stack Exchange, 13 July 2015. Web. 20 July 2015


26.    "Polypropylene Material Information." Polypropylene. Goodfellow, 2015. Web. 20 July 2015.


27.    "Ionization Energies of the Elements." Wikipedia. Wikimedia Foundation, n.d. Web. 20 July 2015.


28.    "Bond Energies." Chemwiki. University of California Davis, n.d. Web. 20 July 2015.


29.    "Joule Heating." Wikipedia. Wikimedia Foundation, n.d. Web. 20 July 2015.


30.    NAVE, R. "Biot-Savart Law." Biot-Savart Law. Georgia State University, n.d. Web. 20 July 2015.


31.    "The Physical Properties of Tungsten." Wikipedia. Wikimedia Foundation, Web. 20 July 2015.


32.    Harbaugh, W. E. "Tungsten Thorinated-Tungsten and Thoria Emitters." (n.d.): n. pag. Web. 20 July 2015.


33.    Gunther, Kim. "Model 106381 Electron Gun for Plasma/Fusion Research." Heat Wave Labs Inc. Heat Wave Labs Inc., n.d. Web. 20 July 2015.


34.    "The Trapped Plasma Volume." Interview by Jaeyoung Park. Private Communication 24 Aug. 2015


35.    Kitsunezaki, Akio. "Cusp Confinement of High-beta Plasmas Produced by a Laser Pulse from a Freely-falling Deuterium Ice Pellet." Physics of Fluids Phys. Fluids 17.10 (1974): 1895. Web.


36.    Mare, Indrek. "Cube Polywell Wiffleball Modeling Using Method of Images." http://www.mare.ee/indrek/ephi/images.pdf Indrek's Homepage. Indrek Mare, 2008. Web. 31 Aug. 2015.


37.    "Question." Message to John Santarius. 17 Aug. 2015. E-mail.


38.    Carr, Matthew, David Gummersall, Scott Cornish, and Joe Khachan. "Low Beta Confinement in a Polywell Modelled with Conventional Point Cusp Theories." Physics of Plasmas Phys. Plasmas 18.11 (2011): 112501. Web.


39.    "An Interview With Thomas Ligon on The Polywell." Interview by Thomas Ligon. YouTube. YouTube, 25 May 2009. Web. 31 Aug. 2010.


40.    Engelhardt, W. "Is a Plasma Diamagnetic?" Physics Essays 18.4 (2005): 504-13. Web.


41.    McGuire, Thomas. "The Lockheed Martin Compact Fusion Reactor." Thursday Colloquium. Princeton University, Princeton. 6 Aug. 2015. Lecture.


42.    Tuszewski, M. "Field Reversed Configurations." Nucl. Fusion Nuclear Fusion 28.11 (1988): 2033-092. Web.


43.    Park, J. "High-Energy Electron Confinement in a Magnetic Cusp Configuration." Physical Review X. N.p., 11 June 2015. Web. 06 Nov. 2015.


44.    Berkowitz, H. H Grad, H Rubin "Magnetohydrodynamic Stability." Journal of Nuclear Energy P/376 (1954): 177-89. Web. 7 Nov. 2015.


45.    Private conversation with Dr. Joel Rogers. 30 Sept. 2014.