Nova (1974–…): Season 44, Episode 9 - The Nuclear Option - full transcript

Five years after the earthquake and tsunami that triggered the unprecedented trio of meltdowns at the Fukushima Daiichi nuclear power plant, scientists and engineers are struggling to control an ongoing crisis. What's next for Fukushima? What's next for Japan? And what's next for a world that seems determined to jettison one of our most important carbon-free sources of energy? Despite the catastrophe-and the ongoing risks associated with nuclear-a new generation of nuclear power seems poised to emerge the ashes of Fukushima. NOVA investigates how the realities of climate change, the inherent limitations of renewable energy sources, and the optimism and enthusiasm of a new generation of nuclear engineers is looking for ways to reinvent nuclear technology, all while the most recent disaster is still being managed.

Are you wondering how healthy the food you are eating is? Check it -
In Japan, the bright lights
never stop burning.

The nation has an insatiable
need for energy,

but virtually no natural
resources to generate it.

To meet demand here,
they bet big on nuclear power.

We blindly believed
nuclear plants

were completely safe,
immune from accidents,

and the cheapest
source of energy.

But the meltdowns at Fukushima
Daiichi changed everything.

To avoid another Fukushima,

we should close
all nuclear plants.

Like the rest of the world,

Japan is at a crossroads.

Can they get along
without nuclear?


The price is going to be
very, very high for them.

Wind and solar

are not going to run
the Ginza lights.

How will we power the planet

without wrecking the climate?

If you really do
wish to do something

about climate change,
nuclear is the path.

We don't use nuclear, because we
got freaked out in the '70s.

No more nukes!

There are some innovative ideas

on the drawing boards.

For my generation,

we are much more concerned

about climate change
and global warming.

We're not going
to rule anything out

because the issue
is so important.

But given its checkered past,

how realistic is atomic power?

Are we ready
for the "Nuclear Option"?

Right now on NOVA.

Breaking news...
a violent earthquake

off Japan's northeast coast
has rocked the nation.

A 7.9 earthquake in Japan,
a powerful...

It began with an epic earthquake
at sea...

...which spawned a giant

...a 45-foot high wall of water.

It rolled over the Fukushima
Daiichi nuclear power plant...

...triggering a cascade
of failures.

Three hydrogen gas explosions.

Three meltdowns.

The uncontrolled release of
radioactivity into the ocean

and into the air.

It contaminated
a huge swath of land...

...prompting the evacuation

of more than 100,000 people
in a 12-mile radius.

The worst affected areas,

northwest of the plant,
remain off-limits, abandoned.

No one will be able to live here
for a very long time.

As the groundwater

passes through the plant,
it gets mixed in

with the contaminated water...

It's now been nearly six years
since the meltdowns

at Fukushima.

I've been reporting on this
since it happened.

Six trips in as many years.

I've traveled up and down

the desolate evacuation zone.

We are about a kilometer from
the Fukushima Daiichi plant,

geing particularly high
readings here...

34 microsieverts per hour.

Victims who lost so much in
the earthquake and tsunami

in limbo, unsure when, or if,
they can return home.

I lost three family members...

my mother, my wife,
and my oldest son.

I thought if we fixed the house,

we could return here to live.

I thought that when we left.

But now that I see it,
there's no way, no way.

And many are understandably
opposed to nuclear power.

From now on, I don't want them

to build another nuclear plant
ever again.

That is a sentiment
shared all over Japan.

In Tokyo, the drumbeat
remains steady.

Protesters still
regularly gather

outside the prime minister's
office to demand

a permanent shutdown

of all the nuclear power plants.

The owner of Fukushima,

the Tokyo Electric
Power Company, or TEPCO,

is pushing hard for permission
to restart another

sprawling nuclear power facility
on the west coast of Japan.

The Kashiwazaki-Kariwa
atomic plant is the largest

in the world.

Or was.

Today at KK,

the operators are
simulating disasters.

But the plant remains closed,

like nearly every other nuclear
power facility in Japan.

After the meltdowns
at Fukushima,

TEPCO invested heavily
in safety upgrades here:

a 50-foot-high seawall;

and watertight doors;

on high ground,
a fleet of backup generators

and fire engines;

and a five-million-gallon
holding pond,

designed to keep water flowing
down to the reactor cores

as a last resort.

The price tag...
nearly $5 billion.

Despite all of that,
the provincial governor

is opposed to a restart,

as are most people
who live here.

I have young children.

In my opinion, nuclear plants
should be eliminated.

Honestly, I don't want them
to resume.

With the impact of Fukushima,

I don't want to use nuclear
plants in the future.

Before the Fukushima disaster,

Japan derived 30%
of its electricity

from 54 nuclear reactors.

There were extensive plans
to build two dozen more.

The goal... generate
half of their electricity

with nuclear by 2030.

Now the nation relies

on imported fossil fuels
to fill the gap.

Japan is at a crossroads.

And so is the rest of the world.

How can we answer

the relentless demand
for more energy

without burning fossil fuels,

the chief culprit
in global warming?

Unlike fossil fuels, nuclear is
a potent source of energy

that does not generate
any of the greenhouse gases

like carbon dioxide that
trap heat in the atmosphere,

warming our planet.

A nuclear reactor is fueled
by uranium, an element

that naturally splits apart,
releasing atomic particles

called neutrons.

It's called fission.

And uranium fission
can induce more fission.

When a loose neutron fires
into a nearby uranium nucleus,

the atom becomes unstable
and quickly splits.

Each time an atom splits

it generates heat.

It's used to boil water.

The steam turns turbines,

generating electricity
without releasing

any carbon dioxide
into the atmosphere.

Renewable sources of energy may
seem like safer, simpler ways

to generate carbon-free power.

But without a practical means

of storing what they produce,
are they reliable enough?

We expect electricity on demand.

What happens when the sun
doesn't shine?

What happens when the wind
doesn't blow?

We don't have
a battery technology

that can meet the rigorous
performance requirements

of the grid...
namely, super-low cost

and super-long service lifetime.

But we have so little storage
now that even if it grows

very rapidly, it'll be a long
time before it has a big impact.

We need to have

base load carbon-free power.

And nuclear is a great example
of something that is

base load carbon-free power.

But since the dawn
of the nuclear age...

That signal means to stop
whatever you're doing

and get to the nearest
safe place fast.

...fear of atomic bombs,
radiation, and concerns about

storing the radioactive waste

have made nuclear power
seem too risky.

- No more nukes!
- No more nukes!

No more nukes!

Fukushima is a lesson
in what happens

when these hypothetical risks
become all too real.

It was one of the largest

nuclear power plants
in the world.

Today it is still a busy,
crowded workplace,

but now a dangerous
decommissioning site.

My invitation to see it up close
was unique.

What next?

Does three have a lot?

Yes, yes...

But even with
special permission,

getting inside is not easy,
by design.

Radioactive contamination
has gone down,

but not nearly enough to
dispense with the Tyvek suits,

three layers of socks,

and gloves,

and full face respirators.

4,000 workers endure
the ritual every day.

They work long and hard
without access

to water or a toilet.

It's like being an astronaut
on a spacewalk.

But this mission is
less scripted and rehearsed.

There is no playbook.

The biggest challenge

is that we've never done
anything like this.

No one in the world
has this experience.

Naohiro Masuda

is TEPCO's
Chief Decommissioning Officer...

the man in charge of this
unprecedented cleanup.

It's neither a job he sought,
nor could have imagined

when he began working
for the utility 30 years ago.

My generation joined the company

to generate electricity
with nuclear power.

That was our purpose in life.

So when it comes
to decommissioning work,

I feel there's a bit

of a dilemma, like,
what is our goal here?

And we still need to decide
what we're going to do.

For that, we need to rely
on the knowledge of people

around the world.

He relies heavily on this man.

For them to come out and to
publicly say, "We need help,"

is different for them.

Lake Barrett is one of
a very select group

who has some experience
wi a job like this.

There was an accident
at the Three Mile Island

nuclear power plant...

The Nuclear Regulatory
Commission appointed him

to manage the decommissioning

of Three Mile Island Unit 2
after it melted down in 1979,

releasing a negligible amount of
radiation into the atmosphere.

There's a lot of similarities
between TMI and Fukushima,

and there's also
a lot of differences.

Fukushima is much more complex.

The damage is much greater.

There's three melted cores.

But the fundamentals
of how you address this

and how you recover are similar.

We are now five feet
into the core.

Boy, a lot of debris.

So where is the melted fuel
at Fukushima?

In the type of reactors
that were built there

the uranium fuel sits
inside rods, underwater,

in a steel pressure vessel,

by a concrete and steel
containment structure

inside a reactor building.

All those layers of protection
are there in case

the cooling water stops flowing.

If that happens,

it quickly boils away,
exposing the fuel,

and it melts,
turning into radioactive magma.

Engineers have sent
robotic cameras

into the containment structure
to try to get a glimpse,

but the cameras quickly fail
after they are bombarded

by radiation.

They do know the damaged cores
are inside

their containment structures,
but it is likely

that they melted through
the reactor pressure vessels

onto the concrete floor below.

Is it in one big vertical lump

on the floor underneath it,
or did it come down

and flow like lava in a volcano,
and move out to the sides?

We don't know yet.

Answering the question
won't be easy.

It's just too hazardous to get
anywhere near the melted fuel.

But a team of scientists

and engineers from the Ios
Alamos National laboratory

is helping TEPCO
get some answers.

Channel seven's on?

Channel seven's on.

They are building

a sensing device
that detects muons,

which begin as
subatomic particles

in outer space before reaching
the Earth's atmosphere.

They can be used as a tool

to see the melted uranium fuel.

Muons are stopped...


or deflected, depending on
the density of the matter

they are passing through.

Muons are like heavy electrons.

They don't have
a nuclear interaction.

In this demonstration,
they used muon detectors

to create an MRI-like image

of this half sphere of lead.

At Fukushima,
muon detectors like these,

placed strategically around
the very dense uranium cores,

can work together to pinpoint
the location and shape

of the melted fuel.

The technique works...
in simulations.

We can see where the core was,
we can see the bottom

of the pressure vessel,
and we can see

if there's material
in the core region,

if there's material
that's in the bottom

of the pressure vessel.

And we can actually measure
if there's any uranium there,

if there's a lot of uranium
there, how much is left.

So this is really good news.

The detectors will be run
for months to gather

sufficient data
to give engineers

the sharpest possible picture

inside a lethally
hazardous place

that none of them
can ever visit.

At Fukushima right now,
the most urgent problem

is water...

a steady torrent
of radioactive water.

The plant is wedged between a
mountain range and the Pacific.

When the rain falls,
it flows toward the ocean

on the surface and underground.

The earthquake on March 11, 2011
created numerous breaches

in the basements
of the reactor buildings.

To keep the melted
uranium cores cool,

TEPCO pumps in 100,000 gallons
of water each day.

The water touches the core,

becomes highly contaminated,
and flows out through

these penetrations that are
leaking onto the floor

of the reactor building.

That's where it mixes

with groundwater that has seeped
into the basement.

100,000 gallons of water is
contaminated each and every day.

To keep it from leaking
into the ocean,

they employ a network of pumps,

sending the water
through a series

of huge filtering plants

that use various types
of fine-grained materials

that naturally attract and bind
with radioactive elements.

They remove cesium, strontium,
plutonium and about 60 others.

All that remains is
a radioactive form of hydrogen

called tritium.

Tritium is very hard.

It's in water itself.

That's something that
you just can't remove

by any methods that I know of
in a straightforward way

on that scale.

So they're going to have
to release it.

Dangerous as that may sound,

scientists say the risk
is relatively low.

Tritium was not released

in very high quantities
from Fukushima

relative to what we released

in the atmosphere in the 1960s
when we blew off hydrogen bombs.

There was a lot of tritium
put into our oceans.

So we're going to be adding in

a small amount of tritium
to an ocean

that already has tritium in it.

In the meantime,

they are storing
the tainted water in tanks.

Lots of tanks.

They have to finish

construction of a new one about
every other day to keep up.

A plateau above
the destroyed reactors

now brims with more than
1,000 of them.

They hold more than
264 million gallons of water.

While TEPCO has enough space to
keep building them for years,

it is clearly not
a sustainable solution,

and yet the government has
refused to issue a permit

that would allow the utility
to start draining the tanks.

To get there, they're going
to have to rebuild

the public confidence
that they understand

and trust the people that are
telling them these messages.

And ultimately that people
realize you can't just

keep building tanks forever...
there has to be a limit.

Meanwhile, TEPCO

is desperately trying to reduce

the amount of groundwater
that becomes contaminated

in the first place.

They have encircled
the damaged reactors

with 1,500 pipes
that go 100 feet deep.

They are filled with coolant
that is 22 degrees

below zero, creating a mile-long
underground barrier

of frozen soil.

The hope is it will deflect
the groundwater

away from the melted fuel.

But why ice?


that I was being assigned here,
I had my doubts.

But there are a large number
of buried pipes

and cables around
the nuclear reactor buildings.

So it's not possible
to use a continuous wall

of steel or concrete

The technique is routinely used
on construction sites

to temporarily stabilize
the ground.

But nothing at this scale,
designed to work for years,

has ever been tried before.

My concern is, if you have water

flowing through the site
and you build a barricade,

does TEPCO really understand
where that water goes?

Is it going to go over the wall,
is it going to go

under the wall, is it going to
go around the wall?

In March of 2016,

they turned it on,
but the groundwater

is still seeping in.

No one knows
if it will ever work.

The engineers here face
huge challenges ahead.

The job won't be finished
for 30 or 40 years.

Nothing of this magnitude has
ever been done before.

It can be done, I believe,
with the technologies that exist

and will be developed
as we go forward.

But no, nothing
of this magnitude has ever

been done by mankind.

They are being watched

by a scared, skeptical populace.

And unfortunately,
scientists can offer

little reassurance.

Biophysicist David Brenner
is Director

of the Center for
Radiological Research

here at Columbia University
Medical Center.

In my opinion,
everybody who lived

in Fukushima prefecture
and even outside who got

some very low level
of radiation exposure,

and that's pretty well
everybody, would be subject

to a very small increase
in cancer risk.

But beyond that,

scientists cannot say
anything conclusive about

their long-term risk
of developing cancer

or genetic defects.

The individuals in Fukushima
prefecture want to know,

"what are the real effects
of the radiation

that I was exposed to?"

And we can't give them
the answers that they need,

and that's a really
unfortunate situation.

I personally find it
a very frustrating situation.

About 18,000 people died
as a result of the earthquake

and tsunami on March 11, 2011.

But no one has died

by radiation from the meltdowns.

So, is the lesson of Fukushima
to stop, or to build better,

safer nuclear plants?

Plants that employ a host
of new technologies

that matured long after
most of our current fleet

of nukes was designed?

I think the right interpretation

of the accident at Fukushima
is we should go all out

on nuclear innovation.

If the Japanese had replaced
these elderly plants

with modern plants, Fukushima
wouldn't have happened.

The first reactors

at Fukushima Daiichi
were designed and built

when this technology
was still young.

The Fukushima plant
designed in the 1960s

was literally
a slide-rule-era plant.

You know, there's
a few calculations in that era

they could have done
on a mainframe,

but that mainframe
has less power than...

certainly than you do
in your cell phone.

The design that failed
at Fukushima

is an early model
boiling water reactor.

There are currently 32 reactors
of this vintage

still running in the world.

In all there are about
450 nuclear reactors

generating 11%
of the planet's electricity.

In the U.S., nuclear power
fills about 20%

of the nation's power demand.

The vast majority
of nuclear power plants

were built with technology

and techniques
from the '60s and '70s

and are water-cooled.

Despite steady improvements

over the years,
water-cooled reactors

still have
a serious vulnerability...

a station blackout that stops

the crucial pumps that keep
cooling water flowing.

This is what happened
at Fukushima.

To make fission robust enough
to generate power,

uranium is enriched,
shaped into pellets,

and then stacked into fuel rods.

This ensures
lots of uranium atoms

are close enough to each other
to allow

a healthy chain reaction.

To manage the rate
of the reaction,

control rods
that absorb neutrons

are moved in and out of spaces
among the fuel.

During an emergency shutdown,
or SCRAM, the control rods

are pushed all the way in,
terminating the chain reaction.

The earthquake
of March 11, 2011,

prompted an automatic SCRAM
at Fukushima.

But it also brought down
the crucial transmission lines

that connected the plant
to the power grid.

Then the tsunami waves

wiped out the emergency backups,

the generators and batteries

designed to keep electric pumps

pushing water over the reactor
cores while they cooled down.

Currently, the existing
fleet of reactors use pumps

and diesel generators
and AC and DC power

to provide the cooling
to the nuclear reactor core.

If you lose connection
to the grid,

essentially you have no way
of cooling that core.

Jose Reyes is a nuclear engineer
at Oregon State University.

In the early 2000s,
he and his team

partnered with
Westinghouse Toshiba

to design the prototype

for a new generation
water-cooled nuclear reactor

called the AP1000.

It has an emergency water
reservoir above the reactor.

It is designed
to prevent a meltdown

for as long as 72 hours,

using gravity and convection,
but no electricity.

If the reactors at Fukushima
could have coped for that long,

the meltdowns
would not have happened.

Four of these AP1000s

are now under construction
in Georgia and South Carolina,

and four more in China.

So what you're looking at here

is the reactor vessel
in the center...

But more recently,

Reyes is focused on smaller
and, he thinks, better things.

He is the cofounder

and chief technology officer
for an Oregon-based company

called NuScale.

In our design,

the reactor vessel
sits inside the containment,

and then that whole system,
the containment

and the reactor vessel,

sits underwater underground.

And that's the whole
safety system for this plant.

NuScale reactors are small
and modular...

designed to be operated
in clusters,

completely submerged

in a four-million-gallon pool
of water.

Each can generate
about 50 megawatts

of electricity, enough to power
nearly 40,000 homes.

So 12 of them linked together
could service 450,000 homes,

or about as much
as a conventional

nuclear power plant.

As we've gone through

the patent process, some of the
patent examiners have said,

"This is too simple.

How is this possible that this
hasn't been done before?"

Unlike Fukushima,
where critical coolant pumps

had to keep running
for the reactors to cool down,

NuScale has designed a plant
that requires no pumps

and no electricity at all.

So a lot of these

are tied to actual valves.


Right now, they are still trying

to validate the concept

and clear the massive
regulatory hurdles.

It will take many years, but
NuScale already has a customer,

the Utah Associated
Municipal Power Systems.

The plant will actually be built
across the state line in Idaho,

at the federal government's

nuclear power test site,

a storied place emerging
from a long nuclear winter.

When I came to Argonne in 1963,
I was then 28, 29 years old.

The world was my oyster.

When Chuck Till first came

to the Argonne National

it was a great time to be
a nuclear physicist,

a golden era.

A lot of things had been

but very many had not.

The things that would be

for civilian nuclear power to
be a success

basically had not been explored.

And at Argonne you were
right in the center of it.

Argonne's vast testing site
in the Idaho desert

is ground zero
for nuclear power generation.

More than 50 novel reactor
designs have been built

and tested here since 1949.

It is hallowed ground
for nuclear engineers.

The beginnings of nuclear power
were here.

The beginnings of useful
nuclear power were here.

At 1:50 p.m.
on December 20, 1951,

four 200-watt light bulbs
started burning here

with electricity generated

by the Experimental Breeder
Reactor number 1,

the first-ever
nuclear power plant.

Besides the fact that it proved
splitting atoms

could generate power,

it also demonstrated a very
clever way to do it.

The fuel was cooled
with liquid metal...

sodium mixed with potassium,
which has a low melting point.

It absorbs more heat

and has a much higher
boiling point than water.

It meant the reactor did not
need to be encased

in a thick steel pressure vessel

designed to keep water in liquid
form like a pressure cooker.

It was inherently safer,
or so the scientists hoped.

They built this reactor
to test the concept:

Experimental Breeder Reactor
Number Two.

The Experimental Breeder Reactor
Number Two is a reactor

that's known to all nuclear
programs around the world.

It is a full-scale plant

and it proved all kinds
of firsts in nuclear power.

It's now about five minutes
till test time.

It made history
on April 3, 1986.

One minute until the test.

When they staged a bold

of how a liquid metal reactor
can handle multiple failures.

Three, two, one, start.

In the turbine hall
was an assemblage of people

They had nuclear programs
and they wanted to see this

because the reactors
don't behave this way.

Reactors can't be relied upon
to shut themselves down.

The first demonstration
foreshadowed Fukushima...

a station blackout
and a loss of coolant flow

to the hot nuclear core.


They just shut off the coolant

And, I mean, to do that
in a normal reactor,

you'd have an explosion.

You could see the power
going straight up.

The next thing, of course, was
everybody's head swiveled back

to where we were, the Argonne
people were, wondering,

"Are they running?"

The demonstration went as hoped.

The power trace went up like
that, came down well below

where it had to come down,

and the reactor just quietly
shut itself down.

Deprived of any cooling,

this reactor did not melt down
or explode.

But how?

Remember, to sustain
a healthy chain reaction,

uranium atoms must be close
enough to each other

so the neutron bullets
can hit their targets.

When the liquid sodium
coolant pumps stop,

the temperature initially rises,
expanding the reactor core,

dispersing the uranium atoms.

As a result, the chain reaction
is reduced,

causing the temperature
to go down.

So the laws of physics

and the robust cooling capacity
of liquid sodium metal

bring it automatically
to a safe shutdown.

At the time
of that dramatic test,

Chuck Till thought this was the
dawn of a new era.

He envisioned widespread
commercial use

of sodium reactors
based on this design.


The world was going to need
massive amounts of energy

and here was the way.

There was no doubt.

Sodium-cooled reactors,
properly designed, are safer.

I say that without question.

So why don't we have them?

We were stopped.

There has been
a nuclear accident

at the Chernobyl
atomic power plant.

A few weeks after that

a reactor at the Chernobyl
nuclear power plant

in the Soviet Union blew up
during an ill-conceived test.

Chuck Till's success
was totally eclipsed.

This is a model of the Navy's
first nuclear-powered submarine,

the Nautilus.

But the seeds of the demise
for sodium reactors were planted

many years earlier by this man,

Admiral Hyman Rickover,
the father of the nuclear navy.

This is the reactor,
or the atomic pile.

There is uranium in here.

He selected nuclear reactors
cooled with water

to propel the Nautilus, the
first nuclear-powered submarine.

The design made a lot of good
sense for the Navy.

It was the right mix of size,
simplicity, and safety.

Among other things, sodium
explodes when exposed to water.

The huge Pentagon investment
in the research and development

of this technology gave it a big
leg up on other ideas,

including liquid metal reactors.

About the same time,
President Eisenhower delivered

his famous "atoms for peace"
speech at the UN.

So my country's purpose
is to help us move out

of the dark chamber of horrors
into the light.

He hoped to change the way
the world thought

about splitting atoms,
from bombs to light bulbs.

He wanted to export U.S.
nuclear power technology,

and he was in a hurry
to beat the Soviets.

Adapting the nuclear navy
technology for use on land

offered the fastest path
to market.

In 1957, the first commercial
atomic power plant in the U.S.

opened near Pittsburgh, in
Shippingport, Pennsylvania.

Admiral Rickover
personally oversaw

the design and construction.

Very quickly, reactors cooled
with water became the norm.

For 20 years, utilities went on
a nuclear building binge.

But then in the 1970s,

environmentalists took aim
at nuclear power.

The fear of radiation
and the inextricable link

to atomic weapons
and their proliferation

changed the equation.

Protesters viewed nuclear
power as inherently unsafe,

too complex and costly.

And, indeed, as the safety
regulations increased,

so did the cost of building
the plants.

The Achilles' heel of nuclear
power is that you can't protect

against every
conceivable accident.

You can put a lot of extra
safeguards into place

and really lower that
uncertainty as much as you can,

but that will raise the cost
of nuclear power

when it's already unaffordable.

By the mid-'70s, the atomic
energy party was winding down.

And then came the movie.

This is Jack Goddell.

We have a serious condition.

You get everybody
into safety areas

and make sure
that they stay there.

The China Syndrome premiered
on March 16, 1979.

It is the story of an evil
corporation cutting corners,

leading to a nuclear meltdown.

The number of people killed
will depend on which way

the wind is blowing,

render an area the size
of Pennsylvania

permanently uninhabitable,

not to mention the cancer
that would show up later.

Twelve days later,
in Pennsylvania,

life seemed to imitate art
at Three Mile Island,

the seriousness of the meltdown
there unwittingly embellished

by Hollywood.

Support for nuclear power

Still, in the Idaho desert,

Chuck Till's EBR-2 kept going,
running safely for 30 years.

Mr. Speaker, the President
of the United States!

But it was better
at sustaining fission

than political
and popular support.

The program was canceled by
President Clinton in 1994.

We are eliminating programs
that are no longer needed,

such as nuclear power research
and development.

The whole system,

when it was shut down,
was pristine,

30 years of operation.

What a very unfortunate scene.

But now, more than 20 years

the intensive search
for carbon-free power

is prompting a fresh look
at new nuclear technology.

In the face of climate change

the money is starting to flow
in this direction again.

The federal government
has placed some new bets

on nuclear innovation.

In Idaho, they are taking some
of the old test reactors

out of mothballs.

The fact that we're restarting
that tells us

that we're restarting
a testing infrastructure

to start to develop the next
generation of nuclear power.

Argonne's test site
is now called

the Idaho National Laboratory.

Its director, Mark Peters,
oversees several partnerships

with the private sector
to improve technology,

the state-of-the-art in water
cooled reactors

known as generation three.

But the main goal is to
commercialize generation four.

Generation four are future
reactors that are based

on different concepts,
different core designs,

different coolants.

I'm quite excited about
where we're at today.

And so is his predecessor,
Chuck Till.

It surprises me

when I go on the internet and
see how many allusions there are

to the things that we did.

And I hope that the work
that my colleagues have done

in that decade
from 1984 to 1994 pays off.

The nation has fumbled around,
in my view,

for 20 years unnecessarily.

But now Chuck Till's vision may
finally be gaining

some critical mass.

I'm going to talk today about
energy and climate.

This time one of the drivers
for nuclear power technology

is not an admiral, but rather
a captain... of industry.

And so what we're going to have
to do at a global scale

is create a new system.

Microsoft founder Bill Gates is
among a handful of entrepreneurs

with seemingly bottomless
pockets making big bets

on nuclear power.

At a TED conference in 2010,
he publicly announced

he had co-founded
a company called TerraPower.

Nathan Myhrvold and I
actually are backing a company

that perhaps surprisingly

is actually taking
the nuclear approach.

His partner is his former chief
technology officer at Microsoft,

Nathan Myhrvold.

When we first started investing
in TerraPower

and getting it going,
we had a lot of people come

and look at us, kick the tires.

That was the era when Silicon
Valley was into clean tech.

And they all said, "Oh, my God,
this is risky."

But Bill and I thought
that it being risky

doesn't mean
you shouldn't do it.

In fact, perversely, that's
exactly when you should do it.

It's when everybody else says,
"No, I can't... I can't do it."

It's something that is a risk

that's not for
the faint of heart.

Here they are working
on a 21st-century take

on sodium reactors.

It is designed to run without
reprocessing and refueling.

With the TerraPower reactor,

you fuel it and you don't take
them out for 60 years.

During that period of time,

you'll get enormously more
energy out

than you would get
from the same uranium

if you put it
in a conventional plant.

Unlike water-cooled reactors,

this one does not need the
equivalent of premium gas...

uranium that is refined
to greater potency

in a complex, expensive process
called enrichment.

But the enrichment process
has leftovers.

The biggest stockpile
in the U.S. is here

in Paducah, Kentucky,
at a uranium enrichment plant.

These leftovers,
called depleted uranium,

can be used to fuel
the TerraPower reactor.

If this works, it would be a
game changer for nuclear power,

to store depleted nuclear fuel,
one huge unresolved problem.

With our reactors,
Paducah, Kentucky,

becomes the energy capital
of the United States,

because Paducah alone has enough
of this low-level nuclear waste,

the depleted uranium,

that we could run all of
America's electricity needs

for 750 years.

But TerraPower faces

big regulatory hurdles.

The Nuclear Regulatory
Commission is accustomed

to licensing
water-cooled reactors.

When it comes to innovative
technology like this,

the rules haven't even
been written.

So TerraPower has found
a customer

that is less constrained
by regulation

and public relations: China.

It's where its first plant
will be built.

So far, from a
technical perspective,

we've solved every technical
problem that's occurred.

But I can't tell you, "Oh yes,
we've already been successful."

It's going to be many more years
of hard work

before we are successful.

And stop.

So we made a crazy bet

and we're going to keep making
that crazy bet.

And I'd love to have
more competition.

I'd love to say, "You know,
we're neck and neck"

with three other companies,"

because that's what
moves things forward.

It appears Nathan Myhrvold
will get his wish.

A D.C.-based think tank, Third
Way, conducted a survey in 2015

and found more than 40 startups
across the U.S.

developing advanced
nuclear power designs.

These atomic business plans
have lured

more than a billion dollars
in investment.

I think a lot of it might just
be the changing demographics

of nuclear engineers that
now there are a large number

of young nuclear engineers

who think,
"I have a really good idea.

"I'm going to flesh out this

"I'm going to raise some

I'm going to see if I can do
this on my own."

How much do you have to worry
about free fluorine formation?

Leslie Dewan is one of
the young entrepreneurs

leading this revolution.

Yeah, because that's
what I'm hoping.

It's a new generation
with a different outlook.

Atomic power doesn't carry
the same stigma for them.

They are more concerned about
powering the planet

while addressing climate change.

All of this led Leslie to MIT
to study nuclear engineering.

This is a general trend
around the world.

She was a grad student on the
day the tsunami hit Fukushima.

It was especially shocking to me

because when I first
heard the news,

I thought there are overblown
media reports

but I trust that everything
will be okay.

But it went orders of magnitude
beyond what I had thought

the worst-case-scenario accident
was going to be.

And yet she didn't waver
in her goal to build

a new kind
of nuclear power plant.

It made me want to work even
harder on developing

newer types of reactors
that don't have

the same cooling requirements
and that are even more robust

in the case of even more extreme
accident scenarios.

She became enamored with some
nuclear technology

first developed 50 years ago
at another national laboratory,

this one in Oak Ridge,

It's called
a molten salt reactor.

Not table salt,
liquid fluoride salts.

Unlike the TerraPower reactor
that uses liquid metal

to cool solid uranium fuel,

this inventive design
turns that idea around.

A molten salt reactor
uses liquid fuel

rather than solid fuel.

With liquid fuel,

the size and shape
of the container is crucial.

Pumping the fuel into
a cylindrical vessel

places uranium atoms
close enough to each other

to sustain a nuclear
chain reaction.

If something goes wrong
and it starts to overheat,

the liquid expands

and the uranium atoms become too
dispersed to maintain fission.

So it starts cooling down

And in the case of a total loss
of station power,

like Fukushima, the design
employs another safety feature.

Below the reactor chamber
is an emergency reservoir.

The drain leading to the
reservoir is plugged

by the same salt mixture,

but it is refrigerated
so that it freezes solid.

Without electricity to keep it
cool, the plug quickly melts,

and the liquid fuel drains
into the emergency reservoir.

Unlike the reactor chamber,

the shape and size
of the emergency reservoir

ensures the uranium atoms
are too far apart

to sustain a chain reaction.

It cools down
and eventually freezes.

Crisis averted.

At Oak Ridge,
they successfully ran and tested

a molten salt reactor
for four years.

The design works.

Even in the worst type
of accident scenario,

even if you don't have any
external electric power

like what happened at Fukushima,

even if you don't have any
operators on site,

they're able
to shut themselves down.

The basic science
is well understood,

but building a reactor that can
withstand something as corrosive

as a very hot bath of salt
is a huge engineering challenge.

It is the focus of early testing

for Leslie's startup company,

We can make something that works

for five years,
that works for ten years.

Like, that we certainly know.

What we are trying to figure out
now is whether we can use

newer materials or new methods
of corrosion control

to extend the lifetime
of the facility

because ultimately we care about
making this low cost.

If you have to replace your key
components every ten years,

it's not going to be
cheaper than coal.

And if it's not cheaper than
coal, then it's not worth doing.

But coal and all fossil fuels
carry another cost

to the environment.

In Japan, with the nukes

they have kept the lights

by burning imported
fossil fuels,

mostly liquid natural gas.

The result: a steady increase in
greenhouse gas emissions,

reversing the nation's ambitious
reduction plan

signed just two years
before the Fukushima disaster.

If you're concerned
about climate change,

you need to be open
to nuclear power.

I think that there is no way
that the world will meet

its carbon reduction goals
without including nuclear

in the mix.

All over the world,

the demand for energy grows,

in emerging economies.

China opens a new coal-fired
power plant about once a week.

Can the world respond to the
relentless demand for energy

without worsening
climate change?

Is it time to rethink
the nuclear option?

The fate of the whole planet
depends on us renewing

our energy system with
renewables and with nuclear.

And if we step back from that,

we are going to create
a tremendous problem

for future generations.

This NOVA program is
available on DVD.

NOVA is also available
for download on iTunes.