My daughter was one of the operators of the TRIGA reactor at Reed college. Some of the students joked it was a Fisher-Price My First Reactor reactor :-) at only 250kW its small as reactors go, but also exceptionally interesting.
It is very disappointing how constricted the field of nuclear research is, as it is a demonstrably zero carbon footprint energy source. I understand the emotion that nuclear power evokes in people, I think the only way to combat the misperceptions is with improving results. I recognize I am a minority in that regard.
People saying nuclear power plants having zero carbon footprint aren't really according for the entire nuclear fuel chain. the energy-intensive stages of the nuclear fuel chain are building the power plant, uranium mining, and nuclear decommissioning.
I still think nuclear power has its place for example having nuclear reactors on warships let them stay out to sea as long as they have food. They make their own electricity and water from the reactor. Just not for widespread power plants.
I think the future is going to move away from power being generated in one place.
Of course, some of the work done in the construction/mining/decommissioning could be powered by electricity from other reactors, getting closer to carbon-zero.
But realistically, there is no extant electricity supply that has zero carbon costs over it's lifecycle. At least that I am aware of.
If you take a sandwich into the control room of a nuclear plant and eat it there and throw the wrapper in the bin, that's "low level nuclear waste". If you do the same in an airliner, your sandwich will be exposed to more radiation! but it's just litter.
Is this a real world problem with real world consequences?
It is my understanding that the nuclear waste can be stored safely without too much cost. It is also my understanding that there are ways to re-use the already used fuel rods, effectively 1) making them radiate less 2) getting "leftover" power from already consumed fuel.
Psychological footprint fueled by ignorance however... Well, that borders religiousness. Maybe education and awareness helps.
It can be stored safely, but so far a good waste solution hasn't been implemented, at least in the US. With the cancellation of Yucca Mountain, the current "interim" long-term storage plan is basically on-site dry cask storage scattered everywhere. The spent-fuel pools are an even bigger mess. Many of them are filling up, and fuel isn't being transferred from them to longer-term storage even when it could/should be, because operators want to reduce costs.
I don't think many experts are that happy with the current spent-fuel story. They vary in why they're unhappy, ranging from environmental worries (more common on the left) to theft/terrorism worries (more common on the right). But overall there is just way too much nuclear waste hanging out in suboptimal interim storage.
A non-US citizen here, so I have practically no understanding of the politics related to US nuclear power.
However, the Wikipedia article for Yucca Mountain nuclear waste repository seems to mention that the cancellation was for political rather than for technical reasons. Wouldn't this imply, that the opposing forces aren't technological, but rather political? As in, if there's will, the problem can be at least partially solved?
Oh, no disagreement there. I don't think there is in principle a problem with safely storing nuclear waste, in the sense that it would be technically impossible to do it or anything. The problem is that in practice the current solution is to have a bunch of it hanging out in "interim" storage that is not really well planned or designed as permanent storage. That's mostly a political problem, and secondarily an economic incentives problem.
It's yet another example of the brilliance of the American public when it comes to power. Shut down the nuclear plants! (spin up coal plants instead). Block Yucca Mountain! (pile up spent fuel in short-term storage instead). So on and so forth.
It's yet another example of the brilliance of the American politicians when it comes to power.
Fixed that for you. Coal plants aren't doing so well, either. President Obama has stated many times a major policy goal is to destroy the coal industry - lack of viable alternative not mattering.
Regarding storing spent fuel only in temporary ways, that's just a sad artifact of neither side being able to agree on any long term solution, so no real long term solution gets implemented, and the can gets kicked down the road. It's lunacy not to face reality.
Coal, oil and gas kill quite a number of people today, invisibly and at-semi-random. Say X people die.
If you had a power source that killed X/100 people. But to implement that power source, congress would have to introduce a bill in which every single person who had to die was named.
Could that power source be implemented in any democracy?
(not to say nuclear is exactly like this, just to say nuclear has a bit of this kind of problem and this kind of problem is very hard to solve)
The trouble is that $4/gal fuel and an endless series of petro wars barely moves the needle on solving the political problems. Be afraid of any force that makes nuclear power look sensible to Americans.
>Is this a real world problem with real world consequences?
Might not be where you live, but there's a real world evacuated zone in Chernobyl, with a 20 mile radius were "even today radiation levels are so high that the workers responsible for rebuilding the sarcophagus are only allowed to work five hours a day for one month before taking 15 days of rest. Ukrainian officials estimate the area will not be safe for human life again for another 20,000 years.".
Oh, and: in the United States alone, the Department of Energy states there are "millions of gallons of radioactive waste" as well as "thousands of tons of spent nuclear fuel and material" and also "huge quantities of contaminated soil and water."
But let's get creative about the realities of hazardous radioactive waste storage. It's not an impossible problem to solve, when you think about it pragmatically. It's difficult, expensive, requires material resources, expertise and dedication, but it's not impossible.
The typical and most reliable procedure for managing radioactive waste is vitrification: creating a purified mixture of molten glass and then introducing an evenly distributed non-critical ratio of hot waste material into the glass, and allowing it to harden into a solid glass object. The radioactive glass object is then carted off to a repository, for permanent storage, in accordance with the half life of the waste, which might be centuries or more. Vitrification is a safe way to prevent accidental criticality, so that all the waste stays cool and is easier to shield.
Generally underground storage sites are the most desirable locations for the final resting place of vitrified waste. This provides a simple barrier to the penetrating radiation that the waste may emit.
Security is essential to the storage of radioactive waste, since unaccounted waste means there's some nasty stuff floating around. This adds effort to maintaining a site.
Ventilation is necessary, since ionizing radiation produces an accumulation of fee oxygen and hydrogen by catalyzing moisture in the air. This means offgassing equipment is needed to ventilate the natural accumulation to prevent explosion hazards. This adds complexity to storage.
Degradation of construction is a long term pest, in that the site must be constructed of high quality, durable architectual members, equipped to last centuries, and not collapse within decades. This adds expertise and expense requirements.
Site selection should be a no brainer though. Consider that Ukraine can make some decent income off the tragedy of Chernobyl, given that they have an unusable sector of their territory relegated to the reactor sarcophagus. Yeah, the sarcophagus is impossible to manage above ground, but what about digging underneath it and excavating a massive permanent waste repository, and charging money for depositing waste there? Nobody wants anything to do with Chernobyl. It's a ghost town. Seems like a chance to employ the site as a massive underground waste repository.
Same goes for Fukushima. Take a geological survey of the site, design durable, earthquake-proof architecture for an underground repository, and charge money to dumpwaste there.
After construction completes, your budget mostly comes from staffing qualified nuclear engineers and security personnel. Little else is necessary. A nuclear reactor and research lab can provide power to the site and provide an intellectual basis to attract new staff. Doesn't this sound like a sustainable plan?
In America there has been this massive battle over Yuka Mountain. It's politically hazardous to store waste underneath otherwise uncontaminated land. The protest generally stems from the not-in-my-backyard philosophy. There are tons of superfund sites, that are doomed to contamination for decades because of simple bureacratic laziness. Most of them are pretty close to cities. I think America could probably find sites, but they usually get locked up in legal messiness that blows any deal. I think there are probably places that could accept waste, and there's no rational reason to care, but people fight it anyway, because everyone seems to enjoy irrational litigation as political sport as a sort of clerical version of new-deal make-work contruction projects. But I digress.
There are reasonable ways to confront the challenges of radioactive waste storage. Obstinate people use this objection as an example of an insurmountable challenge simply because they're stubborn.
There are superior solutions to vitrification. Synroc [1] is technically far superior as it puts the long lived isotopes into mineral phases in which they are stable, as opposed to metastable glass.
Once stablised as synroc it is simply a matter of storing the waste. Storing above ground (i.e. in a shed) seems to me to be a better solution than pursuing geologic disposal, given the waste is now stable, and can be easily monitored.
Good point! Water table contamination is yet another hazard.
Fukushima is situated on the coast line, and already leaks into the ocean, but Chernobyl is near the Pripyat river, and is a tributary to the Dnieper River, which empties into the Black Sea. The Pripyat is contaminated within the exclusion zone, but it would be bad news to disturb and agitate any contamination, and make things worse.
Given that it's already a bad situation, and that natural leeching is already taking place by doing nothing, any engineering project would have to approach the site carefully so that leeching is not accelerated.
Yucca mountain is located in the southwest desert, so that mitigates water seepage, but Yucca mountain isn't a disaster site (yet), so that technical challenge can be tackled before it arises.
Say what you like about the strength of the evidence linking burning of hydrocarbons and climate change, but it doesn't carry the risk of a meltdown leaving a footprint so big and dangerous that cities have to be abandoned. I don't think it's "ignorance... that borders religiousness" that keeps the field of nuclear research heavily constrained and very expensive.
What relevance does Chernobyl have with modern nuclear power plants?
A honest question, because I am under an impression that with modern regulations and reactor designs the chance of a meltdown or less severe nuclear disaster are infitesimally small, granted that 1) regulations are being followed(which they weren't in Chernobyl) 2) safety of operation is being maintained and that the plant itself isn't faulty(which again wasn't case with Chernobyl).
>What relevance does Chernobyl have with modern nuclear power plants?
The relevance that Chernobyl was too promoted as safe, like "modern power plants" are.
Plus the relevance that power plant contractors and governments STILL bullshit people all the way to the bank, with friendly experts paid to downplay the dangers.
Just watch the misinformation and lies told by the Japanese officials on the Fukushima distaster in order to cover up their failings.
I trust in science as much as everyone else.
Building a nuclear reactor is not science alone.
It's business (e.g contractors cutting corners whenever they can make money), it's politics, it's marketing, it's trust on certain things not happening (e.g a huge earthquake or a tsunami as in Japan's case, or maybe an attack), it's faith in the human operators and the software used, and tons of other factors.
I'd rather not put faith in all those coinciding happily when the outcome can be potentially lethal.
What relevance does Chernobyl have with modern nuclear power plants?
In line with this notion, I am reminded of automobiles. Automobiles of yesteryear were more dangerous and significantly more polluting (causing serious health problems for the residents of Los Angeles). But of course we clearly cannot point to a '57 Chevy with no seatbelts or catalytic converter and say, "Clearly cars are too dangerous and noxious to allow".
Agreed, I think many people don't realize the enormous cost of an accident like Chernobyl, and that wasn't even the worst case scenario even though it was pretty bad.
I think the biggest problem is to guarantee that some future civilization will not dig up the waste believing it to be valuable, like we did with the old Egyptian graves. We could make it very difficult to do so, but it's not a "solved problem". http://vimeo.com/55736976 is an interesting watch (although perhaps a bit biased).
It's a solved problem. Dilute it with sand until it is about as radioactive as the original ore, melt the sand, and dump the chunks of glass someplace out of the way. Yes, future generations will need to protect themselves from it, but they already need to in huge areas where the ground emits radon.
If you read the article you will read about two reactors that are actually fueled by what we consider waste today.
That we don't completely burn the fuel used in a reactor is a 'bug', a misfeature if you will. That was expedient when the initial reactors were being brought online and now is a regulatory pain in the butt. There is nothing in the physics that requires a nuclear reactor complex to generate nuclear waste of any kind[1]. Only in the regulations.
[1] Nuclear incineration of even low level waste can effectively convert anything that was once radioactive into short lived nucleotide. Converting everything burned into its lowest energy stable state. But we don't do that either.
The fact that a reactor is fueled by waste doesn't mean it doesn't create waste or have a waste-disposal aspect.
In the case of any nuclear reactor, the vessel and mechanism itself becomes radioactive and must be disposed of (the same process also leads to embrittlement and other issues with the vessel/structure itself). And the resulting fission products are also still radioactive and require disposal, though my understanding is that thorium designs tend to produce lower quantities with lesser radioactivity than other designs. Or at least, that's the PR / theory, as the designs haven't been put into production use.
Nuclear power in general has been a huge exploration of unintended consequences.
As opposed to coal, oil and gas fracking? I sure rest assured that when the local groundwater and aquifiers for my city are too toxic to drink, well at least I'll only be dying of organic and heavy metal poisoning.
If you want to know, rather than project on me, my beliefs, you could ask me. As it happens, my view is that humans, as with other life forms, exist to perform the function of exploiting low-entropy energy stocks and flows. The consequences of that ... tend not to be something we consider in advance. We've benefited hugely from fossil fuels, but have put ourselves well beyond the point of sustainability. Even with, say, a practically unlimited energy supply we'd bump into the problems of heat dissipation within a few centuries to millennia at present growth rates. We've simply got to stop growing.
As to what's sustainable? Probably on the order of 500m - 2 billion souls if you want any sort of industrialized lifestyle. Hell, even if not, not much more than that.
The next century or two will be very interesting times. Starting likely within a decade or two, possibly less.
Sorry that was probably more hostile then necessary, but when it comes to nuclear power there is very much a "but what about the waste aspect!" used in a manner which implies all other fuel sources don't have very serious problems as well.
The law of unintended consequences has a damned long arm, that's for sure.
Perturbing systems creates long-lived ripple effects. Humans have been tapping into stored carbon equivalent to a few hundred million years of fossil deposits, and ... that's going to have some really long-lived effects. As to what the future holds, my sense is that we're simply not going to have the quantities of free, abundant, and fungible energy we've enjoyed for the past century or so. There are a few people who've arrived at similar conclusions (Dennis Meadows, one of the original Limits to Growth team is among them).
The problem with nuclear waste for me (and others -- Hyman Rickover's criticisms of nuclear energy are revealing) is that the stuff is of such a concern for such a long period of time -- literally longer than written history. How the hell do you create a warning iconography that's going to be comprehensible in 10,000 years, or even 2000? Spoken and written English of even 700 years ago (Geoffrey Chaucer) is barely comprehensible today. And structures to contain it? The very oldest intact buildings we know of are massive stone monuments and even they are both heavily weathered and have long since been plundered (pyramids and other archaeological sites).
The primary problem with oil and coal are simply the quantities we've been consuming of them. If human populations hadn't grown, and they simply substituted for the biomass which was being consumed in their stead prior to the Industrial Revolution, they'd be far less consequential.
I should try figuring out how large a population could be supported at, say, 50% of US rates of energy consumption...
See the way I see it, that's asking the wrong question: who cares what civilization is doing 10,000 years from now, if it's lost sufficient record and technology to comprehend nuclear waste?
Even a language change, if accompanied by a technologically advanced civilization, would remember to change it's signs.
Whereas, it is much more likely that if we don't use nuclear power, we'll create catastrophes that lead to that problem to begin with. I'm much more concerned with what happens over the next 10,000 years then at the end of it.
who cares what civilization is doing 10,000 years from now, if it's lost sufficient record and technology to comprehend nuclear waste?
It's possible to retain a knowledge of what nuclear waste is (at least in a mythic sense of "very bad juju") while 1) losing track of where that waste is and 2) being unable to detect or determine where it is.
Humans have no senses which detect radioactivity (one possibility is that such a sense evolves, though I suspect this is unlikely and would take a very long time). Radiation detectors require some level of technology -- silver nitrite films which fog on exposure, cloud chambers, Geiger counters, exposure badges. It's fairly easy to lose track of where radioactive products are; there's already history of radioactive decay products being incorporated into building materials and otherwise going astray (the Mexican truck hijacking this past week is only the most recent of many civilian-use accidents).
So: a future civilization, which does have a written or oral history of nuclear waste and its hazards, but no means of determining what is radioactive, could definitely have some issues going on. What the outcomes of that might be are an interesting question. It's possible there could be a civilization reboot, or humans could make a long-term slide to obscurity and/or extinction.
This is an important point, so let's be precise here.
The fact that a reactor is fueled by waste doesn't mean it doesn't create waste or have a waste-disposal aspect.
There is nothing in the physics of building nuclear reactors that prevents us from building a reactor that does not leave behind any waste that is either chemically reactive, or even modestly radioactive. No currently implemented reactor designs do that, but it is possible to create one that is both fueled by current reactor waste, and has no waste disposal aspect.
It is unclear if we could ever license such a reactor given the current climate.
There is nothing in the physics of building nuclear reactors that prevents us from building a reactor that does not leave behind any waste
First I've every heard of any such proposal. How exactly would you go about stabilizing every last decay product to the level of background radiation?
Your statement is equivalent to noting that there's nothing in chemistry which prevents us from building coal-fired power plants which capture all CO2 and toxic pollutants (mercury, sulfur, particulates, NOX,, radioactives, etc.) as well. However it's economically and thermodynamically infeasible. Not that emissions haven't been drastically reduced from early designs, but it turns out that that's still not good enough.
Proposed designs go under the heading of 'closed fuel cycle reactors' generally a "fast" reactor (which is using its gamma flux to create new fuel) a reprocessing plant, and the power reactor(s). Such a facility runs "forever" with no radioactive or chemically active byproducts leaving the facility.
Even closed cycle systems generate low level radioactive 'waste' in the sense that things get activated by exposure to radiation. Traditional incineration, like these guys (http://www.nukemgroup.com/fileadmin/pdf/Brochure_Incineratio...) propose, reduces bulk and chemical reactivity, using ionizing radiation from a gamma source (another small reactor like the TRIGA) can move the radioactive byproducts along their decay cycle into short lived isotopes and then inertness.
Nucleotides are the fundamental component of a DNA molecule.
Nuclides are the differentiated nucleuses of the common atomic elements, some of which are regarded as isotopes, of which some isotopes are radioactive
The waste is a vastly exaggerated problem. We've released vastly more uranium and thorium into the atmosphere via burning of coal than we've generated waste from nuclear plants that needs long term storage (the vast majority of nuclear waste by volume has a half life short enough that it is not a storage problem for more than a few decades; only a few percent needs long term storage).
Now, the waste that needs long term storage is more dangerous than the dispersed uranium from coal, but most of the spent fuel can also be reprocessed at least once, and at least India is looking into reprocessing spent fuel multiple times to reduce the amount of high level waste that actually needs to be stored rather than reused.
The resulting storage volume is miniscule, and while it needs to be dealt with, it takes a lot for it to be a significant risk. E.g. plutonium is nasty in some ways - you really don't want to breathe in particulate. But it mostly emits alpha particles, which can be blocked by not much more than cardboard (I remember physics class when our teachers demonstrated with an alpha source, a geiger counter and cardboard...).
Large scale dispersal of plutonium particulate would require a large explosion, so the challenge with plutonium (and uranium) storage is largely to ensure there's no risk of reaching critical mass. But that's "simple" enough to do just by diluting the material enough. There is a security aspect (you don't want people to have an easy way of mining plutonium from waste to produce weapons) but the main storage problem is down to fear.
Most of the gamma emitters have short half lives. I grew up in Norway, and remember the massive fear after Chernobyl relating to Caesium contamination for example (fallout making it into the soil caused Cesium to get picked up in various plants that were eaten by sheep, deer, elks etc. in the highland regions). While it was a public health concern, Caesium-137 has a half-life of "only" 30 years, and a biological half-life in the human body of a few months, and there are plenty of "workarounds" in the case of a major accident (deep ploughing; screening the riskiest food sources; fertilizing with potassium) that helps reduce Caesium uptake until it's radioactivity has sufficiently diminished and/or it has been spread enough to not be a problem any more.
That's not to say we shouldn't take nuclear waste seriously, but it's not a big deal compared to a lot of other hazardous waste we don't think twice about.
It is very disappointing how constricted the field of nuclear research is, as it is a demonstrably zero carbon footprint energy source. I understand the emotion that nuclear power evokes in people, I think the only way to combat the misperceptions is with improving results. I recognize I am a minority in that regard.