Naked Science Forum
Non Life Sciences => Technology => Topic started by: Paul Anderson on 23/02/2009 22:30:01
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Paul Anderson asked the Naked Scientists:
HI Chris and team,
There is talk of expanding nuclear power in various countries. The pro-nuclear faction say they will be safer than older breeds of nuclear power station.
As far as I am concerned I would like to know how they are going to dispose of the nuclear waste. There are still dangers related to the re-processing of spent rods in nuclear power stations.
I am still opposed to the visits of nuclear powered vessels into NZ waters. Even on the high sea a US submarine came to the surface under a Japanese vessel and just recently were they British and French vessels which collided on the high seas?
Someone is going to jump down my throat now and say Oh but they were not nuclear vessels!, but if we as humans cannot prevent conventional vessels from colliding, how is it going to be any different with nuclear vessels? There is even more chance for collisions in harbours when everyone is in close proximity, plus the danger to the nearby citizens in the city attached to the port in the harbour.
Comments?
Regards
Paul
NZ
What do you think?
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I think you are right to be concerned. It is human error which should give us the greatest concern.
We have the technology, all we have to do now, is find out how to use it!
Nuclear power stations may well be safer, but nuclear waste will be a problem for a very long time. It's all very well for us now to say we can handle it, but are we not just storing up huge problems for those in the future to have to clear up?
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It's all very well for us now to say we can handle it, but are we not just storing up huge problems for those in the future to have to clear up?
Yes, I quite agree. This might just be the beginning to a better future: Gallium and uranium join forces (http://www.rsc.org/chemistryworld/News/2008/December/23120801.asp)
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No matter how much nuclear waste you produce and have to store somewhere, that downside is absolutely nothing when you compare it to the CO2 you would be releasing if you used a coal power plant instead. The CO2 output into the atmosphere is what will store up huge problems for the future, not a few neatly contained nuclear waste sites.
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I'm sure that I heard recently that one of those clever German scientists had managed to re-used nuclear waste multiple times to the point where there was very little left.
Edit: All right, Scottish, then.
"Scientists at the University of Edinburgh in Scotland have created a molecule called a macrocycle, which can eat the uranium ion uranyl from spent nuclear fuel rods. Why is this important?
Because uranium fuel rods in a nuclear reactor use only 5 percent of their energy, the need to find a way to reprocess this spent fuel into a re-usable form is very high ... and macrocycle may do just that. It weakens the uranyl's structure, meaning that the spent fuel rods could be broken down and the inert elements disposed while the reactive elements are used to create new fuel elements. (Information courtesy of the July 2008 issue of Popular Science.)"
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The Low Level Waste Repository near Drigg, Cumbria was an ordnance factory during the war and was then used for nuclear waste disposal/ stroage. In the late 90's there was a project to retreive plutonium contaminated material from old explosives magazines. Items were brought out, assayed and plutonium contmainated stuff taken back to sellafield to be cleaned up.
It intrigues me that despite knowing how potentially harmful and long lived material contaminated with radioactive elements can be that no one bothered to keep any decent records...
http://www.whitehaven-news.co.uk/former_workers_asked_to_tell_what_s_buried_at_drigg_nuclear_dump_1_513354?referrerPath=home/search_results_page_2_2837 (http://www.whitehaven-news.co.uk/former_workers_asked_to_tell_what_s_buried_at_drigg_nuclear_dump_1_513354?referrerPath=home/search_results_page_2_2837)
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Paul Anderson asked the Naked Scientists:
HI Chris and team,
There is talk of expanding nuclear power in various countries. The pro-nuclear faction say they will be safer than older breeds of nuclear power station.
As far as I am concerned I would like to know how they are going to dispose of the nuclear waste. There are still dangers related to the re-processing of spent rods in nuclear power stations.
I am still opposed to the visits of nuclear powered vessels into NZ waters. Even on the high sea a US submarine came to the surface under a Japanese vessel and just recently were they British and French vessels which collided on the high seas?
Someone is going to jump down my throat now and say Oh but they were not nuclear vessels!, but if we as humans cannot prevent conventional vessels from colliding, how is it going to be any different with nuclear vessels? There is even more chance for collisions in harbours when everyone is in close proximity, plus the danger to the nearby citizens in the city attached to the port in the harbour.
Comments?
Regards
Paul
NZ
What do you think?
The presupposes that a collision will allow for contamination. You have a reactor which is inside of its own containment pressure vessel, and fuel that is contained in its own material.
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No matter how much nuclear waste you produce and have to store somewhere, that downside is absolutely nothing when you compare it to the CO2 you would be releasing if you used a coal power plant instead. The CO2 output into the atmosphere is what will store up huge problems for the future, not a few neatly contained nuclear waste sites.
1) Coal power is not the only alternative to nuclear power. It is however probably one of the worst.
2) You should compare the release of CO2 (are non-toxic gas) to the RELEASE of nuclear waste (extremely toxic in even tiny amounts). The area of Chernobyl is off limits for humans for another 500 years right now.
If you want to be pessimistic/optimistic about technology it would be fair to do it for both sides of your argument.
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If you want to be pessimistic/optimistic about technology it would be fair to do it for both sides of your argument.
Very well, I will elaborate.
1) Coal power is not the only alternative to nuclear power. It is however probably one of the worst.
I know it's not the only alternative, but it's the most realistic.
2) You should compare the release of CO2 (are non-toxic gas) to the RELEASE of nuclear waste (extremely toxic in even tiny amounts). The area of Chernobyl is off limits for humans for another 500 years right now.
Chernobyl is the only nuclear accident that has ever caused loss of life or damage to the environment. And I think the damage done to the uneducated publics perception of nuclear power is just as tragic.
In modern nuclear powerplants (even the very few in the Soviet Union that are Generation-1 like Chernobyl was have been retrofitted with preventative improvements), a Chernobyl type incident cannot happen. Even if every worker at the plant simultaniously keels over from a heart attack, they are fundamentally designed so that the reaction cannot be sustained if anything goes wrong.
Even the accident at Chernobyl shouldn't have happened, it was a monumental example of human stupidity. Thankfully today, no matter how stupid a worker is, they cannot cause a repeat of Chernobyl.
This is what happened at Chernobyl: (As explained by Brain Dunning in his Skeptoid podcast - http://skeptoid.com/episodes/4092 )
Chernobyl was suffering from inadequate funding. Much basic maintenance had never been performed. It had only a skeleton crew, nearly all of whom were untrained workers from the local coal mine. The only manager with nuclear plant experience had been a worker installing small reactors on board Soviet submarines. Some genius decided to run a risky test of a type that no experienced nuclear engineer would ever gamble on. The test was to shut down the water pumps, which must run constantly in that type of reactor; and then find out whether the turbines, spinning on their momentum alone, had enough energy to restart and run the pumps during the forty-second delay before the backup diesel generators would kick in. The test was so risky that one faction within the plant deliberately disconnected some backup systems, trying to make the test too dangerous to attempt. The test was run anyway. It didn't work, the pumps couldn't keep up, the graphite core caught fire, the coal miners couldn't find any shovels so they didn't know what to do, and the reactor exploded. If you think I'm exaggerating this, there are extensive resources both online and in print, if you really want the hairy truth. In this short space I'm probably not even giving you ten percent of what a travesty this was — I'm tempted to call it a joke but it's so not funny. For example, they scheduled this right in the middle of a shift change, and the new workers coming in didn't even know what was going on.
Two people died that day, and some 30 to 60 people were dead within three months. Predictions of eventual cancer deaths caused by the radiation run from 1,000 to 4,000. And, of course, the damage to the local environment is extensive and difficult to estimate. The terror of a radiation cloud blowing across Europe was the second nail in the coffin of American nuclear power.
Not only was Chernobyl a monumental failure of the human element, the plant was a Generation I design, specifically an RBMK reactor, which is generally regarded as the least safe reactor type ever built. One design flaw is that the core used combustible graphite, and this distinction is the main reason that Chernobyl-type disasters are not possible in most reactors around the world. Only a very few Generation I designs are still in use, all in the former Soviet Union, and all have been retrofitted with improvements intended to prevent this type of accident. Other nations have long been lobbying for the closure of these reactors, and rightfully so.
Actually, I would argue that coal powerplants do much more damage to the environment. Here's a table showing emissions of several different energy resources:
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.uow.edu.au%2Feng%2Fphys%2Fnukeweb%2Fimages%2Freactors_05.jpg&hash=ace0cf73972104c03a717f953168c4a1)
Apart from the blindingly obvious difference in CO2 emissions, notice how much particulate matter is emitted by coal? A report in the Journal of the American Medical Association found that some 50,000-100,000 Americans die each year from lung cancer caused by particulate air pollution, the biggest cause of which is coal-burning power plants in the midwest and east. Even taking the maximum predicted death toll from Chernobyl, we would need a Chernobyl-sized accident every three weeks to make nuclear power as deadly as coal and oil already is.
Along with the oxides that are released when burning coal for use in power stations it is important to note that releases from coal combustion also contain naturally occurring radioactive materials, mainly uranium and thorium.
The Oak Ridge National Laboratory gives statistics on the levels of radioactive material given off by a coal fired plant. They estimate that to run your average 1000 megawatt coal-fired power plant, you need to burn about 4 million tonnes of coal. That 4 million tonnes of coal contains 5.2 tonnes of uranium, 12.8 tonnes of radioactive thorium, as well as 0.22 tonnes of radioactive potassium-40.
In Australia radiation safety standards are set by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) which are in line with international practice. The annual dose for members of the public (excluding background radiation and medical uses such as X-Rays) is set at 1 millisievert.
When taking into account the populations surrounding power plants the actual dose received by an individual living near a properly operated plant is generally below these levels. Still coal fired power stations end up giving a higher dose to the population than nuclear power plants.
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1) Coal power is not the only alternative to nuclear power. It is however probably one of the worst.
I know it's not the only alternative, but it's the most realistic.
I agree with you that coal power is not a good alternative at all. I heard a long time ago that by burning coal more radioactive material is distributed in our environment than by nuclear power plants (assuming all goes well). You don't have to convince me of the negative effects of burning coal. I support you point of view there 100%.
But what do you mean by "realistic"?
And, radioactive waste does not only appear accidentally. It is a result of nuclear power generation and something has to be done with it. Is your image of a "few neatly contained nuclear waste sites" not a bit too pretty?
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By realistic I mean it's more economically viable to just burn coal for power than to build solar plants or wind turbines, and it's more dependable. You know you how much energy you can get, you can get a buttload of it, and the weather doesn't matter. So despite its environmental harm it remains an attractive option.
In my wording "few neatly contained nuclear waste sites" i'm trying to counteract the stigma associated with the thought of nuclear waste, some people seem to think its just dumped in the river and the entire area is soon populated with 3-eyed fish and squirrels that can shoot laser beams from their eyes. But I don't think it's too pretty, especially in comparison to the waste from coal fired powerstations. At least you can control nuclear waste and make sure it's stored safely, it's not just vented into the atmosphere.
And as dentstudent mentions, there are new technologies in the works that brings the amount of nuclear waste produced to near-zero.
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By realistic I mean it's more economically viable to just burn coal for power than to build solar plants or wind turbines, and it's more dependable. You know you how much energy you can get, you can get a buttload of it, and the weather doesn't matter. So despite its environmental harm it remains an attractive option.
Agreed. I am afraid in the long run every shred of fossil fuels will be used. Let us hope we use it to develop technology that allows us to become independent of those fuels. In a way, fossil fuels could be seen as a nice little "present" from the past we could use to build a world that functions well and at a high level without them. Can't wait to see this happen more.
In my wording "few neatly contained nuclear waste sites" i'm trying to counteract the stigma associated with the thought of nuclear waste, some people seem to think its just dumped in the river and the entire area is soon populated with 3-eyed fish and squirrels that can shoot laser beams from their eyes. But I don't think it's too pretty, especially in comparison to the waste from coal fired powerstations. At least you can control nuclear waste and make sure it's stored safely, it's not just vented into the atmosphere.
And as dentstudent mentions, there are new technologies in the works that brings the amount of nuclear waste produced to near-zero.
Yes, some people have strange perceptions about the effects of radioactivity. So, where do we store this waste? How will people store it if their economies collapse and they need to find "cheap" methods to store the stuff? Is a nuclear power plant (or waste treatment facility) only safe as long as its location is in a wealthy area? This is serious high-tech and I believe therefor expensive.