Guest essay by Roger Graves
This post deals with the disposal of spent fuel from nuclear power stations, and whether our fears concerning it are justified. You can also read Part 1 and Part 2.
Nuclear fuel typically consists of either uranium dioxide (UO2) or a mixture of UO2 and plutonium dioxide (PuO2), commonly known as MOX (mixed oxide). The uranium can be natural uranium, containing only 0.7% of the fissile uranium-235 isotope, or it can be enriched uranium containing up to 5% of uranium-235. Uranium oxide fuel is only mildly radioactive and can be handled without any special precautions, as the accompanying illustration shows. MOX fuel is somewhat more radioactive, but not dangerously so [1].
However, after both types have been used in a reactor they will contain fission products, many of which are highly radioactive. Spent fuel is known as high-level waste (HLW) and must be handled and disposed of with appropriate care and caution.
After a fuel bundle has been removed from a reactor, it will be both thermally and radioactively hot for a considerable period of time. Spent fuel bundles are normally kept submerged in water for several years after removal from the reactor until the radioactivity has died down and much of the short-lived radioactive fission products have decayed. However, there will still remain a number of longer-lived fission products which can remain dangerously radioactive for thousands of years, and for which a long-term solution must be found.
Radioactivity and Half-Life
The following section is a short primer for those not altogether familiar with the subject of radioactivity. You can skip this if you are familiar with it.
Elements, such as carbon or cobalt or uranium, each have a fixed number of protons in their nuclei, but can have different numbers of neutrons. Versions of the same element, differing only in the number of neutrons in their nuclei, are known as isotopes of that element. Some isotopes are unstable and disintegrate spontaneously, giving off alpha, beta and/or gamma rays in the process. (Alpha rays are high energy helium nuclei, beta rays are high energy electrons, and gamma rays are high energy photons.) For example, cobalt has a stable isotope, cobalt-59, with 27 protons and 32 neutrons in its nucleus, but it also has an unstable isotope, cobalt-60, with 33 neutrons.
Isotopes will be referred to in this article in both the long form, such as cobalt-60 or uranium-235, and in the short form, such as 60Co or 235U.
Unstable atomic nuclei, such as carbon-14 or cobalt-60 or uranium-235, will disintegrate spontaneously at a rate which is specific to that particular isotope. To put it in more mathematical terms, there is a fixed probability that a nucleus of any isotope will undergo radioactive decay in any given period of time. This probability is a constant for any particular isotope but varies from one isotope to another. The level of radioactivity associated with any particular isotope depends on how often decay occurs. The total radiation from a particular sample of that isotope depends on the energy of the particles released during decay, the rate at which decay occurs, and on the sample size, i.e. how many atoms there are available to undergo decay.
The half-life of a particular isotope is the time during which 50% of all the nuclei in a particular sample of that isotope will have undergone radioactive decay. Cobalt-60, for example, has a half-life of 5.3 years, so that if a sample of cobalt-60 is produced in a nuclear reactor, typically for medical purposes, then 5.3 years after it is taken out of the reactor one half of all the nuclei in that sample will have decayed. The total radiation from that sample will be correspondingly halved, since with only half as many cobalt-60 nuclei as there were originally, there will be only half as many nuclear disintegrations per second as there were initially. After another 5.3 years, or 10.6 years altogether, the radioactivity level will have dropped to on quarter of its initial value, and to one eighth after 15.9 years, and so on.
Isotope half-lives vary enormously from one isotope to another. Hydrogen-7 (one proton and six neutrons) has a half-life of 2.3×10-23 seconds, while tellurium-128 has a half-life of 2.2×1024 years, which is about 160 trillion times the age of the universe.
The longer the half-life, the slower the rate at which radioactive decay occurs, and hence the lower the level of radioactivity associated with that isotope. Cobalt-60 has a high radioactivity level because its short half-life means that nuclear disintegrations occur quite rapidly. Uranium-238, in contrast, has a half-life of 4.5 billion years, which is about the age of the Earth. A sample of uranium-238 present when the Earth was first formed would still have half its atoms yet to undergo nuclear disintegration. Cobalt-60 must be handled with extreme care. Uranium-238 can be handled without any radiation-related precautions at all.
Nuclear Fission Products
Almost all civilian nuclear power reactors, i.e. those used to generate electrical energy, use either 235U or 239Pu as a fuel. When either of these two nuclei undergo fission in a reactor, they split into two parts, together with the release of additional neutrons which keep the reaction going, plus energy in the form of heat. The latter, of course, is the whole point of a power reactor. Most fission products are unstable, i.e. they will undergo radioactive decay themselves, and it is these fission products which create the problem in nuclear waste, and for which a long-term disposal method must be sought.
In addition to the fission process, both uranium and plutonium atoms can capture neutrons and be converted into transuranic elements, otherwise known as actinides. These too are radioactive and require long-term disposal.
The chemistry of fission products and actinides is too complex to be discussed at length here. Interested readers are recommended to consult The Chemistry of Nuclear Fuel Waste Disposal by Donald R. Wiles [2].
High-Level Waste Disposal
It is generally agreed that the best way to deal with high-level waste on a long-term basis is to bury it deep underground. The International Panel on Fissile Materials (IPFM), a group of independent nuclear experts from sixteen countries, has stated that “There is general agreement that placing spent nuclear fuel in repositories hundreds of meters below the surface would be safer than indefinite storage of spent fuel on the surface” [3]. However, numerous objections have been raised to this, which can be summarized as the possibilities of accidental dispersal into the biosphere, and accidental unearthing by our distant descendants. The best way to meet these objections is to look at the currently proposed methods for HLW disposal and see how they meet these objections. Before we do this, some basic parameters need to be established.
1. Minimum Isolation Time
First, let us be clear about the purpose of long-term burial. No burial method can be guaranteed to keep the buried material isolated for ever, because ever is a very long time indeed. The purpose instead is to keep the waste isolated for long enough that the radiation levels associated with it will have decreased to a level where any harm associated with it is minimal.
The decay characteristics for HLW from a natural uranium fuelled CANDU reactor [11] are show below [4]. Characteristics for other spent fuel types are broadly similar. Although it will take about a million years until the radioactivity level reaches that of natural uranium, it is not necessary to wait this long for the risk to future generations to become negligible. The human race has coexisted with uranium and other radioactive ores for its entire history, and we do not seem to be any the worse for it. A radiation level ten times that of uranium ore is probably acceptable, considering the fact that by the time the buried material will have resurfaced again it will be very much diluted. The time for this to occur is about 43,000 years, and this can be used as a figure of merit when designing a disposal method.
2. Isolation Process
Second, no long-term disposal method can rely on administrative measures to keep the material safe, such as a fenced-in area patrolled by guards, because while we can perhaps guarantee the maintenance of such measures for a generation or two, beyond that we cannot possibly foresee whether social conditions will permit them to be continued. Consequently, any long-term burial must be done ultimately on a seal-and-forget basis.
3. Water and Oxygen
Third, the two enemies of long-term burial are water and oxygen. Water is important because, without water, there will be no corrosion and any containers used will not corrode. Oxygen is important because, while UO2 is not water-soluble, the UO4— ion is soluble, thereby providing an easy path for water dispersal. The problem of safe, long-term burial therefore devolves largely to one of keeping out both oxygen and water.
Disposal Methods
There are, broadly speaking, three methods proposed or in use for permanent disposal:
- -Deep burial
- Vitrification followed by deep burial
- Ultra-deep boreholes
Deep Burial
Deep burial involves the creation of a geological depository below the level at which atmospheric oxygen can penetrate through solid rock, which is typically 500 metres depth. It is assumed that water can penetrate to this depth, so the burial method must take this into consideration. Burial vaults are designed to have a series of engineered barriers so that if and when one barrier fails, another will come into play.
Deep burial methods have been selected for use in a number of countries, including Finland, Sweden, Britain and Canada. A typical multiple-barrier system which is described here has been adopted, but not yet implemented, by Canada [5].
Canadian reactors use natural uranium in the form of uranium dioxide (UO2) pellets, which are assembled into fuel bundles, 0.5m x 0.1m diameter. Fuel bundles spend about 18 months in a working reactor before they are replaced. There are about 2.6 million used fuel bundles in Canada today, and about 90,000 are added each year.
The Canadian specifications state that the area chosen for the depository must be geologically stable and must provide a minimum of 50 metres of unfractured rock enclosing the depository. The area chosen must have little likelihood that the surrounding rock would ever be exploited as a mineral resource – no recoverable oil, gas, metals or other useful minerals nearby. (This is one reason why old salt mines are not considered suitable for permanent burial because, although they can reasonably be presumed to be water-free for any foreseeable future, they might be re-opened at some future time for salt mining.) Burial would be 500-1000 metres below ground.
Used fuel bundles will be placed into cylindrical stainless steel containers coated with a 3 mm layer of copper for corrosion resistance. The containers are embedded in bentonite, which is a clay that swells on contact with water, thereby providing a self-sealing, low-permeability barrier. (It is commonly used to line the base of landfills to prevent migration of leachate.) The vault is then sealed with a clay- or cement-based backfill. When all vaults are full, the access tunnels and other holes will be sealed, and the land above returned to a pristine condition [6].
In order for the buried waste to become a problem for future generations, the containers must corrode and their contents must be transported back to the surface where they can enter the biosphere. Calculations on the rate at which this could occur indicate that this would be 50,000 years at a conservative minimum. The maximum level of radioactivity at this point would be less than ten times that of the original uranium ore.
Vitrification Followed by Deep Burial
Vitrification can usefully be used in cases where the fuel is reprocessed after use, so that the radioactive fission products can be separated out into a much more compact form than the original fuel bundles.
Reprocessing is only useful where enriched fuel (uranium or MOX) is used, in which the spent fuel still has a significant amount fissile material, and so is worth reprocessing to recover it for further use. In the process of recovery the fission products can be separated out and then mixed with molten glass. The resulting glass blocks are very much more corrosion resistant than the original fuel bundles. They can then be permanently disposed of by deep burial in a manner similar to that described above. Although long-term calculations are subject to many variables, the indications are that vitrified HLW would take hundreds of thousands of years before its radioactive burden was released to the biosphere [7].
Ultra-Deep Boreholes
The US is actively examining a method of burial in which vertical shafts up to 5 km deep and a metre in diameter are bored into the Earth’s surface [8]. Nuclear waste in strong steel containers would be lowered into crystalline rock in the lower 1 to 2 km of the hole, and the remaining 3-4 km would then be steel-lined and filled with layers of sealing materials such as bentonite, asphalt, concrete and crushed rock.
Under some variants of this plan, the waste would still be radioactively hot when inserted into the borehole, and the heat produced would melt the surrounding rock. When it cooled after a period of years, the waste would be completely entombed in the rock. Lest anyone should think in terms of an underground nuclear explosion as a result, the geometries involved make this quite impossible.
One problem with this scheme is that current technology only permits boreholes of less than 50 cm diameter to be bored to this depth, so nuclear waste would have to be repacked before it could be inserted. However, it is a reasonable expectation that, were this method to be fully implemented, the required one-metre boring technology could be developed.
An advantage of this method of disposal is that it would be very sparing in land use. It is estimated that the entire US nuclear waste stockpile would require no more than 800 boreholes, which could be situated on an area of no more than a few square kilometres. Filled and capped boreholes could be covered over and the land returned to a pristine condition.
Problems with Finding a Depository Site
The physical properties required of a permanent disposal site are well-defined, and such sites can reasonably easily be located. The social properties can be more problematic. Any site selected must be acceptable to the local inhabitants, acceptable to nearby communities, and acceptable to the wider public.
It is an undeniable fact that there is a deep-seated fear of nuclear energy in our society. Part of this presumably stems from the use of nuclear weapons in World War II and their continuing deployment to this day. However, part of it must be ascribed to what can only be described as hysterical overreaction by journalists and public intellectuals to any nuclear-related accident. Isaac Asimov, a normally level-headed science fiction writer, based some of his books around a future uninhabitable, intensely radioactive Earth arising from the Three Mile Island accident (which actually hurt no-one and released only miniscule amounts of radiation [9]). The claim by some public intellectuals after Fukushima that the whole western seaboard of North America would have to be evacuated arose from the same fount of baseless hysteria.
Nonetheless, any attempt to impose a nuclear waste disposal facility on a particular location by government fiat is going to meet with resistance from local inhabitants unless the concept is explained very carefully in advance. The first attempt by the US to drill an experimental deep borehole, in Pierce County, North Dakota, failed when local officials first heard of the project through the media [10], which may well be described as a textbook example of how not to get the local populace on your side.
Disposal sites are most likely to be located in remote, sparsely populated areas where employment opportunities are few and far between. Any disposal site, once opened, is likely to stay in operation for many years before it is finally sealed off, thereby providing well-paid employment for local people. This, together with a completely honest and open description of what the disposal facility is and is designed to do, has a much better chance of getting approval from the local population.
Summary
High-level nuclear waste is a problem but not an insoluble one. Our ancestors have had other problems disposing of toxic waste in the past, and have come up with solutions for it. One advantage of HLW is that it will gradually become less dangerous as time goes by, unlike, say, arsenic waste from mining which will remain toxic no matter how old it is. A properly designed nuclear disposal facility will be capable of isolating high-level waste until it is no longer a threat.
Acknowledgement
My thanks go to Don Wiles, emeritus professor of radiochemistry at Carleton University, Ottawa, Canada for some of the material used here and for his much appreciated advice and comments.
Roger Graves is a physicist and risk management specialist who, much to his chagrin, is not associated with big nuclear, big oil, or big anything else.
References
1. https://eclass.duth.gr/modules/document/file.php/TMA368/paper1.pdf
3. http://thebulletin.org/managing-nuclear-spent-fuel-policy-lessons-10-country-study
4. https://www.nwmo.ca/en/Canadas-Plan/Canadas-Used-Nuclear-Fuel/Radiation-Risk-and-Safety
5. https://www.nwmo.ca/en/A-Safe-Approach/Facilities/Deep-Geological-Repository/Multiple-Barrier-System
7. http://www.nwtrb.gov/facts/Vitrified_HLW.pdf
8. https://en.wikipedia.org/wiki/Deep_borehole_disposal
10. http://www.sciencemag.org/news/2016/09/protests-spur-rethink-deep-borehole-test-nuclear-waste
11. https://en.wikipedia.org/wiki/CANDU_reactor
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We need to reprocess nuclear waste as the French have done and recover the 97% unspent fuel. The Molten salt Reactor will be coming online in the next seven years and the design fissions fuel much more efficiently. One line chemistry removes the Xenon allowing a more through consumption of the fuel and secondary product breakdow. Due to the MSR’s low-pressure safety, they should cost 1/3 of a LWR due to no Pressure Dome, no 70-150 atmosphere plumbing or triple redundant cooling/power systems as they fail to a cold state with a freeze plug gravity drain tank system. http://www.egeneration.org
It might be less than seven, perhaps three to five if Terrestrial Energy
is to be believed. Acccording to them, their IMSR would
be able to burn conventional reactor waste down to
to non-radiosctive ash. Waste disposal? What waste
disposal?
Minor error: gamma rays are NOT protons, they are “photons in the highest observed range of photon energy.” (Wikipedia) As far as I am aware there is no type of radioactivity involving protons, other than the two bound to two neutrons in an alpha particle.
I also have “An idiots Brief Guide to The Discovery and Uses of Radiation.” Also on Amazon, and cheap at $10, for those few intellectually challenged commenters on this site who haven’t got a clue about radiation. It also has a section on Health Effects of Radiation, and about the LNT hypothesis, for those with a lot more nouse (if you know that word).
https://www.amazon.com/Idiots-Brief-Guide-Discovery-Radiation/dp/1508674817/ref=asap_bc?ie=UTF8
Read and enjoy.
“Nuclear Wastelands
A Global Guide to Nuclear Weapons Production and Its Health and Environmental Effects”….
https://books.google.com.au/books?id=0oa1vikB3KwC&printsec=frontcover&dq=Nuclear+Wastelands:+A+Global+Guide+to+Nuclear+Weapons&hl=en&sa=X&ved=0ahUKEwit1OvW__XSAhVIKGMKHRYXBwAQ6AEIGzAA
Nouse: https://www.collinsdictionary.com/us/dictionary/english/nouse
A device which enables the user of a computer to direct the cursor around the screen by means of nose movements.
Collins English Dictionary. Copyright © HarperCollins Publishers
Waste from conventional nuclear power plant is fuel for for a fast neutron reactor and the true waste is only dangerous for 300~500 years.
https://www.scientificamerican.com/article/smarter-use-of-nuclear-waste/
http://www.nationalcenter.org/NuclearFastReactorsSA1205.pdf
The US developed an ‘integral’ transuranic waste burning fast reactor, with a walk away safe unpressurized reactor vessel. The fuel was reprocessed by simple electrowinning on site, and re-used, whilst the fission products were removed and made into an inert alloy. The fuel had no proliferation potential. Very high burnups were possible – 10% or more (they found a simple cure for the expanding metal fuel problem).. The reactor was walk away safe, and could ride out complete abrupt auxilliary power failure. Fission products decay in around 500 years, not a long time compared to the 200k+ years for problematic transuranics (all burned as fuel).
Mr John Kerry pulled funding under Clinton.
The engineers, chemists an physicists involved wrote a book accessible to the educated layman describing the technology that they had developed in detail, for the curious, here is a pdf:
http://www.thesciencecouncil.com/pdfs/PlentifulEnergy.pdf
A hint of the fuel potential of waste thermal fuel can be gained by watching the Canadian Uni seminar (considers CANDU waste, but the arguments has broader validity):
Fast-neutron reactors: A wiser solution to spent nuclear fuel?
The cost of deep geological disposal is staggering. It should be included when pricing up thermal nuclear plants IMO.
If you want someone to read your essay, Roger Graves has just shown how it is done.
It was my pleasure.
This book cover the LNT model quite well.
Radiation and Reason: The Impact of Science on a Culture
https://www.amazon.com/gp/search?index=books&linkCode=qs&keywords=9780956275615
No mention anywhere about the volume of low-level radioactive waste from artificial isotopes used in medicine, and high-level waste from isotopes used as neutron sources in oil well logging, “X-raying” of steel structures to look at the integrity of welds, etc. etc. And let’s not forget the smoke detectors that all of us should have in our homes IIRC they contain a few micrograms of 241Am, but there are lots and lots of them. None of these have anything to do with nuclear power, but they all generate radioactive waste.
Many of us are old enough to remember watches with luminous “radium” dials. I still have an altimeter from a P51 Mustang. It has a “radium” dial with really big figures, and when I started working in uranium exploration and had a scintillometer, I realised how very radioactive it was, and it had better be stored outdoors. Some of us remember gas lighting in houses. The gas “mantles” are made of thorium oxide, and they were quite strongly radioactive. Not many houses with gas lighting any more, but you still have mantles in Coleman lamps and Tilley lamps and Primus lamps. Somewhere between 1970 and 1990, they manged to produce refined, non-radioactive ThO2.
My point is, as an advanced industrial society, we use a shed-load of radioactive isotopes for all kinds of things, and I’ve probably only mentioned a fraction of them. They all have to be disposed of, but do we hear a whimper from the green set about their dangers?
Smart Rock,
They do not HAVE to be disposed of. We live every day and every night of our allocated 24/7 in the presence of natural radioactivity. Natural radioactivity is just as harmful as that created with the help of mankind. It is a fair assumption that radioactivity needs to be managed only when it adds an extra, largish burden to the natural amount. Thus, if one spread that Mustang dial over a large enough area, it would not be detectable above the natural background and so would not need management. However, before it was spread, it could be a “point source” type of danger, depending on the weight of radium used. But this is all old knowledge and routine procedures today have learned from the observations of old.
You point to a difficulty that others have also mentioned before. That is a success story producing problems of the unintended consequences type. The early instruments for detecting radioactivity were too sensitive, they were too successful. They were also fairly easy for the public to access and use. Over the decades, all sorts of materials, like bananas for instance, were found to be anomalous in radioactivity. While this type of information was probably already known to science, or could be predicted, it made a talking point that like all talking points, had the capacity to be distorted and used for anti- nuclear propaganda. If the early Geiger counters had not been so damned sensitive, we could have avoided a huge quantity of misinformation, be it accidental or by design.
Geoff
Most radioactive medical waste has very short half-lives — minutes, hours or days. After 10 half lives in many cases it is no longer considered radioactive. Some are such low level that they can be disposed of down the drain — disposal by dilution.
It used to be that there were no regulations on radioactive human waste — just throw it out, flush it or burn it. No more.
In my lab we were able to dispose of radioactive reagents by letting them evaporate under a fume hood — disposal by dilution — but the reagent vapors were considered chemical pollutants so we had to let them sit for 10 half lives then treat them as chemical waste.
Radioactive research animals were double bagged, sealed in yellow 55 gallon steel drums and trucked to Hanford.
There are many interesting stories in nuclear medicine. Not all of them are funny.
Yes you do here a lot about the dangers of that stuff, if you listen in the right place.
Ex RAF bases may have sites with substantial contamination from exactly the type of dial you describe.
I’ll add one more use of nuclear material – a common UK telephone model, the ‘trimphone’ had a luminous dial surround provided I believe by radioactive tritium.
Griff
Luminous dials have a longer history of contaminating humans. In WW1 dials of military aircraft were painted with a luminous paint based on alpha activity of 226Ra. Only a few years later cases of osteosarcoma began to appear among the “dial painters”, but several more years would pass before radioactive substances like radium – initially even considered as a health tonic – were recognised as carcinogenic.
Now the dial painters like WW1 veterans have only just died out. They represent still the best source of epidemiological data on bone carcinogenesis from alpha emitting bone-seeking radionuclides. They show very clearly a threshold: 10 Gray of cumulative dose to the endosteal bone lining cells. Only above 10 Gy did osteosarcoma start to go into excess. Interestingly leukaemia was completely absent as an elevated risk. The dose distribution was wrong – the haemopoietic stem cells associated with leukemogenesis are deep on the central marrow spaces, while the short (20-30 micron) ranges of alpha particles failed to reach them, damaging instead the peripheral bone lining cells and causing osteosarcoma.
This is one of many lines of radiobiological evidence that firmly refutes the LNT linear no threshold hypothesis of radiation carcinogenesis.
There are plenty of places on earth where above ground storage is very feasible. In the U.S. for example, Skull Valley, Utah comes to mind. The only real problem would be security, what with all the nut job radicals who’d like to get a hold of the waste for dirty bombs.
I was intrigued by this…
“Used fuel bundles will be placed into cylindrical stainless steel containers coated with a 3 mm layer of copper for corrosion resistance.”
Would the container suffer corrosion of dissimilar metals?
Don’t feel competent to make an informed decision on nuclear but have seen a nuclear bubble come and go. Mid to late 1970’s TVA undertook a very large scale nuclear electricity generation program. Billions in bonds were sold and construction was begun at several sites. Rapidly increasing electricity bills were a concern for all consumers but not sure that nuclear was the reason. The massive capital investment raised average wages in our area and resulted in the Dairy Queen becoming the Nuclear Drive In. After a few years of construction many of the sites were abandoned and coal plants were expanded or built. Apparently demand did not meet projections. The debt remained and may actually still be getting paid by the usual victims i.e. ratepayers. Who knows what really happened? The Dairy Queen is back but sits in the shadow of a gigantic containment tower with no reactor under it. Pure farce.
I recall the fear perpetuated by the British media in 1984 regarding nuclear waste, so this test was set up.
The locomotive weighs about 110 tons and each of the cars about 10 tons each, and I think the speed at impact was about 100 mph.
Interesting article which suggests that solar energy production employes more people than coal, gas and oil combined. There may be posters who are very unhappy at this and think it a waste of resources, but that employment is a lot of votes.
Nuclear production employs 68,000 and solar 373,000. I suppose one of the reasons is that local engineers can install solar power on your rooftop with great success, but nuclear takes a bit more skill.
Fossil fuel employs 187,000, wind generation employs 101, 000.
These are US figures by the way, so the difference in Europe would be even more stark.
https://www.forbes.com/sites/niallmccarthy/2017/01/25/u-s-solar-energy-employs-more-people-than-oil-coal-and-gas-combined-infographic/?utm_source=FBPAGE&utm_medium=social&utm_content=841020857&utm_campaign=sprinklrForbesMainFB#5a4831b82800
That’s Govn’t for ya. Employ people to dig holes, quickly followed by more people to fill them in again. Works every time, until it doesn’t when OPM runs out.
Gareth,
“Interesting articles” rarely “suggest”. For hard science, articles of interest produce hard figures and hard deductions consistent with the data gathered.
The number of votes from readers is immaterial. I am one of those who considers make-work projects to be not needed, not wanted and a drain on more productive work. Since I was first involved in the costing of national electricity systems in the 1970s, it has been well known that large scale solar and wind would never compete with fossil fuel electricity for other than small boutique applications. Part of the reason was the more numerous labour force per useful MW produced, part was because of energy density limitations, other reasons also.
It is sad to have to pay so much money for wind and solar to show that the 1970s figures, especially their relativity over different generation types, has remained fundamentally the same. How much more money will be wasted to prove the busted flush predicted in the 1970s?
It is all so stupid.
Geoff.
You may not have noticed that Nuclear power is also heavily subsidised. as are most energy sources.Is that ok as long as the source is not renewable?
The grammar used in my post is typical of the way studies are addressed in the UK. We don’r say “this research says this or that”, we say “This study suggests that” this is because we don’t believe any science or research is “case closed and science settled” though I accept you may feel that way against energy sources you fundamentally disagree with.
The main problem with domestically generated solar power is that once installed, it makes no further profit for anyone except the householder. That of course is completely unacceptable. Essential services like energy must always be seen as lucrative sources of profit for major power producers, otherwise, why bother to produce it? . ( Sarc//off)
Typical leftist.
Any tax rate less than 100% is a subsidy.
Every electrician who once in a while screws a panel onto a roof is part of the 373 000; his wife, who does the book-keeping every friday, too.
That is how “clean-energy” jobs are created all over the world.
Milton Friedman > Quotes > Quotable Quote
Oh, I thought you were trying to build a canal. If it’s jobs you want, then you should give these workers spoons, not shovels. [Reply to the government bureaucrat of one Asian country who told him that, reason why there were workers with shovels instead of modern tractors and earth movers at a worksite of a new canal, was that: “You don’t understand. This is a jobs program.”
Gareth, I am taking your numbers for granted. EIA data (USA, January 2017) bundles wind and solar as “other renewables”. 474,000 jobs in wind+solar generated 29.4 TWh of electricity. 68,000 jobs in nuclear generated 73.1 TWh. 187,000 jobs in fossil fuels generated 203.4 TWh. Please compare the efficiency of these jobs.
Could we please, please dispose of the notion that power reactors and reprocessing are a weapons proliferation risk?
Any government wanting nuclear weapons will get them regardless of a civilian power program or not. Look up how Stalin got the plutonium for his first bomb.
Leave the rods in the reactor too long and you have a nasty isotope separation problem. Pu 239 and Pu 240 are more difficult than U235 and U 238. Look at the differences in atomic mass.
Well, originally, that is exactly what the reactors were built for. Making weapons grade fissile material.
Indeed.
Much UK nuclear plant set up with that in mind.
Speaking from a rather ignorant position, may I ask why it is that we assume categorically that future societies will be ignorant and therefore incapable of dealing with nuclear waste? We assume that it will forever be impossible to use any of this stuff, whatever it may be now or in the future.
Also, I always understood that the longer the half life of a radioactive substance the less dangerous it is and the less need to go to extraordinary lengths to isolate it for vast periods when it will be virtually harmless.
“Macspee March 27, 2017 at 2:05 am
Also, I always understood that the longer the half life of a radioactive substance the less dangerous it is and the less need to go to extraordinary lengths to isolate it for vast periods when it will be virtually harmless.”
A common misunderstanding about the half-life of radioactive materials.
It’s not that we assume that future societies will be ignorant, it’s that we have to assume that it is a possibility and plan for it.
Or we could wrap the nuclear waste in photovoltaic panels tuned to capture the specific wavelength of radiation emitted by the waste, and use the electricity produced to run the floodlights and electric fences keeping the hippies out.
High energy photons heck. That’s what solar panels are designed to collect and turn into electricity.
Alpha and Beta particles are blocked by water and other solids. Easy to control. It’s the gamma radiation photons that are the bug.
Solar panels as nuclear waste containment are the solution with a bonus of extra usable electricity.
After the half life is over the light emitting diode winks out, signaling it’s safe for handling.
“Deep burial methods have been selected for use in a number of countries, including Finland, Sweden, Britain and Canada2
the UK is no nearer getting even a site for this than it was 50 years ago.
Is anyone actually building a deep repository?
In Finland we have a company called Posiva drilling a repository for HRW. Planning started 1980, drilling is ongoing and its ready 2020. The cost of operation is collected during last decades, the cost is added in the price of electricity produced using Uranium.
http://www.posiva.fi/en/final_disposal/general_time_schedule_for_final_disposal#.WNnVKZFpuhA
“However, there will still remain a number of longer-lived fission products which can remain dangerously radioactive for thousands of years, and for which a long-term solution must be found.”
Not true!!!!
The whole spent nuclear fuel issue is based on a false assumption. Spent fuel is dangerous for about 300 years.
For something to be dangerous, people would be hurt if precautions are not taken. At 300 years radiation from spent fuel would not be hurt people.
Water is dangerous. Many drown every year. About 17 liters of water, can result in death if taken in one sitting. There have been cases where this has happened.
Eating is dangerous. I once was taking a date out to dinner. We had been dating long enough for me to know her parent were dead but I did not know the details. Going to the steakhouse where her father choked to death was a mistake. Chinese it is! While in China, two of us had food allergies. Not being able to read the menu, was a challenge. Duck it is!
The point is we all have experience with loved ones being hurt or killed. My brother in law was killed by a drunk driver. We have all spent anxious hours in the emergency rooms second guessing what we could have done better to keep our children from being hurt.
None of the readers here have any experience being hurt by spent nuclear fuel. The question of what to do with spent nuclear is a result of manufactured fear by the anti-nuke lobby. As this essay demonstrates, there are many answers providing good solutions.
I’m not an engineer but this is what I’ve gleaned from various sources.
When it comes to waste, advantage LFTR.
LWR 1 GW Year – 35 tons of spent fuel – 93% unused fuel plus transuranics and fission products.
Also 215 tons of depleted uranium left over from enrichment.
LFTR 1 GW Year – ~ 1 ton of fission products only. Does not reject fuel to the waste stream and except
for Pu-238 does not produce transuranics.
Uses thorium (an unwanted waste product from phosphate and rare earth mining) so no mining or enrichment required.
Fission products quickly decay to stability.
422 isotopes at shutdown – about 1 ton.
56 isotopes at 1 week.
24 isotopes at 1 year.
17 isotopes at 10 years.
12 isotopes at 100 years.
8 isotopes at 300 years – about 250 Lbs. – listed below.
Isotope Half-life
Se-79 Selenium 327 K Yrs.
Zr-93 Zirconium 1.5 M Yrs.
Tc-99 Technetium 213 K Yrs.
Pd-107 Palladium 6.5 M Yrs.
Sn-126 Tin 100 K Yrs.
I-129 Iodine 15.6 M Yrs.
Cs-135 Cesium 2.3 M Yrs.
Sm-151 Samarium 88.7 Yrs.
These 8 isotopes are 1 neutron away from stability.
So if one had a neutron source, like say a reactor, it might be possible to transmute these to stable isotopes leaving zero long term radioactive waste.
A great idea. It should be easy to extract those 8 elements from a spent fuel. There will be probably more than one isotope of each, and an irradiation by neutrons may create new radioactive isotopes. Definitely worth more development.
One of the best books on this general subject of the history of radiation, ever written, in my opinion, and I go back it often enough, is the one by Marshall Brucer. A Chronology of Nuclear Medicine.
If you follow your burial concept, you are depriving centuries of humans in the future of nuclear power. Why on Earth should we be so inconsiderate? Develop instead safe methods of utilizing all the energy in uranium and thorium so mankind can have a long and productive future, millennia, not just centuries. This means reprocessing and reuse.
The fact is — as demonstrated in these posts — that here are many ways of safely disposing radioactive waste and that the only element missing is the will (political or otherwise) to adopt Nuclear Powered Energy and ‘get on with it’, instead of finding (and relying on) supposedly every reason “why Not” … such as — in this instance: “Oh dear, we can’t dispose of the radioactive waste.”
If man can get to the moon, we sure can find a way to dispose of nuclear wastes — if we have the will to find the means. All the whingeing nay-sayers are probably exposed to more radiation in aggeregate by visitng their basements, flying at high altitude, having x-rays, etc., than ever they would get if one truck passes by, laden with a massive containment vessel containing spent fuel-rods once a year.
Anyone got any figures on this?
When I first read, many years ago, about the development of the Molten Salt Reactor by Weinberg, I was horrified by the fact it was another of those ‘best of the best’ ideas defeated by our “need” to develop plutonium producing reactors to fuel the war effort. But the fact that it can be net or negative on long-lived radioactive products is a real deal changer. Stupidly, only the Indians and China are developing on a crash basis this USA technology, stand on the shoulders of Weinberg’s crews work.
And yes, a properly equipped MSR can CONSUME our existing waste.,
Again
I say
I have heard that the problem in Chernobyl has not yet been resolved.
They have to re-encapsulate the whole plant again because the radiation is increasing.
Apparently this is so expensive that the Ukraine government cannot pay for it. So they are now asking the EU to pay for it…
Friends, can we leave it there? There is no future in nuclear energy as the safety measures including the disposal of nuclear waste are cost prohibitive.
Nothing to do with me being right, left or centre, politically speaking.
Anyone foolish enough to dump water on very hot graphite (ever heard of water gas?) deserves to be sent back to high school chemistry. Unfortunately the government made the decision,
Link, please.
In [ http://www.world-nuclear.org/information-library/safety-and-security/safety-of-plants/chernobyl-accident.aspx ], the statement ” There is some dispute among experts about the character of this second explosion, but it is likely to have been caused by the production of hydrogen from zirconium-steam reactions.” was a later addition to the discussion. Shortly after the event occurred a discussion I saw (no link) referred to a hydrogen explosion that occurred because of attempts to fight the graphite fire with water. This reference points out that the cooling system rupture provided plenty of water for such a hydrogen promoted explosion which would be necessary to explain the one kilometer high debris ejection. It does not seem likely that a simple hot graphite-heated thermal steam ejection could be provide the immense energy required.
Even according to your source, the steam come from ruptured primary and secondary cooling circuits, and the explosions happened within two seconds. I don’t really believe that the Soviet government made a decision within two seconds. Actually, the Chernobyl management maintained for hours that the reactor was intact. There is a readable account of the events by Zhores Medvedev, available at Amazon.
henryp. There is nothing else but nuclear as yet after fossil fuels are gone. The number of deaths at nuclear electrical generating plants were fewer than a dozen in 50yrs until Chernobyl which was designed with no safety features by the Soviets. Today, it is now a game park. Early deformed animals were eaten up by healthy wolves and other predators that ultimately came to the “park”. You can google 4000 deaths or more but in reality there were only about 70. Go to Wikipedia – you will trust that re deaths caused by Nuclear electrical plants. Did you know that only one person died in the most nuclear electrified society in the world? France. Some governments are getting the French to design their nuclear plants. Since 1980s when Chernobyl was built, we have had a revolution in electronics, detection and controls. Anyway, rant and rail but there is nothing else so far on the horizon to replace fossil fuels which are not going to last.I’m sure at this late date you are somewhat disappointed in renewables (except for hydro, which you may not like either).
Gary
I have nothing against Hydro, it would be on top of my list
next is gas or oil
and if there is nothing else: coal [ remove sulfurous gases]
This can apparently keep us for ages.
next we have wind,
a good idea is to have wind pump water into a big reservoir [lake] which can be released to make [hydro] electricity so you realize energy when you actually need it….They are going to try this concept in Belgium soon…I hope…
Then we have solar, in various forms but it is lower on my list of importance due to costs as do tidal forces.
Last on my list would be nuclear, simply because it is too expensive because of all the [too] apparent risk factors.
[btw. I have a done some extensive research to find that there is no man made global warming, so that debate should not determine your decisions.]
All the best
Henry
Good article and interesting comments.
I don’t know what the half life of an idea is, but in ten years I may not be around. So, I’ll add to the proposals to drop radioactive waste into the salt chuck, as we say on the Wet Coast.
Put it in old shipping containers, sheath it in lead and then glass it. For shipping to the Mid-Atlantic rift. It is some 5000 miles long. Drop it. Any threat is gone.
In the meantime, I have an old water dispenser made out clay. Called a “Revigorator” the clay included some “Radium Ore” as printed on the lid. Inside, I’ve kept an article from the August 1, 1990, Wall Street Journal. The headline is “The Radium Water Worked Fine Until His Jaw Came Off”
It starts with “In 1927, a steel mogul and socialite…tumbled from the top berth of his private Pullman car.”
A patent medicine called Radithor was touted as a cure for more than 150 maladies.
The wealthy young man convinced himself that it was invigorating and took it for long enough such that his “whole upper jaw, excepting two front teeth, and most of his lower jaw had been removed.”
Before he died of radiation poisoning, he had complained to his doctor that he had lost “that toned up feeling.”
I guess that this reference will drive the chronically superstitious up the wall. but enter the comment confident that such posters do not frequent this site.
subtle2 I am an old geezer also and during my life the hype of the dangers of radioactivity have amused me greatly. The ending of ww11 by dropping two dirty atomic bombs on Nagisaki and Hiroshima should have caused by todays standards a thousand years of toxic zones. Strangely the people rebuilt these cities and those close to the blast zone that survived got on with their lives. Recently i saw a little snippet of a woman that lived into her 90ties that was just outside the blast zone in one of these cities. Those that survived seemed to have normal lives. Methinks the hype about exposure to radiation is a little bit exaggerated and exposure to the sun in too much quantity is as dangerous.
Meanwhile in Finland…
http://www.posiva.fi/en
we have companies and factories dealing with nuclear waste?
one person’s s..t is another bread>?
sorry
that last sentence should read:
one person’s s..t is another person’s bread?