I'm not asking for anything, I just described ONE POSSIBLE technology that Hitachi could be working on. Honestly I don't know a large amount about the safety characteristics of such a reactor, but it doesn't appear to be 'vast'. I'd suggest doing some general reading on the subject. These ARE liquid metal cooled reactors, with all that implies and I'm NOT saying I think they would be safe, etc. Don't mistake me for one of the blind followers of the nuclear light. I don't think all nuclear power is The Devil necessarily, but I'm a pretty deep skeptic on the subject. Still, I can see the allure of a technology that could in principle supply 'clean' power for 1000's of years using nothing but existing stockpiles of a substance that is generally considered useless and could burn up troublesome waste.

Sounds good to me, let me know when you have a design and I'll fund it!

The implementations I've seen bandied about are primarily 'TWR' type designs where the fuel is roughly 90% U238 and 10% U235 or Pu238. These are ESSENTIALLY fast breeders, but they are capable of burning up about 35% of their fuel in a single cycle. The resulting spent fuel can be remelted and recycled through the reactor without chemical separation. Because existing spent fuel from LWRs is still mostly fertile U238 it can be utilized directly to feed a TWR. Obviously a TWR wouldn't be 'waste free', there will be daughter elements produced as in any reactor, etc. In fact it has been characterized as a rather tricky type of reactor to build, even for a breeder, and eventual decommissioning would be fairly nasty. HOWEVER due to the vastly high fuel use efficiency a TWR could essentially just be fueled once and sealed with no provision for refueling at all. Conceivably the core could be designed such that it would simply be removed and replaced after 40 years, at least in theory. Reality is more like you'd end up with a very hot core that would still have to be disposed of, but this would amount to a very much smaller amount of waste than with an LWR. The beauty of this sort of system is that you can burn depleted Uranium there are VAST stockpiles of the stuff around, enough to fuel 1000's of TWRs for millennia (the US alone has over 700,000 tons in inventory).

I'm not advocating these things, but if some similar sort of design is what Hitachi is talking about, then it certainly would be able to burn waste. I can see the lure. I suspect there are a lot of these heavy industry corporates that have nuclear expertise that are keeping these kinds of projects on low simmer somewhere thinking that maybe in a decade or two the world will be banging on their door desperate for a clean energy solution and willing to put up with nuclear power. Its possible they are right. Frankly though I doubt they will push it through to an actual build of anything in today's climate, but perhaps in 5 or 10 years when they are good and ready things will be different. At least by then they may have a good idea whether such a concept is really economical.

238U isn't a transuranic, by definition. You CAN OTOH burn up Pu 239, Americium, etc much faster than it would decay if you have a good neutron flux. I don't know of anyone who doesn't believe something like a 'traveling wave' reactor, or a fission/fusion hybrid wouldn't WORK, its just a matter of if it would produce economical results vs just burying the waste in a repository.

Purex is a process, not just the place in Hannford where they ran it at one time. Its an example of what highly radioactive materials processing is like.

You have to understand, I've BEEN to some of these places. I've SEEN IT. I know what the physics is and the chemistry and a fair amount about the engineering. This level of radioactivity is devilishly hard to completely contain and when even relatively small amounts escape you have nightmares like groundwater contamination and fun things like that. Its NOT easy like you seem to think. You need to study the subject instead of just some idiot's hype about it.

And again, I'm not saying it can't be worth it. Maybe it IS worth it, but I can guarantee you there will be billions and billions spent on controlling the resulting mess. Its just the nature of the beast. If spending $40 billion on building and cleaning up such a facility saves $200 billion and there isn't a big environmental problem left over afterwards then fine, its worth it. You simply cannot automatically assume that will be the case. I'm sure Hitachi looked into it, but I would be careful to see what they were reporting internally to their board BEFORE they decided to go ahead, because that will be the conservative and less biased view of it. Once they get going its all gung-ho with these corporations. You really have to watch what they put out at that point, its often very optimistic at best.

Well, first of all I didn't say the whole area would be waste. I said the structures and etc would be waste. Of course nobody knows exactly what that would entail, no such facility has been built, but when I look at existing purex plants and other similar infrastructure that has handled high level waste and performed any sort of significant handling, it has turned out to be a very big mess. All I'm suggesting is that we have to consider this when we think about 'burning waste' and such things. I MAY not turn out to be the deal that its proponents claim. We don't know yet. That doesn't make me pro or anti nuclear, it makes me an intelligent human being who weighs all sides of an issue before declaring that its good or bad. When the evidence is in, then I'll decide. Until then I just point out the pros and cons and maybe what we can guess about their merit. You can do no better unless you have some font of otherwise secret knowledge about this subject that the rest of the world is lacking.

Or its a nuclear chemist telling you how it really is. Gosh, sorry the world doesn't conform to your desires...

Windmills and solar plants may have to be dismantled someday, but they don't have effectively a finite lifespan due to extreme safety concerns which nuclear plants do, so the chances are slim that they WILL be retired. When elements of such plants DO get demolished this is just an ordinary demolition project and the leftovers are either recycled, used for fill, or etc. as appropriate. In the case of all of the operating equipment part of a nuclear power plant ALL OF IT is low level waste and has to be disposed of in specific ways. You don't have to believe me, just go and investigate for yourself. Now, the employee parking garage and some offices over on the other side of the site? Maybe not, they're probably just going to the landfill. However, at ALL FACILITIES that have dealt with some sort of processing of transuranics and longer-lived daughter elements very expensive cleanups have been required. Vastly more expensive than the often billion-dollar cleanups at power reactors. It is absolutely certain that anyplace that is opening casks and moving the stuff around that is inside them will have to do some chemistry on what's in there, and when they do they WILL MAKE A NASTY MESS. If you don't understand this, then you're too ignorant of the subject to be commenting.

Well, even 10k or 100k yr half-lives are not so good, and even Pu is BAD STUFF in the wrong context. Eat some and you might as well dig your own grave. OTOH its not so hard to handle. Its all messy, and the truth is that for a lot of the really low level stuff the best option would be to just dilute it to oblivion, burn it in some remote place, etc. Most of the low-level waste really is not that bad and the levels are minute.

Exactly! In terms of expense of dealing with radiation 100 years and 100k years isn't that much different from our perspective. In either case you want to contained, well contained. Honestly, transuranics are surely more expensive to house to some extent, but the question is if the extra cost is more than the cost of burning plus cooling/disposal/cleanup of these high neutron flux reactor designs.

Mmmmmm, no, you can definitely burn up transuranics and you pretty much HAVE to end up with less at the end of the day, but the question is whether or not you have LESS OF A PROBLEM at the end of the day because there are plenty of "short lived" radionuclides that you really would rather trade for some nice plutonium or americium. On top of that the entire structure, premesis, possibly nearby things, etc will become waste, and even low level waste is costly to deal with. This is the same sort of set of issues that have made it totally uneconomical to reprocess spent fuel. ANY handling is messy, dangerous, and produces a lot of expensive to dispose of waste.

I have an Asus Z87 board, absolutely no problems whatsoever. I've booted several distros on it and it just works.

Well, it sounded pretty clear that the actual flight CONTROL software worked fine and executed a program perfectly, it just wasn't the program that was intended due to SOME sort of issue with another piece of 'management' software. It sounded like that was also in the spacecraft, but its just as likely it was something running at ground control (makes more sense to me, generally you only run the least amount of software onboard that you can, why waste money on CPU and etc that could be cheaper ground stuff?).

Exactly, and for every other industry where you have critical systems that are microprocessor based you have equivalent frameworks. There are 1000's of CPUs in your average rocket or aircraft. Their software is all designed to EXTREMELY tight specifications and under very specific processes and rules. The teams of people who do this work are experienced, stable, very skilled, and have implemented very exacting processes mandated by the FAA or military. The sorts of failures the Russians are having just don't happen these days. Back in the 60's and 70's there were some incidents of bad flight software on spacecraft, but nowadays US systems are almost 100% reliable in that sense.

Ah, I just love these sorts of pronouncements.

When was the last time you heard of a 747 crashing because of a software glitch? My first job was to verify the design and implementation of a major part of the flight software for that aircraft, so I'm kind of an expert on this subject. You have no idea how multi-faceted and sophisticated the verification and SQA processes are on these projects. First of all formal logical methods are used to design and validate all the control algorithms. Then the actual system is designed, with different subsystems being individually broken out and decomposed to the component (software and hardware) level so that a complete description is created, including every single state, all modes of operation, all possible conditions under which the aircraft could operate, etc. Then the various components are designed. During that design process a complete set of failure mode analyses are performed. For every single combination of components in the system it is determined what the individual effects of failure of each one in all possible modes of failure would be, then a fault tolerance matrix is constructed which allows the analysis of all possible combinations of failures and their effects.

Then I come in. I construct a complete simulation of the actual aircraft electrical and mechanical systems and its flight control system. Now I can literally put each card, box, subsystem, etc into a virtual aircraft and test it to determine that it ACTUALLY performs as predicted under at least the vast majority of these conditions and failure modes. This is all IN PARALLEL with the formal SQA process for the flight software in which each module is tested with all possible inputs, formal static code analysis is performed, etc.

We didn't HAVE errors. In all the millions of lines of code that was ever under my jurisdiction we never passed a single piece of code that had any error in it that could ever effect the safety of flight of any of the 7+ aircraft that I worked on. I'm not saying everything was always perfect. There were times when we found that flight software had issues, that there were system level issues that weren't discovered in design/test/review, but they were never things that went into a production aircraft and caused a problem that could have resulted in the aircraft being lost or even not flying that day.

The upshot of all this is I know something about quality of software. Russia's aerospace industry has a very serious issue, this is only like the 4th lost mission in the last couple years that I can count without even trying. They have to be cutting some serious corners and its BAD.

I've been hearing all this about the much vaunted chops of these Russian coders, but frankly I don't ever see it. They obviously haven't even heard of SQA. What gives?