[HN Gopher] Small nuclear reactors: tiny NuScale reactor gets sa...
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Small nuclear reactors: tiny NuScale reactor gets safety approval
Author : natcombs
Score : 324 points
Date : 2020-09-02 22:18 UTC (1 days ago)
(HTM) web link (www.popularmechanics.com)
(TXT) w3m dump (www.popularmechanics.com)
| nsxwolf wrote:
| Article gave absolutely no indication of its dimensions. How
| "tiny" is it exactly?
| adrianmonk wrote:
| Maybe tiny refers to the power output. The article says it
| makes 50 megawatts.
|
| Compare that to a nuclear plant near me which has two reactors
| that each generate 1280 megawatts.
|
| So it would take about 25 of these to equal the power output of
| a traditional nuclear reactor.
| petre wrote:
| Yes but it's inherently safer. Utility scale nuclear was
| scaled up from naval reactors which are smaller, use highly
| enriched uranium as opposed to LEU and are safer. Alvin
| Weinberg, the father of several LWR designs cautioned about
| the safety of utility scale reactors (17:51):
|
| https://youtu.be/EviEN0ScOwg
|
| The NuScale design also uses LEU and a plant is comprised of
| up to 12 of these modules sitting in water pools. You can
| view it as a battery pack where batteris are continously
| rotated as they are refuelled.
| jabl wrote:
| To nitpick, some naval reactors are designed to use LEU.
| E.g. French submarines run on 7% enriched fuel. And
| reportedly Chinese subs also use LEU.
| kyrra wrote:
| > The reactor measures 65 feet tall x 9 feet in diameter. It
| sits within a containment vessel measuring 76 feet tall x 15
| feet in diameter.
|
| Per: https://www.nuscalepower.com/technology/technology-
| overview
| tehabe wrote:
| you forgot to mention that those 23 m high containment
| vessels are places in in a pool which of course have to be
| much bigger than that: "The reactor and containment vessel
| operate inside a water-filled pool that is built below
| grade."
|
| We'll see of this is in any way or form sustainable,
| especially since uranium is also a finite ressource.
| DuskStar wrote:
| There's ~4 _billion_ tons of uranium dissolved in seawater,
| too. Which is enough for a millenia or three - if we used
| it for all of our power needs.
| tehabe wrote:
| That is not really the point, it doesn't matter if there
| is 4 or 40 or 400 billion tons of uranium, the point is
| that it is finite. At some point, there is none, or
| better there is no more usable ressources available. This
| can be shifted with technology and better knowledge but
| it is still finite. And that is all the point I wanted to
| make.
| john-shaffer wrote:
| The sun also will burn out eventually, and every other
| star as well.
| SamBam wrote:
| How much energy would it take to extract one ton of
| uranium from the ocean?
| Symmetry wrote:
| Well, according to "Sustainable Energy Without the Hot
| Air"
|
| >Japanese researchers have found a technique for
| extracting uranium from seawater at a cost of $100-300
| per kilogram of uranium, in comparison with a current
| cost of about $20/kg for uranium from ore. Because
| uranium contains so much more energy per ton than
| traditional fuels, this 5-fold or 15-fold increase in the
| cost of uranium would have little effect on the cost of
| nuclear power: nuclear power's price is dominated by the
| cost of power-station construction and decommissioning,
| not by the cost of the fuel. Even a price of $300/kg
| would increase the cost of nuclear energy by only about
| 0.3 p per kWh. The expense of uranium extraction could be
| reduced by combining it with another use of seawater -
| for example, power-station cooling.
|
| https://www.withouthotair.com/c24/page_165.shtml
|
| https://www.withouthotair.com/c24/page_174.shtml
| Invictus0 wrote:
| This article estimates that the cost of seawater
| extraction would be roughly 10x the current market price,
| although not much word on the energy consumption.
|
| [0] https://sci-
| hub.tw/https://doi.org/10.1016/j.pnucene.2017.04...
| jabl wrote:
| Add in breeder reactors and reprocessing providing a
| factor of 200 improvement in fuel usage, and we have
| enough uranium for millions of years.
| deeeeeplearning wrote:
| >We'll see of this is in any way or form sustainable,
| especially since uranium is also a finite ressource.
|
| I believe at current consumption rates there is still
| several hundred years worth of uranium. Presumably Fusion
| will have been figured out by then or we've killed
| ourselves with a climate disaster or something worse.
| welfare wrote:
| Nope, at the current rate of consumption it will last
| 70-80 years:
|
| https://en.wikipedia.org/wiki/Peak_uranium#:~:text=Accord
| ing....
| deeeeeplearning wrote:
| First section your Article: "As of 2017, identified
| uranium reserves recoverable at US$130/kg were 6.14
| million tons (compared to 5.72 million tons in 2015). At
| the rate of consumption in 2017, these reserves are
| sufficient for slightly over 130 years of supply. The
| identified reserves as of 2017 recoverable at US$260/kg
| are 7.99 million tons (compared to 7.64 million tons in
| 2015).[9]"
|
| Doesn't seem clearcut
| petre wrote:
| I wouldn't worry too much about running out of nuclear
| fuel. There's also Pu used in MOX fuel, breeder reactors,
| nuclear fuel reprocessing.
| tlb wrote:
| Almost all predictions of running out of ores have been
| wrong. They're based on "proven reserves," but mining
| companies don't bother proving much beyond 50 years
| worth.
| sudosysgen wrote:
| No, these are the reserve that are available at a given
| price. It is very sensitive to technology. Moreover,
| price of uranium is a small part of the cost of a
| powerplant, so there is not as much price sensitivity.
| We're still good for around ~200 years.
|
| Also, fuel can be reprocessed, and we can use other
| things than Uranium
| nickik wrote:
| Its not tiny at all, these are gigantic 'modules'. Its only
| small in comparison to a normal PWR reactor.
| foxyv wrote:
| Just barely too big to go on a standard tractor trailer. But
| small enough to be portable by a oversize load tractor trailer.
| Kind of like the blades for very large wind turbines in west
| Texas.
| m463 wrote:
| went across the a few years back and saw a LOT of those on
| trucks on the interstate. Maybe not a lot, but you notice
| when a truck is carrying something several hundred feet long
| down the road.
| 7952 wrote:
| The weight (590 tonnes according to wiki) is likely to be an
| issue. You need specialist vehicles that connect to a
| waterway or railroad.
| marshray wrote:
| I think it's disingenuous to argue the economics of nuclear
| without mentioning:
|
| "DOE reported that it faced an estimated $494 billion in future
| environmental cleanup costs -- a liability that roughly tripled
| during the previous 20 years."
|
| https://www.gao.gov/assets/700/696956.pdf
| draugadrotten wrote:
| How much is the future environmental cleanup costs of coal and
| oil?
| xigency wrote:
| If you consider the climate, about 100 times that.
| vlovich123 wrote:
| Is there a paper on that? 40 trillion sounds like a lot and
| I'm curious how that number is generated.
| godelski wrote:
| I can't think of a specific paper/s off hand but having
| been at labs where they do climate modeling and going to
| every talk I could I've heard estimates of tens of
| trillions to hundreds. So the ballpark at least passes my
| sniff test, though I know that this isn't a hard source.
| It is also difficult to estimate the damages and costs of
| climate change which is part of why costs vary so widely.
| (e.g. do you include events like Katrina?)
| ogre_codes wrote:
| Million acre forest fires are expensive to deal with.
| Likewise, drought, relocating billions of people
| displaced by sea level increase. Might be an under-
| estimate.
| xigency wrote:
| If you could solve climate change for less than that, I
| think it would be splendid.
|
| To put that number in context, which is just an order of
| magnitude, it's $5,000 for every person on Earth, about
| 1.5x the current US national debt, and just under the
| combined market cap of NYSE+NASDAQ.
|
| As an existential problem for humanity that doesn't
| currently have a solution, I think that's a decent cost
| estimate.
| Retric wrote:
| Climate change his hardly an existential threat for
| humanity. We survived the last ice age with stone tools,
| this is a less severe change. Economic impacts from
| things like rising sea levels really depend on how much
| we spend on maintaining things as they currently are vs
| adapting to the new normal.
|
| Aka do you live below sea level, raise the city, or move
| somewhere else.
| https://en.wikipedia.org/wiki/Raising_of_Chicago
| regularfry wrote:
| There's a very real risk that climate change could knock
| us back globally to a pre-agricultural level. If that
| happens, there's almost certainly no coming back: the
| only way we know how to get to our current level of
| civilization is by extracting substantially all the
| easily-extractable energy from the Earth's crust. We only
| get to do that once. This, today, could well be as good
| as it ever gets, for the only tree of life that we know
| for sure exists in the universe.
| Retric wrote:
| Surface level coal deposits are available across much of
| the globe, but let's ignore that.
|
| Agriculture can go a long way with animals, wood, and
| stone. Extracting energy from wind and rivers is easily
| attainable from that basis. At which point we would have
| serious energy to work with. Hydro electric dams provide
| 6.1% of the total U.S. electricity. That is plenty of
| energy to kick start industrial manufacturing and get to
| wide spread solar power.
|
| The next civilization may be extracting most of it's
| materials from our cities, but that's an advantage if
| anything.
| manfredo wrote:
| The last ice age occurred gradually over the span of
| millennia. Anthropic climate change is occurring in an
| instant by comparison. Not to mention, humanity survived
| by mass migration, something that's a lot harder for
| integrated global economies to do. Few believe humanity
| is going to go extinct. But extinction of industrialized
| civilization is a more real concern. And the collapse of
| industrialized civilization will undoubtedly entail the
| death of over 90% of the human population.
| Retric wrote:
| An instant in geological time not a literal instant.
| Death of modern civilization is always a risk, but not
| directly from climate change.
|
| The global food surplus is projected to continue even in
| the worst case. Energy and raw material production is
| similarly not a major concern. People continue to live in
| Dubai which demonstrate how extreme local conditions can
| get without forcing exodus. Further, few places are
| expected to get even that bad.
|
| Yes, changes to weather patterns, sea levels, invasive
| species, even diseases are likely. But, collapse of
| civilization is only really a risk if WWIII kicks off.
| throwaways885 wrote:
| People fleeing the climate alone could collapse the
| global food chain. I personally thing we're a little too
| interconnected in the name of efficiency.
| karaterobot wrote:
| This is in no way to disagree with your overall point,
| but marine cloud brightening looks like it might be a
| fairly cost-effective solution to climate change. It's
| unproven, but not an insane gamble either, and it has
| little risk of second-order consequences if it doesn't
| work. All that at a cost of single-digit billions per
| year.
|
| https://en.wikipedia.org/wiki/Marine_cloud_brightening#Co
| sts
| Forbo wrote:
| It seems to me to make more sense combating the problem
| at the source. This just seems to add more complexity to
| the problem. Did anyone else think of Snowpiercer when
| they saw this?
| RhodesianHunter wrote:
| This is IMO a positive for nuclear, not a negative. You're
| forced to confront the cleanup as opposed to fossil fuels,
| where you just blow your waste out into the atmosphere and make
| it the commons' problem.
| marshray wrote:
| If only a method for permanent disposal of nuclear waste
| actually existed.
| X6S1x6Okd1st wrote:
| If only a method for permanent disposal of excess CO2 was
| viable.
| crusty wrote:
| I think the modern (3rd generation?) Reactors have been
| designed to use much more of the fuel, leaving considerably
| less as waste, and actually potentially using preciously
| used spent fuel as fuel, which of course would be cleanup.
| The problem is approval and building of anything new.
| dodobirdlord wrote:
| The world is filled with naturally occurring phenomena far
| more dangerous than a big pile of low-grade nuclear waste.
| The really dangerous stuff ceases to exist after a few
| decades of sitting in a cooling pond, and then what's left
| has such a long half life that it's not particularly
| threatening. Water is an incredible radiation dampener, and
| the ocean is already chock full of dissolved uranium. The
| only reason we don't just toss our low-grade fission waste
| into an oceanic trench somewhere is that it's valuable and
| wherever we put it we know we'll probably change our minds
| and want it back for reprocessing at some point.
| Klinky wrote:
| You're underplaying the danger and overplaying the value.
| Who exactly is investing in this "green gold"? If it's so
| valuable why does no one actually want it, and why is the
| DoE stuck with half a trillion liability?
| rstupek wrote:
| Isn't the "green gold" as you state it what the traveling
| wave reactor folks https://www.terrapower.com/our-
| work/traveling-wave-reactor-t... hoping to use to
| generate their power?
| briffle wrote:
| They are stuck with the liability, because President
| Carter Banned reprocessing of Uranium in 1977, and nobody
| has changed it. If we reprocessed Uranium, we would end
| up with much less low level waste, and some very, very
| small amounts of more radioactive materials (that can be
| burned in some other types of reactors)
| Aeolun wrote:
| SpaceX can launch it into space?
| 0-_-0 wrote:
| And if something goes wrong at launch spread it over a
| nice big area
| omginternets wrote:
| If only a method for permanent disposal of carbon dioxide
| emissions from gas plants actually existed.
| IncRnd wrote:
| Sigh... If only a method for converting carbon dioxide
| emissions into another gas actually existed in nature.
| omginternets wrote:
| Plant trees and burn coal? That's your plan?
| IncRnd wrote:
| Every time I read something like this, my hubris alarm
| goes off. We couldn't even get trans-fats right, so I
| don't see how we're going to cover all the contingencies
| for something like this.
| asdfman123 wrote:
| Lots of methods exist, but they're too expensive or don't
| scale well.
| BurningFrog wrote:
| Many such methods exist.
|
| There are no methods that have 100% answers for every "what
| if 5 things go wrong at once?" question.
|
| That's true for everything, but those questions only get
| asked for nuclear energy.
| acidburnNSA wrote:
| There are good permanent disposal methods available. The
| deep geologic repository under construction in Finland is
| probably the best example. More info here:
| https://whataboutthewaste.com
|
| People use "what about the waste" as a reason to not use
| nuclear. Yet, fossil and renewable biofuel waste is (as
| mentioned) just dumped into the biosphere where it ends and
| estimated 8 million lives early per year, according to the
| WHO.
|
| https://www.who.int/health-topics/air-pollution
| godelski wrote:
| Not to mention the waste associated with semi-conductors.
| Long term waste is not just a problem associated with
| nuclear. It is also worth mentioning that the major waste
| issues are associated with DoE weapon sites and not as
| much power sites.
|
| I would also encourage other's to click on acidburnNSA's
| profile as this is where their expertise lies and they
| have written extensively (with plenty of links) on the
| subject.[0]
|
| [0] https://whatisnuclear.com/waste.html
| e12e wrote:
| Unfortunately that doesn't quite solve the problem of
| getting waste from reactor to storage site.
| dodobirdlord wrote:
| It's not really much of a problem. You leave the waste in
| a cooling pond at the plant for a couple of decades while
| you wait for all the _really_ threatening stuff to decay,
| and then drive it where it needs to go in a truck. It's a
| bunch of big metal rods in canisters. It can't really
| "spill" and if it does you just pick it up and put it
| back in the truck. Uranium and plutonium are really not
| very threatening to human life.
| liability wrote:
| Besides the obvious NIMBY problems, are there any
| problems with sealed casks transported by train?
| cogman10 wrote:
| No. These things are tested to a VERY high standard.
|
| https://www.youtube.com/watch?v=1mHtOW-OBO4
| manfredo wrote:
| Getting the waste to a storage facility is very easy. You
| put it on a semi trailer and move it to the storage site:
| http://large.stanford.edu/courses/2015/ph241/avery-w2/ima
| ges...
|
| Nuclear waste is radioactive, but not so radioactive that
| it's unsafe to stand next to a container. Most waste is
| stored on site.
|
| It actually doesn't make sense to move nuclear waste to
| permanent storage because some reactor designs can use
| this waste as fuel.
| marshray wrote:
| That option doesn't exist in the US.
|
| We have no permanent disposal facilities, not even in the
| planning stage.
|
| https://www.gao.gov/key_issues/disposal_of_highlevel_nucl
| ear...
| trothamel wrote:
| https://www.wipp.energy.gov/ is one, though that's for
| government rather than commercial waste.
|
| It's a matter of political will at this point.
| ethbr0 wrote:
| The 2012 Blue Ribbon Commission on America's Nuclear
| Future report [1] literally said that:
|
| _" Ensuring access to dedicated funding - Current
| federal budget rules and laws make it impossible for the
| nuclear waste program to have assured access to the fees
| being collected from nuclear utilities and ratepayers to
| finance the commercial share of the waste program's
| expenses.
|
| We have recommended a partial remedy that should be
| implemented promptly by the Administration, working with
| the relevant congressional committees and the
| Congressional Budget Office. A long-term remedy requires
| legislation to provide access to the Nuclear Waste Fund
| and fees independent of the annual appropriations process
| but subject to rigorous independent financial and
| managerial oversight."_
|
| [1] https://web.archive.org/web/20120807061024/http://brc
| .gov/si...
| manfredo wrote:
| We do have a permanent disposal facility built, but
| congress chose to forbid its operation. This is a self
| inflicted problem: we don't have a permanent disposal
| facility because we refuse to use the permanent disposal
| facility we built.
|
| https://en.m.wikipedia.org/wiki/Yucca_Mountain_nuclear_wa
| ste...
| ethbr0 wrote:
| FYI, to the ready point, as Wikipedia notes: _" The DOE
| was to begin accepting spent fuel at the Yucca Mountain
| Repository by January 31, 1998 but did not do so because
| of a series of delays due to legal challenges, concerns
| over how to transport nuclear waste to the facility, and
| political pressures resulting in underfunding of the
| construction."_
|
| The anti-waste-disposal crowd in the environmental
| movement feels exceedingly disingenuous.
|
| The amount of goal post moving they've engaged in over
| the decades makes it clear that their actual goals are to
| prevent _any_ waste disposal site from being constructed,
| rather than specific, actionable complaints.
|
| Which is insane, from a net-benefit perspective, as the
| alternative is to leave nuclear waste dispersed around
| the country, closer to population centers.
| philwelch wrote:
| It does. The long-lived wastes can be recycled into fuel in
| breeder reactors.
| garmaine wrote:
| It does. It's called a breeder reactor.
| manigandham wrote:
| We could dump it into the ocean and not worry about it.
| There's so much cooling capacity and radiation shielding in
| the oceans alone that we'd never run out of space, so all
| of the current disposal strategies are way above and beyond
| what's needed. Containment is solved problem.
|
| It's important to note that other energy types also produce
| waste. For example, coal ash is incredibly toxic and hard
| to dispose of, and we create much more of it every year.
| gambiting wrote:
| Another option which is completely safe and permanent* is
| drilling a borehole few km down and dumping the waste
| there. It's not coming back no matter what. The research
| done into it shows that "only" 800 boreholes would be
| required to store literally all nuclear waste ever
| produced.
|
| https://en.wikipedia.org/wiki/Deep_borehole_disposal
|
| *to a point where it was actually brought up as a
| negative, because if we ever wanted to recycle that waste
| into something else, it's literally impossible this way.
| moneytide1 wrote:
| There's one in Finland:
|
| https://en.m.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel
| _re...
|
| They have thought thousands of years ahead and set up
| many different types of warning signs and symbols in case
| a future civilization discovers it.
| Krasnol wrote:
| And than there is Asse:
| https://en.wikipedia.org/wiki/Asse_II_mine
|
| You just don't know.
|
| The time frame is too long. It's too long for natural
| causes and far too long for human civilisation. The
| earlier we stop producing this crap, the better.
| gambiting wrote:
| I think the difference is that the one in Finland can
| still be entered like a normal tunnel. The deep borehole
| is literally just a vertical shaft that goes 5-6km down,
| you put the waste on the bottom and fill it back up. No
| geological process is bringing the waste back up in any
| conceivable timescale, and even if the entire
| civilization collapsed no primitive society can dig to
| 5km depth, so there's no need for much long lasting
| signage, no one is going to stumble upon it by accident.
| jaggirs wrote:
| No, they put zero warnings. Warnings only make it more
| likely that someone decides to start digging.
| barbecue_sauce wrote:
| Are you trying to piss off Namor?
| [deleted]
| rstupek wrote:
| Or use the waste (which is still highly energetic) in a
| traveling wave reactor a la terrapower?
| fsflover wrote:
| https://whatisnuclear.com/waste.html
| manfredo wrote:
| Is this the cleanup cost for civilian power generation? Or for
| military reactors and nuclear weapons, too? Because all the
| nuclear waste from civilian power generation occupies a volume
| the size of a football field in footprint and less than 10
| yards high. https://www.energy.gov/ne/articles/5-fast-facts-
| about-spent-...
| SamBam wrote:
| How many pecks is that?
| godelski wrote:
| My understanding is that these DoE sites are weapon sites, such
| as Hanford. These are a different ball game than power plants.
| They use different technologies and have different kinds of
| waste. Sure apples and oranges are both round fruits, but
| aren't one to one comparisons.
|
| List of sites https://www.dnfsb.gov/doe-sites
| marshray wrote:
| "In 2015, President Obama found that a separate repository
| for defense-related radioactive waste was required. DOE
| reported that defense waste is smaller in volume, less
| radioactive, and thermally cooler than commercial spent
| nuclear fuel, stating that a defense repository may be easier
| to develop."
|
| https://www.gao.gov/key_issues/disposal_of_highlevel_nuclear.
| ..
| godelski wrote:
| This doesn't really counter my argument. The key part is
| that it has different kinds of waste. There are more
| factors than the radioactivity. For example sites like
| Hanford have melted fuel, which might have inspired that
| green goo that people associate with nuclear waste, but a
| power plant only produces solid waste. Aerosols and liquids
| have vastly different storage requirements and added
| complexity requirements than storing the typical fuel
| pellets and solid matter from power generating reactors.
| manfredo wrote:
| But crucially, commercial spent nuclear fuel is in
| containers. Spent waste from weapons development was often
| just dumped in a pit and buried. Our priorities were very
| different in the 1940s and 50s. Seriously look at this
| picture [1]. That encapsulates the attitude towards nuclear
| safety during the early cold war. The soviets just dumped
| their waste into a lake [2]. Not to mention we detonated a
| thousand or so nuclear bombs, many of them above ground.
|
| 1. https://en.m.wikibooks.org/wiki/History_of_Nevada/Nevada
| _and...
|
| 2. https://en.m.wikipedia.org/wiki/Lake_Karachay
| dylan604 wrote:
| Isn't more of Apples to Macintoshes to Honey Crisp to Granny
| Smith? It's all nuclear waste, but just a different variety.
| njarboe wrote:
| Almost everything on Earth contains some potassium,
| uranium, or thorium and thus is radioactive. Its all
| nuclear waste (from many big, nuclear events in the
| cosmos), just different varieties
| godelski wrote:
| It isn't. Because we're talking about vastly different
| types of waste with vastly different toxicity and
| radioactivity. Power plants also don't produce liquid
| contaminants. This difference means not only quantity
| differences, but also vastly different methods for storage
| are required. Ability to contaminate the local environment
| is also vastly different. Please stop just guessing at what
| waste actually involves and read up on it before making
| such claims.
| Wohlf wrote:
| Ah yes, the perfect is the enemy of the good.
| nickik wrote:
| It disingenous of you to argue that all DoE cost from the last
| 60 years have any implication on a modern nuclear site build.
| When nuclear started they had no idea how to do things and had
| to do a lot of things very fast.
|
| The waste majority of those cost are not because of civilian
| nuclear reactor, but rather creation of nuclear weapons.
|
| Site cleanup cost are a factor, but not a huge one considering
| a site can be active for 60-100 years.
| marshray wrote:
| Perhaps you'd like to link to some figures for the cost of
| permanent disposal of commercial waste?
|
| Or were you just planning to let the grandkids deal with
| that?
| nickik wrote:
| All US reactors already pay a fee that takes care of waste.
| This fee accumulates in government accounts because
| government because political deadlock. Since start of
| operations tons and tons of money has been gathered threw
| this process. Its completely because of government failure
| that no progress have been made. The fee was designed to be
| enough to handle the waste and it would be.
| erentz wrote:
| Yes. It appears to very explicitly is about DOE sites,
| national labs with waste dating back to the Manhattan project
| and Cold War. This figure would seem to be better described
| as the clean up cost for our nuclear weapons programs with
| maybe a small side dish of reactor research in places like
| INL.
| marshray wrote:
| The defense waste is just a fraction of the total:
|
| "The U.S. commercial power industry alone has generated
| more waste (nuclear fuel that is "spent" and is no longer
| efficient at generating power) than any other country--
| nearly 80,000 metric tons. This spent nuclear fuel, which
| can pose serious risks to humans and the environment, is
| enough to fill a football field about 20 meters deep. The
| U.S. government's nuclear weapons program has generated
| spent nuclear fuel as well as high-level radioactive waste
| and accounts for most of the rest of the total at about
| 14,000 metric tons, according to the Department of Energy
| (DOE). For the most part, this waste is stored where it was
| generated--at 80 sites in 35 states. The amount of waste is
| expected to increase to about 140,000 metric tons over the
| next several decades. However, there is still no disposal
| site in the United States."
|
| https://www.gao.gov/key_issues/disposal_of_highlevel_nuclea
| r...
| erentz wrote:
| Ok now you're conflating two separate things. The link
| and original figure you shared was about DOE sites. From
| your link: "EM's mission is to complete the cleanup of
| nuclear waste at 16 DOE sites..." You suggested this was
| connected with commercial reactor waste, it wasn't about
| that.
|
| Commercial reactor waste is not anywhere near the same
| kind of beast. It's contained and easily disposed of when
| the US eventually embraces science again. Other countries
| don't have as much problem and are building deep geologic
| repositories. Canada even let local communities bid to
| take the waste.
|
| If your in the PNW take a visit to Hanford when you can.
| What they did on these DOE sites during the nuclear
| weapons programs is absurd to think about with what we
| know today. They just buried all kinds of random toxic
| stuff everywhere and didn't even keep records.
| nickik wrote:
| > a football field about 20 meters deep
|
| That's not actually a lot is it?
|
| Also, all commercial reactors already pay a fee for
| nuclear waste disposal. There is tons and tons of money
| available that has been stored for 50+ years.
|
| The problem is that the government is totally incompetent
| and instead of developing a solution the money
| accumulates and politicians are in deadlock.
|
| Both the solution for long term storage for the US has
| basically been known since the 50 (not Nevada) and the
| way to reduce the 'waste' has also been known since the
| 60s. That noting is actually done is not a technical
| issue.
|
| However, commercial 'waste' is actually valuable material
| that we can easily store for 100 of years without much
| trouble or cost, and its not very dangerous either. This
| 'waste' will actually serve as a fuel for future
| reactors. Even if you believe that the whole nuclear
| energy industry will totally collapse and go away. The
| fees collected would allow for the development of a waste
| destroying reactor.
| [deleted]
| normanmatrix wrote:
| I was thinking Nuclear would be the stable baseline for
| renewable. But this is not a sustainable option. We need to
| enforce hydrogen.
|
| Do not submit to the fallacy of nuclear waste disposal. First
| Elon needs to fix space travel and make transport into the sun
| feasible. And we will have iter by then.
| HideousKojima wrote:
| Why would you need to put it in the sun? That would be a huge
| waste of energy, just stick it in a stable graveyard orbit, or
| just get it fast enough to escape Earth's gravity
| riquito wrote:
| Hydrogen can be a practical fuel, but you need energy to
| extract it, which could very well be nuclear
| phs318u wrote:
| Or solar. Or wind. Or tidal. The beauty of hydrogen is its a
| great way of time-shifting intermittent energy on a large
| scale (assuming a large enough water supply) for later use.
| I'm talking primarily about electricity generation as opposed
| to fuel for vehicles.
| nuccy wrote:
| Hydrogen is not a good (at the moment at least) source of
| energy or fuel for cars or industry (chemically speaking,
| obviously much better together with Deuterium and Tritium for
| fission, though we are still from such a technology). Steam
| reforming, which is currently the most common way of hydrogen
| production, uses natural gas and water and produces plenty of
| CO2 [1]. Nice summary as for cars fuel application here [2].
|
| [1] https://en.m.wikipedia.org/wiki/Hydrogen_production
|
| [2] https://m.youtube.com/watch?v=f7MzFfuNOtY
| nickik wrote:
| As a huge fan of nuclear power, I never felt like NuScale style
| 'SMR' were all that great of an idea.
|
| Yes, it gains you some of the economics of factory construction
| and that you can start small and scale a location, but on the
| other side you lose that again because you lose the economics of
| scale that traditional PWR gets.
|
| I really believe we should be a nuclear society by now, and that
| regulations both around reactors and fuel availability prevented
| this from happening. In the 1960 lots and lots of innovative
| reactors were build, often with relatively low budgets at that.
| The amount of untapped potential in nuclear energy is incredible.
| We don't need fusion, fission is plenty energy dense, if we can't
| figure out how to make fission practical, we want with fusion
| either.
|
| Yet here we are in the year 2020 and we are still building new
| PWR reactors. But the reality is, in the US it is essentially
| impossible to build anything else. Regulations are designed so
| that the only reactor that can really get approval is a PWR.
|
| If you attempt to build anything new, you have to basically pay
| the government to study your design and after a unknown amount of
| time and money, the government might develop a new regulatory
| framework. By the time that happens of course you have run out of
| money already, no buissness plan that depends on the government
| figuring out how to regulate a new type of reactor would ever
| really happen.
|
| The good thing at least is that the DoE in the last 5 years seem
| to have realized that their whole approach was a problem and they
| have done a lot of good things to try to change. Outside of the
| US the energy sector is government controlled or to small for a
| nuclear reactor startup to have a large enough market to make a
| new reactor worth it.
|
| Canada has established itself as basically the only viable place
| for new reactor development, with Terrestrial Energy and Moltex
| Energy (moved from Britain to Canada because regulation).
|
| So, good luck to NuScale, I hope they can prove me wrong and
| deploy many of these in an economical way.
| rubber_duck wrote:
| >Yes, it gains you some of the economics of factory
| construction and that you can start small and scale a location,
| but on the other side you lose that again because you lose the
| economics of scale that traditional PWR gets.
|
| You mean they lose operational efficiency ? Economies of scale
| come from the ability to mass produce.
|
| You forgot to mention the largest differentiator - eliminates
| the possibility of a global catastrophe.
| jabl wrote:
| > You mean they lose operational efficiency ?
|
| Historically, one of the few successful ways to lower the
| price per generated power from a nuclear power plant has been
| to make the reactor larger. So yeah, there's a reason why the
| latest traditional PWR designs such as the French EPR are
| huge (1600 MWe).
|
| The gamble with these small reactors like Nuscale is that
| series production of the reactors in a factory would make up
| for the loss of the traditional economy of scale due to size.
| It remains to be seen how well that will work out.
| evilos wrote:
| If you can pump out standardized large scale reactors like
| France did, then they are way more efficient than these
| smaller reactors.
|
| The problem of course is that takes a large government to
| mandate a huge public project, which is not really likely
| these days. The advantage of these small reactors for now is
| that they hopefully prevent expensive,bloated, one-off site
| designs that go over budget and miss their schedules.
| nickik wrote:
| Economics of scale are the reasons modern Gen3+ reactors are
| so huge.
|
| From AP1000 wikipedia:
|
| > The design traces its history to the System 80 design,
| which was produced in various locations around the world.
| Further development of the System 80 initially led to the
| AP600 concept, with a smaller 600 to 700 MWe output, but this
| saw limited interest. In order to compete with other designs
| that were scaling up in size in order to improve capital
| costs, the design re-emerged as the AP1000 and found a number
| of design wins at this larger size.
|
| So modern PWR are usually build with 1GWe one location one
| reactor, huge economics of scale in terms of the size of the
| power plant. A AP1000 is not much bigger then an AP600.
|
| > You forgot to mention the largest differentiator -
| eliminates the possibility of a global catastrophe.
|
| I disagree. First of all, I think the possibility of a global
| catastrophe with a traditional PWR are already incredibly
| small, and when talking a modern build like an AP1000 the
| NuScale doesn't have that much better safety characteristics.
|
| PWR are inherently problematic and require tons and tons of
| complex engineering to make them save and the error potential
| in such a solution are always there.
| acidburnNSA wrote:
| Not in nuclear they haven't historically. Economies of scale
| drove light water reactor designs from tens of megawatts to
| hundreds to over a thousand universally from all vendors
| around the world historically. The big institutional nuclear
| economics reports all agree that going big improves nuclear
| economics. The hypothesis that SMRs will somehow overpower
| this is popular but is very much unproven. This agrees with
| OECD reports like last month's [1] and all the older ones
| listed in [2].
|
| [1] http://www.oecd-nea.org/ndd/pubs/2020/7530-reducing-cost-
| nuc...
|
| [2] https://whatisnuclear.com/economics.html#improving-
| modern-nu...
| ed25519FUUU wrote:
| > _The current design, which still has several steps until it can
| be constructed in the wild, is for 50 megawatts per module.
| NuScale seeks to apply for a 60-megawatt version next._
|
| I'm very impressed by that output. It will make a difference with
| areas of high solar and wind generation, which can't maintain a
| sustained high duty cycle.
|
| I expect these types of reactors to be in places to _augment_
| solar and wind, not replace it.
| fareesh wrote:
| If you build one of these things don't you also need to build an
| impervious shell around them so they can't be attacked? I have
| read that the existing reactors can withstand air crash impacts,
| etc.
| Animats wrote:
| Four links down: _" The staff has determined that the plant
| design meets the applicable requirements for the design
| certification stage of licensing. ... The NRC staff's issuance of
| this FSER does not constitute a commitment to issue the design
| certification"_[1] The actual review document is not up yet;
| search for "ML20023A318".
|
| It's not that this is smaller. It's comparable to Shippingport or
| Vallecitos. The argument is that it's safe enough against
| meltdowns not to need a full containment vessel, which makes it
| cheaper. The idea is to have a group of these sharing the same
| reactor pool. What they do if there's a leak into the cooling
| pool. Does that take down all the reactors?
|
| Anyway, the plan is to build the first one at the Idaho Reactor
| Test Station, 830 square miles with reactors spread miles apart.
| If something bad happens there, it's not a major problem.
|
| [1] https://www.nrc.gov/docs/ML2023/ML20231A804.pdf
| linuxlizard wrote:
| > If something bad happens there, it's not a major problem.
|
| Well, unless you're in Idaho like some of us. ;-)
| jdeibele wrote:
| One thing not addressed is physical security. As pointed out by
| @adrianmonk it would take many of these tiny reactors to generate
| the same amount as a typical older reactor.
|
| Older reactors are designed like fortresses, supposedly able to
| take a direct hit by a commercial jet and survive. They have
| armed guards, etc.
|
| It would be interesting to see how they would try to protect
| these. Typical electrical substations are protected by a chain-
| link fence and a padlock.
| jabl wrote:
| The idea is to put multiple reactors at the same site, not to
| spread out mini reactors all over the landscape.
|
| So the end result would be a powerplant that produces about as
| much power as a "normal" nuclear power plant, just that it
| contains many small reactors instead of a few big ones.
| jessaustin wrote:
| This undermines some of the claimed benefits. A bunch of
| little Fukushima Daiichi reactors in the same location
| wouldn't have fared any better than the actual Fukushima
| Daiichi reactor.
| garmaine wrote:
| Uh, there are a bunch of reactors at Fukushima. It's in the
| name: "daiichi" means "complex-1", there is also a "daini",
| etc.
| jabl wrote:
| In this particular case, a power plant with these nuscale
| reactors would probably have survived a Fukushima type
| accident. One effect of being small is that the reactors
| are designed to be passively cooled after shutdown, using
| convection instead of pumped flow. So there is no need for
| emergency diesel generators to keep the coolant pumps
| running.
| hinkley wrote:
| What's the radius around a reactor where a critical core
| can trigger fission in the next reactor over?
| jabl wrote:
| You'd have to place both cores within the same reactor
| pressure vessel, which isn't possible.
| jessaustin wrote:
| Sure, it's safer for reactors to tolerate flooding, if
| indeed these reactors actually do tolerate flooding.
| Definitely that would be a better design in
| flood/tsunami-prone areas. No design (from history,
| _especially_ no reactor design) is perfect. A set of
| smaller reactors that were _not_ co-located would be more
| tolerant of site-specific vulnerabilities in their
| design.
| MurMan wrote:
| > ... if indeed these reactors actually do tolerate
| flooding
|
| The reactor modules are partially immersed in a pond, the
| ultimate heat sink. Cooling is passive, i.e., no cooling
| pumps, and does not require electrical power.
| hinkley wrote:
| I think you're screwed either way.
|
| The odds that a concentrated site has an event are much
| higher with colocation. But the changes of having an
| event at multiple locations are higher if they're spread
| out.
|
| Some things that I believe would matter for colocation
| would be:
|
| - chance of cascading failures
|
| - economies of scale/safety in numbers (1 large team vs
| many small)
|
| - plant-to-home efficiency (n fewer reactors due to
| smaller transmission losses)
| dangjc wrote:
| How is nuclear compatible with variable renewable energy sources?
| It can't ramp up or down quickly, so it's not good for filling
| the gaps in the day when the sun is not shining. And solar is now
| so cheap during sunny days that the excess power is curtailed or
| at a negative price.
| enaaem wrote:
| Nuclear can operate in load following mode for a long time now.
| It's already done in Europe.
|
| https://www.oecd-nea.org/nea-news/2011/29-2/nea-news-29-2-lo...
| RangerScience wrote:
| San Francisco in the summer :D
|
| I kid! AFAIK you most want this kind of immense baselines power
| for heavy industrial activities.
|
| Also AFAIK, if these are simple/easy/small enough, you could
| co-locate the heavy consumption with the generation which'd cut
| power consumption (due to transmission) by something like 30%
| (on top of infrastructure maintenance savings). Kinda like
| Netflix putting boxes in local switches (if I have those terms
| correct).
| cm2187 wrote:
| I don't understand what makes small reactors desirable. Don't you
| loose economies of scales, not only production, but also demand
| (ie if you have small local sources of electricity you miss the
| diversification of the demand you have in the central grid and
| you need to overprovision a lot more)?
| sarcasmatwork wrote:
| fyi, OSU college has a 1-megawatt research reactor.
|
| https://www.oregon.gov/energy/facilities-safety/facilities/P...
|
| https://www.corvallisadvocate.com/2012/got-nuke-state-of-the...
| whymsicalburito wrote:
| UC Irvine has one underneath the chemistry building
| https://faculty.sites.uci.edu/trigareactor/
| gresrun wrote:
| The University of Florida has a 100kW training reactor since
| 1959[0].
|
| [0] https://en.wikipedia.org/wiki/UF_Training_Reactor
| larrywright wrote:
| University of Illinois had one for many years in Urbana. My
| uncle ran the reactor and then babysat the fuel for a decade or
| so after it was decommissioned. It takes that long to get the
| fuel disposed of apparently.
| trimbo wrote:
| I just recently watched this video/tour of MIT's reactor,
| pretty interesting.
|
| https://www.youtube.com/watch?v=5QcN3KDexcU
| criddell wrote:
| McMaster University in Hamilton, ON has a reactor as well:
|
| https://nuclear.mcmaster.ca/facility/nuclear-reactor/
| jabl wrote:
| _A lot_ of universities around the world have research
| reactors.
|
| Back when I worked at my alma mater, I could see the reactor
| building across the yard from the coffee room. Still waiting
| for that third eye to start growing out of my forehead.
| nickik wrote:
| One of the problems in the US is that there are research
| reactors and production reactors, nothing in between. Research
| reactors are to small to prove out many concepts.
|
| So startups have to essentially go from nothing to first
| commercial reactor in one step, without iteration.
| adrianmonk wrote:
| The University of Texas at Austin has a 1-megawatt nuclear
| reactor:
|
| https://nuclear.engr.utexas.edu/netl/triga-reactor
|
| BUT... it also has two 74-megawatt gas turbines that supply the
| campus with electricity and steam:
|
| https://utilities.utexas.edu/chp/about-carl-j-eckhardt-combi...
| [deleted]
| jessaustin wrote:
| Mizzou has a 10MW:
|
| https://www.murr.missouri.edu/
| cronix wrote:
| Reed college in Portland has a 250kW one operating since 1968.
|
| https://reactor.reed.edu/about.html
| rtkwe wrote:
| North Carolina State University has a little 1 MW training
| reactor for it's Nuclear Engineering track.
|
| https://www.ne.ncsu.edu/nrp/about/pulstar-reactor/
| RangerScience wrote:
| Thinking about the cooling pool:
|
| Could you just make an off-shore in-ocean "farm" of these?
| AnimalMuppet wrote:
| Salt water might add to your corrosion issues. Also, physical
| security of nuclear reactors is a big deal. Now you need a navy
| to do it.
| RangerScience wrote:
| Half-kidding, and it wouldn't deal with the saltwater
| corrosion issues, but....
|
| Legit use for Project Plowshare harbors?
| AnimalMuppet wrote:
| And if you have a reactor leak, you just say it didn't
| matter, because Plowshare already contaminated everything.
|
| This is _insane_ , but it has a certain consistent logic to
| it...
| m3kw9 wrote:
| Things are always different when deployed, I want to see how it
| performs before real world before getting excited.
| kyle_morris_ wrote:
| NRC Release: https://www.nrc.gov/reading-rm/doc-
| collections/news/2020/20-...
| dang wrote:
| Also https://apnews.com/910766c07afd96fbe2bd875e16087464
|
| edit: and https://arstechnica.com/science/2020/09/first-
| modular-nuclea..., via
| https://news.ycombinator.com/item?id=24345288
| hinkley wrote:
| Can someone refresh my memory?
|
| Is generating electricity directly from the products of fission
| proven [mathematically] to be less efficient than
|
| decay->steam->mechanical->electrical
|
| or is just that the applied science of steam power is so far
| ahead of everything else?
|
| My peace of mind would be much greater if the energy transfer
| went through solid state systems instead of a working fluid that
| is pretty good at carrying the bad products of a [malfunctioning]
| reactor.
| kortilla wrote:
| Has there even been a case of the steam being problematic?
| cogman10 wrote:
| The problem is heat. fission produces a ton of it and it has to
| go somewhere. Yes, you can absorb radiation thrown off by
| fission, but you still have the problem that heat will melt
| everything.
|
| So you throw water (or salt) on the reactor, heat it up, and do
| work with the steam that is ultimately produced.
|
| It has less to do with steam being the ideal route and more to
| do the the practicality of dealing with heat.
|
| AFAIK, most reactors are closed loops anyways, so there's not
| much of an issue with water carrying away radioactive
| materials.
| jokit wrote:
| I was wondering if Hyperion Power Generation had become NuScale,
| but no.. apparently a different solution.
|
| I remember reading about Hyperions small plant that would be
| buried.
|
| Glad to see the progress. I wonder how Hyperion is doing.
| jhallenworld wrote:
| Here is the NRC website about this reactor:
|
| https://www.nrc.gov/reactors/new-reactors/smr/nuscale.html
|
| Here is an interesting sub-report:
|
| https://www.nrc.gov/docs/ML2022/ML20224A525.pdf
|
| Information withheld for security reasons. One item concerns the
| "ultimate heat sink". What happens when the ultimate heat sink is
| lost?
|
| Well a design assumption is that it is not lost:
|
| https://www.nrc.gov/docs/ML2020/ML20205L410.pdf
|
| "A key assumption of the PRA is the availability of the UHS to
| provide an adequate heat sink. To support passive heat removal
| with the DHRS or ECCS, the reactor modules are housed and
| partially submerged in the UHS such that most of the outer
| surface of the CNV directly contacts the UHS, which is a large
| pool of water in the reactor building (RXB). "
|
| DHRC is decay heat. CNV is reactor containment vessel. So drain
| the pool and the reactor is in trouble.
| wbl wrote:
| The pool is big. It is easy to fill holes in the ground with
| water. In some parts of the country very hard to keep them dry.
| adammunich wrote:
| It's really hard to comprehend just how much heat a reactor can
| make from decay alone. Like... boiling a hot tub in only a
| minute.
| jjoonathan wrote:
| Have people really found no way to dump it in an emergency
| with t^4 transfer?
| phkahler wrote:
| And so a pool of water is not enough because it will boil
| away. A continuous flow must be present that can not be
| interrupted.
| sesutton wrote:
| According one of their videos[1] by the time the water has
| boiled away the reactor will be cool enough that it can be
| air cooled.
|
| [1]https://www.youtube.com/watch?v=h--FAVoAQvk
| sitharus wrote:
| You need a sufficiently large reserve to allow the reactor
| to cool, not an infinite supply. Reactors can be shut down
| and in this case the pool is sized to absorb all decay heat
| from the shutdown, plus a significant safety margin.
| rkagerer wrote:
| And if the pool gets a leak?
| microcolonel wrote:
| Patch it? Keep adding water? There's lots you can do with
| a (non-catastrophic) leak, and building water vessels
| that don't leak in your lifetime is honestly not that
| hard.
| phkahler wrote:
| Great, and ideally gravity can be used to move it.
| Remember, at Fukushima power to the pumps was lost.
| tpxl wrote:
| Afaik some reactor designs drop the core in a tank below
| in case of emergency.
| asdfman123 wrote:
| The article states the whole reactor will be submerged in
| a pool of water, making it passively safe.
| meepmorp wrote:
| Reactor cores continue to produce waste heat when shut
| down, and water evaporates. It's passively safe till you
| run out of coolant, then it's actively dangerous.
| garmaine wrote:
| The reactor is submerged in the pool. It's a passive
| design.
| tgsovlerkhgsel wrote:
| Around 600-700 kWh per cubic meter depending on
| temperature. The reactor outputs around 200 MW thermal.
|
| So if you have one of them in an olympic size swimming pool
| 50x25x2 meters, 2500 m^3, it'd need ~8 hours to evaporate
| the whole pool at full output.
|
| If you assume decay heat as 1% of regular output
| (https://en.wikipedia.org/wiki/Decay_heat), you'd need to
| add (or have stored) ~3 m^3 of water per hour, or slightly
| less than a liter per second, to keep it from melting down.
|
| If you assume an average of 2% for the first two hours,
| that'd be 8 MWh -> 12-13 m^3 for the first two hours, so a
| 5x5x5 = 125 m^3 pool (only considering the part above the
| "must always stay submerged" level) should be able to cool
| it for days.
|
| I think _as long as the containment pool is intact_ (and
| you manage to SCRAM the reactor), this isn't going to be a
| major issue. But if e.g. an earthquake breaks the pool...
| birdyrooster wrote:
| >What happens when the ultimate heat sink is lost?
|
| The reactor ceases to transmit power and is shutdown for
| maintenance?
| natcombs wrote:
| >> What happens when the ultimate heat sink is lost?
|
| What's an example event where the ultimate heat sink might be
| lost?
| ColanR wrote:
| No expert, but if it's a pool of water then an earthquake
| might cause a leak?
| dylan604 wrote:
| evaporation?
| sandworm101 wrote:
| You don't need to be an expert. Ask anyone who has owned an
| in-ground pool. Leaks are rare but do happen.
| godelski wrote:
| Nuclear power plants were designed with this in mind. It
| would take a substantially larger earthquake to damage a
| nuclear power plant and cause it to leak than a
| commercial pool. Such a comparison is in bad faith and
| disingenuous.
| AnimalMuppet wrote:
| Cool it (pun intended) with the accusations of bad faith.
| Unless you have enough data to _prove_ it, don 't accuse
| it.
|
| "Substantially larger" is not the same as "impossible".
| And, given substantially larger consequences if a reactor
| pool breaks (compared to a swimming pool breaking), I
| don't think the question is out of line.
|
| We learned from Fukushima that natural disasters don't
| always follow the parameters that we expect them to.
| ses1984 wrote:
| It's a people problem.
|
| People are fallible on the best days, assuming everyone
| did their very best from nuclear physicists to
| construction workers, mistakes are made. You take steps
| to reduce the risk. Research gets review. Engineering
| schematics get review. Construction gets inspection.
| Still some mistakes will get through.
|
| And people always act their very best all the time right?
|
| You can even have a perfect design, perfect construction,
| that is mismanaged years after it's built, after the
| original engineers and bureaucrats lose control.
|
| The same people problems apply to basically every human
| endeavor, but nuclear's capability to cause accidents
| that have a lasting impact is pretty scary. You don't
| feel even a twinge of existential dread when you think
| about? If you don't, then I don't think I want you
| working on a reactor.
| markvdb wrote:
| This. Humans are spectacularly bad at this kind of scale
| in time/project budget/size...
| newacct583 wrote:
| Or an attack, of course. Or some other event (social
| unreset, invasion, coup, etc...) causes an evacuation of
| staff and it boils off during the resulting excursion.
|
| People tend to have poor mental models for the long tail of
| external failures that happen in real life. It's easy to
| imagine that things that have never happened in the last
| century would Never Happen. But... they will, somewhere.
| godelski wrote:
| Nuclear sites are designed to withstand a strike from a
| commercial airliner (747). Like you, the designers
| imagined many of the events you mentioned and more. A
| good rule of thumb is that if you, a non-expert, can
| think of a scenario within 10 minutes, an expert has
| probably already thought of this scenario. Nuclear power
| plants and weapons sites have always been considered
| targets and thus considered extra scrutiny in their
| design.
| thekyle wrote:
| Wow. How do they design them to withstand a strike from a
| 747? That seems really difficult.
| selectodude wrote:
| A whole lot of concrete, mostly.
| throwaway0a5e wrote:
| They shot an F4 target drone at a block of "reactor
| grade" concrete wall back in the 80s and they took
| measurements and did science on the resulting lack of
| damage and concluded that a reactor can shrug off one of
| anything. They didn't change containment buildings to be
| plane proof. It's just a side effect of the design
| required to contain a melting down reactor with a
| sufficient safety factor.
| shortandsweet wrote:
| You'd hope so. Reactors yes, but not spent fuel pools.
| Everyone misses things. I've found 3 design flaws myself
| in the industry. Not too big of a deal as actions can be
| taken to mitigate some of the flaws. The other flaws are
| less probable of causing an issue due to redundant and
| diverse systems but there's always the off chance...
| ktal wrote:
| https://interestingengineering.com/crashed-jet-nuclear-
| react...
| brandmeyer wrote:
| Many inland rectors are built on waterways. A plant can shut
| down due to drought. That's a slow enough process that you
| have plenty of advance warning, though.
| jhallenworld wrote:
| Some are built on man-made reservoirs held together with
| dams..
| kbenson wrote:
| Wasn't the big push (or maybe big PR push) for more research
| and development of Thorium reactors a few years ago because
| they fail closed/safely? That seems like the kind of thing
| you'd want for smaller reactors (which I assume means more and
| more geographically diverse, but don't really know).
| ses1984 wrote:
| There's no research being done on materials to safely contain
| molten radioactive salt, that research could be dangerous,
| pretty much only superpowers would have the resources to do
| the research.
| bbojan wrote:
| This was being done three years ago:
| https://www.powermag.com/thorium-molten-salt-reactor-
| experim...
|
| Also, I believe Copenhagen Atomics is doing this at the
| moment, but couldn't (quickly) find a reference.
| ansible wrote:
| Yes. Molten Salt Reactors (MSR), while operating very hot,
| are _not_ operating under a lot of pressure. A pressurized
| water reactor (PWR) _does_ , and if there is a leak or other
| problem, it can turn into an explosion.
| baron816 wrote:
| Have they announced an estimate of how much a reactor/cost of
| energy production will be? That's kind of the most important
| factor, isn't it?
| foxyv wrote:
| $0.24 per kwh is a rough estimate I've seen for NuScale.
| Typically initial costs for microreactors right now are around
| $0.25 to $0.30/kwh which is about the cost of energy created by
| diesel generators. Natural gas is much lower. However they hope
| that as we make a lot of them the cost will drop.
| mikeyouse wrote:
| Wow. That's substantially more expensive than I was
| expecting. It's been years but we always assumed ~$0.08/KWh
| for on-site natural gas generated electricity on US based
| projects.
| EricE wrote:
| This is huge. Not only are micro reactors far more economical, it
| dramatically reduces the need to maintain a massive nationwide
| grid and provides flexibility to people in remote areas including
| greater autonomy. Efficiency should be greater without massive
| transmission line losses. Might start fewer fires in California
| too.
| baybal2 wrote:
| > This is huge. Not only are micro reactors far more economical
|
| No, they aren't. They are more expensive per unit of power
| produced, by far bigger than any other powerplant in practical
| use.
|
| The only way I see nuclear getting economical is it getting
| _bigger_. Nuclear 's biggest advantage after the cost of fuel
| is its huuuuuuge power density, and power scalability. With
| currently technology level, it's possible to generate multiple
| gigawatts from a single reactor.
|
| > it dramatically reduces the need to maintain a massive
| nationwide grid
|
| It would not. Grid maintenance are quite non-linear, and high
| voltage lines are actually much cheaper per unit of electricity
| transferred than residential links.
|
| Very high voltage DC transfer is very economical, efficient
| enough for intercontinental connections, but very expensive.
| fuckyah wrote:
| What happens if this blows up? (Terrorist bombing, etc)
| 7952 wrote:
| I doubt it will reduce the need for a grid much. The most
| efficient way to deploy these is probably in clusters next to
| an existing big substation on an EHV line. The local
| substations are likely to be increasingly constrained by solar
| and wind that have to be distributed. Nuclear has no such
| requirement so why bother with hundreds of sites when you just
| need a few bigger ones?
| adrianmonk wrote:
| I'm not an expert, but I'm not convinced about it reducing the
| need to maintain a nationwide grid.
|
| Nuclear reactors take ages to ramp up and down. It's basically
| going to be generating the same amount of power 24x7, but
| demand is going to fluctuate. The more other areas you're
| connected to, the more opportunity there is to send that power
| to someone who can use it.
|
| Obviously there's a law of diminishing returns at some point,
| so maybe the grid doesn't need to be as large as possible.
|
| There are alternatives like energy storage (batteries, etc.),
| but you'd have to compare all the costs and benefits.
| m463 wrote:
| I can see that if these are distributed, the grid can be more
| of a mesh than spokes on a wheel.
|
| solar can do the same sort of thing.
| deegles wrote:
| > Nuclear reactors take ages to ramp up and down.
|
| Run them at full blast and dump the extra energy into direct
| air carbon capture? Of course that would require building the
| CC plants but it could be planned for.
| liability wrote:
| > _Nuclear reactors take ages to ramp up and down._
|
| Naval reactors are apparently very fast in this regard, so
| it's evidently not an _inherent_ property of nuclear power.
|
| (The USN also has an unparalleled record of safely operating
| reactors; more that 5,000 reactor-years clocked without major
| incident.)
| baybal2 wrote:
| > Naval reactors are apparently very fast in this regard,
| so it's evidently not an inherent property of nuclear
| power.
|
| Ramping up is easy, ramping down... not so much.
|
| It's not as much of an issue if you swim in your coolant,
| hence naval reactors are unique in being able to ramp both
| up, and _down_ quickly.
| trimbo wrote:
| Does it count that a Navy man was killed at SL-1?
|
| https://en.wikipedia.org/wiki/SL-1
| https://www.findagrave.com/memorial/67718734/richard-
| carlton...
| liability wrote:
| SL-1 was an Army reactor, so I would say it doesn't
| count. I'd also not count the USS Thresher or the USS
| Scorpion, since reactor accidents weren't the reason
| those sank.
| stickfigure wrote:
| Nukes are slow from a cold start but they can throttle up and
| down with load.
|
| https://en.wikipedia.org/wiki/Load_following_power_plant#Nuc.
| ..
|
| _Modern nuclear plants with light water reactors are
| designed to have maneuvering capabilities in the 30-100%
| range with 5% /minute slope._
| adrianmonk wrote:
| Wow, that's pretty fast. So 12 minutes worst case. TIL.
|
| Still, I wonder if the economics don't favor running near
| 100%. You've already paid the high up-front cost of the
| equipment, and fuel costs are low, so I assume you're
| better off selling excess power when possible.
| entropicdrifter wrote:
| I'd be willing to bet there are some significant thermal
| efficiency losses at 100% that would push you down closer
| to (made up number incoming) 80% at idle
| AnimalMuppet wrote:
| What's the maneuvering ability of a coal plant? I looked at
| the article, but didn't see it.
| toomuchtodo wrote:
| The economics are yet to be borne out. I believe the NuScale
| cost (feel free to correct me if this information is wrong) is
| still above the cost of renewables and storage [1] but below
| that of traditional PWRs (684Mw @ $3 billion [2], ~25 cents/kwh
| [3]), which is competitive in places like Hawaii (which is
| still relying heavily on diesel fuel for what solar isn't
| providing) and geographies with limited land or renewables
| potential, but not elsewhere (storage aside, you're still
| competing with renewables around 1-3 cents/kwh at utility
| scale).
|
| Congrats to NuScale for making it through to the other side of
| US nuclear regulatory purgatory. Optimism is warranted ("all of
| the above" to replace fossil fuels), but cautious optimism.
| It's not real until a commercial reactor is generating. Vogtle
| is still not done [4]. I hope I get to see a factory churning
| out prefab reactors ready for shipment.
|
| EDITs (to not pollute thread with replies): A carbon tax in the
| US is very unlikely, and you cannot count on economies of scale
| until you have arrived at scale.
|
| [1] https://www.lazard.com/perspective/lcoe2019
|
| [2] https://www.nuscalepower.com/benefits/cost-competitive
|
| [3] https://news.ycombinator.com/item?id=24346808
|
| [4] https://news.ycombinator.com/item?id=24061448
| donor20 wrote:
| I think it also depends on CO2 charges if any.
|
| For example, right now we have a pretty serious externality
| with CO2 for coal and other sources, what are the costs that
| folks would assign to CO2 to clear to needed target? That
| could bring comparative cost (with CO2 impact) down a bit.
| rubber_duck wrote:
| Thing is this kind of design benefits massively from
| economies of scale, same kind of thing that has drawn the
| price of PV down and other green energy.
| epistasis wrote:
| Up until recently the "economy of scale" meant massive
| reactors when it came to nuclear, and small modular
| reactors were abandoned because people didn't think they
| could be economical.
|
| We have radically different construction skill sets now
| than we did in the 1970s, so the economics may be different
| now, and it could have been that the planners were wrong
| before.
|
| But I'm any case, until a few of these have shipped, I'm
| not sure we'll know the true cost.
|
| These are manufactured like airplanes, a few at a time.
| Whereas solar has massive plants with hundreds of thousands
| of the same part assembled and shipped. I'm hopeful that
| they will provide another tool in the fight against climate
| change, but not super optimistic. There are many many
| technologies that are at a similar stage of development
| that could be used instead, such as cheap hydrogen
| electrolyzers, long-duration storage flow batteries, etc.
| And if these other techs succeed, they will also help SMR
| nuclear, assuming SMR nuclear can compete with renewables
| on cost!
| theptip wrote:
| Given the general cost disease affecting large
| construction projects, I think that massive reactors are
| an unviable proposition in western countries at this
| point. While the reactor core designs seem to be
| templatized, the projects to build them are not, and so
| there is huge inefficiency. E.g. see
| https://www.nytimes.com/2017/07/31/climate/nuclear-power-
| pro....
|
| If NuScale can build hundreds or thousands of these small
| reactors, they should be able to perfect a turnkey
| installation playbook that would hopefully reduce costs
| significantly, and perhaps more importantly, reduce
| variance on project spend/timelines. I think an
| unpredictable total cost of ownership is one of the
| things hurting nuclear projects.
|
| The big question in my mind is whether they can deploy
| enough of these to get to that scale, given that there's
| a fairly universal NIMBYism against nuclear power, even
| where this would be displacing CO2-emitting sources.
| marcosdumay wrote:
| > same kind of thing that has drawn the price of PV down
|
| A nuclear power generator is a complex beast, that requires
| a ton of material, of very different kinds, worked into
| some detailed and non-repetitive patterns. (Have you looked
| at a steam turbine?)
|
| PV is a simple pattern of a few different substances,
| repeated over and over again.
|
| Even if scale was all going into the PV price, nuclear will
| never be able to achieve the same amount of it.
| nickik wrote:
| This kind of design actually starts out with losing massive
| economics of scale of traditional PWR and hopes to get it
| back by economics of scale in manufacturing.
|
| I don't think NuScale will have much trouble competing with
| traditional PWR, but if they can compete in the overall
| market is a huge question.
| EGreg wrote:
| What's keeping the nuclear fusion so long? It's much safer.
|
| Can we use Thorium for now?
| engineer_22 wrote:
| Is Bill Gates an investor in NuScale? Or am I thinking of another
| modular reactor startup in the PNW?
| ascales wrote:
| Bill Gates is involved with TerraPower, the other PNW based
| nuclear startup
| engineer_22 wrote:
| Thank you
| mimixco wrote:
| "Officially safe" is a hilarious term which tries to predict the
| possibility of an MCA or "Maximum Credible Accident." Of course,
| Three Mile Island, Chernobyl, and Fukushima were also "officially
| safe" when they were built.
| jimiray wrote:
| I think picking a few accidents and saying that all nuclear is
| unsafe is such a disingenuous argument any more. All of those
| plants were based on extremely old designs and there have been
| tons of improvements. How about we focus on the "portable"
| nuclear power that is used by the US Navy for submarines and
| aircraft carriers safely.
| duxup wrote:
| This seems like fretting over a term.
|
| Everything is 'safe' until we discover it isn't and improve.
| Many things have improved over times. Calling them safe seems
| fine, we can do so understanding the process of learning and
| advancing.
| melling wrote:
| The passive safety is a big leap forward. Removing humans from
| that process makes it safer.
|
| "In the event of any runaway reactor event, NuScale says, the
| reactor quenches itself in its pool, making it "passively
| safe.""
| cma wrote:
| Any plausible scenarios where the pool leaks?
| core-questions wrote:
| What a bad faith post.
|
| > Three Mile Island
|
| Was handled reasonably well, resulted in safety improvements to
| procedures and designs for future reactors.
|
| From https://www.nrc.gov/reading-rm/doc-collections/fact-
| sheets/3...
|
| > The approximately 2 million people around TMI-2 during the
| accident are estimated to have received an average radiation
| dose of only about 1 millirem above the usual background dose.
| To put this into context, exposure from a chest X-ray is about
| 6 millirem and the area's natural radioactive background dose
| is about 100-125 millirem per year for the area. The accident's
| maximum dose to a person at the site boundary would have been
| less than 100 millirem above background.
|
| Not exactly the end of the world.
|
| > Chernobyl
|
| Accident caused by Communists who did not care about what
| happened to Ukrainians, as usual for them, and experimented
| with something that any nuclear physicist could have told them
| was a terrible idea. This is like blaming vehicles and calling
| them unsafe after reaching over from the passenger seat and
| yanking the wheel to drive a truck into a crowd. The moral of
| the story here is to keep Communists away from anything
| important, which applies to farms, industrial sectors, food
| distribution, and really most things more complicated than a
| pitchfork or a torch.
|
| > Fukushima
|
| Was reasonably safe for its long life, but they cheaped out on
| the necessary wall and drainage functionality; should probably
| have been decomm'd and replaced before this happened.
|
| The problem in the nuclear industry is that anti-nuclear people
| like you form public opinion that causes it to be difficult for
| it to move forward. New plants based on newer designs are
| orders of magnitude safer - e.g. the CANDU Canadian reactor
| which is more fail-safe than most, and the push towards 4th
| generation reactors.
|
| Get out of the way and let the planet have a clean base load
| energy source, or be sitting here bitching about carbon
| footprints 50 years from now when it should be a solved problem
| already.
| MertsA wrote:
| >> Fukushima
|
| >Was reasonably safe for its long life, but they cheaped out
| on the necessary wall and drainage functionality
|
| They didn't "cheap out" on the seawall at Fukushima. You may
| be referring to how the plant design was sited closer to the
| ocean but the seawall was constructed to not be overtopped by
| the highest tsunami possible. At the time the plant was
| constructed the theory was that tsunamis were generated in
| part by underwater landslides and the topology of the
| surrounding ocean was taken into account to come up with the
| largest possible tsunami it would have to block. The science
| behind tsunami formation was flawed during construction and
| once that theory was later improved no one ever reconsidered
| the implications for the seawall design.
|
| I agree that public perception is the largest problem by far
| with nuclear energy but you're not helping your argument by
| brushing real problems under the rug like this.
| jhallenworld wrote:
| Inherent safety of CANDU:
|
| https://inis.iaea.org/collection/NCLCollectionStore/_Public/.
| ..
|
| But keep in mind that the NRX reactor it was based on had an
| accident:
|
| https://www.cns-snc.ca/media/history/nrx.html
|
| (famously, Jimmy Carter was part of the NRX clean-up crew).
| redis_mlc wrote:
| > What a bad faith post.
|
| Yeah, when humans can be trusted, nuclear will be 100% safe.
| Any day now!
| m0zg wrote:
| > Communists who did not care about what happened to
| Ukrainians
|
| They didn't really care what happened to _anybody_, not just
| Ukrainians. Ukrainians (as well as about 30% of Russians)
| just happened to live in that particular location. The plume
| made it all the way to the Nordics and Germany, and I, as a
| kid, had to take iodine tablets in Russia, even though
| officially everything was "under control" for a few days.
| Then the narrative shifted to showing the heroism of the
| "liquidators", never fully acknowledging how dangerous any of
| this really was.
| core-questions wrote:
| Good point, I agree entirely. It's clear that nuclear power
| needs to be under the control of responsible governments,
| built in safe locations (i.e. not on fault lines, not in
| tsunami zones), and needs solid maintenance budgets.
|
| All of these things are solvable problems, but if we don't
| solve them before all the current nuclear plant techs age
| out, we won't be able to apprentice people and keep the
| culture of solid maintenance alive. At that point, they
| really do become an albatross.
| jessaustin wrote:
| This was true in USA too. They took pretty good care of the
| scientists who knew enough to call out unsafe conditions,
| but laborers etc. at e.g. PGDP were regularly exposed to
| poisons and radiation. EEOICP was put together late enough
| that many of the affected workers had already died.
| phs318u wrote:
| Bad faith post? Call me when the Nuclear Industries Indemnity
| Act (which socialises all costs over $12.6B in case of an
| accident) is repealed.
|
| What happens if the passive cooling pool drains? Let me
| guess, "That will never happen!"
|
| https://en.m.wikipedia.org/wiki/Price-
| Anderson_Nuclear_Indus...
| isatty wrote:
| > Accident caused by Communists who did not care about what
| happened to Ukrainians
|
| There were many such RBMK reactors spread all over the Soviet
| world that had the same flaws . There are many problems with
| your summary so can I just recommend that you watch the HBO
| mini series "Chernobyl" instead? It's a great watch.
| read_if_gay_ wrote:
| That mini series is indeed a great watch but it's also not
| exactly factual.
| regularfry wrote:
| Are there inaccuracies around the portrayal of why and
| how the reactor failed?
| core-questions wrote:
| Flaws? The meltdown was caused by a deliberate action on
| behalf of people with control of the plant.
|
| I haven't watched Chernobyl because I prefer to not get my
| history from television shows with a narrative axe to
| grind.
| regularfry wrote:
| My understanding is that those actions were only capable
| of causing the problems they did because of specific
| design choices involved in the coolant and moderation
| systems. Is that wrong?
| zymhan wrote:
| Previous Discussion 2 days ago
|
| https://news.ycombinator.com/item?id=24345288
| dang wrote:
| Yikes - that is a classic example of a post that accumulated
| lots of upvotes but stayed underwater the whole time:
| http://hnrankings.info/24345288/. This is a known problem and
| it's on our list to fix.
|
| Since that story didn't get much attention (relative to the
| interest in it), we won't call the current thread a dupe.
| dang wrote:
| @natcombs would you mind emailing hn@ycombinator.com? I'd like to
| suggest something so we can send you repost invites in the
| future.
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