This is going
to be a highly personal post, on a difficult (for me) issue, so I’ll kickstart
it by resorting to a cultural icon. You probably remember the segment in the first
movie of the Lord of the Rings trilogy,
right after Gandalf suggests to Elrond that may be the humans could reunite
under a legitimate king and be a force to be reckoned with against Mordor, when
Elrond cuts him short stating that “he was present when human strength failed”
(and since then, only three millennia in the past, he took humans to be a bunch
of good-for-nothing pansies, talk about having long memories of relatively
minor slights and grievances!)
Quick aside: one can only
wonder, knowing everything that came later, if the elven king’s wisdom did not
fail in a similarly epic scale that day, as all he had to do was kill Isildur,
take the ring from his corpse and cast it to the fires of mount doom, ending
the threat of Sauron there and then… of course he didn’t (he would have
pre-emptied not just the following two films of LoTR, but the three of The Hobbit as well, but let’s not get
too metanarrative here), and maybe the self-reproach for such misjudgment was
(repressed, and thus causing some overcompensation) somewhat behind his
cavalierly dismissal of another race’s capabilities.
But now, back
to my confession, I hereby declare, in front of the whole community of the Interwebz,
that I was similarly “there” the day, a bit more than five years ago, when the
strength of nuclear engineering was tested and was found wanting.
I distinctly
remember the 11th of march, 2011. Late afternoon that day I was
talking with the president of my company when we were interrupted by one of our
directors, who acts as our liaison with the CSN (Consejo de Seguridad Nuclear, Spain’s regulatory body regarding
nuclear energy), to tell us that Japan had been hit by a 9.0 magnitude
earthquake (the most powerful ever recorded there, and the 10th most
powerful on Earth since we keep records) and some of their nuclear reactors had
to be stopped. One location in particular, Fukushima, was close to the
epicenter and in the coast, but the first information we received was that it
had resisted the quake (a significant feat, as it was well above the “design
reference”, which means the plant had been designed to sustain a significantly
less powerful shaking… but the safety coefficients engineers always apply
seemed to have been enough this time) and was in a “hot stop” (subcritical,
controlled state). Our first reaction was of relief (just sustaining such
quake, again, is an impressive engineering feat –attested by the destruction of
many buildings in the same event, in one of the most seismically prepared
countries of the world), but we knew that the most severe test was yet to come,
as after such a violent quake near the coast a huge tidal wave (a Tsunami) was to be expected. Our
president ordered all our nuclear experts to be available on call 24 hours a
day for the following weeks, and to transmit the CSN that whatever support they
may offer Japan’s regulators and TEPCO (the operator of the plant) would be
fully backed by us.
That was not
an empty offer, as our company houses a significant amount of engineers with
deep knowledge of the BWR reactors manufactured by GE like the ones used in
Fukushima, because they have worked in the construction and operation of a
Spanish plant with the same technology (Sta. María de Garoña) and furthermore because
they have been involved with GE in the development of the next generation of
the same technology (the ESBWR). We soon learned that the tsunami protection
wall in Fukushima was a bit above 6 meters high, and that an earthquake of that
magnitude would produce a wave that would reach the coast up to 40 meters above
its usual level, so things didn’t look too brilliant.
The following
days would bring with them a rosary of bad news that confirmed our worst
expectations. The tsunami indeed passed easily over the wall, and washed
everything around the plant, including the tanks containing the fuel for the
emergency diesel motors that should keep the cooling water circulating and
preventing the fuel rods from melting. The wave didn’t affect the reactors
themselves, safely protected by an almost impregnable contention building. But
remember those reactors had been safely stopped (by the forceful injection of
control rods made of boron between the fuel rods, a procedure called SCRAM that
depletes the reactor core of the neutrons with the energy to keep the fission
chain reaction going) so the plant was producing no energy, and had to rely on
the external grid to power said cooling system. Unfortunately the external grid
had been similarly washed away, and it would take months to restore the main
lines. Not having the cooling system circulating the water around the fuel rods
is a very bad thing, as the long fission chains within the spent fuel produce
lots of heat, that in turn causes the rods to overheat, melt and produce while
melting significant amounts of a highly flammable gas (the zirconium alloy that
covers the fuel reacts with water to produce zirconium oxide and… hydrogen;
remember the tragedy of the Hindenburg? That’s a nice illustration of what the
combination of a high concentration of hydrogen and some heat can do).
So with all
that hydrogen concentrating freely within the reactor buildings (the operators
didn’t want to ventilate them, and thus lower the dangerous concentration,
because at that stage the hydrogen was full of suspended radioactive particles
in the form of aerosols, that would have been carried outside, and every nuclear
plant operator in the world has been trained to absolutely, by any means, come
what may, avoid letting any extra dose of radioactivity reach the public) it
was just a matter of time since a loose spark, or the simple contact with some
overheated surface, made all that hydrogen to explode in a stupendous
conflagration that blew up part of the contention building, effectively freeing
highly radioactive particles to be carried by the wind to the unsuspecting
public (well, not so unsuspecting, as the reluctant authorities were aware of
the dangers and had initiated the evacuation of the closest population).
The rest, as
they usually say, is history, but I want to dwell a bit more in the moment when
the main reactor was exposed (knowing that its integrity had been breached and
that part of the melting core was, for all practical purposes, burning at the
open air). We nuclear engineers pride ourselves of the soundness of our design
principles, and the robustness of the results we have reached with them. The
iconic accidents in nuclear power history have been either inconsequential for
the public (Three Mile Island) or due to a mixture of bad design and foolish
operation (Chernobil) that we disregarded as an aberration and a clear
violation of our code of practice. Between those principles two occupy pride of
place: defense in depth (having multiple layers of protection –the fuel rod
cladding, the reactor vessel, the reactor building lining- to ensure no
radioactive particle can escape to the open atmosphere) and avoidance of any “single
point of failure” (identifying any event that may cause such uncontrolled
release of radioactive particles to the atmosphere, and making that event not
just unlikely, but ludicrously so, by adding redundancies and safeguards that
prevent it from ever happening or, if happening, causing the adverse effects).
The image that we had all been trained to prevent, the state of the world we
explicitly tried to avoid, the stuff our nightmares are made of is precisely
what I remember distinctly seeing in Fukushima then: an exposed core of burnt
fuel (the most poisonous product of our trade), polluting the environment with
its deadly fumes for days (and then weeks) until it could be brought under
control again (it is questionable to what extent it is controlled even as of
today, as the “lava-like fuel containing material”, LFCM, also known as corium,
probably has melted not only the vessel but most likely the concrete slab under
it, and only God knows what depth under the plant’s soil it may have reached,
making the management of the underwater currents used to cool it pretty complex).
I guess like an urbanist confronted with Mexico DF Shantytowns, like a
Keynesian economist confronted with the ECB monetary policy, like a
neurosurgeon confronted with a XIX century lobotomy, I felt like what I held
more dear had been spoiled horribly and laid in its rotten state to die in
front of all the world who could only contemplate aghast such ugly agony and
pontificate how such a monstrosity could have come to be, and what to do to
ensure it never again happened (without much in the way of understanding).
What, indeed,
to do? Some normally sensible commentators (I remember Anne Applebaum in the
WaPo, but there were many more) advocated for the wholesale rejection of
nuclear energy. If the methodical and meticulous and careful and attentive
Japanese could not be trusted to operate their reactors safely, who could? It makes you shudder to think there are nuclear
power stations in Mexico (Laguna Verde), Brazil (Angra dos Reis), Argentina
(Atucha)… I don’t like to resort to stereotypes, and you can find everywhere (including,
of course, the three mentioned before as negative examples) extraordinary
professionals that can successfully compare with the best of the world, but let
us say the regulatory environment, the independence of the people tasked with
the verification of the compliance with such regulations and the average safety
standards I’ve seen widely extended and tolerated in such societies (I’ve lived
in the three countries) do not help to assuage my concerns about the risks that
such complex installations may end up causing in their laxly regulated
communities. But what is the alternative, then? For most of the years that such
plants have been operating the only real possibility for producing the amounts
of energy demanded by their economies (that aspired to grow as much, if not
more, than anybody else’s) would have required burning vast amounts of fossil
fuels, as wind and solar where costly toys with an extravagant price tag, and
hydro was already being used to the hilt (and had its own environmental
problems). Even today, when the price of (especially) solar has decreased very
substantially, given the problems associated with its intermittence and lack of
scalable means of storage in the right price bracket it is not feasible to just
shut them down and hope the economy will keep on chugging along (economies, in
most cases, heavily dependent on the export sector in cutthroat competition
markets, which can not afford the luxury of seeing their energy costs go up a
20-30% as the Germans did after cavalierly closing eight of their seventeen
nuclear plants –you know, the risk of a Tsunami going from the Baltic coast to
Neckar-Westheim or Biblis, only more than 500 km inland in a seismically stable
location, was just too big). But that was the old me thinking, the one that
still believed that all our efforts could be enough, that the risks were indeed
as low as our calculations showed them to be.
However, the
new me, the one that had seen the concatenation of unlikely events unfold (and,
a posteriori, reveal themselves to be
not only not that unlikely to begin with, but all too predictable) to finally
result in the unthinkable turning into the unavoidable, was not so sure. If
there is an existential risk to sizable chunks of the population, no economic
gain can justify subjecting those chunks to it. Of course, the lessons of
Fukushima were learned, and promptly applied. Our older 2nd
generation reactors (designed in the 50’s, let’s not forget!) have been made
safer, with diesel fuel deposits moved to higher locations, non subject to
flooding; new fast coupling connections have been installed so the
safety-critical systems can be fed with batteries even in the (now even more
unlikely) event of lack of fuel, and adequate arrays of batteries have been
safely stocked; new contention filtered ventilation systems are still being
installed, that would allow to reduce a potentially dangerous build up in
pressure within contention by relieving that pressure through HEPA filters
(that would retain the radioactive particles, avoiding dumping them in the
atmosphere), thus making a succession of events like the one that ended in the
explosions (and breach of all the defense barriers) all but impossible. Of
course, with all those design modifications, imposed by the regulators in all
the countries where BWR reactors still function, the price tag of nuclear
energy has kept creeping up (for critical minds, skyrocketing offers a better
description of the phenomenon than the milder “creeping up”), which makes the
whole proposition even more dubious (no kidding the British are having second thoughts
about Hinkley Point and their other chosen locations).
I really don’t
know, and part of the purpose of this long confessional was to clarify my own
position (something I’m afraid I’ve failed miserably at). I still tend towards
seeing a strong role for conventional (i.e. fission) nuclear energy in humanity’s
energy mix. As a species we need to master not only “environmentally friendly”
sources (solar, wind, hydro, tides, geothermal, although much could be said
about how environmentally friendly some of them really are, and how their true
costs keep being whitewashed by the media and the clueless “ecological”
movements that tirelessly promote them), but some “dense”, “hot” and yes,
potentially dirty, sources as well. As only half-jokingly I once said to a
friend, our descendants, sooner or later, will leave this lump of rock and
claim their place between the stars. And sure as hell it is not going to be
solar and wind which propel them there. Who knows, may be they even find some
other civilization in their never ending quest (which is the natural
continuation of our own never ending quest, btw), and when that happens, I hope
it is our descendants the ones that can deploy the hottest, densest (and yes
again, probably dirtier) energy to stand their ground. I just think we have to
be more humble about it, and to better understand the very real, very valid
concerns of those that don’t have such lofty aspirations for humanity. And keep
working hard, each one of us in the station he has been assigned (or the one he
has chosen), to assuage those concerns and make sure, as much as it is within
our reach, that the particular type of energy we have devoted so much of our
professional lives to further is indeed as safe and as clean as our equations
and our models purport it to be.
As a side note, I think our
collective failure to achieve perfect safety (even in the face of one of the
most destructive earthquakes history has ever recorded) in spite of the
enormous amounts of effort devoted to it (in terms both of time of very
skilled, very competent, and very expensively trained professionals, and of material
safeguards that also come at considerable expense) also has something to teach
us about why technology seems to have stagnated. We are so conscious of the
risks, we understand so deeply everything that can go wrong, we have developed
such comprehensive models, that allow us to forecast in such minute detail everything
that can happen in response to the most minimal perturbation that we literally
drown in documentation, become victims of the dreaded “paralysis by analysis”
and lose sight of the forest for the trees. And in the end I’m not even sure we
don’t end up missing the real risks (in this case, a much higher tsunami than what
we had prepared for) being lulled in a false security by all the too-distant,
highly unlikely ones that we have identified and mitigated…
But pursuing that line of thought
(the negative impact of over regulation and a culture of quality “assurance”
that puts impossibly high burdens in the development of any true innovation)
would take us too far from the modest goals I had set to myself in this
confessional, and would thus need to wait for a separate post.
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