A portion of this video is brought to you by Surfshark.
“Woah ….
Woah! This is massive!” “Welcome to the JET tokamak”
Getting to see the JET tokamak fusion reactor in person was an eye-opening experience,
but not in the way you might expect. What I got to see during my time at the Culham
Science Center in the UK went well beyond what JET is doing. There’s a whole ecosystem
that’s needed to support a future fusion industry, and the UK government is really
pushing every aspect of that. There’s a lot of buzz around fusion startups,
but for any of this to work, it’s going to take a holistic view to address the many challenges
around it. So what’s that going to take? And … what's it like to stand inside a tokamak?
I’m Matt Ferrell … welcome to Undecided.
The old joke is that fusion energy is always 30 years away, however,
it’s long running experiments like JET that have helped to push our
understanding of fusion forward and make major advances over the past few decades.
Just a couple of years ago it set the record for longest sustained energy.
The whole reason I make these videos is to share my excitement and interest in
technology … in what humanity is capable of when we put our collective minds to a
very difficult problem. I’m not a scientist, so these videos are me sharing my learning journey
and curiosity. And my journey over to the UK, which I’ve dubbed as my “UK nuclear tour,”
is a part of that. This is the first in a series of videos that I’m releasing about
that tour. You’ll get to see everything from large government-funded research facilities,
to privately funded fusion, to a small startup doing something with fusion that
you might not expect. So be sure to subscribe and turn on notifications to not miss those.
To kick things off in this video, I thought it would be good to look at
the big picture when it comes to fusion. And there’s no better place to start than
the UK Atomic Energy Authority (UKAEA) and the Culham Science Center in Oxford. This
really is a braintrust of brilliant people trying to tackle not just fusion energy,
but everything that will be needed to support it. I’ll be getting to the JET and
the MAST-U tokamaks in a bit, but there’s some interesting challenges that come with fusion.
Just for a quick refresher, when you’re talking about nuclear power plants that we’re all
familiar with, it’s nuclear _fission_, no “u.” That’s when a neutron slams into a larger atom,
which splits it into two smaller atoms. Additional neutrons are also released in
this process and can start a chain reaction by slamming into more atoms to continue the
process. When an atom is split a massive amount of energy is released in the form
of heat. In the nuclear reactors we have today around the world,
that heat is captured to turn water into steam, which then turns a turbine to produce electricity.
Fusion is the opposite of fission, and it’s what’s happening in our sun and all stars
in the universe. Fusion is when two atoms slam together to form a single larger atom,
however, the single larger atom will be ever so slightly lighter than the
two separate atoms. That extra mass is converted into energy. For instance,
like two hydrogen atoms fusing together to form one helium atom. The power released in
this process is several times greater than the power released from fission.
Once the fusion reaction is established in a reactor like a tokamak, a fuel is required to
sustain it . There’s a few different key fuels that are options for fusion: deuterium, tritium,
or helium-3. Both deuterium and tritium are heavy isotopes of hydrogen. If you
look at this graph, you’ll see the output differences between deuterium + helium-3,
deuterium + deuterium, and deuterium + tritium. It’s why most fusion research
is eyeing deuterium + tritium because of the larger potential energy output.
One important thing to keep in mind is that some of these reactions, like deuterium + tritium,
produce neutrons. And neutrons, unlike some other forms of ionizing radiation,
can actually make things they impact radioactive. It’s a process called neutron activation. While
the radiation generated by fusion reactions is short lived, it’s still something you have to
contend with and address … especially with maintaining a tokamak reactor.
That’s where my first stop at the Culham Science Center comes into play and the solution I got
to see. Before we get to that, I’d like to thank Surfshark for sponsoring this portion of today's
video. I always recommend using a VPN when using public Wifi, but VPNs can be very useful even
when you’re home. A lot of online services use some pretty sophisticated commercial tracking
and machine learning to apply very targeted advertising ... a VPN can protect you from some
of that. SurfShark’s CleanWeb does a great job blocking ads, trackers, and malicious websites
making it safer to use the internet even at home. And you can even make it look like your IP address
is coming from a completely different country. This can come in handy if you want to stream
a video that’s only available from a specific location. One of the best parts of SurfShark is
that it’s easy to set up on all your devices, whether that’s iPhone or Android, Mac or PC.
SurfShark is the only VPN to offer one account to use with an unlimited number of devices. Use
my code to get 3 extra months for free. SurfShark offers a 30-day money-back guarantee, so there’s
no risk to try it out for yourself. Link is in the description below. Thanks to Surfshark
and to all of you for supporting the channel. Back to the first stop at the Culham Science Center.
I had a chance to check the Remote Applications in Challenging Environments facility, or RACE,
which is all about creating mechanical systems to maintain dangerous or difficult to access
machinery. One of the systems they’ve created is called MASCOT, which is essentially acting
like an extension of an operator’s arms and hands. They can manipulate the remote gripper
to remove panels, change out components, and do maintenance at a safe distance.
One of my first questions, which some of you are probably wondering too,
was why this isn’t a computer controlled system. Why use a human operator?
“So there are levels of automation in this in terms of complete automation,
given that it's one machine and we are again, very delicate around everything we do. Impacted delays
is so huge. It's still being done manually and well through the life of this machine.
Looking forward to other reactors in the future, there will be higher levels of automation in that,
where they're gonna be running for extended periods of time, have longer
life durations, and be doing more routine work. Where this is an experimental reactor,
it's much more, you might do something just once. So the idea of programming an automated
sequence for it … there isn't that huge value. But definitely going into future reactors is that.”
“So you can retract the robot, pull the booms in and out,
move them into position through automation. But when it comes to the actual handling of
the environment, that's what a human takes over.”
As you can see from the monitors, they’ve created a digital twin of the reactor to
work within for simulation, and to also give them multiple viewing angles of
what’s happening in the environment. Before an operator can even touch the real machine,
it requires 1,000 hours of training time, which I actually got to experience
for a few minutes. To say it was fun would be an understatement.
“This is, yeah, photo switch for the switch. And push
this button. The good button is on that is force speed start
to activate. Okay. You can so hit the table. You can feel the force speed back. Yeah.”
“Okay. And. Oh, whoa. That is crazy.”
“Oh, another bingo.”
“Yeah…”
“Okay. This is the best video game I've ever made. That is so cool."
“Can we fight you on that?” “ Yes. That is so awesome.”
You could feel the edges of the block, or the right hand gripper knocking into the left hand
gripper, as well as the weight of the block when you lifted it up off the table. It was
pretty easy to see why those haptics are important for operation. Down on the floor of the facility
they have a massive work area of experiments with different technologies at play. Not to go down
a rabbit hole too much, but in talking with the team they explained why they’re experimenting with
mechanically driven robotics, with things like gears and motors, versus cables like MASCOT uses.
“These are off-the-shelf, two-handed manipulator robots that we are starting to work with and see
what the value is in applying that kind of off the shelf technology.”
“Very different in the technology they use between them. This one is
all mechanically driven throughout with conceptual shafts and gears
as opposed to a cable driven system like the mascot or the other, off the shelf robot there.
They have different benefits and drawbacks. The cable driven ones are much more dextrous and feel
a lot lighter, but the mechanically driven ones are massively more radiation tolerant.”
When I got to try out this setup, it felt somewhat similar to the training system I used,
but I could feel the ticking and grinding of the gears as well. It took a minute to get used to,
but … I don’t mean to brag, but I think I picked it up pretty quickly. It’s
surprising how quickly you adapt to the machine and get the basic
hang of it. My lifetime of playing video games may have also helped.
But even with that training, you still need something to test it on
in the real world before you move into use on the actual tokamak,
which is why they have a lifesize replica for the team to train on. I felt like a kid on
Christmas morning getting to go inside the tokamak and get a better sense for
the size and scope of the device. In case you didn’t know, JET is shaped like a giant donut,
which shouldn’t be too much of a surprise since a hint is right in the name: Joint European Torus.
“So this is the inside of that torus. So this is where we come to do training and we practice using
mascot, which is our remote manipulator that we do work with. Essentially like a one-to-one
replica of the inside of our machines. So it's all sort of made from scratch … apart from this
section that I'm in right now, this is one of the actual octas of a jet. So Jet is split into
eight segments, but there's actually nine, so the spare makes up part of the training facility.”
“So mascot snakes in round here. And then we have the task module come from a separate
opening. The task module is a table, but a fancy table. And, the operators can basically practice
all of the tasks that they need to do actually in the machine because it's really important
that the machine is turned back on as quickly as possible. So, it is really important that the
operators know what they're doing and they're really skilled at what they're doing because
dropping a bolt somewhere and here would be bad. But dropping a bolt inside JET would be really bad
While maintaining Fusion reactors is a key part of RACE’s research,
it’s not the only application of what they’re doing. It has much broader applications for
other industries that have hazardous materials or environments that might
be difficult for humans to safely operate in. We’re looking into a potential future
video on this topic, so let me know if you’d like to see more on robotics.
I’ve just scratched the surface of what I saw at RACE, but I was blown away by all of the different
experiments. This is an aspect of fusion energy that I hadn’t thought about or even considered.
My next stop was the newer MAST-U tokamak, where I got to speak to the Director of Toakamak Science,
Dr. Fulvio Militello. This ties right back to what I said at the beginning.
The joke that fusion is always 30 years away is ignoring all of the incredible
progress that’s been made over the past 40-50 years. Fulvio showed me the first
working tokamak that was operated at the facility … it was oddly cute.
“Our tours start here because this is a tokamak reactor, this is an experiment that we had here
on site working. It's not a model, it's the real thing. In the 1960s. And this also,
to give you an idea of how much the field has evolved in 40, 50 years, it's an incredible
progress. From a device that can literally sit on a table to what you’ll probably see at JET later.”
So things have evolved from small table top experiments to large scale facilities.
The MAST-U (Mega Amp Spherical Tokamak Upgrade) project is important to the UKAEA because it’s a
major step towards achieving commercially viable fusion power plants that would provide clean,
safe, and abundant energy. MAST-U is focused on solving the key challenge of plasma exhaust,
which is needed to achieve commercial fusion power, and its new plasma exhaust system,
called Super-X, has been designed to reduce heat and power loads,
potentially making diverter components last longer. In my conversation with Fulvio he
mentioned that the diverter is key for commercial power plant designs down the
road because of how it handles the excess heat that’s not used for electricity generation.
“It’s fundamentally the handle of a cup full of hot coffee. So,
our plasma is the coffee that we want to drink. It's what we really want to get, right?”
”Right.”
“We want to get this coffee as hot as possible, but we will not be able to handle it if we were
just holding the cup with our hands. So we need a handle … and the diverter has the same
function. It tries to separate this very hot and very energetic plasma from the surface of
the device. And so we divert our plasma energy. In this version of the device here, the mockup
or up here and on here in this feature. And that component is specifically designed to accommodate
this very large energy device. This design that we have is the most unique in the world. Nobody
else has it. It's called a Super-X configuration. It's just a technical term that we physicists use,
but the idea is that it's specifically designed to accommodate this very large energy.”
“Yeah. I was very curious about the diverter. What made that … because that's
a very significant upgrade from my understanding.”
“Yes, it is. MAST upgrade has already generated extremely interesting physics associated
with this new feature. So, for example, we've been able to see that the energy that is coming
out of the machine is very well handled by this new component. And the performance that we have
observed compared to more standard designs are a factor 10 higher. So this is a really good
result that we have already discussed with the scientific community and we're very proud of it.
And we will also, in the new experiments that we're doing now, we will want to understand how
our plasma is interacting with this new feature of the device. And we are very hopeful this design
will become part of future power plants.” The MAST-U's 'spherical tokamak' design
has the potential to be a cheaper and more efficient means of providing fusion energy
than is currently possible in larger devices. As Fulvio mentioned, the new diverter reduces
the heat of the exhaust material by a factor of 10, making it possible to channel the exhaust
out of the machine at temperatures that the machine's components can withstand.
That should increase the machine's lifespan and economic viability. But in the near term MAST-U’s
whole purpose is to continue experiments and learning how this specific design handles plasma,
increases energy output, and more. The ultimate goal is another big step towards power plants.
“And also the element is super important. These experimental devices are not just for the physics,
they are also to learn how to operate future power plants. How to maintain them,
how to make sure that they are in the proper state. How to improve them. So there is also
an important operational capability building that is done with these experimental devices.”
Which brings us back to JET.
“Woah …. Woah! This is massive!”
“Welcome to the JET tokamak” “Oh my god …”
“Welcome to the torus.” “This is massive.”
“This is my reaction when I did my thesis on a tokamak that was this
big. And the first day I came here I couldn't believe it was this big.”
I can count on one hand the number of times I’ve been blown away like that. One of my
favorite moments was walking into the vehicle assembly building at NASA, where they built
the Apollo rockets, and getting to see one of the space shuttles getting decommissioned. This
ranks right up there … but that was Fernanada Rimini giving me the tour of JET. She’s kind
of a legend in fusion energy research and was instrumental in JET’s recent record breaking
results. So it wasn’t just getting to see JET in person that was awesome, it was getting to meet
people like Fulvio and having Fernanda show me around JET that took it to the next level.
JET has been around since the early 1980’s and has gone through many upgrades and revisions
over time. You can see some of that just by the way it looks. It’s kind of like the house
that Jack built. When I asked Fernanda how JET has stayed relevant for so long,
I thought her answer tied in nicely to what Fulvio was hitting on too.
“One of the biggest advantages of JET is that JET was designed and has always been
operated with the physics and the engineering teams working together.
So you don't just get physicists writing impressions on the wall and engineers in a corner
doing their work there. There really is a dialogue between the two. And this allows the fact that,
for example, when there is a physics breakthrough, like, I'm going into details now, but there was
something discovered in the early eighties. There was the H mode that gives you plasma hotter.
It wasn't quite prepared for that, but because engineering
picked up on it, JET was changed significantly and we could operate in this H mode.”
But it wasn't just the synergy between physicists and engineers that have kept
JET relevant. There’s another thing that’s been taking the world by storm the past year or two,
but has already been playing a role in all fusion research, and that’s AI.
“Do you think AI is playing a big role in what
feels like an acceleration of what we're learning?”
“AI is playing a big role. It will play a big role in the way
we control the plasma and in the way we protect the plasma. So yes, it will.”
“We have solutions that come out and say, oh, maybe we could implement this. Real
time systems right from AI and the physics teams are taking advantage of that. So you can iterate
through simulations quickly. We can do simulations in real time as well. We can do model based
stuff in real time these days, which we couldn't even 10, 20 years ago.”
That’s just one example of why I think it feels like fusion research and startups are accelerating
these days. I mean, there’s a lot of factors, but computer modeling is dramatically accelerating
research. Material science advances are addressing engineering challenges, like superconductors
making smaller, stronger magnets. I’ve touched on that in a previous video about the MIT
spin-off Commonwealth Fusion Systems. There’s a lot of challenging issues getting resolved.
As big and crazy as the JET tokamak looks,
it’s been an essential tool for the scientific community to learn
about fusion reactor designs and how to control plasma and the reactions. They’ve
added components over time to test different aspects of how things work and learn from it.
But the part that kind of blew my mind was that they’re also going to
be learning from JET’s decommissioning, which will be happening in about a year.
“You can be learning from the decommission?”
“Oh, yes, absolutely.”
“I love that.”
“The samples, the first, for example, they will take samples from the tiles that are
inside and analyze them to see what has the effect of the plasma been on them. How is the
material been implanted in the tiles? How far all these things will be? How
are the material changes from the nutrons? How do we handle it? Can
we handle it all with remote handling or will at some point people need to go in.”
“I love that you're learning from every aspect of operating it, learning the skill sets,
how to operate the machine, how to take care of it, how to take it down. I love that.”
“Yes. That will be absolutely, you know, a first in terms of trying to learn as much as possible.”
The UKAEA is really taking a holistic approach toward fusion research. They have a new facility
built that’s currently looking into tritium research, which is a major sticking point
for the future of fusion, and the fuel that most people find the most promising. As of right now,
there’s not enough tritium production in the world to support a commercial power plant,
so that’s another thing to figure out. They’re also partnering with private
companies to support varying approaches for fusion power … they have an incredible
agnostic approach. I’ll be talking about one of those companies in the next video,
First Light Fusion, so be sure to subscribe and turn on notifications to not miss that.
I was incredibly impressed with the size and scope of what the UKAEA is doing to
support the broader fusion industry. I was even more impressed by all the
amazing people I met during my day there. Thanks to Oliver, Leah, Fulvio, Fernanda,
and everyone else I spoke to. This only scratched the surface of what I experienced,
so I’m going to try and get more of this out on the Still TBD podcast and over on my Patreon.
So what do you think? Jump into the comments and let me know. And be sure
to check out my follow up podcast Still TBD where we'll be discussing
some of your feedback. Thanks to all of my patrons, who get ad free versions of
every video. And thanks to all of you for watching. I’ll see you in the next one.