Hello, and welcome to the Physics World weekly
podcast.
I'm Hamish Johnston.
Nuclear fusion powers the sun, and scientists and
engineers have long been trying to harness the
process to generate clean energy.
While much progress has been made, the commercially
viable generation of fusion energy
remains elusive.
One important challenge is developing a range of
specialized materials
that can contain an extremely hot radiation
emitting plasma
in close proximity
to ultra cold superconducting
magnets.
Our guest this week is Jacob John of
The UK's Atomic Energy Authority.
He studies how radiation damages materials.
And in conversation with Physics World's Mateen Durrani,
he talks about the near oxymoronic
materials requirements
for fusion reactors
and how they can be met.
Hello, Jacob. Welcome to the Physics World podcast.
Pleasure to meet you, Matin. I am really
happy to be speaking with you. Alright. So
let's start with the basics. Do you want
to for listeners, do you want to tell
us a bit about yourself and where you
are? You're in France at the moment, aren't
you?
Yes, sir. So I work for the United
Kingdom Atomic Energy Authority,
and, we serve the British taxpayer.
And I have the honor to represent the
British taxpayer,
in France currently. So in,
in that's in CEA.
That's in
France's,
nuclear energy,
research laboratory.
And,
so so you work in fusion. So before
we get on to exactly what you do,
let's have a quick reminder about fusion power
and, you know, why it's so important for,
you know, the future of our planet and
our energy mix and so on.
Yes. That'd be a pleasure.
So
fundamentally,
what a fusion machine or a fusion power
plant is doing
is transforming
mass into energy.
And,
the energy density of the fuel that they're
working with is so high that realistically,
at our current energy consumption rate rates,
running out is not a concern.
They're they're beautiful machines,
and
and they're very comparable to particle accelerators actually
in this the type of components they use
with cryogenics,
vacuum systems,
the kind of materials.
And
that means in their core, they need a
very precise control. So what you're talking about
is very precise control
over
transforming mass into energy, which if you can
accomplish that,
you know,
the benefits don't need to be described, to
your audience. I know they're very,
scientifically,
kind of aligned.
So
but, yeah, to be able to turn energy
in a mass into energy is great. Yeah.
I mean, it's one of the fundamental things
of, you know, physics, isn't it? So,
a fusion machine, and, you've told me not
to call it a reactor. It's a machine.
And now these are I imagine I mean,
you know, when we have one, they'll be
and they are the ones we have at
the moment are pretty extreme environments.
So what
sort of for those who don't know, what
sort of conditions are typically found there and
and sort of what sort of materials
do we therefore need to survive in those
kind of conditions?
Yes. Lovely. So I would I would like
to start with, where we talked about the,
the machine,
idea. I heard I've heard one I've heard
a I can't remember who is, the leader
of a of a private, fusion company. He
describes them as,
fusion generators.
And,
because really at the end of the day,
where we were talking about,
this precise control over this reaction,
it's
quite quite quite different than
than,
the nuclear power plants that we use today.
And it's important to draw a a a
designation between the two technologies.
So you talked about the extreme environments, and
they are very extreme.
One of the difficulties or
this deep irony of fusion machines
is
that you they perform better
when you take very cold
material,
as cold as you can possibly make it.
When you take very cold material, and bring
it very close
to very hot material. So so the hot
material would be plasma. That's where the,
that's where the, the light atoms are combining
and superheated
very, very hot.
But, of course, we use magnets to control
these reactions as
and, and these magnets have to be kept
cold. So the closer these magnets are to
this very hot plasma, the better con the
better control of the reaction you get. It's
a bit simplistic,
but in their core, they're they're almost oxymoronic
machines.
So we have,
we we need very high temperature resistance,
but they're very different than our existing,
power plants because they're also
very they're also very dynamic,
very dynamic machines. So they're very hot,
but they have rapid fluctuations.
And these,
the combination of the extreme temperature with the
dynamics
is,
it it it presents conditions that we haven't
tested.
And kind of that's where you come in
because you're working on, a plan for something
called the Joule Horovitz
Reactor
Yes.
Which is,
a plan for a machine being built in,
it's, in Cadarache in Southern France. So do
you wanna explain
where is it, when will it open, and
what's it gonna do to help us understand
materials that are relevant to fusion power?
Very yes. So,
the Joules Horrors Reactor is a is a
fission
material test facility
being built in France.
And,
there's a consortium. And in this consortium, different,
countries,
have purchased in the past rights to the
neutrons that come out of this machine.
And, of course, with
with approval from, from those that operate,
they can use these neutrons to test various,
degradation mechanisms or or develop fuels.
So what what we're doing in the Fusero
program, we're collaborating,
with our French collaborators. It's very much an
international collaboration.
We have,
we have, French contributors.
We have our British contributors. But we we
really share what we're doing,
internationally
as often as possible in order to get
feedback and make sure that,
we're collaborating with the right people and that
what we're doing is,
going in the right direction.
So what we're doing in this program, what
we're focusing on are highly
instrumented experiments
that that are testing
material degradation
mechanisms that result
from dynamics.
And this is
during,
neutron radiation. So these types of experiments,
to operate in core, they're,
they're,
how do you say?
Until we really started seriously,
seeking to build commercially viable fusion power plants,
it's hard to come up with the justification
for this,
for these kinds of experiments due to their
expense and difficulty.
But,
with the promise of fusion power plants,
we can justify these experiments. And they they
become necessary.
And and the Fusero program,
so that's got I think you told me
it's got eight different countries involved.
So what how what you know, how did
you go about doing that and what sort
of projects are being lined up?
Yes. So,
it's the Fusira program is a collaboration between
Britain and France.
But
we,
we we wrote a survey
and
we to update our strategy, the Fusero program
has been around for about ten years.
Maybe maybe precisely, I think, eleven years. And,
to update our strategy, we wrote a comprehensive,
summary,
of our existing strategy, and we asked the
community to give us their insights, share us
their insights with what they feel is important,
for for, our, our program to explore.
And, so yes.
We sent it out to about 200,
participants.
Eight I think 13 participants from eight different
countries responded. We have,
got feedback from, privates from private industry, from
academia, and national laboratories.
And, really,
we strengthened our existing strategy, but also
exposed,
a little some areas of focus.
And so in terms of sort of specific,
material questions,
you know, you mentioned things like, tritium and
steel and superconducting magnets. What sort of, what
sort of things are we talking about?
So we're interested in all of it,
but we can't
do all of it.
But, and in in experiment that we're investing
our energy into is one which describes
thermal mechanical fatigue
in a in in core. So that is
we have a sample in the core of
of this, wonderful Jules Horowitz,
material test reactor.
Incredible
machine.
Very, it's it's going to turn on to
answer your previous question, it's gonna turn on
in about ten years.
Very sophisticated machine, and it, will complement the,
the deep the the closing or the plan
closing of the B R 2 reactor, which
might get an extension to not important. But,
they're they're they're they're they're reactors that actually
complement each other.
So
to not get derailed too much,
we're look we're working on the,
the thermal mechanical,
fatigue in core measurements.
So we are
planning to deliver an experiment
of which
precisely measures
and changes or controls
temperature
and mechanical stress of a sample in core.
So that is during very intense neutron irradiation.
And this is a nontrivial thing to seek
to accomplish.
Some other experiments,
of great interest are,
are tritium production, which is essentially
essentially,
fission fuel.
This is this is a,
complicated subject to, to really
to plan around currently.
It's because,
yeah, there's concerns that
must be addressed.
But we're also working on some other,
some other some other experiments. We we're building
some some experimental setups in Marseille right now
where we examine subcritical crack growth of brittle
materials. So this is interesting because windows are,
infusion reactors or essential component,
and they,
they provide,
isolation of the vacuum from from from air,
from,
pressurized
volumes
for diagnostic systems, but they're also subject to
neutron loading and,
and and due to their, changing temperature, fluctuating
mechanical stress. So there there and, really, we
don't we don't know that much about
how,
precise,
material about about how much certain material property
degradation mechanisms such as,
subcritical crack growth in the field of fracture
mechanics
really
changes
with neutron irradiation.
It's accurate to say we don't know if
that mechanism
actually gets worse or better,
under these conditions.
I'm sorry. That was a bit of a
detailed answer.
But how do you, I'm trying to think.
You know, how do you plan these experiments,
something that's not gonna open for ten years?
You know, how do you,
how do you know what's what's gonna work,
or how do you even plan that far
ahead?
That's seems like an insanely long time scale
for these sort of things. So we have
to think we have to think on these
time scales. We have to think about,
what kind we have to choose an experiment
of an appropriate amount of complexity
for ten years of planning.
That said,
the United UKAEA,
and I work in the materials division,
under, Amy Gandy,
and our director is Amanda Quadling.
And we have, and some of my other,
colleagues,
Slava Coccinto and,
Chris Hardy,
we work together,
and we do perform radiations in in other
reactors that are actually that are actually on
today. And so we both build experiments to,
prove,
that to prove out, things that can be
proven out of a reactor. But then we
also have a radiation programs in operating reactors
today
that, that answers some really fundamental questions. And
and you kind of piece all of this
together,
in order to build robust strategies
that,
that inevitably
must be answered at some point. So we're
we're preparing,
for the future. We're thinking ten, fifteen years
out, but we're taking actions
today that give us results today,
to to really try to make,
fusion power plants commercially viable.
I was gonna say, how will that information
that you get from those experiments feed through
to people building commercial power plants? If you
talk to commercial fusion companies, they'll tell you,
you know, we're on the cusp of doing
something, but you're talking ten years ahead. How
how do the time scales fit? So very
interesting question. There's,
at the end of the day, you're you're
you're you're you're asking really the one of
the hardest things to pull off in research,
which is how do you do valuable research
and turn it into outputs that make a
difference?
So we have to,
we have to be aware of
what we intend to do with these results.
Are we going to,
patent our inventions that that that have,
commercial viability?
Are we going to publish our work to
enable other researchers to progress the field?
Are we going to maybe learn something specific
that we then integrate into a commercially viable
or a design of a of of Britain's,
fusion fusion power plant?
There's
there's
we have to be we always have to
be conscious about,
translating
our research into value.
And
and and we have to we have to
know where we're going. So you asked,
how do we make how do we ensure
that what we're doing makes a difference? And
and and I really do think it comes
down to thinking ten years, fifteen years ahead
and knowing where we're going and why we're
doing it. And,
and,
yeah, I guess we'll see we'll see in
ten years if that's valid.
And so you're in Kadesh in France. Obviously,
everyone knows that for the ITER
fusion experimental experiment there. Do you have do
you work together with them? How would how
does the information from what you're planning to
do, how will that fit into
what might go on there at ITER?
Yeah. So, ITER,
I've had the great honor to visit it
three times
in the last, I think, six months. And
each time,
I was shocked how much progress they're making.
There's
very large components being as very large, very
complex
components being assembled and installed today.
This place,
looks like a place where lots of work
is happening. So,
I'm I'm very impressed with that project.
We have the great and and and and
through through doing these amazing things, they they
really have,
they've really exposed
crucial questions that need to be answered.
So we we we've had the chance to,
to,
integrate with, people at various levels in the
ITER program.
And for specific specific,
projects, we would discuss specifications
of theirs,
and how we and and and then how
can we,
change what we're doing
to,
support
the the questions
that they have deemed to be crucial.
So we do have the opportunity to, kind
of collaborate with them,
but they are
in much later phases. So it's maybe less
of a collaboration and more of us learning
from them, from their from their decisions and
and and understanding the things that they're concerned
about and trying to keep us,
on path on the right path.
And the under other interesting thing you mentioned
to me was that the role of, computer
modeling and AI
approaches can play in kind of complementing the
experiments that you're gonna do with when you
come to test materials in a fusion reactor.
So do you wanna tell us a bit
about that?
Yes.
So a very, very,
I'm excited about about,
applying artificial intelligence. Of course,
how you choose to do it, maybe considering
to use local models if you're working with
something
either, of course, choosing not to use a
model if it's, if it's something sensitive.
Using a local model
if,
if if it's if it's if it's wise.
So we have to we have to apply
it in intelligent ways and and and and
be aware of security,
security concerns that that they present. That said,
the technology,
seems
to
seems to offer an opportunity
to accelerate research and development dramatically. Not only
in in the in in in giving giving
researchers access and then and access to information
and what other people are doing much more
easily, enabling them to be more creative. But
just planning and just simple things like planning
and getting projects,
justified
and and and executing projects,
will be so much easier. I'm very excited
about the effect that this will have on
fusion long term.
I
it seems that
that this is that artificial intelligence is almost
an enabling technology for fusion. So this is,
very exciting, a very exciting time to be
in fusion. The the the the the questions
that need answering,
there's so many valuable things to do.
And, with artificial intelligence, you really feel empowered
to, accomplish as much as possible and really
contribute as much as possible
to our shared mission,
that that humans share. It's very a human
thing, to try to,
control,
the,
the the the fusion, the fusion process.
And
on a short very short tangent, but but
something very interesting about the fusion industry is
dating back to when, when tokamaks were being
invented,
during
dating back
quite some time ago,
If fusion the fusion industry in its core
is a very,
a very collaborative,
a very collaborative thing.
And
and,
so
it's it's it's very nice to have the
feeling
that,
you're contributing to humanity's
to humanity's benefit.
And, it's it really is something that I
feel,
you can derive hope from.
So would the AI be a case of,
drawing information from different sources together to give
you a clearer picture of what's happened? Or
would it be about suggesting
new types of experiments or coming up with
ideas for materials to test?
How do you see it happening?
So the funny thing is is I think
it's just a it's just a fundamental
everyone gets more productive.
I think it's just everyone gets
as simple as people get better at writing
emails
to to people actually get better at,
at learning things more quickly.
And these these these small changes compounds.
Even, like,
people write script
more quickly.
And these these things are going to have,
really compounding effects on, on on on on
on our macro scale projects, on the macro
scale effect,
on on the effects will be really, really
interesting to watch over time. So, for me,
my favorite thing is I've always enjoyed writing
numerical solvers. So,
I always enjoyed,
kind of defining mathematical models and then using
partial differential equations
to, to describe the model. And then I
would always write,
numerical solvers.
My preferred preferred language is MATLAB. And they
were always writing numerical solvers to solve these
equations.
But then to do the plotting
and just just, like, just to make the
scripts and make sure there's no bugs takes
a lot of time.
And and and I love doing it, but
now you can do that so quickly. It's
so empowering. It feels so good.
Yeah. No. I can imagine that. I'm just
saying that must be a great great feeling.
Yeah.
But coming back the Fusaro program that you've
been being involved in, you know, so obviously
the question is how, you know, how is
that gonna help the results from the how
will that help
accelerate the timeline towards a working fusion reactor?
I mean, realistically, how would it help?
So we are addressing
some
some pretty fundamental questions. Our our objective with
with with Fusero c, which is characterizing
thermal mechanical fatigue
with,
with plasma facing components.
If we characterize this properly, engineers can make
design decisions
that
enable
the the the machine to operate for longer
periods of time
without shutting off.
It enables us to design materials that can
operate at higher temperatures.
Both of those things have a profound effect
on the economics of the machine.
So by addressing the fundamental
the fundamental questions,
in material degradation,
we are
we we enable ourselves to make machines that
are more financially competitive. And what's interesting about
this is
when you increase
the operating temperature or the outlet temperature of
coolant from a,
fusion machine by
like, let's just say you double it.
This more than doubles the economic
competitiveness
of the machine that you're working with. So
so small changes
have a profound effect.
And, and that's really what we need. We
need a lot of these kind of, like,
nonlinear
increases in performance, and and I think we're
going to see that. And what we really
do need are these these kinds of experiments,
these in situ,
heavily instrumented experiments in material test reactors that
exist today.
And look into the future then,
Jacob.
You know, what sort of technical milestones
do you see,
you're gonna hope to achieve with that Fusero
program in the next few years?
So this this is, like, this is very
dependent
on, on the funding that we get.
But we have plans,
we we have plans to deliver.
We have
detailed plans that we're very confident we can
stick to the time,
to that we can deliver some
some pretty important results inside of four years.
And so
this is this kind of inside of four
years,
that is possible,
assuming we get the funding necessary.
But these kinds of things, I mean, sometimes
you have to spend time,
you know,
sometimes the experiment that you're working with has
to be in the reactor for a year.
So it's like, there's nothing you can't make
it be less than one year. And so
four years is actually,
quite quite,
quite competitive when it comes to
time and durations and delivery.
So we we do want to see changes
and and impacts
as soon as possible,
but we have to be honest with ourselves
that,
what we're trying to do isn't something that
happens quickly.
So that would be four years after the
thing turns on in in ten years' time.
So as I said as I said earlier,
so we are planning for the Jules Horrods
reactor, and there's some experiments that we're developing
that do actually need ten years of experiment,
of development.
But we have plans,
plans we have plans, and there are only
plans right now,
to leverage other machines
to
do something,
do something today. And we we do have
actually have radiation programs going,
today. But what's interesting is when you operate
one one radiation program in one machine, maybe
prove out some experimental concepts, you can then
use it again in a different machine assuming
you have the right agreements in place with
the laboratories that you're working with. Yeah. Given
those long time scales, you know, if if
I was a
a, you know, young student going into, you
know, thinking where to go with my research
career, these are very long term questions.
Some people might want a quicker fix than
sort of things that happen quicker than that.
What do you see as the,
attractions of working in this area if you're
a sort of up and coming scientist or
engineer?
I would say the the best thing about
working in the fusion industry
is,
the people that you get to spend your
time with.
The
it's it's a pleasure to come in every
day and work with people that love what
they're doing, and and every person is excited
to share what they're working on. So,
if that's something that you like doing,
then,
then it's a good place.
But but but I also appreciate what you
say. Like like, my background is actually, I've
I've been interested in I've been my my
first role in in the nuclear facility was
almost ten years ago.
But I have also had in, positions
working in,
other industries
that have very high pressure, very high turnaround,
and I do like that. So
so you're asking a good question.
And I
think
so there's first, there's some private private in
private industries. Some private companies,
depending on how much funding they have, they
do they do build a fair amount of
experiments.
But if you align yourself
with
with if you if you if you present
yourself and you build the skill set of
actually building things, like like,
familiar
with with manufacturing
facilities
and
tolerances and materials and actually
designing and putting things together,
there will be roles for you. And something
that I'm very excited about, with artificial intelligence
is that it's
it's
it accelerates
things
like things like,
things that you would use computers for, but
it doesn't accelerate,
running a mill or running a CNC machine.
And I think what we're gonna see is
more,
more value put onto the production
and the assembly and the actual experiments experiments.
So
I would say,
if you want to be in fusion,
learn physics,
learn,
many many fields in engineering. Don't specialize don't
stick yourself into one like, I studied mechanical
engineering,
but I took extra courses in physics and,
and math and electrical engineering, and and you
can combine these subjects.
But I also,
took a job, working in a manufacturing facility
where, I I I didn't necessarily get paid
to directly use those skill sets. But but
learning learning
from people operating machines, how to build things,
is probably one of the most, complimentary and
valuable,
experiences that I've had. So I would really
suggest for for students,
to study physics, to do PhDs,
but to not shy away from working in
manufacturing facilities.
So have you got any sense before we
finish about, you know, time scales? So when
will we see a
commercial fusion reactor
sorry, machine that's generating electricity into the grid?
That's always the question that everyone wants to
know.
Which which country are you talking about? It
depends. Different countries
are taking different approaches
and
and taking different approaches, and they're kind of
testing out different technology.
So it really does depend who you're talking
about.
I wouldn't
I wouldn't like, I like like, our project,
The United Kingdom's project, our target is twenty
forty.
But, you know,
our technology is different than than other than
other,
than other technologies in other countries. So,
you know, I wouldn't wanna give out a
number,
but, our target is twenty forty, and and
and our and our project is quite comprehensive.
Alright. Okay. So any final message before you
go to people listening?
No. I I,
I wanna thank you for the time to
speak.
I'm I think we should all be very
excited about the future for the fusion industry,
and
those that want to,
enter the fusion industry
should learn
about building things,
about manufacturing.
Yeah. Alright. That's a good note to end
on. Alright. Thanks very much, Jacob. Great to
talk to you, and good luck with your
endeavors.
And I know you're about there it's Friday
afternoon we're recording this, though. You you've got
a couple of hours before you have to
leave. So, thanks for fitting us in. Oh,
it's a pleasure to speak. A great pleasure.
Thank you, thank you for making time, Martin.
That was Jacob John of The UK's Atomic
Energy Authority
in conversation
with Physics World's Matin Durrani.
Thanks to both of them for a fascinating
conversation.
I'm afraid that's all the time we have
for this episode. I'm Hamish Johnston, and our
producer is Fred Iles.
The music for Physics World's podcast is called
one three seven, and it was composed and
performed by the physicist
Philip Moriarty.
We'll be back again next week.