
U.S. Reviewing Proposed Design of Miniaturized Nuclear Power Plant - vezycash
http://www.npr.org/sections/thetwo-way/2017/01/13/509673094/miniaturized-nuclear-power-plant-u-s-reviewing-proposed-design
======
Animats
There are lots of small and medium sized reactor schemes.[1] As of 2014, there
were four from the US alone, and 36 worldwide. Nuscale is covered starting at
page 80 of that study.

NuScale wants to operate their reactor modules in a water pool, with all the
reactors at a site sharing the same pool. If anything goes seriously wrong
with one unit, the pool gets contaminated. Then all the units, and the spent
fuel pool, are inaccessible, and repair becomes a huge problem.

The only reason NuScale is supposed to be cheaper is optimistic safety
assumptions. "The NuScale Emergency Planning Zone (EPZ) is expected to be as
near as the site boundary rather than the current 10 miles required by large
traditional plants in the U.S." \- IAEA. NuScale's design focuses on emergency
core cooling, with their water pool approach. But other things can go wrong.
Such as leaks. There's a long history of nuclear reactor leaks.

[1]
[https://www.iaea.org/NuclearPower/Downloadable/SMR/files/IAE...](https://www.iaea.org/NuclearPower/Downloadable/SMR/files/IAEA_SMR_Booklet_2014.pdf)

~~~
sandworm101
Installing partitions in the pool to isolate each reactor should be a very
minor expense. They need not even be self-supporting, just watertight enough
to prevent mixing.

Builing a larger or more partitioned pool shouldnt even enter into the cost
equation imho. Water and concrete are rather cheap given the context.

~~~
marze
Why have a common pool in the first place? To save the cost of individual
pools? That can't be much compared to the overall costs.

More likely you share a common cooling system between reactors. And maybe
containment?

~~~
sandworm101
I think that nuscale approach means there is no cooling system. The reactors
are small enough for the pool to passively cool them if so needed.

------
privong
It sounds like a neat idea, and potentially safer(?). But I don't understand
why they're claiming it'll be cheaper:

> But one company thinks that by going smaller, they could actually make
> nuclear power more affordable.

And later in the article:

> The company believes that 570-MW project can be completed for less than $3
> billion. By comparison, a new 1,150-MW reactor at Watts Bar in Tennessee
> cost around $4.7 billion and began operation in 2016 after years of delays.

Based on those numbers, the construction cost of the modular reactor system is
almost 30% more expensive per MW. Are they anticipating the operational costs
to be lower, thus saving money in the long run? But the article claims they're
trying to save on the construction costs:

> Companies such as NuScale hope to offset the higher costs by saving on the
> cost of construction

Which isn't true, based on the numbers the article quotes.

On a related note, I wonder if refueling these modular would be more
difficult/costly because of their smaller size and the submersion design?

~~~
maxerickson
The savings would likely kick in as they manufactured more and more of the
vessels.

~~~
privong
> The savings would likely kick in as they manufactured more and more of the
> vessels.

Maybe, but I would have thought that would have either factored that into the
quoted cost estimates, or that they would have said something like "and
similar future plants would cost X". (where X is lower).

~~~
Bluestrike2
Those cost savings won't be immediate, and will likely have to wait until
production facilities are expanded once there are sufficient orders to warrant
it. And not just immediate orders, but ones for a few years out as well.

~~~
privong
Sure, but surely they can make some sort of estimates, depending on
quantities, typical economies of scale, etc. Of course, I don't know accurate
they'd be in the end, but it shows they've thought about it in more detail
than "oh yeah, it'll totally be cheaper later on."

------
obelix150
This was described in depth in a recent Nova program called "The Nuclear
Option"[1][2]. In it they referenced multiple other more safe methods than the
most common type of reactors in use today which use technology designed
decades ago. Sodium based reactors were new to me entirely and appear much
more safe than existing designs, also capable of using depleted uranium.

Note: I'm not a nuke supporter just a curious guy.

[1]: [http://www.pbs.org/wgbh/nova/tech/the-nuclear-
option.html](http://www.pbs.org/wgbh/nova/tech/the-nuclear-option.html) [2]:
[http://www.pbs.org/video/2365930275/](http://www.pbs.org/video/2365930275/)

~~~
acidburnNSA
I watched it too and can elaborate a bit on this since I'm in the SFR business
(anyone want one?).

When an nucleus fissions, not all the heat comes out at once. Roughly 7% of
the energy comes out later, distributed in time as a decaying exponential [1].
The really key safety challenge of nuclear is cooling that after the chain
reaction is stopped (because 7% of 3 billion Watts is 210,000,000 Watts). So
if the power goes out (like in Fukushima), traditional plants rely on active
cooling systems like diesel generators, fuel cells, steam turbines, etc. to
run pumps that cool the fuel, preventing the fission products from emerging.

There are some nuclear reactors that can handle the decay heat without active
cooling systems. They're mostly low-pressure/exotic coolant systems, including
liquid sodium metal, molten salt (FLiBe, NaCl, etc.), molten lead, etc. These
can just naturally circulate and dump heat thorough ambient heat exchangers
outside. And some gas-cooled Pebble Bed reactors can do it too because their
fuel can get hot enough to just conduct it out.

Worldwide, we have by far the most experience with sodium-cooled fast reactors
(400 reactor-years). As pointed out in NOVA, two weeks before Chernobyl, the
small sodium-cooled EBR-II in Idaho demonstrated station blackout conditions
without scram and it just shut itself down and cooled itself.

But sodium metal has a problem. It is quite reactive with air and water, so
dealing with it can be an operational challenge. We know how to deal with
sodium leaks in sodium-water steam generators (arguably the most "exciting"
component in a SFR) and sodium fires, but they can still be expensive. The
French SuperPhenix SFR suffered a series of political and weather-related
challenges that ended up giving it a terrible operational record. The Japanese
SFR Monju has a bad history too with some 10 year outages and whatnot. But
EBR-II and FFTF in the US operated fantastically until Bill Clinton finished
shutting down their funding following the long slowdown of nuclear research
that came after the failed and super-expensive Clinch River Breeder Reactor
Project, and the Russians now have the best and only commercial SFRs.

So there's still hope for SFRs as Gen IV nukes. The French are working on a
huge program called ASTRID to make a better SFR. The Koreans have
KALIMER/PGSFR that's very far along in design. The US has TerraPower's
Traveling Wave SFR, the Indians are turning a big one on now, China is
operating a sodium-cooled test reactor (CEFR). The Russians are building
another awesome SFR test reactor (MBIR, to replace BOR-60) and continue to
operate and sell their BN-600/800, etc. series power plants.

[1]
[https://whatisnuclear.com/physics/decay_heat.html](https://whatisnuclear.com/physics/decay_heat.html)

~~~
WhitneyLand
Great post, now let's cut to the chase: Would you buy a house a raise a family
across the street from a 3 billion watt reactor?

~~~
XorNot
Yes. (1) because you ask that question, it means land is going to be cheap.
(2) my lifetime radiation dose will be lower then if I live anywhere near a
coal plant. (3) my respiratory health will be a lot better then if I live
anywhere near a coal train line.

(4) you could also argue I'm just saying this because asked - but I live in
Sydney with a primary science degree. One of the places I really wanted to
work was the Lucas Heights Research Reactor.

~~~
tajen
I'm sorry that I'm off-topic, but let's have a cultural minute here: while
you're there, I've never succeded to locate the industries when I lived in
Sydney. Does Australia get much of its energy from nuclear? Where are the
plants located in NSW? Do you also have some petroleum industries like
refineries? I've never seen refinery-type landscape (kilometers of stack
chimneys). Do you have industrial landscapes in Australia, like we have in
Europe with kilometers of factories, low-income workers, areas which are
monitored for huge industrial risks? My question is as much about the
geography of NSW as about the industrial sector of Australia.

~~~
XorNot
Australia get's literally none of it's energy from nuclear - the Lucas
Height's reactor is a research reactor (60% enriched uranium core) which
manufactures medical isotopes for our part of Asia and supports research.

We have some of everything, but I can't think of anywhere where I'd say we
have long industrial landscapes. NSW is quite agrarian, a fair bit of high
tech industry, but you can still live in towns which run near coal transport
lines (2um particulates are a big health concern for residents from the dust).
I live in Sydney near the center, so it's pretty much all commerce.

------
mmaunder
Nuclear reactors have been used on submarines for decades. McMurdo base in
Antarctica was powered by a nuclear reactor for 10 years which ended in the
70s.

~~~
tyingq
For comparison, the reactor described here outputs 50 megawatts, and is 15
feet in diameter and 76 feet long (~54,000 cubic feet).

The S6G reactor in Los Angeles class submarines outputs 150 megawatts and is
33 feet in diameter and 42 feet long (~144,000 cubic feet).

~~~
ci5er
I'm getting bleary eyed from a day that has gone on too long, but how does
something approximately 33x33x42 feet equal 140k ft^3? Same question with the
first one too. The cubic-feet measurement is including something else, right?
What might that be?

~~~
tyingq
Oops...thanks for the catch. Used diameter instead of radius when calculating
the volume of each cylindrical object. So, the cubic footage is off...but for
both.

So, corrected:

For comparison, the reactor described here outputs 50 megawatts, and is 15
feet in diameter and 76 feet long (~13,500 cubic feet).

The S6G reactor in Los Angeles class submarines outputs 150 megawatts and is
33 feet in diameter and 42 feet long (~35,000 cubic feet).

~~~
ci5er
Yeah -- I figured that out after I caught a little shut-eye. If my brain had
been operating at all, I would have seen that and not even asked. Sorry.

------
microDude
I have seen this company slowly mature over my past 6 years living in
Corvallis, Oregon (original location for NuScale). I was excited when I first
saw the design and started to look at employment opportunities at the company.
At the time, they only were looking for experienced engineers (15+ years) with
knowledge of the Nuclear Regulation Commission (NRC).

Even after 6 years, they just now have submitted the application to NRC. It is
depressing how much Nuclear has been over-regulated.

~~~
azinman2
What makes you think it's more than necessary given the consequences?

~~~
striking
I think it might be easier to answer that question if you outline which
consequences you're most concerned about.

~~~
beders
A single accident can kill thousands, cause cancer for several hundred
thousands more, cost billions of dollars in clean up usually tax payers pay
for, nuclear plants have no concept of proper disposing and dismantling a
reactor, have byproducts with unacceptable half lives, are potential targets
for terror threats, use other harmful chemicals (people like to ignore) etc.
etc. etc.

~~~
Natsu
Chernobyl-style reactors are a thing of the past, modern ones don't do all
that.

Even Fukushima didn't kill anyone, just some contamination that will cause
some statistical level of cancer increase.

------
tyingq
Not sure if I've got apples to apples here, but...

This thing fits on the back of a semi truck, and is supposed to be 50
megawatts capable.

The Hooper solar power plant in Colorado's San Luis valley is also 50
megawatt, and spans 320 acres.

Edit: Well, apples to apples for actual "energy density" vs photo voltaic
cells. Not making a statement about which is better either...just an
interesting comparison.

~~~
jessriedel
Nuclear power plants have very large "clearing areas" for safety and security
reasons. In fact, one of the reasons Elon Musks cites for investing in solar
rather than nuclear power is that the power area density is actually
comparable. Here's some criticism of that claim, but it agrees that it's
within about an order of magnitude (which is impressive given that nuclear is
probably dozens of orders of magnitude denser in power at the scale of the
reactor).

[https://carboncounter.wordpress.com/2015/07/13/a-book-
recomm...](https://carboncounter.wordpress.com/2015/07/13/a-book-
recommendation-for-elon-musk/)

~~~
masklinn
tyingq lists Hooper at 50MW/320 acres, or 156kW/acre. The Paluel nuclear plant
is 5200MW (4x1300MWe reactors) over 400 acres ("160 hectares" according to
[https://www.edf.fr/groupe-edf/producteur-industriel/carte-
de...](https://www.edf.fr/groupe-edf/producteur-industriel/carte-des-
implantations/centrale-nucleaire-de-paluel/presentation)), or 1300kW/acre, so
it's within an order of magnitude yes.

As long as we only consider nameplate capacity and ignore capacity factor of
course, which greatly favours solar as it has a much lower capacity factor
than nuclear. If you factor that in the difference grows by ~4x (PV in dry
southern US states has a capacity factor of ~20%, US nuclear plants are around
90%).

------
throwaway7645
50 MW is small for all the red-tape necessary to operate a nuke plant. 1500 MW
is nice if you're going to need over 1,000 staff. I'm not sure how much
headcount they could eliminate with a better design.

~~~
ethbro
I'm assuming the plan is that a 15x50MW install isn't going to use 15x the
1x50 personnel and site prep. Otherwise there'd be no way they're viable
except for smaller requirement installs.

------
pfarnsworth
Are thorium plants not viable? I remember hearing so much about them, but
nothing ever happened, it seems.

~~~
blisterpeanuts
The Wikipedia article[1] on thorium reactors lists the following disadvantages
(quoted from the article):

\- Breeding in a thermal neutron spectrum is slow and requires extensive
reprocessing. The feasibility of reprocessing is still open.

\- Significant and expensive testing, analysis and licensing work is first
required, requiring business and government support. According to a 2012
report by the Bulletin of the Atomic Scientists, about using thorium fuel with
existing water-cooled reactors, it would "require too great an investment and
provide no clear payoff," noting that "from the utilities’ point of view, the
only legitimate driver capable of motivating pursuit of thorium is economics."

\- There is a higher cost of fuel fabrication and reprocessing than in plants
using traditional solid fuel rods.

\- Thorium, when being irradiated for use in reactors, will make uranium-232,
which is very dangerous due to the gamma rays it emits. This irradiation
process may be altered slightly by removing protactinium-233. The irradiation
would then make uranium-233 in lieu of uranium-232, which can be used in
nuclear weapons to make thorium into a dual purpose fuel.

/end quote

I do wonder whether some of these issues are significantly different from the
problems of uranium fission reactors. The benefits of thorium are huge: can't
be used to produce nuclear bomb material; easier to prevent meltdowns;
enrichment of fuel not needed.

[1] [https://en.wikipedia.org/wiki/Thorium-
based_nuclear_power#Po...](https://en.wikipedia.org/wiki/Thorium-
based_nuclear_power#Possible_disadvantages)

------
Gargoyle
How does this compare to what the Y Combinator backed UPower is doing?

~~~
acidburnNSA
I believe UPower reactors (no renamed to Oklo after the spontaneous chain
reactions that occurred in Africa 2 billion years ago) are even smaller. My
guess from the rename is that they want to make shippable modules that are
entirely self-contained, i.e. you just set it down and plug stuff in. Could be
useful in very distributed markets. NuScale can ship lots of parts but you
still have to build out a big site.

------
ChuckMcM
_" NuScale is already partnering with a consortium of Utah utilities to build
a 12-module power plant on land in Idaho owned by the U.S. Department of
Energy."_ \-- I wonder if they would run all the wires over the border to a
giant data center right there on some DoD owned land. :-) [1]

The TRIGA reactors are similar [2] although much smaller. I'm surprised they
would share a pool though I'd think having them in separate pools would
provide both better encapsulation if something was to go wrong and easier
maintenance and disposal.

[1] Actually the NSA's data center is south of the Great Salt Lake so it would
be a fairly long run of wires for that.

[2] [http://www.ga.com/triga](http://www.ga.com/triga)

------
WhitneyLand
When you spend 5 Billion on a reactor how does the cost break down?

R&D, construction, permitting and regulatory?

It's hard to understand why it can't be done less expensively without big
safety compromises.

~~~
acidburnNSA
Depends on the reactor, but very roughly:

$500M on R&D $3000M on construction $1500M on permitting and regulatory

Construction delays and supply chain issues have been known to bring
construction costs way up.

------
castratikron
I wonder how the energy density of one of these compares to a traditional
reactor. That's what I would intuitively correlate with safety. Solar and
wind, for example, are very safe mainly because they has such a low energy
density.

~~~
sandworm101
Safety is in the eye of the beholder. Turbines do fail, sometimes with fire
and explosions. When so spread outt, hundreds of turbines, forest fire is a
risk. A nuke plant, being smaller, can be better covered by safety systems
than an expansive wind farm. But the practical differences between the two
techs are so great that direct comparison is probably pointless imho.

------
ohnotthatguy
You all have heard that we can harness energy from the light of the sun and
convert it into electricity[1] with the risk of contaminating the environment
which sustains us[2] coming only from the production of the tools to harness
that energy from light, right?

Aside from the context of space travel beyond where collecting this
underutilized resource, "Light From Stars" is viable, why is this even a
conversation?

[1]
[https://en.wikipedia.org/wiki/Solar_power](https://en.wikipedia.org/wiki/Solar_power)

[2]
[https://en.wikipedia.org/wiki/Lists_of_nuclear_disasters_and...](https://en.wikipedia.org/wiki/Lists_of_nuclear_disasters_and_radioactive_incidents)

------
maverick_iceman
I'm pessimistic that this proposal will go very far in the face of sustained
opposition by groups like Greenpeace or Sierra Club. Another tragic remainder
of the harm caused by undereducated misdirected environmental activism.

------
beders
Why? This is pure lobbyism.

There is a cheaper, safer and abundant alternative. Solar energy. Just do it
already.

~~~
dmix
> McGough says the company envisions the modules also could be used in other
> ways. For example, he says, they could be installed near wind turbines as
> backup when the wind isn't blowing. Or they could be used by the military to
> power bases that need electricity even if the grid goes down. About a dozen
> clients in the U.S. and abroad are looking at the technology, he says.

~~~
beders
Renewables is the way to go. No waste problem, vastly reduced risk. Why bother
with this?

------
intrasight
With current and foreseeable low cost of natural gas in the USA, nuclear tech
will never be economically competitive. In addition, the nuclear industry asks
the government to legislate liability caps.

~~~
tmuir
Is the foreseeable future greater than 16 years? In 2001, the entire energy
sector looked unrecognizable when compared to 2017.

~~~
intrasight
Foreseeable until something changes.

Utility companies are making long-term capital expenditure bets in a uncertain
political and economic environment. If they can get cheap gas and cheap gas
turbines, why would they consider risky, expensive, unproven technologies?

------
beders
Stop looking at nuclear. (Maybe read up on the nuclear disasters so far and
think about that when they install a nuclear power plant in your
neighborhood...)

Also, again, why bother?

[https://www.greentechmedia.com/articles/read/how-much-
renewa...](https://www.greentechmedia.com/articles/read/how-much-renewable-
potential-does-the-u.s.-have)

Vote this down all you like, it doesn't change the facts.

~~~
acidburnNSA
Nuclear reactors are extremely safe and disasters are very unlikely. Obviously
Fukushima and Chernobyl come to mind but so do famous plane crashes. This
doesn't mean planes aren't incredibly safe. Net, nukes have saved 1.8 million
lives by displacing air pollution deaths.

Nuclear is very small footprint. There is 2 million times the energy in a
handful of nuclear fuel than in a handful of fossil fuel. If you got all of
your primary energy from nukes (electricity, heat, transportation) as an
average american for 80 years, you would require 1.5 soda cans of fuel and
generate 1.5 soda cans of waste.

Comparing that to fossil fuels is a non-argument, nuclear is a clear winner.
Comparing to renewables is less straightforward, but consider all the
manufacturing and process to build out the facilities to harvest all that
unbelievable magnitude of wind and solar. Magnets in turbines and
semiconductor additives in solar PV have to come from somewhere, and currently
scaling to world-scale is nearly infeasible. Once thin-film solar can be done
without rare-earths it might become doable, but will still have a huge huge
footprint. Now start asking about energy storage. Imagine a northeastern US
winter on one of those icy and cloudy cold nights. Now imagine that lasts a
week or two. The storage and/or long-distance transmission is unimaginable. In
these conditions, nuclear chugs along beautifully, 24 hours a day, rain or
shine.

In desert sun with no nearby cooling water, solar kicks ass whereas nuclear is
challenged.

Renewables and nuclear are both essential to responsibly power human
civilization.

~~~
sfifs
I think the problem is the historical fact that cost of negative externalities
of nuclear projects don't get built into these projects are borne by tax
payers and people with significantly disrupted lives in very short durations.
The two big meltdowns Fukushima and Chernobyl have left large areas
necessarily depopulated and certainly have raised cancer risks. No one seems
to have a realistic end of life plan for nuclear sites and the next generation
inherits the problem.

If we mandate nuclear plants buy enough insurance cover to deal with
Fukushima/ Chernobyl type disasters, they would likely be completely
uncompetitive with other power sources.

