As a futurist, the most common technology criticism I hear - other than where is my
flying car - is that fusion energy has always been twenty years away.
There is some truth to that, but not exactly, we still have not achieved useable fusion
energy as a power source, though that’s partly only because we decided not to use
hydrogen bombs for mining or titanic energy production purposes.
We could have, there was talk back in the day, but the reality is that bombs are the
wrong kind of fusion, and of course they involved fallout.
But a hydrogen bomb does represent a net gain in fusion energy, and we’ve had them since
1952, when the US performed the “Ivy Mike” shot and detonated a staged fusion device
based on cryogenic liquid deuterium.
Ironically this test also provided proof for the existence of two predicted, but at the
time unobserved elements, Einsteinium and Fermium.
But hydrogen bombs don’t provide practical energy we could use for running a light bulb,
rather they destroy power plants so we have since been left with a dream of eventual energy
production, the science is there.
And it’s not unlike the atom bomb, nuclear fission,s plitting an atom as opposed to fusing
two of them together.
The science of the atomic bomb eventually led to atomic energy.
The promise for fusion is the same, where the science of the hydrogen bomb and the sun
to some degree could some day be further harnessed in a very deliberate, and in fact very safe
way to provide a long term and very environmentally clean, cheap energy.
But again, that’s always been 20 years away for many decades now.
And depending on how the development of fusion proceeds, it may yet be 20 years away or potentially
longer.
But there also may be shortcuts, wildcards of sorts that may change the situation dramatically
and perhaps seemingly overnight, more on that in a bit.
So the first thing to tackle is what exactly happened with the recent announcement of a
fusion breakthrough at The National Ignition Facility at Lawrence Livermore in California.
This is a complicated issue as it was widely misreported in the media and does not give
any near future way of providing fusion energy for planet earth.
But it is an important experiment worth an exploration.
How the experiment worked was that scientists encased deuterium inside a very precisely
constructed shell of carbon, essentially in its diamond form, only a few millimeters in
diameter.
Then they bombarded it with multiple laser beams, a technique called inertial containment.
The reaction then bombards the deuterium-tritium fuel with X-rays, heating and compressing
it and implodes and reaches the ignition of a fusion reaction.
The reaction is of very short duration, this is not sustained fusion, and the experiment
itself has been performed over 100 times.
What was different about this particular experiment, still known as a shot in a very cold war sort
of way, is that it produces a net gain in energy, if you measure based on a certain
set of criteria.
In other words it can be said that more energy was released in the reaction than what was
put into it, a matter of 2.05 megajoules of laser light causing a mini-explosion of 3.15
megajoules, so a 54 percent gain.
That’s the value of this experiment; that on a small scale, rather than the huge scale
of a thermonuclear bomb, it was able to release more energy than what it took to set it off.
That’s of great importance in fusion energy because we’re going to need a sustained
reaction that does that, but on orders of magnitude more energy released.
Energy generation isn’t any good if it takes more energy to produce the reaction than what
you get out of it.
This passed that hurdle, at least in a sense, but this was not a sustained reaction.
The problem is that this experiment isn’t really the type of fusion you need for a commercially
operating energy power plant.
Rather this is the type of fusion you need to test nuclear weapons without setting them
off on a large scale.
The need for this is test ban treaties that essentially restrict the testing of nuclear
weapons.
The US for example has not tested a nuclear weapon since 1992, and since then all testing
has been done by computer modeling.
In short, this experiment really represents a way to test miniature hydrogen bombs to
make sure the arsenal at large works, should it ever be needed.
Hopefully not of course, but needless to say, this was not a major advancement in fusion
energy per se, rather an interesting result of an experiment built for different purposes
that one day may, and this is still unclear, have some uses in fusion energy production
but not likely for at least 50 years.
My gut tells me significantly longer.
But hype aside, all hope is not lost because the experiment may spur private investment
into initiatives to develop fusion energy that we can use for power generation.
There have been some interesting strides here, and in particular there are two very promising
fusion experiments that literally are designed to eventually generate power.
And one is a bit secretive, to be sure.
The more famous of the two is ITER, which is an international megaproject designed to
explore fusion energy production on a scale never attempted before.
ITER is being built right now, and is expected to begin some operations in 2025 or 2026,
“first plasma” as it’s known, sort of like “first light” for a telescope.
It works on the concept of magnetic confinement plasma physics, and represents what’s known
as a tokamak reactor.
Tokamak reactors offer what’s generally thought to be our best shot at usable fusion
energy.
They’ve been around for a while, but have proven rather difficult to even achieve break
even energy production.
Early experiments with them showed that they needed to be larger, and that was what ITER’s
intended purpose is.
How they work is that fusion energy needs very high temperatures to allow for the fusion
reaction to occur.
This is hard to do, you need temperatures more at home in a star than here on earth.
But we can do that.
How this can be done is very high temperature plasma, magnetically confined, and in the
case of a Tokamak shaped like a donut or torus.
You can reach those temperatures and magnetically confine that plasma, but you have to do it
very precisely because if you don’t the plasma hits the side of the containment vessel,
drops in temperature and the whole reaction ceases.
That’s a good thing and a bad thing.
The good thing is that it makes fusion energy safe, whenever anything fails, it doesn’t
melt down rather the reaction simply stops.
It also produces far less radioactive materials that a fission reactor, basically they will
produce some short lived radioactivity in some worn out parts of the reactors, but that’s
not really a problem, the half-lives are short.
Nuclear fission however produces spent fuel rods that can be radioactive for very, very
long periods of time requiring expensive storage and the potential for release into the environment.
There are ways to make better fission reactors, and there are better ways to store spent nuclear
waste, but that’s for another video.
The waste of this kind of fusion however is going to be things like helium.
This is a good thing, helium is rare on earth.
It’s inert, so safe to be around.
And we only have a finite geological supply of it, and once it’s released in the atmosphere
it doesn’t stay there, we lose loose helium to space, so having a ready source of helium
in the future from our reactors is an attractive possibility because we’re going to run out
of it geologically.
In fact, we may well run out of usable supplies of helium before we hit fusion in only a few
decades because it’s so freely used, and in addition to party balloons is very important
industrially.
The point is, the waste of a fusion reactor like ITER could be useful.
They also produce tritium in a closed circuit in small amounts, which is radioactive, but
with a short half life and doesn’t present a danger.
So fusion really does present a very clean energy source if we can make it work, and
it’s also a very efficient and potentially cheap source.
This could have far reaching implications for humanity, there are many things we currently
aren’t doing because of the prohibitive cost of energy.
Remove that factor, and not only does your heating bill reduce, but new technologies
will come about that potentially revolutionize human civilization.
So why don’t we have it yet?
The bad thing is that getting the plasma torus just right, confined just so in order to sustain
the reaction has proven extremely difficult.
It’s the current major stumbling block in usable fusion energy.
But even ITER is not a power plant, it’s an experimental reactor.
It’s a test bed to allow us to work with an enormous fusion reactor that we can use
to test technologies and strategies that will lead us to viable fusion energy.
All of the ins and outs that need to be technologically developed for a reactor will be done with
this facility, including ensuring safety.
Successors to ITER are planned to be power plants, but experimental ones, yet designed
to produce electricity in a controlled environment and we probably won’t see those until the
2050’s.
That’s a somewhat long timeline, in this case fusion energy will remain 20 years away
for quite a long while.
But here’s the real question.
What if ITER gets leapfrogged?
Enter Lockheed-Martin.
Since 2010 Lockheed skunk works has been working on an alternative take on plasma based fusion
that might change the equation and bring us to usable fusion energy much faster than many
anticipated.
Known as the CFR or compact fusion reactor or high beta reactor, the idea originally
was to create a 100 megawatt fusion reactor that could be launched into space.
This would be astonishing if they can pull this off.
One major disadvantage in space exploration are the energy limitations.
In the inner solar system you can create space stations like the ISS that use huge arrays
of solar panels to produce the energy you need, but within reason, you end up with only
so much energy production to work with, until you need more solar panels.
The further from the sun you go in the solar system, the less energy you receive so at
some point you have to bring your energy source with you, typically in the form of an RTG,
or radioisotope thermoelectric generator, or in other words a chunk of glowing plutonium
producing heat that can be turned into electricity until it eventually decays too much to be
useful and your spacecraft dies.
All of this has so far been low energy, very efficient, and very limiting in what we could
do.
But launch a fusion reactor the size of a bus producing 100 megawatts of electricity,
and we’ve just hit potential battlestar galactica megaship energy.
Arrays of these reactors could power o’neill cylinders of potentially enormous proportions
with huge populations.
But such reactors chained together could power human cities of any size safely from within
their centers and potentially provide cheap, almost limitless energy to any part of the
world.
If the reactors are cheap enough to make, and the fuel cheap enough to obtain, fusion
reactors would be everywhere benefiting almost the whole of humanity that hungers for electricity.
The idea is to create a kind of contoured rod of plasma rather than a torus that redirects
plasma leaking out of the magnetic fields back into the system using sharply bent magnetic
fields known as cusps.
In short, the more the plasma pushes, the more the confinement pushes back.
It also works with a smaller volume of plasma, which should drop the energy needed to achieve
fusion.
The reactor is designed such that it should create self-sustained fusion indefinitely.
But there are many challenges.
The plasma temperatures are millions of kelvins, hot beyond belief, yet the superconducting
magnets holding it all together have to be kept at near absolute zero, cold beyond belief.
That’s complicated, but theoretically achievable.
And a series of prototypes have been built, with Lockheed becoming increasingly quiet
about the development.
That could be because it’s not working out well, but it could also be that it is working
and that we’re far nearer to usable fusion energy than is generally known.
And they’re not the only ones in the game, there are multiple companies and teams involved
with pursuing these avenues of fusion because frankly, if you can perfect it, you’d make
a whole lot of money.
And you could in principle do it faster than government consortiums, and at much lower
cost.
So it may be that fusion isn’t 20 years away.
It may simply be that it comes out of nowhere from private development, and may do it in
a shorter time frame.
The development of fusion is not in its infancy, rather it’s simply really complicated on
the engineering side and it’s taken years to develop ways to even test how it could
be put into action.
We are after all studying the process that powers the sun, not an easy feat, but the
sun shows us that it is possible in nature to do it.
The physics behind fusion is fully there.
But I ask you this, in the far future if we can create our own sun here on earth, when
in the depths of space, do you think we will need the sun any longer?
Thanks for listening!
I am futurist and science fiction author John Michael Godier currently lamenting the hydrogen,
it’s destiny is to become helium, very objectionable and …
ANNA: John.
JMG: ANNA, I'm making a video here.
You’re supposed to be in the Event Horizon green room working on next week’s year end
episode with Isaac Arthur.
ANNA: I thought you might like to know that the opposum has developed fusion energy as
a weekend project.
You’ll need to wear this safety hat.
JMG: What?
It’s a colander and we’re in the kitchen not a lab.
Look, Humans have been working on this since the 50’s, and he comes along and cracks
it in a weekend?
What’s going on here?
Wait, This isn’t (zap sound).
Wait a minute, that wasn’t fusion, it was an electric shock!
ANNA: Same thing John.
(possum cackles)
JMG: And the possum cackles