We have become accustomed to expecting only incremental changes in much of our life. The new iPhone excites people with some new feature, but we don’t expect world-shattering technology. That expectation comes despite the fact that the last millennium is littered with such examples.
Our societal changes through the plow, the printing press, and the steam engine seem monumental in hindsight, but few saw them coming — even more rejected the transformative effect they were going to have.
This is, in part, due to a bias towards recent events; we don’t expect things to change drastically in the future even if history says otherwise. Fusion power has been a casualty of this bias, and it is this article’s intention to break any views people have regarding fusion energy, and bring an open mind to the topic. We will start by working to understanding the incredible breakthroughs at MIT’s nuclear fusion center. Armed with that knowledge, I will share an incredibly interesting interview with someone at the heart of that breakthrough. If you make it through, I know you will be enraptured by the promises of fusion and excited about the opportunities that are approaching for this green, sustainable and limitless energy source.
A New Approach to Fusion Research
To many people, fusion research is a page out of science fiction. The promises made by a successful commercial fusion reactor are near-mythical;
Abundant cheap electricity
A near-zero carbon footprint
A very small amount of lightly radioactive material with effectively no proliferation risk
An inexhaustible fuel source.
It is hard not to be attracted to the idea, and it is even harder to believe that we will crack fusion in the same way we have traditional fission reactors. After the first decades of progress, fusion research slowed as its complexity grew. Despite the hurdles, a new entrepreneurial approach is helping fusion to ebb closer to reality.
Why Is Fusion Taking So Long and What Can Be Done About It?
Dennis Whyte, the professor leading the new effort at MIT’s Plasma Science and Fusion center, asks an important set of questions;
Why Is fusion taking so long, while fission went rapidly from scientific discovery to production? And;
How can France produce over three-quarters of its power from nuclear fission utilising a half-century old reactor design, while fusion has failed to put a single joule onto the grid?
The problem comes down to size. When you look at the construction times, costs and scale involved, everything for fission was smaller. Our first nuclear fission reactor was $600 million in today’s dollars and took just over three years to build. ITER, the current focus of much of the fusion community and the first net energy positive reactor, will cost more than thirty times the amount that the first fission reactor did. It will also take ten times as long to build.
The cost and size of ITER require international funding, international cooperation, and the timescale of decades. Consequently, progress is painfully slow and up to the minute technology cannot be incorporated into the design. ITER’s long timeline means that the technology was locked in place more than a decade ago, while full operation will not start for another decade.
Tackling the problem from a different perspective is key to unlocking a technology plagued by the inefficiencies built into multinational projects. Professor Whyte is taking a page from Silicon Valley and adopting a new approach that focuses on developing commercial fusion power. His approach is best described as entrepreneurial research.
By borrowing ideas from the startup world such as failing fast, rapid iteration, and starting with the end in mind, the team at MIT has been able to make some truly groundbreaking changes. Using this new approach, the team’s focus on keeping cost, size, and iteration time under control, has led the team to propose a new style of reactor that solves many of the problems associated with the typical fusion path.
Stronger Magnets Are The Key
Large, complex facilities that take decades to build leave little room for maneuverability. This is the case with ITER and a progression of larger and larger reactors. As our understanding of how fusion reactors has developed, each project has increased in size and complexity. Conversely, if we want to accelerate the timeline, the size of reactors must be minimized, the cost needs to be economic, and the schedule must be shorter. Stronger magnets are the key to all of those goals.
The relationship between the size of a reactor and the magnetic field is exponential. If you can double the magnetic field strength in a fusion reactor, you can reduce the size of an equivalent reactor by a factor of sixteen. To be sure, certain constraints won’t allow a reactor to shrink past a threshold, but a reactor the size of a small house unlocks iterative construction times on the period of years rather than decades. If we could produce magnetic fields twice as powerful as ITER intends to us, then the project would be many times smaller.
Fortunately for fusion proponents, the team at MIT has been able to do just that. By utilizing a new technology called REBCO superconducting tape, the team has opened up a new fusion design that gives a real pathway to economic fusion.
A Breakthrough In Superconducting Magnets
REBCO, short for rare-earth barium copper oxide, is a material that produces magnetic fields nearly double that of its predecessors. The size reduction afforded by these magnets allows for an enormous reduction in costs and development times. Smaller size allows for modularity of parts, which in turns makes repairs and alterations a routine task rather than a monumental undertaking.
Stronger magnetic fields aren’t the only benefit afforded by REBCO tape. REBCO tape also:
Is commercially produced, and products are improving in quality, performance and price.
It maintains its superconducting properties at a far more reasonable temperature of 25 degrees’ kelvin, as opposed to ITER’s 4 degrees kelvin. This cuts costs, complexity, and construction time.
Finally, they are easier to manufacture and handle for construction
This new superconducting tape has changed the fusion landscape, and there is little reason to doubt Professor Whyte’s claims. MIT invented the last generation of superconducting magnet technology and is one of the world’s best in the sector. Using these magnets, MIT hopes to substantially cut costs through decreased size, modular construction, and a focus on unique technologies.
Modular, Replaceable, Upgradeable
Exactly how much of a cost reduction are we talking about? The estimates for material costs for a grid-scale reactor producing 250 MW of power sits at roughly $360 million. By basing the cost estimate on previous fusion reactors, the assembled cost would be $5 billion, still a far cry from dropping the price tag under $1 billion — but we’re getting there.
So how will the rest of the gap be bridged? Smart design, and clever construction.
A typical engineering project will have materials costs ranging from 75% for a very simple project, down to the low single digits for a very complex or unique project. Fusion reactors are made from extremely expensive materials, so some of the complexity in design and construction are smoothed out by the high cost of materials. Even with that in mind, the materials cost sit at only 7%. In effect, fusion reactors of the past have been very inefficient at arranging materials into the final shape.
Not one for easy goals, Dennis’ team is aiming to get this material portion of costs to 50%; a 700% improvement on the current design and construction costs. If successful, this would unlock a full-scale reactor costing approximately $750 million. Making such a mammoth improvement seems complicated, and it is, but there are examples of this happening throughout history, and there is one that is going on as we speak at a company called SpaceX.
“I was trying to understand why rockets were so expensive. Obviously the lowest cost you can make anything for is the spot value of the material constituents. And that’s if you had a magic wand and could rearrange the atoms. So there’s just a question of how efficient you can be about getting the atoms from raw material state to rocket shape.” Elon Musk
Elon Musk aimed to reduce the cost of space travel by attacking build efficiency. Using that approach SpaceX has already cut costs of sending something to low-earth-orbit from well over $10,000/kg several years ago to roughly $2,700/kg today, and is expecting to cut transport costs to $1,700/kg by 2018. That is a factor of five improvement in price in less than ten years. Furthermore, SpaceX’s journey was possibly a more difficult one. With rockets, there was a much larger economy of scale and a deeper history of design before SpaceX entered the rocket-launching industry. With fusion energy, the only assemblies have been scientific prototypes. It is not hard to imagine fusion making a quicker and faster reduction in costs taking a similar approach.
If the team at MIT is successful, an electricity producing reactor could be built at the national scale instead of the international level. It could even be privately funded through a consortium of investors. This is the importance of the ARC fusion reactor; short for Affordable, Robust, Compact Reactor.
At one-quarter the diameter of ITER, it can still produce the same amount of power and, assuming Professor Whyte achieves his goal, it would cost hundreds of millions rather than tens of billions. However, research dollars are needed to get there, time is required, and a continuous flow of talented engineers and scientists.
In the hope of sparking a revolution for fusion research, the team is hoping to build the stepping stone for ARC. That project is the aptly named SPARC reactor, short for Soonest-Privately funded- Affordable, Robust, Compact reactor.
For Dennis’ team, SPARC is an answer to the forces that frustrate progress in fusion. Rather than building a full-scale reactor, they are making the most minimal product that proves the idea. It is the prototype that will be used to demonstrate the breakthroughs that this new technology allows for, and acts as a stepping stone to a power producing reactor. It is important the costs and the technology are enticing enough to be privately funded, and SPARC will aim for expenses in the hundreds of millions. If successful, there is little doubt that the money required to produce a full-scale ARC reactor will be available, and that the world will be changed with it.
The intent of SPARC is to prove that these new magnets and a small reactor design can indeed ignite fusion to the point that it can self-heat. Self-heating means that a fusion reaction no longer requires external energy to remain hot enough to create fusion reactions; instead it is heating itself with its own reactions. At that point, the science will no longer be a risk, and it truly becomes an engineering challenge. At that point, fusion energy becomes a reality.
If SPARC is successful in bottling the power of the sun, igniting fusion on earth, and controlling the reaction, the larger ARC will be ready and waiting around the corner. At this point, there is little to doubt in the science of SPARC and many people will be waiting with more than a little interest for the first signs of a successful reaction.
Interview with Professor Whyte
While this article hopefully brings about an interest in fusion for some readers, I know that this interview will give readers an incredible sense that we are getting close to breaking open fusion energy. It is worth reading and understanding, and I know a that I for one will be on the lookout for ways to be involved going forward.
What is the largest scientific challenge with SPARC?
Professor Whyte — SPARC is intentionally designed not to have any — which is always tempting mother nature to throw you a curveball. But, the best answer to that question is, what happens when the plasma starts to heat itself to a significant level. This is the whole point of SPARC; it is designed to test a regime of fusion we have never accessed and have never assessed.
Everyone can understand that when a medium starts to heat itself, the level of external control of a system starts to decrease. A bonfire is different from a blowtorch against a wet log. We are moving not necessarily to a bonfire, but less external control. This isn’t a risk in some sense; it’s what we need to explore.
When a blowtorch is heating a wet log, the log is getting warmer, but the second you turn the blowtorch off the heating stops since it won’t ignite. This is analogous to our current fusion research. SPARC would ignite the log and start a bonfire, and at that point, it is harder to control.
Getting back to your question, it depends on what you mean by risk. There is a risk in SPARC that once you start turning on large fractions of self-heating the plasma could become bound and determined to take itself to a place of instability. That is the fundamental questions and exactly what we are here to assess. Any energy production system has to have that to work.
In the end, we are answering the fundamental question about fusion economics. We are all convinced that we can make a system that makes more energy than it consumes and is self-sustaining. The key economic question is; how much power you can make per unit size, that’s the economic output per dollar invested. It needs to be answered in a thorough way.
You have spoken about reducing costs substantially through better design. We have already seen SpaceX succeed in a similarly complex industry. My gut feeling is that this would be easier to do for a fusion reactor since there isn’t such a large fixed cost in the fuel that can’t be avoided. What is your view on that?
Professor Whyte — To be clear, we’re not talking about the entire plant but the core heat engine of the plant. The irreducible costs are the material costs — the superconducting tape, the steel for the vessel, and the molten salt that is used for the blanket.
The blanket in a fusion reactor is used to shield the vessel and external magnets from the high energy neutrons that are created from the reaction. This isn’t a problem, but is the intent of a fusion reactor. Slowing the neutrons from a serious fraction of the speed of light to a rest creates a tremendous amount of heat. In the molten salt blanket in ARC, the liquid would flow around the reactor to remove neutrons and heat, and to generate electricity through a heat exchanger and then a typical steam reactor.
Materials costs come out to roughly $350 million, and if you only compare that to the mass of the device, this is going to be a lot less expensive than ITER. You have said this right, and we have had an independent firm come and look at this, and fusion seems to be a technology that is very amenable to reducing the cost per watt by two things.
First, once you start making more of them, rather than one off designs, it starts to become cheaper as the upfront investment in tooling and design is completed. This is why with ARC, everything is designed to be modular. Once you have built the reactor once the cost per unit starts to come down.
Second, we need to come up with better and more standard assembly techniques. Our independent assessment with a team from outside MIT observed that if you can get assembly costs to raw material costs that are more like modern automobiles (about 50%), which are similarly heterogeneous complex assemblies, this reduces the cost substantially. This is exactly what Ford figured out through the assembly line and modularity. We think there is absolutely pathways to doing that, and the good news is you are starting at a point that the cost per watt using the pessimistic scenario is still putting costs identical to those of the first fission power plants. And, we all know that fission reactors took off shortly after that.
Can You Explain How You Are Bringing The Cost Multiplier Down?
Professor Whyte — The first one we have looked at is increasing the power output of ARC. ARC was intentionally designed to mimic ITER’s fusion power for comparison purposes, because ITER’s 500 MW fusion power goal is an exciting goal. But, that was not really a physics point, and what we have been doing in the design is to understand where are the limits in the heating. And it is the heat exhaust that is the limiting factor (how quickly can you remove the heat). There are clearly ways in ARC to make more fusion power, and we limited it where it was.
On the other side, the highest cost in ARC is the magnetic coils. What we have been starting to work on is realistic research and development on building coils. What is it going to really cost, and how modular can they be? It no longer becomes an academic paper anymore, and you don’t have to build a reactor to start finding about those things, you just start making coils.
The third one is the capacity to make this superconducting tape. And, we are not in direct control of that, but I think that by showing this mission towards fusion would produce an extraordinarily large market for those tapes, the market will take care of itself. That starts driving the costs down. There are now 4–5 serious companies that are starting to make this, and their capacity now is at the point that together, they could create SPARC. There are many modifications that you can make to the production of the tape to optimize it. Ultimately there is competition in the market and it seems poised to start to ramp up — but we’re not there yet.
In the renewable space, the raw production of a renewable joule of electricity doesn’t account for the externalized cost to the grid. In Germany, billions have been spent trying to maintain such a grid. We see the same thing with externalized costs in fossil fuels with pollution. Can you talk about this in regard to fusion?
Professor Whyte — It is a key point to make about fusion, that you don’t need to invent a new grid and industry to be able to utilize it at large scale. You can just build a plant, and from the outside you wouldn’t be able to tell whether it is a gas, coal, fusion, or fission plant. That is what makes fusion so enticing. A few weeks ago we had some environmental groups in for a discussion. And we realized that when people think about fusion, they believe it is going to an incredibly exotic method of putting it on the grid, and it’s not. It produces no carbon, and it is free of the concerns we have about fission, and you could go to a coal power-plant and swap out the coal furnace for a fusion reactor and produce energy.
It is an important point to make, and the renewables are the technology that need the exotic grid. It is difficult to adapt wind and solar at a large scale.
With any long term project such as ITER, it is inevitable that breakthroughs occur after the design has been locked in to place. This seems to be the case with ITER and this new superconducting wire. What are your thoughts on the idea that it is inevitable that the next generation passes the capabilities of the first generation before it can even be built for multi-decade projects?
Professor Whyte — Yes, I think it is. It wasn’t guaranteed with ITER, and the design was made in the late 1990’s. The basic aspect of the superconductors in ITER became fixed, water cooled steel shield blankets, no significant tritium breeding, unbreakable magnetic field coils, those were the big decisions to make. I know people that were part of the design, and the design had to be frozen in.
Now, people knew about these high temperature superconductors in a theoretical sense — in a laboratory. But there was no obvious way that these were going to get to actual commercial tapes in the next 15 years; there was hope that that would happen, but no guarantee. It is a difficult decision to manage.
The problem with ITER is not its design, it was a cutting edge design at that point. We ourselves at MIT were right in the middle of that, when we figured out how to make Niobium superconductors at the scale of ITER, that was an incredible advancement at the time. The problem is that its twenty years later and the project is still ten years away from being fully assembled, and full fusion out to 2032. That is over 30 years past when those decisions are made. You couldn’t design this iPhone in the 1990’s, the technology didn’t exist.
I’ll make it clear that we have no desire to shut down the ITER project. Because it is so large to answer the fundamental question about self-heating, everyone around the world recognized that we needed to get fusion to the point that it could self-heat. If you can’t answer that question about making net energy and electricity, you can’t succeed. The strategic problem came with having all of that rely on a single project. Never in the history of magnetic fusion, or any type of fusion, have we ever relied on a single project.
There is a reason for that. They all attack the problem in different ways and find a way to succeed. That means you learn things. Our motto would be, keep supporting ITER. But here is another design that brings different kinds of risks, but is an appropriate distribution in the plan to get to self-heating.
What I find interesting about your approach to fusion is that you are integrating a startup mentality. Can you talk about how that change of mindset came about and how this could be applied to other large research projects?
Professor Whyte — It hasn’t been me personally. I have to give credit to Bob Mumgard in our group. A lot of the things that him and his team looked at were part of this. In many ways, us in fusion are the ones that are way behind.
What is really interesting, is that many astronomers get their time through telescopes that were not sponsored by the government. They were sponsored by large private organizations. And, now the energy part is catching up, and not just solar and wind startups. But, big scale fusion and fission startups are adapting this model as well. It is quite surprising in some ways. If you had asked 20 years ago whether startup companies would be dominating the conversation about rocket technology, fission energy, fusion — people would have looked at you like you were crazy. However, it is starting to progress towards that.
You can even see this with President Obama’s recent speech regarding the public-private partnership that would bring people to Mars. Clearly making fusion and fission happen from the private industry has a different scale than telescopes, or battery technology, but I think we will see a mix of these different models. It is exciting to be at the forefront of establishing what those models will look like. I think that in advanced nuclear energy, it cannot be totally private, there has to be a public partnership. Public support needs to come from the regulatory aspects and support for R&D. The lift that it takes to get these things going is huge. At MIT we have different ways that can help us succeed, not from private funding alone, but from public sources, that allow us to succeed in a way that a private company cannot.
I don’t know what the answer will look like in the end, but we are going to go through a great experiment about what that looks like.
In project management we see issues arise from engineers getting too tied to one design and less willing to iterate. Do you find that because you have these PHD students and design teams rotating on a relatively constant basis, that you breakdown a lot of those barriers to change and innovation quite easily?
Professor Whyte — Yes, it is exactly why you enlist students, and why startups have a lot of young people running around them. One of the people working on my project now worked at SpaceX over the summer, and he was saying everyone looks like they are 30 years old. They have high-school interns writing code that will run their rocket, it’s incredible. But, you also have to channel this in a proper way.
This is exactly what we do with our design classes. You unleash creativity because the young people don’t have the burden of having all of that memory on how things are done before; which is good, but it needs to be tempered with some experience. Our approach is to say, that is a really interesting idea, but let’s go forward with it and see if it is going to hit a dead end. You think through it, and you find that for every great idea in one of these papers, there is at least four left to the side somewhere.
I think you touched on exactly the point. You don’t have the same people looking at the problem for twenty years. You cycle through a new set of people challenging the status quo, but doing due diligence on the work. That is the two edged sword of innovation; A lot of people come up with great ideas, but they don’t have the technical know-how to evaluate them. That is what we’re teaching in this class. We try to strike that balance.
A concrete example I can remember. A student came up with an idea, and I initially dismissed it but I challenged them to prove me wrong. In the end, they came back with the solutions and convinced me that was the way to go. It is one of the best parts of my job.
Fusion is obviously mired with skepticism. It seems like we are approaching a tipping point where many more people are becoming interested and believers in a way — one great sign of this are private companies raising money in fusion. Are you seeing a big pickup in interest from people outside of the typical fusion community?
Professor Whyte — Yes, a lot.
One of my colleagues on the fission side said, you have to realize that nuclear energy is opaque to almost everyone in the population. It sounds like science fiction to most people. But, through careful messaging and engagement with people we can change that. It is amazing how isolated the fusion community became after the agreement to build ITER. Since the timescale for the last big fusion reactor was 20 years ago, you start losing touch with your customer. And who is your customer? The person that is going to pay for the research to get done to generate fusion electricity.
With fusion it is a very exciting time. Even 4–5 years ago, fusion and nuclear energy in general were being dismissed. Society moved toward the idea of needing clean energy now, and took off with renewables. Now, we are seeing a big epiphany that, while renewable energy are great energy sources, they cannot get us all the way there. So now they are looking around for a solution, and fusion gives that solution. Across the industry there is a growing realization of that, and there is a lot of momentum building.
The scientific community is starting to really say, we need to get behind fusion as a way to get toward a carbon-free energy society. With renewables we just don’t have a way of getting there.
I know that I’m personally interested in getting involved, and I imagine that others would be as well. Is there a way at the moment to do that?
Professor Whyte — It is interesting that you said that, one point that we have started to discuss internally is about how to open a community. Fusion is multi-disciplinary in its design challenges, and I have an email here from an architect who saw one of my talks. He pointed out that getting this reactor together is like an architecture problem — similar to the crane that exists within a structure during construction of a skyscraper.
He pointed out that he doesn’t know anything about fusion, but he would love to help come up with some ideas with how to put this together. He put together some fantastic renderings about how this system goes together. Now, this is a small piece, but we want to explore how to build a community that is, in some sense, an open design community. Hopefully we can bring a group of people with different skillsets together and take on different challenges of the design with ARC and SPARC. This would be a fantastic way to bring in more people and more ideas in an effective way.
This post was originally published on Medium on Nov 22, 2016: A Breakthrough in Fusion Puts Us On the Pathway to Unlimited Energy.