A Timeline for FUSION energy

A FUSION ENERGY BREAKTHROUGH

THE NEW FUSION QUESTION

The subject of this post is an inspiring update call I had recently with the Head of Tokamak Operations at Commonwealth Fusion Systems, Alex Creely, but before we get to Alex, a little background:

I get giddy about fusion as an energy source. The promise – unlimited, carbon-free, inherently safe, baseload electricity forever – is immense. My visit to ITER, the world’s first full-scale experimental nuclear fusion power plant under construction in the south of France was one of the highlights of my life.

I’m not ashamed to say that I cried real tears. The majesty! The Brobdingnagian scale of the thing! But most of all, the JOY of being surrounded by scientists from the EU, the US, Russia, China, South Korea, India and Japan – all working as a team on behalf of human kind! So yes, giddy. Guilty, your honor!

But here’s the thing: the science is solid. The engineering is coming along faster than you think. And there is no question in my mind that it will work.

I’ll say that again: It’s coming. It will work. For most people who have absorbed the popular cynicism born of many decades of over-promise and under-delivery, such a definitive view will perhaps be a little confronting. Perhaps you felt a slight twinge as your hyperbole detector kicked in?

But it’s the position I’ve happily defended, on the basis of first-hand insights from physicists and fusion research, since 2015.

To me, the critical question is no longer, will it work? but rather, Can we make a power station that produces commercially-competitive electricity?

And secondarily, assuming the answer to the above is ‘yes,’ When could fusion make a significant impact on the global energy system?

ENTER COMMONWEALTH FUSION SYSTEMS

I first encountered Dennis Whyte and Zach Hartwig and the concept behind what would become Commonwealth Fusion Systems (CFS) at a briefing in Cambridge, Massachusetts In 2017. Dennis Whyte is a legend in the fusion community. Zach Hartwig is a brilliant and passionate MIT physicist. I think there were other scientists present, but to my lasting embarrassment I cannot recall their names.

The big concept they shared was this: the latest high-temperature superconducting materials make it possible to design a vastly more cost-efficient fusion power plant.

Stepping out their logic:

1. The most practical machine for achieving sustained fusion reactions is a Tokamak. The Tokamak works by squeezing (confining) atoms closely using stupidly powerful electromagnets (think of a donut-shaped particle-collider smashing hydrogen isotypes together to make helium plus neutrons plus energy, the energy boils water, makes steam, turns turbines which make electricity and voila! Power!)

2. Stupidly powerful electromagnets are made from high-temperature superconductor (HTS) materials which, when lowered to a certain temperature, allow prodigious quantities of electricity to pass through with ZERO electrical resistance (somewhat confusingly, “high-temperature” is a relative term and means you don’t have to refrigerate quite so much :-)

3. Newer HTC materials are stronger and better and allow you to build those stupidly-powerful electromagnets MUCH SMALLER, which means you can build Tokamaks smaller, which means smaller construction costs AND greater output efficiencies. ie more commercially-competitive electricity.

To reinforce the point, they handed out sample-snips of the latest HTS wire as a learning aid. I still have mine, and I still bring it on-stage when telling the CFS story.

Since then, I’ve followed their progress closely and visited whenever possible. Zach Hartwig in particular has displayed, over multiple years and multiple meetings over a sandwich, infinite patience and good-humour by answering all my naïve and somewhat over-exuberant questions.

His insights prompted me to explore related science elsewhere, such as my aforementioned visit to ITER in France and a visit with Paul Chu at the Texas Center for Superconductivity. I’ve learned more about the human side of the fusion innovation scene as well, especially Dennis Whyte’s inspired leadership and dog-with-a-bone perseverance that you could not guess lies behind the mild-mannered exterior I encountered.

The story of Dennis’ journey, his personal leadership and his interactions with the greater ecosystem of students and scientists in the fusion community is very great. I’m tempted to try and tell it here, but it’s already been told far, far better by Rivka Galchen in the New Yorker in what is unequivocally the best article on the recent fusion story I’ve ever read. If you want to dive deeper, make Rivka’s article the very next thing you read.

PLASMA WRANGLER

Zach Hartwig is now concentrating on his work at the MIT Plasma Science and Fusion Center, and Dennis Whyte was unavailable when I was visiting Cambridge recently, so CFS kindly made a new introduction and set up a call with Alex Creely, Head of Tokamak Operations for CFS.

Alex was employee number 13 at CFS. Remarkably, he was one of Dennis Whyte’s students and participated in the problem-solving and idea-building process that led to the design of the Tokamak he is now responsible for building. From now on I’m calling him Chief Plasma Wrangler. Happily, he also displays the same generosity, patience and good humour as Zach in answering my many questions.

STATUS AS AT YEAR-END 2022

First, Alex gave me an overall status update, the highlights of which are:

• On September 5, 2021 CFS hit a key milestone, and proved out the magnetic side of their power plant design, by running up a toroidal field magnet to a staggering 20 Tesla, making it most powerful magnetic field ever created on Earth.

• CFS completed Series-B funding for a total of $1.8 Billion – enough to fully-fund construction, commissioning, and operation of SPARC, their reduced-scale prototype reactor to test out all design concepts and prove all the various systems work in operation.

• CFS has started building SPARC

• CFS has started early design work on ARC, the full-scale prototype which will run for longer periods and be used as the basis for commercial power-plants.

• CFS has hired 409 employees (and growing) from aerospace, fission, automotive and many other industries in what is a truly multidisciplinary approach.

• CFS has opened a facility at Devens, Massachusetts with all space necessary to house personnel, manufacturing and operations.

Things are moving along, aren’t they?

I asked him if there was any ingredient he was missing, any resource he was still seeking to get the job done, and he told me that, other than always looking for collaboration opportunities, he has everything he needs. Powerful statement, that.

CONTINUOUS POWER, TOKAMAK-STYLE

I asked Alex about two challenges I’ve been thinking about with respect to generating commercially-competitive electricity. The first was how to achieve more continuous Tokamak operations. Continuous Tokamak operations are hard because you’ve got keep a hundred-million degree plasma turning and burning within its magnetic ‘bottle’ – don’t let it wobble too close to those tiles!! – while at the same time injecting minute quantities of fresh ‘fuel’ and exhausting Helium ‘ash.’ Oh, and it all needs to happen in a vacuum.

Tokamak operations are thus stop-start affairs: fire one plasma ‘pulse,’ then do a reset, fire another and reset, and so on. So, how to generate continuous electricity from what is essentially a ‘discontinuous’ process? Do we need, for example, multiple Tokamaks running side by side with overlapping cycles …

Well, no actually.

As Alex explained, there is no need run a Tokamak continuously because the surrounding blanket of molten salt has significant thermal mass which means it can store a LOT of heat; the heat can be drawn off continuously to boil water, make steam, turn turbines, while periodically being ‘topped up’ by the next fusion pulse.

SPARC operations, for example, are expected to look something like this: 10 seconds to power up / 10 seconds making full power / 10 seconds power down / followed by a gap of perhaps 20 minutes or possibly an hour if it works really well, for the generated heat to dissipate. Cue the next cycle, etcetera. ARC operations will pulse for longer, perhaps for tens of minutes at a time, but will essentially follow the same pattern.

Turns out I’ve been mulling over a problem that isn’t really a problem! That munching sound you can hear is me - eating humble pie.

MODULAR MAINTENANCE

The second challenge I asked about was maintenance and downtime. Every power plant needs routine maintenance. Coal, gas, wind, hydro, nukes, even your trusty solar panels need an occasional check and wipe-over. The longer the downtime, the worse the economics.

For fusion, a key factor will be how often and for how long we need to stop operations to inspect and refurbish the tiles lining the Tokamaks. These tiles will be subject to tremendous abuse. They are necessarily made from special materials. They are expensive.

As I learned on my visit to ITER, the materials choices and optimal longevity outcomes for these tiles rate as one of the biggest learning goals we have. And its not just tiles: when you are powering up the strongest electro-magnets ever made, to create and harness what is essentially a PIECE OF STAR in a machine, one imagines more than a few components in that machine will need regular maintenance!

This time, my question was more on the mark.

But then Alex had another surprise up his sleeve (I think he was enjoying himself at this stage). CFS doesn’t intend to refurbish in situ. Because their Tokamak design will be so darned small, when maintenance falls due, they intend to crane out the vacuum vessel in its entirety and crane in another!

The direct parts/materials costs, of course, will be unchanged, but this means they can employ a dedicated refurbishment facility to make access easier, and CFS can ensure that the disruption to generation operations, at least, is kept to an absolute minimum. A wonderful example of lateral thinking.

CAN FUSION PRODUCE COMMERCIALLY-COMPETITIVE ELECTRICITY?

The short answer is, we don’t know yet, because that’s what SPARC is designed to find out. Until all the refinements and complex systems are put together in real-world long-duration testing, no one knows. Too many variables, too many interdependencies.

We won’t know the heat output until we know the ideal plasma duration. We won’t know the optimal composition of the tiles – the one that gives the best long-term durability for the dollar – until we put some real miles on one of these babies. The molten salt I mentioned is nasty corrosive stuff, not at all easy on plumbing, which brings its own challenges.

There are external factors. The price of carbon will be more widely accepted. The price of fossil fuels will likely be much higher. And while fusion engineers are busily improving their efficiencies, other engineers will be doing the same in photovoltaics and wind-turbines and energy storage and grid-interconnectivity and long-distance electricity transmission (no one is stopping work on any of these!) all of which might combine to change the projected demand for baseload.

And like the first nukes, solar PVs, wind-turbines and other power generators, the first fusion power stations will start clunky and get better as we learn. The good news is, we’ll have our first data from fusion experiments in only 2-3 years. And I, for one, will be following closely!

THE CFS FUSION ENERGY TIMELINE

We talked timeframes. In a nutshell, CFS hopes to achieve this:

• First plasma in SPARC in 2025

• Net energy out of SPARC by year-end 2025.

• ARC up and operating for long, continuous periods – early 2030s

And somewhere in our discussion, I wrote down the delightful aspirational statement “Ten-thousand ARCS by 2050,” which gives an idea of how the good folks at CFS are thinking about the amount of energy rollout: get the design right, distribute it, let a thousand (or ten-thousand) flowers bloom.

Achievable? I think so. Admittedly, without working inside CFS, much of my optimism comes from the decidedly subjective method of looking in the eyes of scientists like Alex and listening to their frank optimism – they believe, so I believe – but I’ve been watching and learning for many years now, and if we’re looking for another data point, ITER, with its considerably larger machine is aiming for first plasma in 2025 and continuous operations by 2035, so overall I would say: produce more energy through fusion, more than achievable.

Add another 10+ years for learning and refinement and production, and this sets the mid-2040’s as the earliest we can hope for a significant impact on the global energy system (ie via many newly-commissioned power plants). In the context of the climate emergency, that doesn’t relieve us of the vast transformations we must make NOW to get off fossil fuels and ramp renewables and clean energy sources as fast and aggressively as we possibly can.

The urgency is too great, the looming consequences in human suffering are too severe to consider any other strategy and call it sane, BUT make no mistake, switching on supplies of clean, green, unlimited-fuel baseload electricity in the 2040s or 2050s or 2060s would still be more than good, it would be mind-blowingly fabulous.

It would change the way we think about energy in every industry in every economy. It would go a long way toward 100% neutralizing energy geopolitics. It would make for a vastly more equitable future.

And on achievability, I will also say this …

• The fusion community is populated by remarkable, energetic, committed people who are doing their utmost to save our planet from the worst perils of climate change.

• I’m impressed by the parallel work streams. At CFS, tile designs are being made and tested, magnets are being run up, a small-scale reactor is being built, regulations are being hammered out, and early design work is underway on the full-scale reactor – all in parallel.

• This is also true of the fusion community more broadly, facilitated by shared values and motivation and a remarkable culture of openness. CFS, for example, shared all the physics for their SPARC design via open access journals a couple of years ago. It seems to be the way of this community. A rising tide lifts all boats!

• It’s fun watching hitherto ambivalent investors sniffing the winds and detecting … opportunity! More milestones and hard data will spur exponentially greater interest, and I expect a small army of new supporters and investors will materialize and ‘pile on,’ just as happened to a couple of other maverick pioneers named Wilbur and Orville after a successful demo or two ...

… All of which means there is every chance the good people at CFS will BEAT their timetable.

UPDATE - 15 February 2024

Alex kindly sent me an update on targeted timelines:

• 2024 and 2025 - SPARC assembly

• Late 2026 - SPARC first plasma

• Early 2027 - SPARC net energy out

• Early 2030s - ARC operations (unchanged)