The World’s Biggest Fusion Reactor Doesn’t Do Anything

Summary

The script delves into the quest for nuclear fusion as a sustainable energy source, comparing it to the fictional ambitions of 'Spider-Man 2' villain Doc Ock. It explains the difference between fusion and fission, highlights the National Ignition Facility's (NIF) achievements and limitations, and discusses the ITER project's goals and challenges. The video also touches on alternative approaches like the JT-60SA tokamak and the practical considerations for future fusion reactors.

Takeaways

• 🌟 The script discusses nuclear fusion, a process that combines light atoms to release vast amounts of energy, contrasting it with nuclear fission, which is used in current nuclear power plants.
• 🔬 Scientists are pursuing nuclear fusion as a clean energy source, with ITER being the largest experimental reactor, aiming to demonstrate the feasibility of fusion on a large scale.
• 🏗️ ITER, short for International Thermonuclear Experimental Reactor, is a massive international collaboration project that has faced significant delays and cost overruns.
• ⚡ The National Ignition Facility (NIF) achieved ignition in 2022, where the fusion reaction produced as much energy as was put in, but it did not achieve a net energy gain when considering all energy inputs.
• 🔋 Deuterium and tritium are the most common fuels used in modern fusion research due to their lower temperature requirements for fusion.
• 🌐 The script compares two main approaches to fusion: inertial confinement fusion (ICF), like at NIF, which uses lasers to compress fuel, and magnetic confinement, which uses magnetic fields to contain hot plasma.
• 🌐 The JT-60SA tokamak in Japan is a significant step towards practical fusion, designed to contain plasma at extremely high temperatures for extended periods.
• 🔑 The goal of ITER is to achieve a Q value of 10, meaning it would produce ten times more energy than the input, a significant milestone for self-sustaining fusion.
• ♻️ Despite its size and cost, ITER is primarily an experimental facility and not designed for practical electricity generation, making it a testbed for future technologies.
• 🚀 The script highlights the potential of fusion as a nearly limitless, clean energy source, but also acknowledges the substantial technical and logistical challenges that remain to be overcome.

Q & A

What is the significance of the quote from Spider-Man 2 in the context of the script?

The quote from Spider-Man 2 is used metaphorically to introduce the concept of harnessing the power of the Sun, which is what scientists are trying to achieve with nuclear fusion reactors.

What is the main difference between nuclear fission and nuclear fusion?

Nuclear fission involves splitting heavy atoms into smaller pieces to release energy, commonly used in current nuclear power plants. Nuclear fusion, on the other hand, is the process where two light atoms fuse together, releasing a significant amount of energy.

What is the ITER project and why is it significant?

ITER, the International Thermonuclear Experimental Reactor, is the largest nuclear fusion reactor in the world. It is significant because it represents a major international effort to make nuclear fusion a practical and sustainable energy source.

What does 'Q' represent in the context of nuclear reactions?

In nuclear reactions, 'Q' is the ratio of the energy output from the reaction to the energy input needed to initiate the reaction. A Q value greater than one indicates that more energy is produced than was put in.

What is inertial confinement fusion (ICF) and how is it different from magnetic confinement?

Inertial confinement fusion (ICF) uses high-energy lasers to compress and heat a small fuel capsule, causing a rapid fusion reaction. Magnetic confinement, on the other hand, uses powerful magnets to contain and heat plasma, creating conditions for fusion to occur without physical containment.

What is the National Ignition Facility (NIF) and what achievement did it claim in 2022?

The National Ignition Facility (NIF) is a research center where scientists use ICF techniques to achieve nuclear fusion. In 2022, NIF claimed to have achieved ignition, meaning the fusion reaction produced at least as much energy as was put in to start the reaction.

Why is the fuel source for NIF's reactor different from the Sun's?

NIF uses a mix of deuterium and tritium, which are heavy forms of hydrogen, because fusing these isotopes requires lower temperatures and is easier to initiate than fusing regular hydrogen, which the Sun uses.

What is the main challenge in achieving a practical nuclear fusion reaction?

The main challenge is that achieving nuclear fusion requires extremely high temperatures and pressures, and the energy input needed to initiate the reaction must be less than the energy output for it to be a practical energy source.

What is the purpose of the JT-60SA tokamak in Japan?

The JT-60SA tokamak in Japan is designed to test confinement of large volumes of plasma at high temperatures for extended periods, aiming to advance understanding and efficiency of magnetic confinement fusion.

What is the goal of the ITER project in terms of energy output?

The goal of the ITER project is to achieve a Q value of 10, meaning it aims to produce ten times more energy from the fusion reaction than the energy input into the plasma.

Why is the ITER project considered an experiment rather than a practical energy solution?

ITER is considered an experiment because it is not designed to generate electricity for use. Its purpose is to demonstrate the feasibility of self-sustaining nuclear fusion and to provide data for future practical applications.

What are some of the practical limitations for building even larger fusion reactors than ITER?

Practical limitations include the scarcity and cost of tritium, the complexity and expense of the infrastructure needed to operate a large fusion reactor, and the challenges of integrating such a system with existing power grids.

Outlines

00:00

🌞 Nuclear Fusion's Quest for Power

The script begins with a reference to the movie 'Spider-Man 2', highlighting the fictional Dr. Octavius's attempt to harness the power of the sun, which ends in failure. It then transitions to the real-world pursuit of nuclear fusion, a process that combines light atoms to release energy, contrasting it with nuclear fission, which splits heavy atoms. The script introduces ITER, the largest planned nuclear fusion reactor, and discusses the challenges of achieving energy-positive fusion. It also mentions the National Ignition Facility's (NIF) 2022 achievement of ignition using deuterium and tritium, a significant milestone but with caveats regarding the overall energy balance.

05:03

🔋 The Pursuit of Sustainable Fusion Energy

This paragraph delves into the practical applications and current limitations of nuclear fusion. It discusses the inertial confinement fusion technique used by NIF, which involves using laser beams to implode a fuel capsule and initiate a fusion reaction. The script also covers the concept of 'Q', a measure of energy gain in fusion reactions, and clarifies misconceptions about NIF's achievement. It then shifts focus to the tokamak approach to magnetic confinement fusion, exemplified by the JT-60SA reactor in Japan, which aims to contain plasma at extremely high temperatures using magnetic fields. The paragraph also touches on the historical and logistical challenges of the ITER project, emphasizing its experimental nature and the scientific community's hope for its success.

10:03

🚧 The Future of Fusion and Its Challenges

The final paragraph addresses the future of fusion technology and the practical considerations of scaling up reactors. It explains that ITER, despite its size and cost, is primarily an experimental project to advance fusion knowledge. The script discusses the limitations of using deuterium-tritium reactions due to tritium's scarcity and the infrastructure required for a fusion reactor connected to a power grid. It concludes by drawing parallels between ITER and other large-scale scientific projects designed to understand the universe, emphasizing the importance of such experiments in the pursuit of a fusion-powered future.

Keywords

💡Nuclear Fusion

Nuclear fusion is a process in which atomic nuclei combine to form a heavier nucleus, releasing vast amounts of energy in the process. It's the same reaction that powers the Sun and stars. In the context of the video, nuclear fusion is the primary focus, as scientists are striving to replicate this process on Earth to create a near-limitless source of clean energy. The video discusses the challenges and the potential of harnessing the power of the Sun through controlled nuclear fusion reactions.

💡ITER

ITER stands for International Thermonuclear Experimental Reactor and is an international research and engineering megaproject aimed at demonstrating the scientific and technical feasibility of nuclear fusion as a source of energy. The video highlights ITER as the largest nuclear fusion reactor in the world, emphasizing its role in advancing fusion technology and the scientific community's hope that it will be the first fusion reactor to achieve self-sustaining reactions.

💡Deuterium and Tritium

Deuterium and tritium are both isotopes of hydrogen. Deuterium has one proton and one neutron, while tritium has one proton and two neutrons. These isotopes are used as fuel in fusion reactions because they can be made to fuse under certain conditions, releasing energy. The video explains that these are the most commonly used fuels in modern fusion research due to the relatively lower temperatures required for their fusion compared to other isotopes.

💡Inertial Confinement Fusion (ICF)

Inertial confinement fusion is a method of achieving nuclear fusion by heating and compressing a fuel target, typically in the form of a small pellet containing fusion fuel. The video describes how the National Ignition Facility (NIF) uses ICF, where they fire 192 laser beams at a capsule filled with deuterium and tritium to create the extreme conditions necessary for fusion. This method is contrasted with the more common magnetic confinement approach used in reactors like ITER.

💡Magnetic Confinement

Magnetic confinement is a technique used to achieve nuclear fusion by using magnetic fields to contain and control plasma, the hot, ionized gas in which fusion reactions occur. The video discusses how magnetic confinement creates a concentrated blob of super-hot plasma, which is maintained at temperatures far higher than the core of the Sun. This method is exemplified by tokamak reactors, such as ITER, which use strong magnetic fields to contain the plasma.

💡Tokamak

A tokamak is a toroidal (doughnut-shaped) chamber that uses magnetic fields to confine plasma in a toroidal plasma configuration. The video mentions that building a larger tokamak can increase the efficiency of fusion reactions, as it allows for more fuel to be contained and heated to the necessary temperatures for fusion. The JT-60SA, a tokamak reactor in Japan, is highlighted as a significant step towards achieving self-sustaining fusion reactions.

💡Q Value

The Q value in the context of nuclear fusion refers to the ratio of the energy produced by the fusion reaction to the energy input required to initiate the reaction. A Q value greater than one indicates that more energy is produced than was put in, which is a key goal for practical fusion power. The video notes that while NIF achieved a Q value greater than one, it did not account for all the energy inputs, such as the electricity required to power the lasers.

💡Self-Sustaining Fusion

Self-sustaining fusion refers to a fusion reaction that produces enough energy to maintain the high temperatures and pressures necessary for the reaction to continue without external input. The video discusses the aspiration for ITER to achieve self-sustaining fusion, meaning it would generate more energy than is needed to keep the reaction going, which is a critical milestone for practical fusion power.

💡National Ignition Facility (NIF)

The National Ignition Facility is a large-scale laser fusion research facility in the United States. The video mentions NIF's achievement of ignition in 2022, where they managed to get a fusion reaction to produce at least as much energy as was put in to initiate the reaction. However, it also points out that when considering all energy inputs, including the electricity to power the lasers, NIF's energy output was significantly less than the input.

💡JT-60SA

JT-60SA is a fusion research reactor in Japan, which is a tokamak designed to test the technology and physics that will be used in ITER. The video highlights JT-60SA as the world's largest fusion reactor at the time of its activation in 2023, capable of containing a large volume of plasma at extremely high temperatures for extended periods. The reactor's research is aimed at advancing the understanding and technology needed for practical fusion power.

Highlights

Otto Octavius' invention in Spider-Man 2, which was intended to harness the power of the Sun, ended up at the bottom of the Hudson River.

ITER, the International Thermonuclear Experimental Reactor, is the largest nuclear fusion reactor in the world, aiming to achieve self-sustaining nuclear fusion.

Nuclear fusion is the process where two atoms fuse together, releasing a significant amount of energy, contrasting with nuclear fission which is commonly used in current nuclear plants.

Achieving nuclear fusion is challenging due to the high energy input required to initiate the reaction.

In 2022, the National Ignition Facility (NIF) achieved ignition, where the fusion reaction produced as much energy as was put in, although not accounting for the total energy used.

NIF uses deuterium and tritium as fuel, which are heavy forms of hydrogen and are commonly used in modern fusion research due to their lower fusion temperature requirement.

Inertial confinement fusion (ICF) is a technique used by NIF, involving the use of 192 laser beams to compress a fuel capsule and initiate a fusion reaction.

The Q value in nuclear reactions represents the ratio of energy output to energy input, with NIF achieving a Q of 1.54, but only accounting for the energy directly provided by the lasers.

ITER is not designed to generate electricity but to test the feasibility of self-sustaining fusion reactions for future power generation.

JT-60SA, another tokamak, was activated in 2023 in Japan and is designed to contain plasma at extremely high temperatures for extended periods.

Magnetic confinement is an alternative to ICF, creating a super hot plasma contained by powerful magnets rather than physical barriers.

Tokamak reactors, like ITER, become more efficient with size, theoretically increasing the Q value and the potential for energy gain from fusion.

ITER's goal is to achieve a Q value of 10, releasing ten times more energy than is input into the plasma.

The practical application of fusion energy is still a challenge, with ITER serving as a significant step towards understanding the feasibility of fusion-powered future.

Future fusion reactors may need to overcome the scarcity and expense of tritium, as well as the infrastructure required for integration with power grids.

ITER, like other large-scale scientific projects, aims to advance our understanding of the universe and pave the way for potential technological breakthroughs.

Transcripts

Prepare yourselves everybody,

I’m about to quote

the greatest superhero movie ever made:

“The power of the Sun…

in the palm of my hand.”

Unfortunately for Otto Octavius,

and spoiler alert anyone

who hasn’t seen Spider-Man 2,

his invention wound up

at the bottom of the Hudson River.

But two decades later,

scientists are still chasing  the nuclear fusion dream.

They’re not building machines

that house a miniature Sun, though.

Oh no. Real fusion reactors

are way more complicated.

And if you want something

that can supply a steady stream of nuclear energy

to the masses, you have to make it big.

This is ITER,

the largest nuclear fusion reactor in the world.

Or at least it will be when  engineers finish building it,

and scientists finally turn it on.

But here’s another spoiler alert:

it’s going to be about as useless

as Doc Ock’s creation.

And that’s okay.

[intro jingle]

As the name implies, nuclear fusion happens

when two atoms get so close

they wind up fusing together.

And for atoms lighter than iron,

this winds up releasing a ton of energy..

It’s kind of the opposite of fission,

which is what people are usually talking about

when the phrase “nuclear energy” comes up.

That’s what all of Earth’s

current nuclear plants are doing…

cracking atoms

that are heavier than iron into smaller bits

in order to release energy..

And sure,

fission can provide a ton of power…

But kilo for kilo,

it’s peanuts compared

to what you can get with fusion.

Hence the allure to both real scientists

trying to save the world’s energy needs…

and supervillians with robot arms.

But there’s a reason this  kind of nuclear technology

seems stuck in science fiction.

Getting atoms to fuse together

is, like, really hard,

which means you need to pump

a lot of energy into the system.

And there’s no point

in having a fusion power plant

that can’t get more energy out than you put in.

But scientists are slowly making headway,

especially in the past few years.

Back in 2022, researchers

at the National Ignition Facility, or NIF,

managed to achieve what’s known as ignition.

That means their fusion reaction

produced at least as much energy as they put in

for the fusion to happen in the first place.

I do have to put an asterisk on that, though,

which I’ll get to, later.

Now, these NIF researchers

hadn’t quite harnessed “the power of the Sun,”

because they didn’t use the  same kind of nuclear fuel

that the Sun does.

Instead of your standard

just-one-proton-in-a-nucleus hydrogen,

they used a mix of deuterium and tritium.

These are both heavy forms of hydrogen.

Each deuterium nucleus has a proton and a neutron,

and each tritium has a proton and two neutrons.

And together,

they’re the most commonly used fuel

for modern fusion research.

That’s because fusing  deuterium and tritium together

requires the lowest temperature,

so it’s the easiest one to get popping off.

But the fuel source

isn’t the only way NIF’s reactor

isn’t like a mini Sun.

Humanity doesn’t have the mass of an entire star

to gravitationally smush hydrogen nuclei

close enough to get fusion going,

so we have to get our

extreme pressures and temperatures elsewhere.

In NIF’s case,

we use a technique

called inertial confinement fusion,

or ICF.

As the name implies,

you want to create a situation

where your nuclear fuel gets  confined by its own inertia.

And to do that,

the NIF team puts a little capsule

filled with deuterium and tritium

into the middle of a very large chamber,

and then fires 192 laser beams at it

until the fuel reaches star-like temperatures.

The capsule violently implodes,

triggering a fusion reaction

that races through the capsule faster

than the atoms inside it

can get out of the way.

That’s the inertia part.

The deuterium and tritium atoms are,

roughly speaking,

at rest before the implosion,

so they want to stay at rest.

Ultimately, that means

you get a bunch of teeny-tiny nuclear explosions,

which everyone crosses their fingers

to see if they can collectively release

more energy than was put in.

And in 2022,

that was the story you may have heard in the news.

Maybe you even heard

more than one kind of jargon being used:

NIF hadn’t just “achieved ignition”,

it had also “achieved a Q greater than one!”

That’s because in the nuclear world,

Q is basically the ratio of the energy

you get out of reaction

to the energy that was put into it…

asterisk.

But what a lot of those news sites

didn’t clarify was that Q doesn’t account

for all of the energy involved

in a fusion reaction.

In NIF’s case,

it’s just the energy directly provided

by the lasers to kickstart the reaction.

And when you account for the energy NIF

had to pull from the grid to power the lasers…

the amount of energy the team got out

was only like 1% of the energy they put in.

But not only is NIF

nowhere near producing net positive energy,

it’s also nowhere near producing enough energy

to power, well, anything.

I mean, that’ll happen when your fuel cell

is the size of a pencil eraser… So across the world,

other scientists are investigating

an entirely different technique

to achieve a self-sustaining fusion reaction…

one capable of powering itself

so you don’t have to keep pumping energy into it,

but can keep getting energy out.

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Now back to the show.

to the other major form of fusion experimentation:

magnetic confinement.

Instead of creating a bunch of little explosions,

magnetic confinement creates

a concentrated blob of super hot plasma.

And by super,

I mean something like 100 million Kelvin…

ten times hotter than the core of the Sun.

There’s no solid material on Earth

that can hold something that hot.

But since all the particles

in a plasma have an electric charge,

you contain it without touching it

by using very powerful magnets.

And back in the 1950s,

some incredibly whimsical Russians

named one kind of magnetic confinement reactor

a “toroidal chamber with magnetic coils.”

Eventually,

that got shortened to what everyone

calls this kind of nuclear fusion tech:

A tokamak.

And here’s the kicker,

building a bigger tokamak doesn’t just mean

you can fill it with more nuclear fuel.

It also gets you more efficient fusion.

In other words,

it increases that aforementioned Q value…

at least in theory.

So the largest fusion reactor in the world

is one of these tokamaks.

But I’m not talking about ITER. Remember,

it’s still under construction.

[optional: This episode is a road  trip through fusion reactor research,  

and we’ll get there when we get there.]

I’m talking about the JT-60SA ,

which was first activated in October of 2023.

Located in Naka, Japan,

this record-holding tokamak clocks in

at 15.5 meters tall and 13.5 meters wide.

It was designed to constrain  140 cubic meters of plasma

at a temperature of 200 million degrees Celsius

for up to 100 seconds

Now, unlike NIF’s reactor,

the JT-60SA doesn’t fuse  deuterium and tritium together.

Tritium is both expensive and radioactive.

So even though your regular,

run-of-the-mill hydrogen

is way harder to fuse,

that’s what these researchers  have started working with.

Eventually, they’ll do some tests with deuterium.

But all of this research is really meant

to be a stepping stone to more important projects…

…Including, yes,

the project that comes up when you search

what the world’s largest fusion reactor is.

ITER stands for

International Thermonuclear Experimental Reactor.

It also means “journey”

or “the way” in Latin…

But I like to think it stands for drama.

Because hoo boy has this project’s history

been steeped in drama.

ITER originated back in the ReaganGorbachëv days.

By which I mean then-General Secretary Gorbachëv

proposed to President Reagan

that the USSR and USA

should collaborate on  developing fusion energy tech

and not, you know,

use it to blow each other up.

But that agreement was made in 1985.

Four decades and over 20 billion dollars ago.

And for all you space nerds out there,

unfortunately,

it seems the project is pulling

from the James Webb Space Telescope playbook.

Between 2006 and 2015,

the start-up date was roughly a decade away.

Then, ITER’s project managers

finally settled on 2025 as the deadline.

But time crept forward…

and forward...

And while we were putting this episode together,

ITER pushed the dates back once more.

They hope to turn the reactor on

for an initial round of plasma research in 2034,

but won’t actually start fusing

deuterium and tritium together until 2039.

But all you space nerds

know that JWST was worth the wait.

So the question is,

will ITER be just as revolutionary?

Well when it’s finished,

it’ll be capable of holding

about 840 cubic meters of plasma.

Or six times more plasma than  the current record holder.

And with that much plasma,

scientists are hoping ITER

will become the first fusion reactor

to be self-sustaining.

See, whatever your fuel source,

and however much you have of it,

one of the main products

you’re going to get out of a fusion reaction

is heat.

And as much as it’s hard to deal with,

heat is also a good thing.

Because it’s what lets the reaction… react.

So with 840 cubic meters of fuel,

ITER should create enough heat

to keep that fuel at that fusion-promoting

100 million Kelvin,

without any outside boost.

Of course,

scientists first have to turn the reactor on

and see what Q can they get.

The current record from NIF is about 1.54.

But ITER’s rather lofty goal is a whopping 10.

That means researchers expect ITER

to release 10 times more energy

than what they put into the plasma.

Whether or not they can get more energy

out than what they need

to fully power the reactor?

Well, we’ll have to see.

But after ITER makes all that energy,

what are we going to do with it?

A whole lotta nothing,

at least practically speaking.

ITER is not being built to generate electricity.

The neutrons created as the deuterium and tritium

fuse together will slam

into the inner reactor shielding

and heat things up…

…and the excess heat

will just be vented into  the environment instead of,

oh I don’t know, boiling water and using the steam

to turn a turbine like all of our  existing nuclear power plants.

So as massive a project as ITER is…

both in terms of physical scale and budget…

it’s ultimately just an experiment

to get things moving in the right direction.

It’ll be up to the next  generation of fusion reactors

to test how we can transition to generators

that’ll power our homes and whatnot.

According to some proposals,

one or more of these future reactors

could be up to 50% larger than ITER.

But anyone trying to one-up

the world’s largest fusion reactor

will quickly run into some  serious practical limits.

For one, if you plan on sticking

with deuteriumtritium reactions,

you’ve got to worry about

the whole  tritium-is-very-rare-and-expensive thing.

And for another,

you have to account

for the extra infrastructure it takes to operate

not just a giant fusion reactor,

but one hooked up to a power grid.

The bigger they are,

the more complicated and more  expensive that’s going to be.

So ITER itself isn’t going to save the world.

But this isn’t the first time

we’ve spent a bunch of time, money,

and effort building a big, fancy machine

that’s basically just meant to figure out

how the universe works.

Look at JWST.

Look at the particle accelerators at CERN.

ITER will help us understand

just how realistic a fusion-powered future is.

But scientists?

Maybe don’t build an experiment

that you have to contain

by plugging a set of artificially  intelligent metal tentacles

into your brainstem.

[ OUTRO ]