Fair point. I barely consider reactors that need control rods as a legitimate design, there are much better ways to build a reactor that doesn't need to depend on such things for safety. Basic design using a molten salt core should be more than enough, and in any case none of them are anywhere near the chain reaction that would be in a nuclear bomb.

Coal is responsible for many orders of magnitude more deaths and radioactive emissions than all nuclear incidents combined. But people don't care about simple things like facts or numbers. Talking about renewables when a significant portion of baseload power is still produced by coal is pointless. Let people have their feel good green tech (made in China, powered by a lot of coal of course ; ), but replace coal with modern nuke.

Denying the place of recent generation nuclear power as a viable strategy of supplying cleaner baseload power is much like denying man made climate change. Fucking moronic.

Thorium salt reactors do produce waste, but it's incredibly safe compared to breeder/lwr reactor byproducts. In fact, you can introduce older reactor waste in to the liquid mix in small amounts and the LFTR will break it down to less harmful components by accelerating decay in the core.

http://lftrnow.com/

"LFTRs can also burn radioactive “waste” we are currently storing, made from the LWR units of today. We could actually reduce our radioactive waste using LFTRs and other Molten-Salt Reactors (MSRs) (more: https://www.youtube.com/watch?v=i1fqB6p9pgM)."

So LFTR is a strategy for both power supply and cleaning up existing waste storage. Who'da thunk it??

I recently saw a contemporary video about how molten salt nuclear fission is much less risky in terms of meltdowns (not possible) and waste (much more manageable, and some waste products even being useful), and that this now seemingly abandoned method of nuclear energy might be the answer to many of our energy problems today. Does anyone know more about this? Is it a better alternative indeed? This video is a bit too technical for me, but I'd still like to think that this is a forgotten method of generating energy that might save us from completely wrecking the climate...

Your video, Molten salt + Water = Explosion (full awesome version), has made it into the Top 15 New Videos listing. Congratulations on your achievement. For your contribution you have been awarded 1 Power Point.

The full version - watch! *related=http://videosift.com/video/Molten-salt-Water-Explosion-full-awesome-version

Molten salt + Water = Stand back! (teaser) has been added as a related post - related requested by Zawash on that post.

Molten salt + Water = Explosion (full awesome version) has been added as a related post - related requested by Zawash.

Your video, Molten salt + Water = Stand back! (teaser), has made it into the Top 15 New Videos listing. Congratulations on your achievement. For your contribution you have been awarded 1 Power Point.

This could use some better explanation, and some footage of the first 2 tries where nothing happened. What was different the 3rd time?

Just from observation I'll hazard a guess, it seemed the salt may have trapped some water inside the blob which flashed to steam, causing a small explosion and dispersing the molten salt into the water and super heating a large area of water to steam in an instant, causing the large explosion.

That may be totally wrong, it's just a guess, but something extremely hot causing water to 'explode' is hardly "inexplicable".

Indeed, I am all for reactor simplification, the reactor I want to see constructed could theoretically be nearly completely made on a factory line then shipped and installed very simply. The molten salt reactor concept is just a bunch of pipes with a graphite core. Most of the Gen4 reactors have this goal, and while large construction projects do mean jobs, usually good jobs...they are also costs, and if we want China and India to adopt greener power systems, they need to be cheaper than coal.

http://www.youtube.com/watch?v=N2vzotsvvkw

I am going to sift this after I post, but it is a short look into reactors in general, and why the MSR and other potential Gen4 concepts could eliminate that huge capital and labor cost. And nearly completely eliminate radioactivity problems to the general public.

300 billion is actually not to much money when you get down to it. Each year, the global economy spends up to 10 trillion dollars on dino fuel technology. Considering the reliability of NPPs and the nearly 90% load rate over the course of many years...those costs are really really good! Typically speaking, when you consider the costs of decommissioning, waste transportation, nuclear generally ends up being about on par with coal...mostly because nuclear plants last so darn long, over 60 years for some of our gen2 plants in the US and still going strong! Compare that to the 150 billion or so Germany has spent on solar project to their total ACTUAL output and it is a very telling tail. Even more so when you look at total carbon emissions of Germany compared to France.

Waste is actually what made me anti-nuclear myself. My introduction to caring (negatively) about nuclear was the Fukushima Daiichi incident. But after learning more about that situation, I actually really started to appreciate nuclear more. No one died as a result of FD failure, the containment building stopped most of the most harmful radiation, and the stuff that did get out is the really mild stuff (stuff with the million year half lives). I don't want to downplay this, it is still a very serious industrial mess to clean up, but compared to the 20 thousand people who died in the Tsunami and the tons of fuels, trash and other crap that got souped around in Japan as a result, the old reactor help up respectably, and is a credit to the operators (all of whom are currently alive an well).

I had a common misconception about radioactivity, I thought something with a long half-life was bad because it was going to be radioactive for a long, long time. That is mostly wrong. What that means is it is going to be hardly radioactive for a long time, elements that are short lived are VERY radioactive, but disappear very fast. I don't want to mire you in most of the gritty details, but the fission products reactors produce don't last very long, most only hours, a fewer some decades, and only a few longer than that. Stuff that has billion year a billion year half life...well, you don't really need to worry about it at all, it just isn't that radioactive. Most of the worry is based around "transuranics". That is just fancy speak for "stuff heavier than uranium". This is the stuff like Plutonium and Curium ect. The great thing about modern, Gen4 reactors is they don't really make those things...the thorium reactor I like starts with thorium, which is a long, long way from making anything heavier than uranium (less than 1% theoretically possible). So micrograms per year...not really that much to worry about (there is also no way to really get that to go into the environment because we don't use pressure vessels, but I will leave that to Kirk to explain).

I don't want to make it sounds like there isn't any risk or anything, but the risks have been way overplayed by political interests and not technical ones. For instance, many of the exclusions zones for FD were way overblown, they were no more radioactive than my home in the mountains ...but that isn't want you heard in the news.

But I think I will leave it like that. Nuclear has a bunch of mystic joojoo around it. Don't take my work for it, please, give "bill gates nuclear" a google, or other "gen4 reactor" stuff a chance before you completely write off nuclear as a green option for the future. I personally think it will have a big role to play if we want to stem off CO2 production AND bring more people into a western quality of life. Thanks again for the back and forth.

@radx No problem on the short comment, I do the exact same thing

I find your question hard to address directly because it is a series of things I find kind of complexly contradictory. IE, market forces causing undesirable things, and the lack of market forces because of centralization causing undesirable things. Not to say you are believing in contradictions, but rather it is a complex set of issues that have to be addressed, In that, I was thinking all day how to address these, and decided on an a round about way, talking about neither, but rather the history and evolution as to why it is viewed the way you see it, and if those things are necessarily bad. This might be a bit long in the tooth, and I apologize up front for that.

Firstly, reactors are the second invention of nuclear. While a reactor type creation were the first demonstration of fission by humans (turns out there are natural fission reactors: Oklo in Gabon, Africa ), the first objective was, of course, weapons. Most of the early tech that was researched was aimed at "how to make a bomb, and fast". As a result, after the war was all said and done, those pieces of technology could most quickly be transitioned to reactor tech, even if more qualified pieces of technology were better suited. As a result, nearly all of Americas 104 (or so) reactors are based on light water pressure vessels, the result of mostly Admiral Rickover's decision to use them in the nuclear navy. This technological lock in made the big players bigger in the nuclear field, as they didn't have to do any heavy lifting on R&D, just sell lucrative fuel contracts.

This had some very toxic effects on the overall development of reactor technology. As a result of this lock-in, the NRC is predisposed to only approving technology the resembles 50 year old reactor technology. Most of the fleet is very old, and all might as well be called Rickover Reactors. Reactors which use solid fuel rods, control rods, water under pressure, ect, are approved; even though there are some other very good candidates for reactor R&D and deployment, it simply is beyond the NRCs desire to make those kinds of changes. These barriers to entry can't be understated, only the very rich could ever afford to attempt to approve a new reactor technology, like mutli-billionaire, and still might not get approved it it smells funny (thorium, what the hell is thorium!)! The result is current reactors use mostly the same innards but have larger requirements. Those requirements also change without notice and they are required to comply with more hast than any industry. So if you built a reactor to code, and the wire mesh standards changed mid construction, you have to comply, so tear down the wall and start over unless you can figure out some way to comply. This has had a multiplication effect on costs and construction times. So many times, complications can arise not because it was "over engineered", but that they have had to go super ad-hawk to make it all work due to changes mid construction. Frankly, it is pretty amazing what they have done with reactor technology to stretch it out this long. Even with the setbacks you mention, these rube goldbergian devices still manage to compete with coal in terms of its cost per Kwh, and blow away things like solar and wind on the carbon free front.

As to reactor size LWRs had to be big in the day because of various reasons, mostly licencing. Currently, there are no real ways to do small reactors because all licencing and regulatory framework assumes it is a 1GW power station. All the huge fees and regulatory framework established by these well engineered at the time, but now ancient marvels. So you need an evacuation plan that is X miles wide ( I think it is 10), even if your reactor is fractionally as large. In other words, there is nothing technically keeping reactors large. I actually would like to see them go more modular, self regulating, and at the point of need. This would simplify transmission greatly and build in a redundancy into the system. It would also potentially open up a huge market to a variety of different small, modular reactors. Currently, though, this is a pipe dream...but a dream well worth having and pushing for.

Also, reactors in the west are pretty safe, if you look at deaths per KWH, even figuring in the worst estimates of Chernobyl, nuclear is one of the best (Chernobyl isn't a western reactor). Even so, safety ratcheting in nuclear safety happens all the time, driving costs and complexity on very old systems up and up with only nominal gains. For instance, there are no computer control systems in a reactor. Each and every gauge is a specific type that is mandated by NRC edict or similar ones abroad (usually very archaic) . This creates a potential for counterfeiter parts and other actions considered foul by many. These edicts do little for safety, most safety comes from proper reactor design, and skillful operation of the plant managers. With plants so expensive, and general costs of power still very competitive, Managers would never want to damage the money output of nuclear reactors. They would very much like to make plant operations a combination of safe, smooth, and affordable. When one of those edges out the other, it tends to find abuses in the real world. If something gets to needlessly costly, managers start looking around for alternatives. Like the DHS, much of nuclear safety is nuclear safety theater...so to a certain extent, some of the abuses don't account for any real significant increase in risk. This isn't always the case, but it has to be evaluated case by case, and for the layperson, this isn't usually something that will be done.

This combination of unwillingness to invest in new reactor technology, higher demands from reactors in general, and a single minded focus on safety, (several NRC chairmen have been decidedly anti-nuclear, that is like having the internet czar hate broadband) have stilted true growth in nuclear technology. For instance, cars are not 100% safe. It is likely you will know someone that will die in a car wreak in the course of your life. This, however, doesn't cause cars to escalate that drastically in safety features or costs to implement features to drop the death rate to 0. Even though in the US, 10s of thousands die each year in cars, you will not see well meaning people call for arresting foam injection or titanium platted unobtanium body frames, mainly because safety isn't the only point of a car. A car, or a plane, or anything really, has a complicated set of benefits and defects that we have to make hard choices on...choices that don't necessarily have a correct answer. There is a benefit curve where excessive costs don't actually improve safety that much more. If everyone in the USA had to spend 10K more on a car for form injection systems that saved 100 lives in the course of a year, is that worth it? I don't have an answer there as a matter of fact, only opinion. And as the same matter of opinion on reactors, most of their cost, complication, and centralization have to do with the special way in which we treat reactors, not the technology itself. If there was a better regulatory framework, you would see (as we kind of are slowly in the industry despite these things) cheaper, easier to fabricate reactors which are safer by default. Designs that start on a fresh sheet of paper, with the latest and greatest in computer modeling (most current reactors were designed before computer simulations on the internals or externals was even a thing) and materials science. I am routing for the molten salt, thorium reactors, but there are a bunch of other generation4 reactors that are just begging to be built.

Right now, getting the NRC to approve a new reactor design takes millions of dollars, ensuring the big boy will stay around for awhile longer yet. And the regularly framework also ensures whatever reactor gets built, it is big, and that it will use solid fuel, and water coolant, and specific dials and gauges...ect. It would be like the FCC saying the exact innards of what a cellphone should be, it would be kind of maddening to cellphone manufacturers..and you most likely wouldn't have an iPhone in the way we have it today. NRC needs to change for any of the problems you mentioned to be resolved. That is a big obstacle, I am not going to lie, it is unlikely to change anytime soon. But I think the promise of carbon free energy with reliable base-load abilities can't be ignored in this green minded future we want to create.

Any rate, thanks for your feedback, hopefully, that wasn't overkill

Safe nuclear refers to many different new gen4 reactor units that rely on passive safety instead of engineered safety. The real difference comes with a slight bit of understanding of how nuclear tech works now, and why that isn't optimal.

Let us first consider this, even with current nuclear technology, the amount of people that have died as a direct and indirect result of nuclear is very low per unit energy produced. The only rival is big hydro, even wind and solar have a great deal of risk compared to nuclear as we do it and have done it for years. The main difference is when a nuclear plant fails, everyone hears about it...but when a oil pipeline explodes and kills dozens, or solar panel installers fall off a roof or get electrocuted and dies...it just isn't as interesting.

Pound per pound nuclear is already statistically very safe, but that isn't really what we are talking about, we are talking about what makes them more unsafe compared to new nuclear techs. Well, that has to do with how normal nukes work. So, firstly, normal reactor tech uses solid fuel rods. It isn't a "metal" either, it is uranium dioxide, has the same physical characteristics as ceramic pots you buy in a store. When the fuel fissions, the uranium is transmuted into other, lighter, elements some of which are gases. Over time, these non-fissile elements damage the fuel rod to the point where it can no longer sustain fission and need to be replaced. At this point, they have only burned about 4% of the uranium content, but they are all "used up". So while there are some highly radioactive fission products contained in the fuel rods, the vast majority is just normal uranium, and that isn't very radioactive (you could eat it and not really suffer any radiation effects, now chemical toxicity is a different matter). The vast majority of nuclear waste, as a result of this way of burning uranium, generates huge volumes of waste products that aren't really waste products, just normal uranium.

But this isn't what makes light water reactors unsafe compared to other designs. It is all about the water. Normal reactors use water to both cool the core, extract the heat, and moderate the neutrons to sustain the fission reaction. Water boils at 100c which is far to low a temperature to run a thermal reactor on, you need much higher temps to get power. As a result, nuclear reactors use highly pressurized water to keep it liquid. The pressure is an amazingly high 2200psi or so! This is where the real problem comes in. If pressure is lost catastrophically, the chance to release radioactivity into the environment increases. This is further complicated by the lack of water then cooling the core. Without water, the fission chain reaction that generates the main source of heat in the reactor shuts down, however, the radioactive fission products contained in the fuel rods are very unstable and generate lots of heat. So much heat over time, they end up causing the rods to melt if they aren't supplied with water. This is the "melt down" you always hear about. If you start then spraying water on them after they melt down, it caries away some of those highly radioactive fission products with the steam. This is what happened in Chernobyl, there was also a human element that overdid all their safety equipment, but that just goes to show you the worst case.

The same thing didn't happen in Fukushima. What happened in Fukushima is that coolant was lost to the core and they started to melt down. The tubes which contain the uranium are made from zirconium. At high temps, water and zirconium react to form hydrogen gas. Now modern reactor buildings are designed to trap gases, usually steam, in the event of a reactor breach. In the case of hydrogen, that gas builds up till a spark of some kind happens and causes an explosion. These are the explosions that occurred at Fukushima. Both of the major failures and dangers of current reactors deal with the high pressure water; but water isn't needed to make a reactor run, just this type of reactor.

The fact that reactors have radioactive materials in them isn't really unsafe itself. What is unsafe is reactor designs that create a pressure to push that radioactivity into other areas. A electroplating plant, for example, uses concentrated acids along with high voltage electricity in their fabrication processes. It "sounds" dangerous, and it is in a certain sense, but it is a manageable danger that will most likely only have very localized effects in the event of a catastrophic event. This is due mainly to the fact that there are no forces driving those toxic chemical elements into the surrounding areas...they are just acid baths. The same goes for nuclear materials, they aren't more or less dangerus than gasoline (gas go boom!), if handled properly.

I think one of the best reactor designs in terms of both safety and efficiency are the molten salt reactors. They don't use water as a coolant, and as a result operate at normal preasures. The fuel and coolant is a liquid lithium, fluoride, and beryllium salt instead of water, and the initial fuel is thorium instead of uranium. Since it is a liquid instead of a solid, you can do all sorts of neat things with it, most notably, in case of an emergency, you can just dump all the fuel into a storage tank that is passively cooled then pump it back to the reactor once the issue is resolved. It is a safety feature that doesn't require much engineering, you are just using the ever constant force of gravity. This is what is known as passive safety, it isn't something you have to do, it is something that happens automatically. So in many cases, what they designed is a freeze plug that is being cooled. If that fails for any reason, and you desire a shutdown, the freeze plug melts and the entire contents of the reactor are drained into the tanks and fission stops (fission needs a certain geometry to happen).

So while the reactor will still be as dangerous as any other industrial machine would be...like a blast furnace, it wouldn't pose any threat to the surrounding area. This is boosted by the fact that even if you lost containment AND you had a ruptured emergency storage tank, these liquid salts solidify at temps below 400c, so while they are liquid in the reactor, they quickly solidify outside of it. And another great benefit is they are remarkably stable. Air and water don't really leach anything from them, fluoride and lithium are just so happy binding with things, they don't let go!

The fuel burn up is also really great. You burn up 90% of what you put in, and if you try hard, you can burn up to 99%. So, comparing them to "clean coal" doesn't really give new reactor tech its fair shake. The tech we use was actually sort of denounced by the person who made them, Alvin Weinberg, and he advocated the molten salt reactor instead. I could babble on about this for ages, but I think Kirk Sorensen explains that better than I could...hell most likely the bulk of what I said is said better by him



http://www.youtube.com/watch?v=N2vzotsvvkw

But the real question is why. Why use nuclear and not solar, for instance?

http://en.wikipedia.org/wiki/Energy_density

This is the answer. The power of the atom is a MILLION times more dense that fossil fuels...a million! It is a number that is beyond what we can normal grasp as people. Right now, current reactors harness less that 1% of that power because of their reactor design and fuel choice.

And unfortunately, renewables just cost to darn much for how much energy they contribute. In that, they also use WAY more resources to make per unit energy produced. So wind, for example, uses 10x more steal per unit energy contributed than other technologies. It is because renewables is more like energy farming.

http://videosift.com/video/TEDxWarwick-Physics-Constrain-Sustainable-Energy-Options


This is a really great video on that maths behind what makes renewables less than attractive for many countries. But to rap it up, finally, the real benefit is that cheap, clean power is what helps makes nations great. There is an inexorable link with access to energy and financial well being. Poor nations burn coal to try and bridge that gap, but that has a huge health toll. Renewables are way to costly for them per unit energy, they really need other answers. New nuclear could be just that, because it can be made nearly completely safe, very cheap to operate, and easier to manufacture (this means very cheap compared to today's reactors as they are basically huge pressure vessels). If you watch a couple of videos from Kirk and have more questions or problems, let me know, as you can see, I love talking about this stuff Sorry if I gabbed your ear off, but this is the stuff I am going back to school for because I do believe it will change the world. It is the closest thing to free energy we are going to get in the next 20 years.

In reply to this comment by ReverendTed:
Just stumbled onto your profile page and noticed an exchange you had with dag a few months back.
What constitutes "safe nuclear"? Is that a specific type or category of nuclear power?
Without context (which I'm sure I could obtain elsewise with a simple Google search, but I'd rather just ask), it sounds like "clean coal".

The actinides are, generally, "safe" to handle, like those Uranium Oxide pellets. You are more likely to damage the pellet with your nasty human oils than the uranium will you...unless you eat the whole thing, but its chemical toxicity will do you more harm that its radioactive toxicity. Uranium oxide just isn't that radioactive, that is why none of the containers or work areas were shielded in this lab.



Now, if they were dealing with a "hot" substance, one that has hard gammas (like when you do MOX fuel recycling), you have to take even greater precautions because then the radioactive problems really do start to show their heads. Not only will it damage your cells faster than they can repair, but it can start to take out unshielded electronics. This is generally only true for fission products, and a few actinides like protactinium which is highly radioactive AND chemically toxic, and generally only man-made (normal occurrences are less than a few parts per trillion in the crust).



These complications are pretty good generalization to why normal LWRs are not the best way to do nuclear, they just generate far to much waste compared to alternatives. You burn less than 1% of the mined uranium in current reactor tech and fuel cycle choices. With a thorium cycle in a molten salt reactor, you can burn greater than 90%, pushing up to 99% or higher if you try real hard. This means you generate an order(s) of magnitude less waste, and that waste generally is safe after about 300 years (radiation is about the same as naturally occurring radiation). There are also other alternates that use uranium in a faster spectrum that perform better than current tech.



A second age of the atom is fast approaching. Unfortunately, those great pioneers which made this industry in the shadow of "the bomb" failed to realize the full potential of e=mc^2. If nuclear power was developed along side the Apollo instead of the Manhattan project, we might already be in that future, alas...it was not to be.



Radiation is fascinating though! I used to believe what I read in the fear news about any radiation leading to death..turns out that isn't so true after all. The planet is a far more radioactive place then you normally consider, and FAR more radioactive when our primordial ancestors evolved. In fact, there are many people living today in what are dubbed High Background Radiation Areas that seem to suffer no ill effect, and some suggest, have lower rates of cancer than other groups. More studies need to be done, but initial findings fly in the face of the notion of radiation I grew up with (that it all is bad and it all kills you!) Some have even suggested that the creator of the entire model used for evaluating radiation risk knowingly lied about it. The entire basis for today's evaluation of radiological risk is evaluated by Muller's findings as supported by the National Academy of Sciences’ of the time. And in fact, might just be based in fear instead of evidence.



Perhaps ancient man went through the same struggles as he tried to adopt fire, some impassioned move against the dangers of fire prevented some groups from using fire and advancing their way of life. Fire, though, allowed the groups that adopted it to improve their life dramatically. The energy released from a fission event is over a million times more energy rich than any energy tech we currently use, imagine what that could mean for mankind. Fusion is over 4 times that of fission (but much harder), and antimatter over 2000x that of fission (and MUCH MUCH harder). Yes, the age of the atom has only just begun, and who knows were man will be a result? Don't settle for solar dandruff, the power of the atom will reign supreme.

Its a fluoride salt, which isn't particularly expensive but it IS corrosive. Research is ongoing in to materials that will handle it for a full 30+ year lifetime, it is certainly not a dealbreaker.
>> ^marinara:

they don't do it because you have to work w/ molten salt dissolved in fluorine.
not cheap.
Upvote for anything about aging nuclear power plants. Those plants are just going to break down before they hit 60 years old

they don't do it because you have to work w/ molten salt dissolved in fluorine.
not cheap.

Upvote for anything about aging nuclear power plants. Those plants are just going to break down before they hit 60 years old