Radioactive Wolves.

[Warren Dew]

Zilla, on your question about how many reactors and how many bombs.

The World Nuclear Association gives about 430 reactors producing a total of about 3700 GW electricity in October 2011. Multiply by roughly 3 to get ~10 TW thermal effect.

Stockpiles are harder, and there are many estimates. Here is one historical listing http://www.johnstonsarchive.net/nuclear/nucstock-0.html, giving peaks of about 70,000 warheads, and 27,000 Mt, in the 1970's. Another estimate I found was 5000 Mt today. If we (roughly) estimate half of that to be fusion energy, those numbers need to be halved for fission content.

If we calculate from here, it would take about 1.5 years for all power plants to produce the energy of the fission part of the peak total weapons stockpile and about 4 months to match todays stockpile. If we consider that the medium age for the fuel in a reactor is about 2 years, we can estimate that the amount of long lived fission products in all reactors today is of the same order of magnitude as the long lived fission products that theoretically could have been released in a nuclear holocaust during the crazy years, and clearly above what is available today.

But then we have to add all the short lived nuclides from the weapons and activation products from both, so that is not the full picture. And of course, you have to put a nuke (or another big bomb) on a power plant to get it to release all of its content.

Hope I didn't make any bad mistakes, calculating with that many zeros is always a challenge -maybe Jim's 11 y students could check my calculations

Well, I'm lazy and I'll just do one case. Taking your 2500 MT of fission energy in current nuclear warheads, which looks reasonable, that's 2500 MT x 4.2 PJ/MT = 10500 PJ or 10,500,000 TJ = 10,500,000 TWs. With 10 TW of thermal power, that would take 1,050,000 seconds to produce if all the reactors were running. 1,050,000s ~= 300h ~= 13 days. If I'm right, you lost one factor of 10 there; the nuclear power plants of the world produce as many fission products every couple of weeks as the entire world's arsenal of nuclear weapons, and every quarter or so as much as the largest arsenal the world has had.

That would say the total amount of medium to long lived fission products in the world's nuclear plants is perhaps 5 times the maximum that could ever have been released in a nuclear holocaust, and around 25 times what a nuclear holocaust could release today.

I agree with you that it's unlikely that we'd see all of that released at once, either for the reactors or for the bombs, but in combination with the original video, it does illustrate that the amounts of energy and fission products we're talking about are not unimaginable.

[MiM]

Zilla, on your question about how many reactors and how many bombs.

The World Nuclear Association gives about 430 reactors producing a total of about 3700 GW electricity in October 2011. Multiply by roughly 3 to get ~10 TW thermal effect.

Stockpiles are harder, and there are many estimates. Here is one historical listing http://www.johnstonsarchive.net/nuclear/nucstock-0.html, giving peaks of about 70,000 warheads, and 27,000 Mt, in the 1970's. Another estimate I found was 5000 Mt today. If we (roughly) estimate half of that to be fusion energy, those numbers need to be halved for fission content.

If we calculate from here, it would take about 1.5 years for all power plants to produce the energy of the fission part of the peak total weapons stockpile and about 4 months to match todays stockpile. If we consider that the medium age for the fuel in a reactor is about 2 years, we can estimate that the amount of long lived fission products in all reactors today is of the same order of magnitude as the long lived fission products that theoretically could have been released in a nuclear holocaust during the crazy years, and clearly above what is available today.

But then we have to add all the short lived nuclides from the weapons and activation products from both, so that is not the full picture. And of course, you have to put a nuke (or another big bomb) on a power plant to get it to release all of its content.

Hope I didn't make any bad mistakes, calculating with that many zeros is always a challenge -maybe Jim's 11 y students could check my calculations

Well, I'm lazy and I'll just do one case. Taking your 2500 MT of fission energy in current nuclear warheads, which looks reasonable, that's 2500 MT x 4.2 PJ/MT = 10500 PJ or 10,500,000 TJ = 10,500,000 TWs. With 10 TW of thermal power, that would take 1,050,000 seconds to produce if all the reactors were running. 1,050,000s ~= 300h ~= 13 days. If I'm right, you lost one factor of 10 there; the nuclear power plants of the world produce as many fission products every couple of weeks as the entire world's arsenal of nuclear weapons, and every quarter or so as much as the largest arsenal the world has had.

That would say the total amount of medium to long lived fission products in the world's nuclear plants is perhaps 5 times the maximum that could ever have been released in a nuclear holocaust, and around 25 times what a nuclear holocaust could release today.

I agree with you that it's unlikely that we'd see all of that released at once, either for the reactors or for the bombs, but in combination with the original video, it does illustrate that the amounts of energy and fission products we're talking about are not unimaginable.

Thank you for checking Warren. Yes, I made a mistake, but the mistake was not in my final calculations, but in this:

The World Nuclear Association gives about 430 reactors producing a total of about 3700 GW electricity in October 2011. Multiply by roughly 3 to get ~10 TW thermal effect.

The actual number given by the association is 368,467 MWe (http://www.world-nuclear.org/info/reactors.html), which is about 370GWe, not 3700GWe, so the thermal effect should be 1TW, not 10 TW (from which I mislead you to start). Which leads to that my final result was right after all. Sorry for that confusion.

[JimC]

There are very few if any operational reactors that use plutonium.

Actually, almost every commercial reactor uses plutonium. This is because commercial reactors generally start with low enriched uranium, which is typically only 2-3% fissionable U235. The rest of the uranium is largely U238, some of which absorbs neutrons and transmutes to fissionable Pu239 which then undergoes fission. Over the usage life of a typical commercial reactor core, approximately the same amount of power is extracted from plutonium fission as from uranium fission.

Honestly, your post makes it sounds like you know very little about nuclear engineering. You might want to do some research before posting on the topic.

True, although I'm not sure it is quite a half - around one third was what I had heard. However, I took Schneibster's point to be about the use of Pu239 as a primary fuel, derived from fast breeder reactors. The fashion for those never really took off, given the travails of transporting highly radioactive Plutonium, which is also a perfect target for a terrorist group...

You bet that breeder reactors, that produce more Pu than they are fed would have taken off if the arms race hadn't dropped off, and with it the need for that element. Plutonium is fine fuel, but since it doesn't exist naturally, obtaining it relies on operations that use other fuels, and now that the use for it is not so great, we can rely entirely on primary reactors using mainly LEU.

Also, the argument from the nuclear reactor boosters was that U235 is a finite resource; making Pu239 was seen as a way of greatly extending the future of fission reactors...

Personally, roll on workable fusion...

[Cormac]

It turns out that DNA has mechanisms for dealing with mutations, able to modify the mutation rate not only for too much damage, but too little. We have evolved to evolve, and because of this we have automatic machinery for detecting and correcting errors and suppressing and exciting mutations that writers in the 1950s had no idea existed. That's why radioactive areas like that around Chernobyl aren't full of mutant slime monsters. Of course, simply being able to evolve in such an environment is no guarantee against slow developing chronic conditions due to radiation exposure, but DNA never cares about the experiences of individuals.

Sure. Tell that to the tragic David Banner.

[JimC]

It turns out that DNA has mechanisms for dealing with mutations, able to modify the mutation rate not only for too much damage, but too little. We have evolved to evolve, and because of this we have automatic machinery for detecting and correcting errors and suppressing and exciting mutations that writers in the 1950s had no idea existed. That's why radioactive areas like that around Chernobyl aren't full of mutant slime monsters. Of course, simply being able to evolve in such an environment is no guarantee against slow developing chronic conditions due to radiation exposure, but DNA never cares about the experiences of individuals.

Sure. Tell that to the tragic David Banner.

[Schneibster]

Also, the argument from the nuclear reactor boosters was that U235 is a finite resource; making Pu239 was seen as a way of greatly extending the future of fission reactors...

Keep in mind that estimates of limited uranium are based only on known reserves, whereas we know for certain there are undiscovered sources at least as large as what we've found so far.

Personally, roll on workable fusion...

They are currently trying to turn that trick five different ways:

"Cold" fusion, probably the third least likely to yield net energy output
EMC2, Bussard's IEC device, quite likely to work but proceeding very carefully
Lawrenceville Plasma Physics' Dense Plasma Focus device, moving along with funding from overseas
ITER, which at last report had a Deputy Assistant Director-General's Assistant Deputy Assistant something-or-other and appeared to be suffering from advanced bureucratitis
Electron Power Systems, dark horse, likely down for the count and starting to look kinda cranky

I think the Plasmak is dead.

[JimC]

Also, the argument from the nuclear reactor boosters was that U235 is a finite resource; making Pu239 was seen as a way of greatly extending the future of fission reactors...

Keep in mind that estimates of limited uranium are based only on known reserves, whereas we know for certain there are undiscovered sources at least as large as what we've found so far.

Sure, that seems likely...

And even with known reserves, we were good for 100+ years, so I consider the people arguing (in the past) for a plutonium economy to be gulty of special pleading. Anyway, apart from France, the idea is dead in the water. It costs a lot to extract, its natural radioactivity is much more intense than U235, making it harder to handle, and its aptitude as either the makings of a terrorist fission bomb, or at least the casing for a dirty conventional bomb, make it a high security risk. Put those factors together, and hard-nosed economists will give it the thumbs down...

[Schneibster]

One of the big problems with disposing of the radioactive waste if you don't reprocess is, you're putting U-238 in enormous quantities into the storage depot. If you seal it up so it won't get out for 10,000 years, how do you get it out in 100 years when you want it? Oops.

[Gawdzilla Sama]

One of the big problems with disposing of the radioactive waste if you don't reprocess is, you're putting U-238 in enormous quantities into the storage depot. If you seal it up so it won't get out for 10,000 years, how do you get it out in 100 years when you want it? Oops.

Tell a ten year old boy he's not allowed in that area?

[MiM]

One of the big problems with disposing of the radioactive waste if you don't reprocess is, you're putting U-238 in enormous quantities into the storage depot. If you seal it up so it won't get out for 10,000 years, how do you get it out in 100 years when you want it? Oops.

You dig. Much in the same way you dug the original tunnels for the disposal. At least this is part of the concept for final disposal in Finland, where the entrance tunnel is already at the level of about 450 m under ground, where the disposal areas are planned to be excavated. The plans are to start the disposal in 2020. On the other hand, these tunnels will be in use for about 100 years, so there is still plenty of time until those tunnels will be backfilled and sealed.

http://www.posiva.fi/en/final_disposal/retrievability/

[Cormac]

Even the spent fuel isn't the end of the problem. If you look up the UK Nuclear Decommissioning Autority website, you'll find their business plan for the next two years.

http://www.nda.gov.uk/

The projected public expenditure is approx £2 billion. The original total programme estimate was £55.8 billion. That cost increased to £72 billion, and then £73.6 billion over a 100 year period.

Given that more stations are being built and existing stations are being expanded, this cost will only increase.

Some interesting points:

1. They're not talking about spent fuel - they're talking about the buildings and power plant components. They're also tracking down "grain-of-sand" sized particles that escaped into the local environment, in their efforts to completely clean up the areas surrounding the power stations. (Although this last activity has recently been abandoned after over a decade of word and expense.

2. These are costs that are borne completely by the public purse, and they are not built into the economic life cycle of the power stations.

All this, and then we should consider that nuke-you-lar power stations are a big and easy target for anyone willing to kill on a grand scale.

[Svartalf]

Of course, it might be interesting to reuse already irradiated material from old stations into the building of new ones... might save on costs, and delay having to find a resting home for those tons of stuff for 30 or 50 years.

[Cormac]

Of course, it might be interesting to reuse already irradiated material from old stations into the building of new ones... might save on costs, and delay having to find a resting home for those tons of stuff for 30 or 50 years.

I should have clarified. That is 2 billion over the next 2 years.

The most expensive part is building bespoke robots to enter, deconstruct, handle, and package the "parts", because it would kill a human being to be in close proximity - or so the engineers building the robots said.

The robots will themselves become lethally radioactive. I'm not sure whether or not they'll have to build robots for the robots.

[Cormac]

Of course, it might be interesting to reuse already irradiated material from old stations into the building of new ones... might save on costs, and delay having to find a resting home for those tons of stuff for 30 or 50 years.

Oh, and I don't think it can be safely recycled. The robots will be cutting, chopping, and crushing bits and pieces as they deconstruct. So the parts won't be directly usable. Even if they were, surely reactor designs would be different.

[Svartalf]

Of course, I'm pretty sure that there's a whole lobby concerned that new power stations be built only from 'fresh' material, and with getting paid to dispose of the remains of old ones, so I'm pretty sure no serious study has been made as to the savings and feasibility that would go with recycling all that concrete and steel, not to mention the rarer materials.