The Rise of Small Nuclear Plants

ColdWetDog writes "The Oil Drum (one of the best sites to discuss the technical details of the Macondo Blowout) is typically focused on ramifications of petroleum use, and in particular the Peak Oil theory. They run short guest articles from time to time on various aspects of energy use and policies. Today they have an interesting article on small nuclear reactors with a refreshing amount of technical detail concerning their construction, use, and fueling. The author's major thesis: 'Pick up almost any book about nuclear energy and you will find that the prevailing wisdom is that nuclear plants must be very large in order to be competitive. This assumption is widely accepted, but, if its roots are understood, it can be effectively challenged. Recently, however, a growing body of plant designers, utility companies, government agencies, and financial players are recognizing that smaller plants can take advantage of greater opportunities to apply lessons learned, take advantage of the engineering and tooling savings possible with higher numbers of units, and better meet customer needs in terms of capacity additions and financing. The resulting systems are a welcome addition to the nuclear power plant menu, which has previously been limited to one size — extra large.'"

Comments

This is good.

[elucido]

Nuclear energy is probably the best chance we have are breaking our addiction to oil. Nuclear energy is also relatively clean. I don't know why the government doesn't just fund the development of a bunch of nuclear power plants and put them on the coast or on the ocean somewhere. We could generate enough power to power the entire country, not to mention we could probably put hundreds of thousands of nuclear power plants in the desert.

Re:This is good.

[h4rr4r]

Peak Uranium? So then we move to thorium, or get uranium out of the sea, or burn our spent fuel. This is a solvable issue.

Re:This is good.

[JackCroww]

I recently was part of a discussion about energy here in the US and this was my brother's contribution:

It's quite simple, actually. The United States has not built a nuclear power plant since the seventies. Almost all of the plants we built then, and all of the plants that are still online, are pressurized light water (PLW) designs. This means that that coolant in the reactor, which also moderates the nuclear reaction, is ordinary water under great pressure (typically at least twice the industrial norm of 600 lb/in^2 steam). A PLW reactor produces as much plutonium 239 as it consumes uranium 235. We erroneously call Pu-239 nuclear waste, and the governments since the Clinton Administration have been looking to find a place to bury it for a quarter of a million years.

However, until the Clinton administration, your government was busy designing a better reactor. The program was called integral fast reactor, or IFR. IFR was a metal-moderated reactor. The coolant was liquid metal, sodium or lead. These elements don't moderate the neutrons, they fly unhindered through the pile. That means they can fission Pu-239. In fact, they can fission anything higher than uranium on the periodic table. That's not all a fast reactor can do, though. It can also turn anything on the other (left) half of the bottom row of the periodic table into fissionable material. That's what "fast" means in the name. The reactor produces its own fuel from thorium or uranium in its natural state! Just the uranium that has been mined to date, which we use for cannon shells once we've taken the U-235 out of it, is sufficient for 300-400 years of the US energy needs. The known reserves are good for 50,000 years or so. Uranium is more plentiful in the earth's crust than gold or tin, and there is three times as much thorium as uranium. Energy forever.

What does "integral" mean? It means that the fuel is recycled on-site. The fuel in the IFR is in metallic, rather than ceramic form. It is simply re-smelted periodically (not the whole load, just a few rods' worth), and the slag is the only waste. The balance of the fuel plus a tiny bit of uranium or thorium in its natural state, is recast into pellets and returned to the reactor. The volume of the nuclear waste is reduced by several orders of magnitude. The nature of the waste is only the light elements that are the products of the fission reaction. They have either extremely short half lives, measured in seconds to months, or such long half lives that they are essentially stable. They are also mainly low-energy beta emitters, instead of neutron and gamma emitters. While this waste is hellishly radioactive at first, it will be less radioactive than uranium ore in less than 300 years, and reactors might produce a couple hundredweight in a fifty year lifespan, instead of thousands of tons of spent fuel rods as a PLW reactor would.

Additional benefits of the IFR design? The fuel is in metallic form, suspended in liquid metal. It gets no hotter than the coolant, and thus cannot have a catastrophic loss of coolant, or "blow down", which is what happens if there is a leak in the primary circuit of a LWR. The fuel in a LWR is in ceramic form, and gets much hotter than the coolant (which is in turn much hotter than liquid sodium). If it were not continuously cooled, it would destroy its container and melt, hence the term "melt down." If that happens to enough fuel elements in a reactor, the fuel gathers at the bottom of the vessel and continues to react, until it melts through the bottom of vessel, or the "china syndrome." None of these is possible with the IFR design. As it gets warmer, the fuel assemblies expand and move away from each other, slowing or stopping the reaction. The IFR, in fact, was tested for this. They turned off the control system. The reactor heated slightly, and stopped working. The cut off the heat exchanger (simulating what happens if the heat exchanger or a turbine goes bad at a LWR plant)--same thing. The reactor heated slightly and shut itself down,

Re:This is good.

[h4rr4r]

Clean coal cannot exist. What are you going to do with all the waste? What will you do with the CO2?

It is a freaking PR job by the dirtiest industry in the USA. They top off mountains and dump the remains into peoples drinking water. Then they store hazardous waste in open ponds and let that run onto people's property. These folks make the nuclear industry look like saints.

Re:This is good.

[JackCroww]

Your rebuttal is an ad hominem attack? Normally I'd ignore you, but instead, I'll let you try looking at the first bullet point under the "Global Significance" section: http://en.wikipedia.org/wiki/Integral_Fast_Reactor to see if you might change your mind. As for Libertarianism, do you have a better suggestion? At this point, almost anything has to be better than the two parties currently spending our children into oblivion: http://pajamasmedia.com/richardfernandez/files/2008/11/fed-rev-spend-2008-boc-s1-federal-spending-has-increased.gif

Re:This is good.

[Surt]

No one had the technology to kill everyone on earth until the mid 70s, so that was a pretty implausible claim for all but the last 40ish of those thousands of years.

Re:This is good.

[Urza9814]

Saying nuclear won't fulfill our needs because of "peak Uranium" is at best stupid, at worst a lie to try to stop development of nuclear power. We likely have enough fuel (Uranium, Thorium, Plutonium, etc) for _thousands of years_ at our current energy consumption. That's the electrical grid, cars, everything. If we can just make everything run on electricity and build the best reactors our scientists can design, we would be fine for hundreds of years at a _minimum_. And I think it's safe to assume we'd be switched over to fusion by then :)

The problem is not the technology, it's not the resources, it's the regulations and the industry. We aren't building new plants because power companies aren't willing to invest large sums of money. Because regulations make it hard for them to _acquire_ large amounts of money (limits on how much profit utilities can take in.) We can't build breeder reactors because, for an extremely short period of time, they produce enriched uranium. Without breeder reactors, we can't take care of the waste problem because it lasts freakin' forever (without breeder reactors) and nobody wants it stored or transported anywhere within a thousand miles of them.

If you got a bunch of engineers and said "figure out how to solve our energy problem", they could throw together a nuclear power system that could power the world into the next millennium - and it would be cheap, it would be clean, and it would be safe. It's only restrictions like "you can't create highly radioactive products, even for a few seconds, you can't build anything big, you can't build anywhere near populated areas, and you can't use the word 'radioactive' or 'nuclear'" that causes problems.

Re:This is good.

[Gizzmonic]

Fourth, and maybe most telling of all, is the Obama administration's recently proposal of $8 Billion in loan guarantees for the nuclear power industry. Translation -- nuclear power is such a bad investment that nobody wants to give them any money.

Of course it's 'bad investment' from the perspective of people looking to make money. Building infrastructure is always a 'bad investment.' Yet we all benefit from it. Nuclear power is still the safest and cleanest energy out there. Clean coal has been shown again and again to be a lie. Nuclear power is used in Japan and throughout Europe. Let's take the plunge!

Re:This is good.

[RsG]

Even if you use all our nukes someone will still make it.

Depends on how you use them.

If the cold war had gone hot, most of those nukes would have been aimed at targets in the northern hemisphere, with several warheads per target (as insurance, in case some didn't launch, didn't work, or got shot down). Contrary to popular belief, most of the targets were military, rather than civilian - cities were a low priority, missile silos were a high priority, for reasons that should be obvious. Post nuclear losses due to radiation poisoning, starvation and infrastructure collapse would probably have been higher than the actually death toll inflicted by the bombs, and as you correctly say, people would survive. Contrary to some predictions, nuclear winter would not have been likely, but we didn't know that at the time.

Now, if you actually wanted to achieve total human genocide using the worlds current nuclear arsenal, I'm not at all sure you couldn't. Don't bother with the cities, just hit all the arable land, and let starvation take its course. Of course that is a very morbid thing to consider, and is sufficiently horrible, not to mention suicidal, that we'd never actually do it, but you were discussing whether it was possible, rather than whether it was likely.

Re:This is good.

[hackus]

Part of this energy problem is socieconomic. Virtually no one is discussing the obvious problem of cenralizing power.

It is not going to work.

What should be happening is every home should have its own power system, and should be self sufficient, connected to a grid which can resell excess energy per household back to the grid for use.

The idea of central authorities controlling all the power of whole regions is economically as well as politically dangerous.

For example, lets talk about Obama's terrorist boogieman. What is easier to pick off, central power plants owned by a wealthy few? Or everyone's home self sufficient which provides its own energy with no one point to attack?

Our own socieconomic models are designed for the military industrial complex to provide a reason for its existence.

Technology could be developed to provide homes that generate all the energy they require, but it is being denied due to these and other facts which would destroy the wealthy's power structure so it cannot be permitted.

Combinations of natural gas turbines, solar power, gas, oil, solar and wind and geothermal, nuclear and space could easily be distributed by regions household based on what energy sources are cheapest or practical.

Change isn't hard. It is hard though when 14 families control all of the worlds energy supplies and do not look kindly upon ideas that threaten the status quo.

-Hack

Re:This is good.

[DerekLyons]

If you got a bunch of engineers and said "figure out how to solve our energy problem", they could throw together a nuclear power system that could power the world into the next millennium - and it would be cheap, it would be clean, and it would be safe.

ADM Rickover thinks differently:

• An academic reactor or reactor plant almost always has the following basic characteristics: (1) It is simple. (2) It is small. (3) It is cheap. (4) It is light. (5) It can be built very quickly. (6) It is very flexible in purpose. (7) Very little development will be required. It will use off-the-shelf components. (8) The reactor is in the study phase. It is not being built now.
   
• On the other hand a practical reactor can be distinguished by the following characteristics: (1) It is being built now. (2) It is behind schedule. (3) It requires an immense amount of development on apparently trivial items. (4) It is very expensive. (5) It takes a long time to build because of its engineering development problems. (6) It is large. (7) It is heavy. (8) It is complicated.
   

Re:This is good.

[cheesybagel]

Nuclear power is cheap and clean. It is cheap enough that France exports large amounts of electricity to Italy, Germany, and the UK. The importing countries closed or scaled down their nuclear power investments to placate local enviro-weenies but are OK importing it, even if the reactors are right next to the border. France has some of the cheapest electricity costs in Europe. So I do not get where you are coming from.

Check the DOE energy reports. In the US nuclear power generates more electricity than wind, solar, hydro and other renewables combined. If CO2 is considered a pollutant there is no clean coal.

Re:This is good.

[Firethorn]

I'd recommend looking at this post.

First, the nuclear power industry pretty much has the best safety record going. Per dollar of product produced, it kills the least amount of people. Let's see, in the past decade it's killed, what, 3 people (the 3 Japanese workers in a reprocessing plant that got stupid by using a steel bucket instead of the multi-million machine intended for the purpose). Just this year, in the USA, for oil and natural gas we have the Deepwater horizon, which killed 11. China regularly loses hundreds each year, we lost 25 in the explosion at Massey this year. 34 miners lost their lives the year before in various incidents.

Second - Let's look at Yankee Rowe - third commerical nuclear reactor. Shut down early due to concerns that the reactor vessel might be becoming brittle.
Cost: $36M in 1960, $209M in 2k dollars
Decommission: $450M($567M), worst case. $320M($403M) is the 'basis average'.
During it's life, Yankee Rowe produced 34 Billion kwh, achieving a sub-performing 74% capacity factor - most of the newer reactors still in service are well over 90%.
So, going by an average 3 cents a kwh, that's $1.02B in electricity produced. That leaves $244M for operations and profit during it's time. So not very expensive, though not as good as would be hoped. If you go by the worst case decommission costs. Basis average would be a lot better, as would it have been if the reactor had lasted it's expected lifetime.

Third - You have got to be kidding me. 19.4% in 2007

Fourth - So nuclear power needs loan guarantees to proceed. Wind and Solar power need cash subsidies, often in excess of half their cost! Heck, your 'clean coal' got more subsidies than nuclear - $29.81/MWh for 'clean coal', Solar $24.34 and wind around $23.37, nuclear got only $1.59/MWh

In total dollars:
Refined Coal: $2,156M
Solar: $14M
Wind: $724M
Nuclear: $1,267M

The biggest problem with coal is air pollution. There is technology available to reduce pollution to negligible levels, but nobody wants to use it because it's "too expensive". Instead of flushing a few Billion down the toilet with nuclear power, we could put that money into clean coal technology.

Still have the problems with fly ash and such, so it's still not 'clean', and at that point your 'clean coal' is more expensive to install than nuclear, as well as more expensive to operate.

Re:This is good.

[Anonymous Coward]

"The coolant was liquid metal, sodium or lead. These elements don't moderate the neutrons, they fly unhindered through the pile."

It's not all roses. For one thing these metallic coolants will all become highly radioactive themselves due to neutron activation, sodium is extremely chemically reactive (spontaneous ignition in air or H2 generation in water that then burns -- choosing non-reactive materials to go in the reactor primary coolant loop is a challenge too), and starting up/shutting down these things is tricky (solidified metal in the pipes is kind of inconvenient). Lead is trickier to work with because of its relatively high melting temperature. Lead-bismuth alloys with much lower melting temperatures are more typical, although unfortunately bismuth gets highly radioactive too.

The ability to use natural (i.e. non-isotopically enriched) uranium is not unique. The heavy-water-moderated CANDU reactors also have this ability. The main problem there is the cost of the heavy water.

IFR is an interesting reactor design but there are plenty of other options.

I also don't know why you consider the Clinton Administration the turning point for finding "a place to bury it for a quarter of a million years". That's been underway since 1982 at least (the Nuclear Waste Policy Act). Certainly there are options for using the "waste" as fuel rather than discarding it outright, but those options were discouraged by multiple administrations since the 1970s.

Re:This is good.

[zx-15]

Actually, it's even easier, add cobalt to several nukes on site, blow them up on site and let winds and currents take care of the rest. http://en.wikipedia.org/wiki/Cobalt_bomb

Re:This is good.

[MightyDrunken]

I'm not defending the GP's post but to describe nuclear power as cheap, at least historically, is not true.

The reason France's electricity is so cheap is because the government sets the price and has subsidised the cost. Recently EDF have been investigated for price fixing because of this.

The real reason why no nuclear power plants have been constructed for decades in many countries is mostly because gas and coal were cheaper. The fact that some considered it to be unsafe was a secondary issue. Now that gas prices are rising and there is growing concern about the environmental effects of coal, nuclear power starts looking competitive again.

The Navy?

[CohibaVancouver]

I would assume the nuclear plants found on submarines and large warships both provide a lot of energy and are not in the category of 'extra large.'

Re:The Navy?

[Chris Burke]

I would assume the nuclear plants found on submarines and large warships both provide a lot of energy and are not in the category of 'extra large.'

Nor are they in the category of "economical", which is what was meant by "the prevailing wisdom is that nuclear plants must be very large in order to be competitive." Economically competitive, you see. Something the Navy cares about far less than, well, basically every other factor that goes into the design of a naval nuclear power plant.

Re:The Navy?

[RsG]

To minimize sound possibly?

Not even a little. Nuke plants are noisy. This actually poses a problem aboard nuclear subs. Of course a carrier isn't stealthy to begin with, especially not if deployed in a battle group, so the reactor noise isn't relevant.

The GP asked why the navy would use a nuke if a gas turbine would do the job. Fuel is the biggest answer, as a nuclear reactor needs refueling infrequently, and removing the need for large fuel tanks leaves more room for other stuff - in the case of a carrier, the "other stuff" would include aviation fuel and munitions, two things needed in quantity. In the case of a sub, the reactor is desirable in that it lets you stay submerged more or less indefinitely, since you can electrolyze water for oxygen.

Other than those two situations (carriers and subs), naval nuclear reactors are uncommon for exactly the reason given at the beginning of the thread: cost.

Re:The Navy?

[RsG]

Sure, if you had some way of searching the ocean for faint traces of hydrogen bubbles, and if said bubbles co-operated by not reacting with anything in the meantime. So far as I know we've never developed anything like that. Now, to put on my paranoid hat for a second, "so far as I know" could just mean that attempts to do this were classified, though I think the easier explanation is that nobody has bothered.

I don't want to say it isn't possible, because that's the sort of sentiment that invites the universe to prove me wrong, but lets just say it's a needle in a haystack sort of problem. You'd be looking for faint chemical trace over a vast area, with the trace in question being chemically reactive enough to virtually guarantee it won't linger. At a minimum, your solution would need to be used over a narrow search region.

Now, look at the problem from the opposite direction. Stealth under water is relative. A submarine, however well designed, however well commanded, can be found using existing methods, provided you know roughly where to look for it. Think of how many shipwrecks have been found by searching the general area they sunk, often decades or more after the fact. Now, factor in that those wrecks are on the ocean floor, meaning it's harder to spot them on active sonar than a sub, that the wrecks are utterly silent instead of just mostly silent, and that many of those wrecks were found using non-military hardware (meaning a few boats with active sonar pinging the ocean floor, instead of a fleet of warships and air-dropped sonar buoys).

The key concept here is knowing where to look. If all you know is that a sub is somewhere in the Atlantic, then you aren't going to have much luck finding it. If you know where to look, you don't need anything like a hypothetical hydrogen searching method when more straightforward options exist.

Re:The Navy?

[RicktheBrick]

In 1974, I was a member of the commissioning crew of the USS Virgina (CGN-38). It was nuclear powered. They made several more of that class. When they needed to be refueled they were all decommissioned. So why did the Navy want to pay for the fuel for a conventional powered ship rather than paying the expense of refueling a nuclear powered ship? It is strange since when I retired from the Navy, every ship that I had been a member had already been mothballed even those ships that were built after I had first joined. The only nuclear powered ships today are aircraft carriers and submarines. Submarines are nuclear powered since they do not need oxygen to run. Conventional powered submarines need to surface to run their diesels to recharge their batteries and thus were exposed during that time. Aircraft carriers are large enough to save money over conventional power so unless the Navy goes back to nuclear powered ships, they belief in only big nuclear reactors. It would be nice if the Navy could build a ship with nothing but laser weapons powered by a nuclear reactor.

theres still problems

[mjwalshe]

as a small nuclear plant still needs almost as much safety, inspection infrastructure not forgetting the larger number of armed guards (the nuke police had guns way before they where that common in the rest of the uk) as a big one.

Re:theres still problems

[ATestR]

Not so much. Depending on the design, a nuclear reactor can be self regulating.

As far as producing small nuclear power plant, check out the ones soon to be marketed by Hyperion

.

Re:un-American

[MrEricSir]

Yes. That's why in my bathroom you have to climb up a ladder to get to the toilet seat, then hang on for dear life for fear of falling into the swimming-pool sized bowl.

It also has a bidet function, which isn't wimpy and French; it's got a firehose pump powered by a small nuclear plant.

Macondo blowout?

[Hatta]

Let's call it what it is. The BP disaster.

Re:put them all over as the power grid is not setu

[spazdor]

I can't imagine investing in a national nuclear infrastructure without also overhauling the distribution grid.

Re:Titles are useless

[h4rr4r]

Because there is hydrogen and carbon in space.

Peak oil is not about running out of oil, it is about running out of oil that is cheap and easy to get. Those hydrocarbons in space are too expensive to bother with, especially when we have all this uranium and thorium laying around.

Re:un-American

[Chris Burke]

It also has a bidet function, which isn't wimpy and French; it's got a firehose pump powered by a small nuclear plant.

Ya almost had me up to that point, ya cheese-eating pansy!

Re:Nuclear waste

[Nethemas the Great]

WRONG. The technology to reprocess nuclear fuel has existed for more than half a century and is currently employed the world over. Just not in the U.S. In fact breeder reactors incorporate reprocessing into the design to use a fraction of the fuel and produce a fraction of the waste of those reactor types permitted in the U.S.

The problem with nuclear waste is one of politics, not of technology. Following on the heels of Gerald Ford's ban of commercial plutonium reprocessing, Jimmy Carter signed an order to ban the reprocessing of spent commercial nuclear fuel. Regan overturned the ban in 1981 but there was no funding provided to start up reprocessing facilities nor has the DOE provided license for anyone to do it. While they've waffled a bit during the Bush-Obama presidencies the DOE presently doesn't want domestic reprocessing. This has accordingly put a rather big crimp in the success of the GNEP which had closed loop nuclear power as a primary goal.

Re:put them all over as the power grid is not setu

[toastar]

I can't imagine investing in a national nuclear infrastructure without also overhauling the distribution grid.

did no one RTFA?
Oh yeah this is slashdot.

The idea is as Coal Plants get decommissioned you can use most of the same equipment, Which I assume means the same generators. Which make the nuke plants cheaper then overhauling the coal plant.

Re:Waste of Uranium

[smellsofbikes]

the anti-nuclear crowd should be renamed the anti-braincell crowd

I get frustrated by statements like this.

I'm pro-nuclear: I took classes to become a nuclear power plant operator, once long ago, and if someone were willing to let me put a TRIGA-sized power-producing reactor in my back yard I'd jump at the chance if I got free power out of it.

With that said: most of the people who oppose nuclear power aren't stupid. They just have a faulty set of data from which they're making judgments.

If you believe that the potential failure mode of a process is completely unacceptable, then it's perfectly logical to be dead set against that process. Think of a Hindu trying to convince an atheist to jump off a cliff, because, the Hindu says, if it doesn't work you'll just come back as something else, so what's the risk? The atheist, however, considers the failure mode completely unacceptable, and will, rightly, refuse the gamble.

Same thing with many opponents of nuclear power. They're not dumb, they just think a nuclear accident is an epic catastrophe. Under those circumstances, flat-out opposition is a reasonable position.

As we've recently read on slashdot, trying to use facts to change their minds *probably* won't work.

But calling them anti-braincell *certainly* won't.

Re:Not true

[Graff]

Really? and how would keep anyone from taking the whole thing breaking it apart somewhere else and selling the valuable fuel grade uranium on the black market?

Or worse yet, using the uranium and all the radioactive parts of the reactor for a dirty bomb?

Or even worse yet, trying to do one of the above, but fucking up and letting all kinds of radioactive liquids drain in the drinking water underground?

In most of these small reactor designs the fissionable material has nearly no value as a weapon. For example, a Pebble Bed Reactor uses balls of graphite and fissionable material which can be difficult to re-process into something other than fuel. A dirty bomb is of little concern because, again, it's much easier to just mine new material rather than use the fuel for these reactors.

Lastly, the modern designs for reactors are extremely safe. They have less chance of contaminating groundwater supply than building solar panels (a process that requires tons of heavy metals, organic wastes, and wastewater) or operating a coal-fired power plant. Not to mention that once you are done using the fuel and reprocessing it into new fuel you are left with a small amount of concentrated waste with either extremely short (degrades quickly to harmless elements) or extremely long (emits nearly no radiation) lifetimes.

The modern nuclear reactor designs are vastly better than the units built 40+ years ago, it's a shame that we haven't been building them. Instead we are maintaining older units because the red tape is too much to bother building new units to replace the aging ones. THAT'S your recipe for disaster!

Deepwater Horizon Blowout

[chebucto]

Why not call it the Deepwater Horizon blowout? That's the phrase everyone else seems to be using.

It's more specific than 'BP Blowout' (for obvious reasons)

It's also more specific than 'Macondo Blowout' (The Macondo Prospect, as wikipedia tells me, is the name of the field, which presumably might still have another blowout at some point in the future. Deepwater Horizon, having sunk to the bottom of the ocean, is unlikely to have any future blowouts.)

Re:I'll just pick on one obvious mistake

[Nadaka]

And that is why you toss it back into a feeder reactor as fuel to and let the neutron radiation break it down for you.

Hopeful dreaming and not a done deal

[dbIII]

I suggest watching the current Russian efforts at getting a large liquid sodium reactor going before putting all your faith in such a thing. There are major problems to solve that the French and the US were unable to sort out in the 1990s that made such a technology unworkable at a large scale, that's the real story behind the cancelled program. If the Russians can get it to work or some local R&D can solve the problems you'll have something to talk about, but for now what you are selling as a done deal is nothing but hopeful dreaming.

IFR cancelation:

[Hartree]

I thought it was interesting the reason given when the cancellation of the IFR was mentioned in Clinton's first state of the union speech. It was that we would never need it, and thus it was a waste of money.

To say the least, I disagreed.

Unit size

[Animats]

There are a few useful sizes at which to build such things as nuclear reactors. One useful size is what can be transported on a railroad car or a heavy-equipment transporter truck. That's as big as you can get and still build the thing in a factory, which has substantial cost advantages over on-site construction. The upper limit for this seems to be around 135 MWe.

Wind turbines have a size problem, too. Somewhere around 3MW, they become too big to transport assembled by road or rail, even with the blades shipped separately. Better generator design seems to help with this. Enercon has been able to get up to 10MW or so with a no-gearbox generator design and still ship the parts by road. The very large machines require more on-site assembly.

Russian and Japanese experience:

[Hartree]

You mean like the liquid sodium Russian BN600 (600 MW electric fast breeder power plant) that's been running since 1980?

It's had some problems, but nothing that couldn't be repaired and put back online.

Or maybe like the Japanese Monju plant? It had a sodium fire, but that was due to a bad design on a temperature sensor rather than anything to do with sodium itself as a coolant. It's back online now. Much of the reason it took so long was due to a scandal with the management covering up and the resulting court cases. It wasn't the technical problems that stopped it for all that time but the legal/political ones.

Sodium reactors have been around since the 50s at least. Yes, there are problems with embrittlement and the reactivity of the coolant, but it's hardly a show stopper. They're known and manageable problems.

What led to the shutdown of the program was the opposition of John Kerry and others, not technical problems with the sodium coolant.

Sodium coolant neutron activation: non-issue:

[Hartree]

Yes, sodium gets activated by the neutrons. Yes, it's highly radioactive then. But, it's quite short lived (15 hours for Na-24, 2.6 years for Na-22) so it's not as big a problem as you imply. Na-22 is a beta decay, so that's not problematic. Na-24 is the one that has dangerous radiation as it emits gammas. But with a 15 hour half life, it decays very quickly.

The daughter products aren't a problem either (Ne-22 and Mg-24), they're both stable.

Thorium Power

[hydromike2]

The future of energy is in thorium. It a) cant be weaponized, b) is cleaner, c) does not need to be throttled up like uranium. They are developing these plants in other parts of the world such as india.

Re:put them all over as the power grid is not setu

[HungryHobo]

In the US in situ leaching is used.
Basicly you pump a mix of water and baking soda into the ground and the uranium disolves in it.
Then you pump it back up and extract the uranium.
Baking soda isn't high on my list of things I'm afraid of getting in my water.
Pretty clean and safe.

waste storage wouldn't be too hard if it was treated as a technical problem, unfortunatly politicians who consider the words "nuclear" and "satanic" interchangable screwed that one up.

Your sig

[Cro Magnon]

You couldn't have a better sig for that post!