Sunday, December 10, 2017

Notes On The VLAB Fusion Event


On Tuesday November 7th 2017 a fusion panel discussion was held on Stanford’s campus.  The panel was organized by Virtual Labs, a non-for-profit organization in Silicon Valley. The goal of VLAB is connect entrepreneurs to technologists.  Former members of the VLAB group have included managers at some of the valleys’ premier technology companies.  The event was organized by Michelle Tsing, a lawyer and an entrepreneur.  The panel was moderated by Dr. Rachel Slaybaugh a member of nuclear engineering department at Berkeley.  The panel also included Dr. Michele Lebarge from General Fusion, Dr. Thomas McGuire from Lockheed Martin and Ray Rothrock, a former member of Venrock capital.  It also included Dr. Matt Thompson from TA Technologies (Tri alpha rebranded, more on this later).  I reached out to Michelle and she was gracious enough to share a 90 minute recording of the panel.  You can watch the event through facebook - here.  After watching this talk, I wrote this quick summary of the event.  Enjoy. 

Dr. Rachel Slaybaugh (Moderator):

Slaybaugh opened the discussion with a quick take on fusion. Her style was very positive - despite a somewhat tough crowd. One issue was the triple product Dr. Slaybaugh mentions at the start of the talk. Though it is a common metric used to measure fusion but I think it is a bad metric for a commercial plant. A better metric is the energy balance for a plasma-based approach. This equation was laid out by John Lawson in 1956. That eventually became the Lawson criteria, but I argue it is much more instructive to look at his original energy balance.

Each one of these terms points towards key design principal. Fusion rate has been the focus of the last several decades. We drove up fusion rates, with little consideration to other parameters like cost, efficiency and scale. Conduction is the loss of mass from the plasma (and the energy that leaves with it). Here, metal surfaces are the enemy -- and containment is the goal. I have seen chambers built out of glass to stave off conduction losses. Radiation is all the energy that leaves as light (X-ray, IR, UV, visible, ect). Not a lot of opportunity to innovate here – tuning plasma and light reflection are two ideas that have been kicking around for years. Finally, efficiency is probably the most unexplored topic in fusion research. I would put advances in superconductors, direct conversion and capacitors as all improvements in machine efficiency. Below is a chart on purposed fusion approaches. Note that this chart is (1) incomplete and (2) contains ideas that may not work.

Dr. Matthew Thompson (TA Technologies): 

Dr. Thompson was a very polished speaker. Of the group, his view point feels the most detached from science. He is not there to talk experimental physics; he wants to talk about electricity on the grid. It is as if the fusion problem has already been solved. That is some serious confidence from an organization that just rebranded. Why did Tri Alpha rebrand? Weirdly, it was to move out of the energy space. Tri Alpha has created some of the strongest particle beam sources in the world. The beams are very small and can create 1,000,000 electron-volt particles. Those specs alone to get the market interested – those beams are probably superior to the ones used on ITER. Each beam has two parts: a particle source and an accelerator. Tri Alpha also plans to use those particle sources and make a cancer product. Ions from those sources can be fused. This makes neutrons. Those neutrons can be used in cancer treatments.

This past week the CEO of Tri Alpha laid out a vision for this new product – one of which has already been sold. The product, a machine about the size and cost of an MRI machine, will be used in boron neutron capture therapy. Basically, boron is sent into cancer cells inside the human body. Neutrons are then passed through. The boron absorbs the neutrons and atomically splits. When it does, it acts like a tiny bomb, killing the cancer cell. This company can make these neutrons from a fusion reaction. By selling a commercial machine to do so TAE has likely become one of the first companies to connect fusion into the medical space. How much will this side effort affect Tri Alpha core mission? One cannot criticize the company for trying to turn a profit. Making money, makes the company permanent. Thompson finished his talk with a video on the history of the company. The images presented were a rare insight into company history. For the first 10+ years of this firm, everything was so secretive. They were notorious for this. The company did not even have a website for the first 10 years.

Dr. Thomas McGuire (Lockheed-Martin): 

Of all the groups, we know the very least about Lockheeds’ effort. Unlike everyone else, they have not published. Everything Tom McGuire said added some new knowledge to this approach. For example:

Size: The Lockheed team has now expanded to 25 people. This is a great sign. The results have likely been very promising.

Speed: McGuire estimated that his team iterates every year. Great. Only a small team could move that fast.

Fuel: Lockheed is planning to put tritium in their feed stock. This will add NRC and EPA regulations to their effort. Where I got my PhD it took a team of a couple dozen professionals, several million dollars and several years to create a tritium handling system.

Design: McGuire laid out a neutron blanket around the device. There are issues associated with a lead-lithium blanket and ironically General Fusion is the world leader in that technology. The blanket is baked into General Fusions’ approach.

Runtime: McGuire describes a machine that is self-sustaining: “…Like a fire, it will keep burning, but you need to continually add fuel...” Today, there are fusors that can do fusion like this. I am skeptical of this claim; it feels premature. In this article, I have written extensively on Lockheeds’ approach. It would be interesting to extend this analysis to look at runtime.

Future: When he looks forward, McGuire is envisioning an effort that would probably be too big for Lockheeds’ management. “…This is going to get bigger with each experiment, turning into an organization and technology similar to Tri Alpha Energy…” How would Lockheed manage such a large organization? Would they need to spin out this out into a new company?

McGuire has gotten much better at pitching. In May of last year, he spoke on a panel at the Milken Global Institute. I wrote a review of that panel discussion here. Having watched both, I can say his style has improved greatly. His answers are clearer and more succinct. I also liked his comparison between his cusp confined plasma and a mosh pit. Excellent comparison.

That said, it is painful to hear him talk about putting fusion an airplane. His reactor weight is estimated to be between 200 to 1000 metric tons, with its’ blanket. This means this reactor may in fact be heavier than a 747 airplane. How could any airplane lift such an object?

Ray Rothrock:

Ray Rothrock worked as nuclear engineer before heading to Silicon Valley to become a very famous venture capitalist. He was critical in helping Tri Alpha Energy secure funding from Venrock capital. Ray retired from Venrock in 2013. Through his use of resources and conn
ections, Mr. Rothrock has done more than many people to push nuclear. . He also funded Pandora’s Promise, an ideological movie supporting nuclear power. Mr. Rothrock also pushed the Department of Energy to pay attention to new nuclear. “… [the DOE] did not believe that there were 50 nuclear startups out there; they asked me to put them on the phone with some…” These actions created the Gateways for Accelerated Innovations in Nuclear (GAIN) program. GAIN has initiated several efforts into gas and molten salt reactors. Could Mr. Rothrock do the same for fusion power?

Dr. Michel Laberge (General Fusion): 

Overall, Dr. Laberge is probably one of the strongest pitchmen in fusion right now. He is relatable. A passionate, technical guy with a touch of goofiness in him. His style is very good and remained unchanged for many years. In his talk, Dr. Laberge offered some insight into pitching fusion that should be mirrored by others. General Fusions’ pitching strategy relies on de-risking capital. Their goal is to get the technology to a point where it can be acquired by a bigger company or secure more funding. It is at the moment of acquisition, that their investors see returns on their investment. The company does this on a 6 to 7 year cycle, fixed by milestones. Dr. Laberge says: “…this is how we get away from the idea that fusion is a little long…” Currently, Dr. Laberge is chasing a 300 million dollar investment for his next big machine. This sounds ominous. Scaling up is always a bad sign, unless the current machine has yielded some excellent results.

The questions and answers 

How do you keep your organization focused?

Everyone agreed this was a hard challenge. Ray Rothrock argued that the VC actually have the hardest role in keeping fusion folks on task. The money men tell the researchers they cannot follow any side projects. In contrast, Dr. Laberge says he has to fight his board to keep the focus on fusion and not spin-offs. Dr. McGuire says his team drives the focus “we really do not want to do the same thing for 20 years.”

How much of your effort is dedicated to simulations?

Any good fusion effort has a theory/simulation team as well as an experimental team. Of the three of these, the prototype is king. However, simulations will go over very well in Silicon Valley. That community knows high power computing very well. Simulations are supposed to be scouts for any fusion organization, mapping out an unknown operating space. General Fusion stated they had a quarter of their scientists are doing simulations. But these simulations were really only looking at only small parts of the machine.

How do use outside review teams?

Ray Rothrock had the best answer for this. He describes an evolving processing, where outside review panels are brought in as needed. The first panels are always all scientists. But as the company learns, its’ needs change. The second panel includes engineers and material scientists and from there business experts are brought in. “…if you don’t know, the first approximation for the cost of a power plant is the amount of copper, steel and concrete you use…” Dr. McGuire said that his review team actually helped him. They found the minimum reactor size at which they could understand the plasma.

How do you pitch? How do you hire? Everyone agreed that there was no shortage of motivated employees. Dr. McGuire described an entirely internal funding model which was totally milestone based. Tom has to pitch to the Lockheed leadership. “… What really seems to resonate is the risk versus our milestones, so we don’t have a set time… but we have an idea of the steps we have to take and what it means when we get to each step…”

Ray said a VC partnership lasts 10 years at most – but Rothrock sold this investment on a 20 year timespan. Ray also pushed the idea of adapting the biopharmaceutical investing.

How does this effort compare with China? 

At the 2016 and 2017 FPA conference, Dr. Yican Wu (head of the INEST office) gave a nice overview of China’s fusion/fission research. INEST is an office at the Chinese Academy of Sciences and would be equivalent to a very small national lab. He said that INEST has a staff of 500 PhDs, and that their average age was 31. In another talk, Dr. Baonian Wan (director institute of plasma physics, China Academy of Sciences) gave an estimate on Chinas’ investment in fusion. He estimated their budget at 2.5 billion yen (about 377 million dollars) per year, for the next 5 years. This fusion budget was worked into the latest 5 year plan in China.

INEST had wide interests. In fission, they were looking at molten salt reactors. In fusion – the Chinese were building a mirror machine. The US has no mirror program; that was abandoned years ago. China is likely doing this to mimic the Gas Dynamic Trap mirror machine in Russia. China also has a very high powered neutron source for materials testing. China is also working directly on the thermal blanket technology – this is another area where the US is not funding the research. The world leader in blanket technology is still General Fusion, a Canadian company. Still, much of Chinas’ work was focused on ITER.

What about Fusion in Nanotubes?

I once did a survey of a fusion web forum and found many people speculating about fusion in combination with some other cutting edge idea. This seems very common.

Which Approaches are pulsed? Which are continuous?

Dr. LeBarge describes General Fusion’s final machine as a 200 MW pulsed machine. Both Lockheed and TA Technologies are going continuous. A pulsed system at 1 hertz that would generate 100 gigajoules with each shot. This energy would be recycled, lost and emerge from the power plant as 200 MW of electricity. A plant of that size would be akin to a small combined cycle natural gas plant. CC Natural Gas has been very popular in the past 10 years. Those plants are relatively cheap, run on cheap feedstock and are just the right size to meet power needs in Asia. GF plant would be much smaller than a conventional fission core.

Can Fusion Ramp?

Probably. In most cases, you could store any excess energy (from pulsing) and then meter it out in a ramp. But, it depends on which approach ends up hitting net power. For example, in laser fusion (inertial confinement fusion) the "ramping" depends on how often they can shoot the target. Here is a summary of the ramps for different fusion approaches:
  • Fast ignition or direct drive, right now the best is ~45 minutes on the Omega laser system. 
  • Indirect drive: you are talking NIF where shots likely take several hours between each other. 
  • Heavy ion beam ICF: the shot time likely shrinks to seconds (ion beams are a more established technology). But ion beam ICF may not work, they are not as mature a technology. 
  • Magnetized Target Fusion: General Fusions' approach is a cross between an ICF-like compression with pistons and compact torus (think self-sustaining, spinning plasma apple). General Fusion would likely ramp by shot rate.
  • Plasma Liner Experiment at Los Alamos would also ramp by rep rate. 
If you are talking tokamaks, spherical tokamaks, stellarators, and the like you see mixed performance in run-time and temperature. You could "ramp" by raising or lowering the ion concentration inside the machine - but your somewhat limited because you have operating windows. For example, tokamaks run best in "H-Mode" and you need target temperatures, pressures and densities to hit that. You could also ramp, by pulsing these machines; here are some run times:
  • Spherical Tokamaks: The longest run time I have seen was ~26 hours by Tokamak Energy. But, their temperature and density was low. 
  • Dynomak: This approach looks to be finicky - so very limited in operating space. You would likely ramp by pulsing. 
If you are talking pinches, they would also ramp by controlling their pulsing. There are several types of pinches, pinch-hybrids and exotic pinches. These include:
  • Focus fusion: I don't know anything about this. 
  • Screw pinch: theta pinch and Z-Pinch all are short pulsed machines (pico and nano second run times). These were some of the first fusion machines and in (my opinion) these have a low chance of going commercial. 
  • MAGLIF is a combination of pinch and laser compression. This is also pulsed, but you need to wait tens of minutes between shots, because a laser is used and the lens need to cool down. 
  • Levitating Dipole Experiment I call this an exotic "gentle pinch" for plasma. They fused for like 10 - 20 seconds. Even though MIT showed they could run the machine for 7-8 hours, they did not get the funding to really try. 
If we did magnetic mirrors, like the gas dynamic trap or machines like The Mirror Experiment (TMX) we are taking pulses in the milliseconds, up to seconds. It is unclear if mirrors could ramp. Ken Fowler, Ralph Moir and Thomas Simeon recently published a paper arguing we should re-start mirrors.

So in conclusion, ramping in fusion could be done by:
  • Controlling rep time (most common method) 
  • Energy storage for re-metering later (less common)
  • Changing the ion concentration (rare) 
  • Changing the operating window (rarest) 
Whichever method we use, will depend on which technology wins.

Sunday, November 26, 2017

The Current State Of US Fusion


In November, I got a call from a podcaster.  His name was Gabe.  He was curious about fusion.  Gabe “…want to do an energy show and contrast fusion with new fission.  I honestly know very little about it…”  Questions were sent along and I spent a weekend researching a reply.  

Fusion is heating up.  Activity and interest has been steadily rising over the past fall.  Yes, ITER keeps on rolling - but a lot of people are looking elsewhere.  Since September, I have personally heard of several new small efforts, a new lobbying group and two new investor forums [49 - 52, 34, 35]. 

But, where is all of this heading?  Will these folks still be here in 5 years?  Have we seen the winning technology already?  The answers to these questions are still unclear.  What is clear is the need to remain scientifically accurate.  If you see a technical error, please reach out.  As Warren Buffet famously says: “be fearful when others are greedy”.  When others get enthusiastic, technical people should stay conservative.   

I cannot say when fusion power will come.  I can say that there are a lot of ambitious, intelligent people aiming to try.  Moreover, there are lots of ideas that have not yet been tested.  And, there are investors looking to make big waves.  Exciting.  These next few years should be damn exciting.  Hope you stick around.

Could you give us a synopsis of where fusion power research is at and where it is going?

US Fusion Budget:

The US fusion budget last year was 951 million dollars [1].  For comparison NASAs’ budget was eight billion [2].  I argue that the current fusion budget is very low and lopsided.  It is lopsided because it focuses only on two approaches - which we know will not become commercial.  It is low, because this budget gives us no space for anything new.  Sadly, this has been the state of things for about the last 20 years or so.  Below is a plot of the US fusion budget. 

Laser fusion (ICF):

The US fusion budget gets split in half.   Half of the money is sent out to support laser fusion and related technologies.  The main goal of that money is to maintain the status quo.  It holds up activity at the national labs, a few companies and a few universities.  Laser fusion is where you take a small ball of ice and you blast it.  The ball of ice is frozen radioactive hydrogen.  The beams attack from multiple (60 or 192) directions and squash the fuel [3, 4].  When the beams hit the ice surface, there is an explosion of energy outwards and an equal and opposite compression wave inwards.  This compresses the fuel to a temperature and pressure where fusion can occur.  For example, a typical temperature could be between 10 and 15 million degrees kelvin and the pressure is 1000x the density of water [3, 4].  A typical implosion would last about 20 nanoseconds.  

This laser approach to fusion is over sixty years old [5].  For the first ten years it was classified by the US government.  The effort became public in 1972 [6].  Since then we have built a couple dozens of these kinds of machines.  The government likes this approach because aside from doing fusion you can replicate the environment inside a nuclear bomb.  I spent six years working on this fusion approach.  My doctorate was on developing these ice balls – known as targets - trying to find ways to create them in a cheaper way.

A picture of the National Ignition Facility – a very expensive ICF system.

The biggest laser facility in the world is the National Ignition Facility. This machine was built at Livermore National Labs. Construction started in 1997 and it took them 12 years to build. The thing cost 3.8 billion dollars and was first turned on in 2009 [3]. The key idea behind NIF was getting something called ignition. Ignition is a fusion chain reaction. You get 1 fusion event, and that creates another, and another, and another. That is a big deal - if you can make it to work. 

Well, in 2016, the Department Of Energy admitted that NIF will never ignite [7]. That was a big deal. What it means is that laser fusion is probably not going to work as a power plant approach. You cannot get enough energy out of the machine to overcome the huge energy you put in. NIF is probably somewhere between 3 and 0.5% efficient [8]. Moreover, this is a major defeat more than just one approach. There is a whole family of laser fusion-like approaches that are very closely related. Some concepts include: direct drive, indirect drive, ion drive fusion and fast ignition [9, 3, 4, 10]. All of these ideas suffered with NIFs’ failure to get ignition.

So bottom line: we are spending 440 million on a spectrum of groups, companies and universities following an approach that we know will never work. It will not work energy-wise nor will it work commercially. That may have been fine when there were no other fusion approaches available to us – but that is no longer true.

The rest of the US fusion budget goes to a family of magnetic schemes surrounding the tokamak.  A tokamak is basically a racetrack.  If the ions are the cars, then the course is set by the magnetic fields.  The ions race around, and around, the ring.  Hopefully they bump into one another at high speeds.  When they do this, they can fuse. 

The tokamak is the world-wide fusion research heavyweight.  Over 220 tokamaks have been built, planned or decommissioned since this field got started [11].  Today, we are reaching a point where 80% of all the fusion researchers in the world - are all tokamak people.  That is a problem.  The program directors, the reviewers and the university professors are mainly looking at fusion through the lens of a tokamak; through the physics of a tokamak.  This means they have a mostly hazy understanding of other approaches.
Not to say that tokamaks have not worked well.  For example, the world record for the longest running tokamak is 26 hours.  That was set by a startup in England [12].  

Technically, the world record for energy extraction, in fusion, is held by a tokamak.   The record was set by a machine called JET, in England in the late nineties.  That record?  23 percent.  That machine took 100 megawatts to run [48] and it pulled 23 megawatts out of the plasma.   It is worth pointing out that the JET team claimed a much higher efficiency.  But, they were playing math games (NIF did the same thing in 2014).  They used the energy on plasma as their starting point – not the real input numbers.  Finally, a good example of a typical tokamak performance was set by China.  They ran their machine for 102 seconds at 50 million degrees [13].  That is considered very strong showing in the tokamak world.

A picture of the ITER site.

Right now, the world is building a huge tokamak in France, called ITER. This project is the focus of most of the US fusion effort. ITER work is being done in many states across the US. Multiple companies, organizations and universities are involved. Ultimately, we don’t know how much this is going to cost, but estimates range from 16, 21 and even 50 billion dollars [14 - 17]. Currently ITER is 7 years delayed [18]. I suspect that it will be NIF all over again. They will finish it. It may work - or it may fail physically - but it will never work commercially. I doubt it will produce more energy than we put in it. We heard this same story for 12 years with NIF – and that machine failed. There are basic flaws with these huge machines. It takes so long to build them - that innovations cannot be added as construction occurs. They are also very complex – hiding problems within the technical details. They also rely on models that can make assumptions that turn out to fail. That said ITER will drive technology into the greater economy – even if it fails.

US Fusion Funding Problems:

The problem with the US funding system is that you cannot get anything new added. Oh sure, you can get seed money. Most teams will get that. I have seen this story play out so many times - it has become a cliché. Here is how it works:

1. A professor or a team comes up with a good idea.  
2. They publish.  They get a small (100K to 500K) grant. 
3. They run a lab for 5 to 10 years.  They makes huge strides.
4. They get to a point where they need 1 to 5 million in funding.
5. Their funding gets killed support existing approach (NIF or ITER).  Idea dies. 

This has happened time and time again. It is still happening now. Here are some (rough) examples from the past 20 years. Note there are examples for concepts further back.

  • The Levitating Dipole Experiment at MIT from 1998 – 2011. This was run by Dr. Jay Kesner and Dr. Micheal Manual [19]. The team was gearing up for ignition experiments when funding was cut - for ITER - in 2011. 
  • The Dynomak at the University Of Washington, run by Dr. Tom Jarboe. In 2011, the group found a great way to heat plasma. This opened up a whole new approach to spheromaks [20]. They could not get the funding and so went private. 
  • The POPS machine proposed by Dr. Park and a team at Los Alamos in 1998 [21]. This concept played games with ion oscillations to avoid the fusor grid.
  • The penning trap concept pushed by Dr. Dan Barnes (LANL) late nineties. Dr. Barnes wanted to trap a mostly negative plasma inside a penning trap and get the ions to accelerate using the created voltage drop [23].
  • A multiple ion beam approach pushed by Dr. Ray Sedwick at the University of Maryland in 2011. This approach has some fundamental charge limitations and instabilities – but Ray was able to get pretty far with it [22]. 
  • The Plasma Liner Experiment pushed by Dr. Hsu at Los Alamos and by Dr. Doug Witherspoon at HyperV Inc. This concept used converging plasma beams to squash plasma together. This has been around since the early 2000’s.
  • The Field Reversed Configuration work done at the Redmond Plasma Physics Lab in Seattle. This group existed through the nineties and was run by Dr. Alan Hoffman & Dr. John Slough [25]. When they could not get any more DOE funding, they formed two private companies. 
  • The Princeton Field Reversed Configuration. Dr. Sam Cohen at PPPL set a world record for the longest stable FRC ever created by mankind [26] but he runs his lab on less than 200k a year. This year, the DOE ended their funding (to support ITER) and they had to go through NASA and the Army.

One example of a new fusion concept.  The University of Maryland modeled this approach, but this failed because of space charge limitations, problems with ions flying apart (beam-beam instabilities) and problems at the turning radius [26, 27].  This approach attempted to amplify a natural ion-ion beam bunching effect.  It borrowed innovations from the field of mass spectroscopy.

In fact, in the 60 years since we first demonstrated controlled fusion, there have been many ideas put forward to turn it into a power plant.  In the chart below, I lay out these ideas.  I have grouped them together by approach.  Even this list is probably incomplete.  Recently Dr. Ralph Moir has suggested several improvements to this chart [A-FF].  Bottom line: our current US funding system is great at maintaining the “fusion status quo” but sucks at adding anything new.

A New System:

If we ever want to get to a commercial plant - we need a new funding system. The US should adopt a system similar to the one used in pharmaceutical companies. Drug companies have a pipeline. They give a bunch of high risk drugs a very small amount of money. These could fail. So they support many concepts – but keep things cheap. A good amount might be a million a concept. That is typically more than most teams survive on. A second tier should be supported at the 10 to 30 million dollar range. You could support maybe ten concepts there. These are more mature designs. Finally, there should be three big efforts that should be funded at the 100 to 150 million range. This way you could incorporate your existing efforts, while adding in new ideas. For example, ITER and NIF could get 100 to 150 million per year in this system. But you could add a new big machine, like a national FRC.

Critically, you must build this system around going commercial. The money must be tied to this. Right now, all we care about in fusion is something called a triple product. That is the density x temperature x trapping time of a machine. This is a terrible meter stick. By that definition NIF is a great machine – even though it costs 3.8 billion and failed to get ignition.

We should care about a machines: run time, cost, efficiency, energy in/energy out and size. Groups must to prove they are making progress along these lines - to move up or down in funding. Below is a quick graphic I threw together on this. Finally, it would be nice to try to fund with public-private partnerships. Use public money to try to lure private investors. There are some interesting co-ownership models you could pursue. For example you could have a privately run group applying for public funds through block grants.

Amateur Fusion:

Since 2000, fusion has been moving in new directions, which I think are worth watching.  These are outside of the federal system.  New innovations have come from two groups: amateurs and venture capitalists.  I will start with the amateurs.  The first private citizen to build a fusion machine was a guy named Richard Hull.   He was living in Richmond Virginia and in 1999, Richard built a small fusor in a shed behind his house.  He got fusion.  This was a pivotal moment in the history of fusion – and almost no one noticed.  It paved the way for people to start doing fusion in their homes. A fusor uses an electric field to heat ions to fusion conditions.  Typically you need between 10 and 110 thousand volts to make them work.  They have a big metal cage in the center.  This sucks away mass and energy from the device.  Typically the losses are 10,000 to 1.  Meaning, for every unit of energy of fusion we make we are losing about 10,000 to that wire cage [38].

Since 1999, amateur fusion has grown significantly. About 90 people in North America have built small fusors in their homes and garages. Some are just middle school kids. Jamie Edwards is one example. He fused the atom at 14, in his middle school, for about 2,000 dollars. They had him on The David Letterman Show a few years ago. I mean, when a 14 year old can fuse the atom in his school, the world needs wake up the heck up and realize that something big is happening here. Fusors work. They can run continuously. I have heard it said that you could run one for days without a problem (though I have never seen it done). In 2015, we even had an amateur claim that he got 1E11 fusion reactions per second on a 100 watts of input in a fusor [37]. That is about 100x better than a typical fusor, but not strong enough to get excited yet [38].

We have now seen amateurs build other devices, other than fusors.  To be clear: none of these machines have gotten any fusion yet.  But, we have seen an amateur field reversed configurations [36], amateur spindle cusps [34] and I know of one group trying to build an amateur compact stellorator [35].  These are all unique fusion machines – devices we’ve never seen outside of university labs – being built by hobbyists.   The reason for all of this is pretty simple.   Amateurs can do this now because of superconductors.  That technology has now reached a point where you can get a strong field, for a reasonable price and a small electrical energy.  In the case of high temperature magnets, you can run them at reasonably cold temperature using liquid nitrogen.  Often times, these kids can get the stuff they need for free.  The companies are willing to hand over the magnets for free.

Venture Capital:

The other group to watch is in fusion are the Silicon Valley folks.  There are about a dozen startups who are explicitly chasing a fusion concepts.  They maybe have 2 to 3 hundred employees between all these companies [39].  The two biggest ones are General Fusion and Tri Alpha Energy.  Between them, they have raised about a billion dollars in private capital.  General Fusion was founded in 2002 in Vancouver Canada.  Their approach involves getting a plasma donut into a spinning bath of lead-lithium and compressing the fluid around it.  They have raised money from famous investors like Jeff Bezsos.  The company has been making a lot of headway both technically and publicly.  That said, I was disappointed in the latest results they shared at the ARPA-E meeting in August [40].  As I understand it, they want to scale to a bigger machine, which I see as a bad sign.

The other big company is Tri Alpha Energy, which has a partnership with Google [42].  The company has gotten funding from Peter Theil and Steve Balmer from Microsoft.  This company dates back to 1998 and it has an approach based on the field reversed configuration [41].  The FRC is a self-sustaining plasma donut.  The plasma moves in a loop.  That movement makes a magnetic field.  That field self-sustains the donut.  The FRC is an example of a self-organized plasma.  I think self-organized plasmas are the direction this whole field needs to move in.  The FRC is great.  The problem with it is stability.  The loop slows, and flies apart.  Tri Alpha has to keep its’ plasma spinning by hitting it with particle beams along its’ surface.  Like the old game of the hoop and the stick.  Last I heard, they were able to keep the donut spinning for 11 milliseconds [43].  That might not sound like a long time, but this was kept moving for the lifetime of the machine. Meaning if they build a machine that can run for 2 hours, they may get 2 hours of fusion.

Behind these two big companies, there are about a dozen smaller groups.  I like CT fusion from the University of Washington.  I like EMC2 which just did some groundbreaking simulations on the polywell.  I also like Lockheed Martin’s CFR machine, but I urge them to publish.  I also think Tokamak Energy is doing very well.  There are more groups that need to be watched. 

Fusion, On The Market

Finally, I want to mention that there is now a commercial product on the market that uses fusion.  For a bit over a million dollars, you can buy a neutron generator from a company called Phoenix Nuclear Labs [45].  Neutron generators based on fusion are not new.  We first saw them on the market back in 2000, from a company called NSD-Gradel.   But this PNL machine is light years ahead of where they were.  The device can produce 1E+11 neutrons per second, for over 130 hours continuously [44].  Along with another company, PNL is gearing up to use these devices to mass manufacture medical isotopes.  That market is about 1 billion dollars a year worldwide, and these companies are going to crush it.  They signed a 110 million dollar deal with GE Health care and a distribution deal with Chinas’ largest pharmaceutical company [45].  In August, Shine broke ground on a new facility to manufacture these isotopes [45].

I’ve heard it said that fusion power has the potential to give us limitless free energy one day.  In your opinion, how likely is that to happen and how far off might that be?

The milestone in front of everyone is net power.  That is like that first lift off at Kitty Hawk.  No one has done it yet.  Not in sixty years.  Not anywhere in the world.  We have known since 1956 what it will take to get there.  A British man named John Lawson is too thank for that.  In 1956, John worked out the energy balance for any plasma-based fusion device [28].  Here it is below. 

All you got to do is build a machine to beat this equation and you’ve made history.  Net could mean 101 watts out of a 100 watt input.  All it means is more energy out than you put in.  I have written extensively about each term in this equation, and what kind of design principals it means for a fusion device.

  • Fusion rate is self-explanatory.  So far, much of the world has focused solely on this, by driving at triple product.
  • Conduction.  This is all the energy that leaves with the mass.  Metal is the enemy here.  When plasma touches metal - it leaks out.  This robs energy from the machine, killing it’s’ efficiency. Hence you need space around your plasma.  You also want a strong trap to keep the plasma away from the walls.  Lockheed Martin is following a long shot approach to make a near perfect magnetic trap – which if it works – would be a big break through [29 -33].  Foolishly, Lockheed has not published so we do not know where they stand.  I have even seen people build their chamber out of insulators like glass to stop conduction losses [25].
  • Radiation. This is all the energy leaving the plasma as light.  Plasma bleeds energy away, as light.  People have talked about reflecting that light back into the plasma – but that idea is very, very limited.  For example is almost impossible to reflect an X-ray.  Another option is to drive up your density.  That could slow light loss.  Personally, I think your best bet here is trying for a tuned plasma.  In a perfect world you would want a plasma with lots of really cold electrons and a few hot ions.  That would be best.  This kind of distribution may not be possible [29].  It is not clear at this point.  Energy distributions in plasma are a function of many other things: shape, structure, magnetic and electric fields, injection, runtime, ect….  Could you tune your plasma?  IDK.  We need to get hard data proving this one way or the other.

  • Efficiency. This is how well your device spends or collects energy. There has been some exciting work done here. In 1982, a team a Livermore was able to capture 48% of the energy coming off a fusion reactor using something called direct conversion. Basically direct conversion works by putting the charge particles coming off the reactor directly into a wire.

When will fusion happen?  I cannot say for sure.  But I can say that impossible problems have been solved in the past.  150 years ago, human powered flight was considered impossible.  Every expert said it could never be done.  The general public saw it as impossible.  Meanwhile - in the background - a small group of innovators were trying everything they could.  All kinds of wild ideas were tried.  Lots of failures happened.  No one was paying attention.  And then, suddenly, two guys who did not have a formal education and whom no one had ever heard of, created flight.  So impossible problems?  Sometimes they can be solved.

From what I understand the only waste product of nuclear fusion is helium. Given our critical shortage of helium is a worthwhile goal to create a fusion reactor for the purpose of creating helium economically? 

Here are a few issues with that idea.  If you run the deuterium through a fusor, you will lose a lot of mass in the process.  If you fuse the gas slowly, you could probably drive up the efficiency of that process.  You could steal some other ideas from the fusor world – POPS or magnetically insulated fusors – to help out.  Instead of a fusor, you could consider moving to a beam on target, or even beam on beam process.  Making a deuterium target is costly because you would need to cool and compress the gas into either a liquid or solid target – that is not cheap.  The beam-beam approach has instabilities to deal with.

If you got the fuel to fuse, your biggest issue then becomes dealing with the tritium, a byproduct of this process.  One option would be to sell the tritium to someone who would buy it (say a government lab like Savannah River).  You would make far more money on selling the tritium than the helium – tritium is far more lucrative.  Dealing with the tritium in the US is a huge pain.  Where I got my PhD, it took a team of 20 engineers, 4 years and 12 million do deal with our tritium handling system.  There was EPA and NRC permits, air monitoring and recovery.  That is a regulatory/cost nightmare.  On top of the fusion issues, you will have gas compression to deal with.  Either cleaning up the feed or the results of the fusion. I think you should ask a compressed gas expert about this.  I do not know if anyone has done a cost analysis on this business model.  It would all hinge on the differences between the gas prices.

How is it possible for a fusion reactor to control the heat of a fusion reactor without wearing out from the stress?  What accidents are possible?

That depends on which fusion approach wins.  Right now I cannot say what a fusion power plant will ultimately look like.  Most systems keep their plasma spaced out – away from the walls – so if the energy leaks out, it will dissipate in power.  That precaution keeps many machines away from any big meltdowns.  The likely accident would depend on which approach wins.  

·      Tokamak:  If a fusion plant looks like a tokamak with superconducting magnets - then there are known problems.   A superconductor can “become normal”.  This breaks the magnetics and lets the hot plasma lose.  It has happened 17 times in tokamaks [46].  It also happened at CERN and cost them like a year in work. 

·      Laser:  If a laser system wins - there would be little chance of a meltdown.  There is barely any plasma in the laser machine.  An accident there would like be a laser beam firing off and hitting something.  Another accident in the laser system could be a tritium leak.

·       Beams:  If a beam system ends up winning, a plasma leak is also unlikely.  The reason is that beams have almost no plasma in them.

·       Cusp: If the plant ends up looking similar to Lockheed Martin’s approach, then plasma leaking is worth thinking about.  Lockheeds’ approach also has superconductors just like the tokamaks – they could also suddenly lose their super conductivity, “go normal” and break.  That would release hot plasma.

Could fusion power be a workhorse for moving man into space both cleanly and cheaply?

Yes, I think fusion could have a major impact on spaceflight. There are two basic plans for a fusion driven rocket. In plan one, you put a fusing plasma at the apex of a parabola, at the back end of a ship. This material escapes the fusing core at high speeds, bumps against the ship wall and shoots off in one direction. This pushes the ship forward. In the second plan, you have a cavity at the back of the ship. Plasma get sped way up as it passes by a fusing core. The plasma has to shoot through a tiny hole in the back. As it does it flies out very quickly.

There are currently a few NASA funded efforts to look into this:

·      The University of Maryland got some money to look at using a fusor as a space engine. 
·      A company called MSNW has raised about a million dollars to try to do this with a field reversed configuration. 

·       A company called Princeton Satellite Systems has a 500K grant with Sam Cohen a Princeton professor who has built a rotamak.  Sam has the world record for the longest stable FRC ever created (300 milliseconds).  They predict 100 kilometers per second of thrust.  This could get you to Mars in a matter of weeks. 


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