in Japan the bright lights never stop burning the nation has an insatiable
need for energy but virtually no natural resources to generate to meet demand
here they bet big on nuclear power in pizza we blindly believe nuclear plants
were completely safe immune from accidents and the cheapest source of
energy but the meltdowns at Fukushima Daiichi changed everything
jason'll ultimately school 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 sure the price is gonna be very very high for
them wind and solar are not going to run the games of lights
how will we power the planet without wrecking the climate if you really do
wish to do something about climate change and nuclear is the path we don't
use nuclear because we got freaked out in seven there are some innovative ideas
on the drawing board for my generation we are much more concerned about climate
change and global warming we're not going to rule anything else 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 brought a
7.9 earthquake in Japan oh it began with an epic earthquake at sea
which spawned a giant tsunami a 45 foot high wall of water talk about your path
on a dodgy
it rolled over the Fukushima Daiichi nuclear power plant triggering a cascade
of failure 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 a hundred thousand people in a 12 mile
radius
worst affected areas northwest of the plant remain off-limits abandoned
no one will be able to live here for a very long time passes through the plant
it gets mixed in with the contaminated water it's now but 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 getting
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 cookies I lost three family members my mother my wife and my oldest son kya
de Vionnet Donna I thought if we fixed the house we could return here to live
it doesn't do that 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 remained steady protestors
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 kawasaki cara atomic plant is the
largest in the world or was today at kk the operators are simulating disasters
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 5 million gallon holding pond
designed to keep water flowing down to the reactor cores as a last resort the
price tag nearly 5 billion dollars
despite all of that the provincial governor is opposed to a restart as our
most people who live here and what that distinction she said I have young
children is officiating in my opinion statistical nuclear plants should be
eliminated in society oh my mother that was correct and
honestly what the author's I don't want them to resume this one I've had to go
wrong with the impacts of Fukushima I don't want to use nuclear plants my
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 trapped 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 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
wind and solar have been growing rapidly 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 baseload carbon free power
but since the dawn of the nuclear a signal means to stop whatever you are
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 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 is
3 a lot too 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 phase respirators four thousand 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 what about the human the biggest challenge is that
we've never done anything like this month ago you thought okay no one in the
world has this experience now Hiro 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 oh why do I don't know today my generation join the company to
generate electricity with nuclear power we cannot through yoga that was our
purpose in life it's gonna I don't know a little tidal so when it comes to
decommissioning work I feel there's a bit of a dilemma like what is our goal
here at the ground or not 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 with a job like this
it 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 two 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 milk of course but the
fundamentals of how you address this in highly recovery are similar we are now
five feet into the core or 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 under water in a steel pressure vessel surrounded 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 on to 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 you 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 Los Alamos National Laboratory is helping TEPCO get some answers 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 nuan's are stopped slowed or deflected
depending on the density of the matter they are passing through humans 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 new on 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
this material it's in the bottom of the pressure vessel 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 rain falls it flows toward the ocean on the surface and underground the
earthquake on March 11th 2011 created numerous breaches in the basements of
the reactor buildings to keep the melted uranium cores cooled
TEPCO pumps in 100,000 gallons of water each day the water touches the core
becomes highly contaminated and flows out through these annotations 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 they use various types of fine-grain materials that naturally
attract and bind with radioactive elements they remove cesium strontium
lutonium and about 60 others all that remains is a radioactive form of
hydrogen called tritium
tritium is very hard is in water itself that's something that you just can't
remove by any methods that I know of in the 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 release 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 20 minutes 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 a thousand 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 drain
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 like 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 ground water away from the melted fuel but why ice Oh No
cuckoo Tony when my boss told me 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 underground it 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 it's
going to go under the wall it's going to go around the wall in March of 2016 they
turned it on but the ground water 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 know 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
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 11th 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 and cat food I think
the right interpretation of the accident at Fukushima is we should go all out on
nuclear innovation if the Japanese had replaced the 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 the final 1960s was literally a
slide rule you're a plant there's a few calculations in that year
they could have done on a mainframe but that mainframe has less power than
certainly than you do 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 percent of the planets 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
our 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 cool down currently the existing fleet of reactors
use pumps and diesel generators in the AC and DC power to provide the cooling
to the nuclear reactor core the alou's 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 ap1000 s 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
co-founder and chief technology officer for an oregon-based company called
new scale 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 point new scale 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 serve as 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
examiner's 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 new scale has
designed a plant that requires no pumps and no electricity at all okay right now
they are still trying to validate the concept and clear the massive regulatory
hurdles it will take many years but new scale 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 premiere
nuclear power test site a storied place emerging from a long nuclear winter when
I came to our gun in 1963 I was then 28 29 years old the world was my oyster
when Chuck till first came to the Argonne National Laboratory it was a
great time to be a nuclear physicist a golden era a lot of things had been
discovered but very many had not the things that would be necessary for
civilian nuclear power to be a success basically had not been explored and that
our gun you were right miss entered with Argon's vast testing site in the Idaho
desert is ground zero for nuclear power generation more than 50 novel reactor
designs had 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 20th 1951 for
200 watt light bulbs started burning here with electricity generated by the
experimental breeder reactor number one the first-ever nuclear power plant
besides the fact that it proves 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
now about five minutes so last time it made history on April 3rd 1986 one
Minnesota press when they staged a bold demonstration of how a liquid metal
reactor can handle multiple failures
in the Turbine Hall was an assemblage of people that came from all over the world
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 and they just shut off the coolant
supply and I mean do that in the normal reactor you'd have an explosion you
could see the power going straight up
the next thing of course is everybody had twiddled back to early where they
are going people with 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 reactors is 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 absolutely 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 of the turn of atomic power a few weeks after
that demonstration a reactor at the Chernobyl nuclear power plant in the
Soviet Union blew up during an ill-conceived test Chuck til 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
the reactor or the atomic pile there's 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 bags he wanted to export US
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 the 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 the 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 the Veck 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
Adel we have a serious condition you get everybody into safety areas and make
sure that they stay there a China Syndrome premiered on March 16th 1979 it
is the story of an evil corporation cutting corners leading to a nuclear
meltdown the number of people killed with depend on which way the wind is
blowing render an area the size of Pennsylvania is remanent ly
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 evaporated still in the
Idaho desert Chuck tails EBR to kept going running safely for thirty 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're eliminating
programs that are no longer needed such as nuclear power research and
development the whole system when we shut down was pristine thirty years of
operation what a very unfortunate scene
but now more than twenty years later the intensive search for carbon-free power
is prompting a fresh look at new nuclear technology in the face of climate change
reality 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 Argon's
test site is now called the Idaho National Laboratory it's 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 3
but the main goal is to commercialize generation for generation for our future
reactors that are based on different concepts different core designs
different coolers 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 illusions 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 for my view for 20 years unnecessarily but now
Chuck Hills 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
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 Terra power I need the Merville
than I actually are backing a company that perhaps surprisingly is actually
taking the nuclear prote his partner is his former chief technology officer at
Microsoft Nathan Myhrvold when we first started investing in Terra power and
getting it going we had a lot of people come and look at
us kick the tires that was the Europe and 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 here they are working on a 21st century
take on sodium reactors it is designed to run without reprocessing and
refueling for the chair bioreactor if you lit and you don't take them up for
60 years during that period of time you'll get enormous Li more energy out
then you would get from the same uranium if you put it in the 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 and a uranium enrichment plant
these leftovers called depleted uranium can be used to fuel the Terra power
reactor if this works it would be a game-changer for nuclear power in part
because it would virtually eliminate the need 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 that is rhenium that we could run all of America's
electricity's 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 Terra Power 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 so we made it
crazy back and we're going to keep making it crazy back 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 DC 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 technology I'm going to raise some
funding I'm going to see if I can do this on my own how much you have to
worry about Freeport formation Lesley Diwan is one of the young entrepreneurs
leading this revolution 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 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 Tennessee it's called a molten
salt reactor not table salt liquid fluoride salts unlike the Terra power
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 liquid expands and the uranium
atom has become too dispersed to maintain fission so it starts cooling
down passively 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 of burden at Oakridge 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 transit Tomic we can make something that
works for five years that works for ten years like that we certainly know what
we're 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 10 years it's not going to be cheaper than coal and if
it's not cheaper than coal then it's not worth doing
the coal and all fossil fuels carry another cost to the environment in Japan
with the nukes mothballed they have kept the lights burning 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's 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
exponentially 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're going to
create a tremendous problem for future generations
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