Thorium can give humanity clean, pollution-free energy | Kirk Sorensen | TEDxColoradoSprings

Kirk Sorensen stumbled across thorium while doing research on how to power a lunar community. Thorium is a cleaner, safer, and more abundant nuclear fuel—one that Kirk believes will revolutionize how we produce our energy.

Kirk Sorensen began his work with thorium while working as an aerospace engineer at NASA. In 2010, he left NASA to work as the chief nuclear technologist at Teledyne Brown Engineering. In 2011, he founded Flibe, a company focused on developing modular thorium reactors.

This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at http://ted.com/tedx

It starts all the way back
at the beginning of the universe

14 billion years ago, with the Big Bang
and formation of everything

when everything was just
hydrogen and helium

and a little some other stuff.

But stars and galaxies began to form,

and they were like factories
for creating new elements.

Really big stars formed
and they exploded as supernovae,

and this seeded the universe
with everything heavier than iron

that was born in these final moments
of a supernova explosion.

Now two of the things
that were created in the supernova

are what I want to talk about today:
thorium and uranium.

These were different
because they were radioactive

and they kept some of that energy
from the supernova explosion

stored in their very nuclear structure.

And these materials
along with all the others

came together to form our solar system
and our planet billions of years ago,

and some of this thorium
and uranium, then,

was incorporated into our planet,

sinking to the center of the world
and heating our planet,

generating this energy
that generates the Earth's magnetic field.

And it drives plate tectonics,

and it has spread apart oceans
and pushed up mountains.

And these thorium and uranium

are now incorporated into minerals
all over the world,

but because thorium
has a longer half-life,

it's about three times
more common than uranium.

This is the most rich deposit
of thorium in North America;

it's found in Idaho.

Now as life filled the world
protected by the magnetic field,

they didn't know any more
about the importance of these minerals,

and certainly we didn't
as we entered the scene.

We made our future
out of stones and simple tools

because they were resistant to fire
and they were rugged.

When we were able
to find metals, like gold,

we practically worshiped them

because they were so marvelous and shiny,

but gold was far too rare
to build an industrial civilization -

you know, we couldn't build a plow
out of gold, or armor or spears.

Bronze was the material we wanted to use
because it was much more common.

And the technologies
that allowed us to first smelt iron work

were really what led to many
modern innovations we have today;

iron is still the most commonly used
of all the metals.

In thousands of years of human history,
only seven metals were known.

Chemistry and technology
really began in the 1700s

and was centered in this place,
the Royal Institution in London;

this was a golden age of science.

In the basement of the Royal Institution,
10 elements were discovered -

for instance,

common table salt is composed
of sodium metal and chlorine gas.

In 1829, a Swedish scientist named
Jöns Jacob Berzeliu isolated thorium,

and he gave it this awesome name
named after the Norse god of thunder.

He had absolutely no idea
how well he had named this element;

in fact, it's probably the best named
element in the history of elements.

He didn't understand any of that though.

In 1841, uranium was also discovered
using the same potassium

that had been discovered
in the Royal Institution.

And this fellow
also deserves special mention:

His name is Henri Moissan,

and he was the French scientist
who first synthesized fluorine.

What's special about fluorine?

It's the most reactive
of all the elements that we know of;

it's so reactive, in fact,
we never find it in nature by itself,

we always find it combined
with other things,

like calcium or sodium or so forth.

But the important thing
to understand about fluorine

is when it combines with a metal, it forms
very, very, very stable compounds.

This example is lithium fluoride -
that may sound strange,

but I'll bet a number of you
brushed your teeth this morning

with a fluoride salt
called sodium fluoride.

So if this looks familiar to you,

you're already well acquainted
with this technology.

But one of the most important things
that happened with fluorine

was this gave us the ability, finally,
to synthesize aluminum,

and aluminum became
an incredibly important metal

to our modern world:

We would not have airplanes
and we would not have rockets

if we had not been able
to develop aluminum,

and fluorine was actually the key
to the development of aluminum.

Now in the late 1800s,

this lady, Marie Curie,
was trying to understand

what made thorium and uranium
different than the other elements -

why were they radioactive? -

and she devoted her life
to try to understand this mystery.

Thanks to her work and others',
an understanding of the atom developed,

and it was found to be
kind of like a little solar system -

now physicists might cringe
because it's not exactly right,

but it's mostly right -

that there's a proton

and there's a neutron
and these particles at the nucleus,

and then there's these little
tiny electrons spinning around this.

And this was very important

because this finally helped them

crack the mystery of
"what the heck was radioactivity?"

Radioactivity was a war
going on inside the atom

between the positively charged protons,

that were trying to pull away
from one another,

and the neutrons and protons,

which both exerted a force
called the nuclear force

that helped glue them together.

Radioactivity happened when there were
too many or too few neutrons

for how many protons you had,

and also it explained
why certain elements,

when they got too heavy,

were always radioactive.

This explained thorium and uranium

and, indirectly, why we have energy
from inside the earth, geothermal energy -

all of these things.

It explained why we have the forms
of uranium and thorium we have today.

There's only three natural forms
of radioactive material.

One of them is found in thorium -
it's 14 billion years old -

and then two more are found in uranium.

Now, the part of uranium
that we use for nuclear energy now

is just a tiny, tiny amount;

it's only seven parts in 1000
of the natural uranium is used for energy.

And in 1938, two scientists,
Otto Hahn and Lise Meitner in Germany

discovered that that small amount
of uranium could be fissioned -

it could be split apart

and that released neutrons
and much, much, much more energy.

And this was a great discovery
that thrilled scientists around the world,

but the leadership in Germany
kind of looked at the whole thing as scams

because Meitner was Jewish

and she had fled Germany to Sweden
to escape the Nazis.

But scientists in the United States,

particularly Jewish scientists
that had fled Europe,

were paying very
close attention to this work

and trying to alert the government

the research will probably be going on
in using uranium as an explosive.

So, they knew that they would need to go
and change the amount of uranium

that was this very rare stuff,

and here fluorine
came to the rescue again;

by combining fluorine with uranium -
six fluorine atoms for each uranium atom -

they were able to make uranium into a gas

that was suitable

for increasing or enriching
the concentration of uranium-235.

This whole technology wouldn't have worked
if fluorine had different properties,

but fortunately, fluorine
only has one kind of structure:

nine protons, ten neutrons -
no other kind -

and that's what allows it, in this form,

to preserve that very,
very delicate balance

between the heavier form of uranium
and the lighter form of uranium.

The story for thorium ironically, though,
begins with this fellow:

his name was Glenn Seaborg,
and he was a chemist

at the University of California
in Berkeley in 1939.

He was following the work in Germany
very, very closely,

and he wanted to know

if other elements
could be used for nuclear energy.

He had access to the most powerful
nuclear physics machine in the world;

it was called the cyclotron.

And with this machine,

he was able to bombard
uranium and thorium with neutrons,

and he discovered new elements,
neptunium and plutonium,

and he also discovered
a new form of uranium called uranium-233.

With more work on the cyclotron,

he discovered

that both plutonium and uranium-233
could also be turned into nuclear fuels.

And so in a very short period of time,

Seaborg had discovered a way

to turn all of these nuclear fuels
into potential energy sources,

and this was a discovery that had
profound implications for the world.

Unfortunately, it was discovered
at exactly the wrong time

because this was
the middle of World War II

and everything was being devoted
into a wartime effort.

Before long,

Seaborg was read into a secret program
called the Manhattan Project

and he was instructed to go and use
his discovery of plutonium

to prepare materials for a nuclear weapon.

Not long thereafter,
the Japanese attacked Pearl Harbor

and the United States
was launched into World War II.

Seaborg was also still
very curious about thorium,

so he made sure
one of the first reactors built

was loaded with some thorium so
he could learn more about its properties.

Unfortunately, he wanted to find out if
he could use thorium as a nuclear weapon -

it was wartime.

When the results came back,
he was very surprised;

he found out that fluorine
was really going to be totally lousy

for a nuclear weapon

because the uranium-233
that would be formed

would always be contaminated
with other things

that were going to emit
large amounts of radiation.

But he discovered something

that's still very important
for us to know about today,

which is that uranium-233 had a property

where it could continue
to make enough neutrons in its fission

to create new uranium-233 at an equal
or greater rate than it was consumed.

And this meant that thorium
could be used as a nuclear fuel

that would last essentially
as long as the thorium lasted,

and because thorium was so common,

this meant that we would have
an energy source

that would essentially never run out.

But again, all of these realizations

were swept away by the wartime need
for a nuclear explosion,

and the United States was the only country

that had the technology
for nuclear explosions,

and they had a big secret,

which was that they were out of bombs
after World War II,

and so all of their effort
went into making more nuclear weapons,

they did not put effort into "how can we
go and make nuclear energy?"

There was great controversy
over who should be in charge.

Ultimately, they decided
to create a civilian agency,

but they gave it a military mission.

I say all these things with great regret

because I'm convinced

that had nuclear fission been discovered
at some other time in human history,

we would have had
a very, very different story.

If your introduction
to something is very negative,

you tend to think about it
negatively from then on.

People were not thinking about how to use
nuclear energy for positive purposes

because of the wartime effort,

and so it's one of these great tragedies
of how our history evolved

that nuclear attains
such a negative impression

in people's minds from the outset.

After the war, there was a tiny focus
on making some nuclear energy

using a sodium reactor,

and this was because it had the ability

to make more plutonium
and better plutonium than it consumed.

But this fellow, Alvin Weinberg,
he also was somebody who chose to start.

He chose to start looking at thorium
at the Oak Ridge National Labs

after the war,

and his efforts in thorium were spurred

because he had gotten a contract
from the Air Force

to look at a power source for a bomber -

he wasn't particularly interested
in nuclear bombers,

but he knew it would be a way
to develop a new and advanced reactor.

This was the reactor they came up with
in the Aircraft Reactor Experiment,

and it was the first reactor
to use these fluoride salts successfully.

The reactor program was cancelled,

but at the same time,
another group of industrialists

was looking at using the sodium reactor
and advancing that technology;

they wanted to build a sodium reactor
that would make lots of plutonium,

and they put a lot of money and effort
into building this consortium of utilities

and began building this reactor.

It was completed in 1963

and not long thereafter,
unfortunately, suffered a meltdown

and was very concerning to a lot of people
who were living in Michigan at the time.

At the same time,
Weinberg was designing a reactor

that was completely immune to the idea
of nuclear meltdowns or nuclear accidents.

By using this fluoride salt

and its stability that it had
because of its chemical properties,

they could design a reactor
that wouldn't meltdown

or have any of these problems;

it would operate at low pressures
but yet high temperatures

and have safety features

that were really far in advance
even of anything we have today.

They successfully built
and operated this reactor -

in fact, Glenn Seaborg here
was at the controls of the reactor

when it used uranium-233
as its first fuel load.

They were very pleased
with the success of this reactor in 1969,

but unfortunately, budget cuts
which had been instituted by Richard Nixon

meant that the Atomic Energy Commission

could only go forward
with one kind of reactor.

They didn't choose the thorium reactor
but the plutonium fast breeder reactor.

They wanted to build
another one in the 1970s,

and this program ultimately
went on to be cancelled.

But even after it was cancelled,

they didn't go back and say,
"What about thorium?

Was that a good idea?

Was that perhaps a better choice
that we should have taken?"

To me, this is one
of the great regrets again

that this technology path
was not chosen.

The United States went on to complete
almost 100 nuclear reactors

in the 1980s and the 1990s,

but really, things started to bottom out
in the '90s in the nuclear field -

there weren't new reactors being built;

there wasn't new technology
being developed.

Now we do have two new nuclear reactors
under construction in Georgia,

but we're closing down nuclear reactors
faster than we're opening them.

And we still have an issue:

What will we do
about long-term nuclear waste?

It's an unsolved issue,
and it concerns a lot of people.

One of the great advantages
of the thorium approach

is that thorium does not produce
the long-lived nuclear waste

that the uranium fuel cycle does,

and this is because it starts
from a different position

on the periodic table

and is able to have more opportunities
to consume all of its nuclear fuel

rather than to produce
long-lived nuclear waste.

These fluoride salts that I've mentioned

are an ideal fuel for creating safe,
easily operable reactors

that can use thorium efficiently,

and they can also burn up the kinds
of nuclear waste we've already produced -

they would be very,
very good at this task.

Because they operate at low pressures,

they don't need big containment structures
like existing reactors do,

and this allows them to be built
in factories for a lot less money.

Because we know that we're going
to need to go forward

with producing more energy at lower cost

and creating less pollution and less
and less challenge to our environment.

So I have been working on a design

for a modular nuclear reactor
based on thorium and these fluoride salts

that has got me very excited

because not only will it
produce electricity,

but it will also produce
desalinated water,

and it will also produce
a particular nuclear medicines

that are in great demand.

[Nuclear energy. The dream that failed]
Things like this aren't helpful.

I really think this is totally wrong.

I don't think nuclear
is the dream that failed.

I think what happened was

the way we went in nuclear
was shaped by the wrong influences -

we were shaped by a desire
for things related to war

rather than things related
to energy and electricity

and things that help people.

So, several years ago,

as I was pondering

whether or not I should make this leap
into starting a new company,

I had to really think hard
because I was in a great job -

I loved it -

I had a new baby;

it just really didn't seem
like the right time.

But I found out

that other countries were going forward
with new nuclear reactor technology

using thorium and fluoride salts,

and I really felt like,

unless I made the decision
to start working on this,

it wasn't going to happen -

I've been doing
tech development long enough

to know these things
don't happen on their own,

they happen because
somebody decides to do them.

And so, just a few months
before I got started,

the Fukushima accident happened in Japan,

and I really, again, had to wonder,
Is this the right move to make?

But then, when I considered
the fundamentals

that people would not stop wanting energy,
they would not stop wanting reliability,

and they would definitely keep wanting
to have as clean energy as was possible,

I knew there was no other choice;
I had to go forward.

And it's been tough;
I've learned a lot of things since then.

I've learned that when you're, you know,
36 years old and you got a wife and kids,

you're not exactly the kind of investment

your typical venture capitalist
is looking for.

I might have done better if I wore
a hoodie and ate some more pizza.

(Laughter)

I also realized that nuclear reactors
are not iPhone apps or anything like that.

This isn't the kind
of in-and-out type investment

that most investors are looking for.

So, it's been an eye-opening experience,

but I've met some really great people,

and I've been really grateful
for letters of support that I've gotten

from all over the world -

people who say, "Keep at it.
Keep up the good work.

This will make a difference in our future,
and we will turn out better for it."

And really, if I could just
leave you with my belief

that, you know, each of us
has to make a choice

of what can we do
to make the world the best place.

The best thing I can do for the world
is to be a great dad for my family,

and the next best thing I can do

is to try to use my talents
to bring about an energy source

that can benefit all of us.

And I just want to leave you with the idea

that please use your talents and abilities

and choose to start to make
the best kind of future you can.

Thank you very much.

(Cheers) (Applause)