Fukushima radiation fallout vs Chernobyl visualized

[hobbsyoyo]

Even if the technology is overly dependent on political issues whether it is probably used or not, it perhaps best not to use. One problem is also of scale: Decommissioning can take years and the meantime require not resources to operate. If the power generated by nuclear plants suddenly isn't in demand any longer, you can't get rid of it very soon.

Right, but that's a political issue as by and large government should be responsible for ensuring shut downs and waste disposal are handled efficiently but leave it to the markets to take care of and/or let the NIMBY principle override common sense. In the US, we could and should dispose of nuclear waste responsibly, but we don't because NIMBY has driven political consensus to kick the can down the road so to speak.

Also, coal and gas plants - for all their faults - cannot go Fukushima. Nuclear fission is cleaner than coal if you discount the risk, though you cannot possibly predict the risk of meltdown and then what will happen next. Nuclear fusion doesn't have those kind of faults since the waste is negligible (you can leave the radioactive waste inside the reactor as fusile waste has a half life of 50 years compared to the centuries fissile waste).

They cannot got Fukushima, for sure, but the impact of an occasional Fukushima compared to the everyday impact of coal/gas plants is negligible. I don't mean to trivialize how serious nuclear meltdowns are, but they are by far the exception to the rule while coal and gas are destroying the environment (and outputting lots of radiation) 24/7. You're right, you cannot predict meltdowns, but you can prepare for them and try and engineer better systems to handle serious faults. It is terrible that it took Fukushima to point out flaws in reactor design wrt to mega-tsunamis but the lessons were (hopefully) learnt and fixes being applied.

Chernobyl of course is another story as that plant shouldn't have been open to begin with - as I said before it was just a terribly designed plant that no one but the Russians would have operated in the 80's, much less today.

Fusion isn't a thing as yet but I'm all for pouring more money into researching it. Do note however, that most types of fusion reactors will produce radiation. This radiation is much less than what's produced in a fission reactor, but eventually it will irradiate components of a fusion reactor that will then have to be disposed of.

Also, please do not say 'it is Japan's or the USSR's fault, it won't fail near us!', because a failure elsewhere may already be bad enough for you, even if your country manages nuclear energy foolproof and flawlessly.

Oh dear, have I come off as that naïve?

 

[red_elk]

Chernobyl of course is another story as that plant shouldn't have been open to begin with - as I said before it was just a terribly designed plant that no one but the Russians would have operated in the 80's, much less today.

Except some design flaws of this reactor type, what were the problems with the plant? Modified version of RBMK reactors is still used in Russia in many places.

 

[hobbsyoyo]

http://en.wikipedia.org/wiki/RBMK

Certain aspects of the RBMK reactor design – namely the graphite-tipped control rods, the positive void coefficient characteristic and instability at low power levels – contributed to the 1986 Chernobyl disaster

I am not certain that only the Chernobyl type reactors (RBMK's) have these problems, but I according to the article only the Soviets used this type of reactor.

*positive void coefficient means that the reactor has a tendency to generate a sudden and uncontrollable burst of power if large steam bubbles, or "voids," are allowed to form in the reactor core, as they did before the accident.

** and why that is bad:
As reactor operators prepared to carry out a planned safety test involving one of the plant's eight turbine-generators, they inadvertently let steam voids form in the reactor's cooling water as it passed through the core, according to the Soviet report. The effect was akin to pressing a car's gas pedal to the floor.

As the fission accelerated, the reactor's heat output rose 330 million watts within three seconds. This triggered explosions of steam and hydrogen gas in the core that destroyed the reactor, blew the roof off the building and started a graphite fire in the core that spewed radioactive wastes into the atmosphere for the next 11 days.
http://articles.latimes.com/1986-08-23/news/mn-15781_1_design-flaws

 

[red_elk]

I thought you were talking about some other design flaws unrelated to the reactor type.
I'm quite familiar with the flaws of RBMK reactor and what events lead to catastrophe - IMO this was rather terribly planned and executed actions, rather than terrible design of plant itself.
Because this design is still used in modern plants, with additional safety measures (which could prevent Chernobyl-like catastrophe, but main reason of it was human factor, rather than bad design)

 

[peter grimes]

If I recall correctly the Chernobyl reactor was designed to make extracting the fuel rods for Plutonium processing efficient, since that was one of the purposes of the plant to begin with. The precludes certain safety measures (something about a welded steel reactor cask instead of a concrete lid??)

 

[Tahuti]

Right, but that's a political issue as by and large government should be responsible for ensuring shut downs and waste disposal are handled efficiently but leave it to the markets to take care of and/or let the NIMBY principle override common sense. In the US, we could and should dispose of nuclear waste responsibly, but we don't because NIMBY has driven political consensus to kick the can down the road so to speak.

Well, if you cannot be certain to dispose of nuclear waste, it is still a problematic aspect of nuclear energy, even if NIMBYism to nuclear waste is informed by ignorance - which NIMBYism at large often is. Fissile nuclear power requires an organisational scale that perhaps can not be taken for granted at all times in order to be operated safely and that in itself may already be an insurmountable pitfall.

Fusion isn't a thing as yet but I'm all for pouring more money into researching it. Do note however, that most types of fusion reactors will produce radiation. This radiation is much less than what's produced in a fission reactor, but eventually it will irradiate components of a fusion reactor that will then have to be disposed of.

I am pretty convinced that fusile material would need not to be disposed of because of its negligible size and extremely low half life time of 50 years.

 

[ObadiahtheSlim]

The biggest fault in Chernobyl was that inserting the rods to SCRAM (shut down) caused a sudden spike in power. This was a design fault and was part of the reason the West never implemented that design. The sudden spike caused a massive steam explosion. However that never would have happened if they hadn't have disabled other safety features and hadn't run in in such a dangerous way with a rookie crew.

Also one thing to keep in mind, nuclear is still the safest per kilowatt hour.
Energy Source Mortality Rate (deaths/trillionkWhr)
Coal – global average 170,000 (50% global electricity)
Coal – China 280,000 (75% China’s electricity)
Coal – U.S. 15,000 (44% U.S. electricity)
Oil 36,000 (36% of energy, 8% of electricity)
Natural Gas 4,000 (20% global electricity)
Biofuel/Biomass 24,000 (21% global energy)
Solar (rooftop) 440 (< 1% global electricity)
Wind 150 (~ 1% global electricity)
Hydro – global average 1,400 (15% global electricity)
Nuclear – global average 90 (17% global electricity w/Chern&Fukush)

Source: http://www.forbes.com/sites/jamesconca/2012/06/10/energys-deathprint-a-price-always-paid/

 

[Leonel]

So the west coast is going to become a radioactive wasteland that makes the Fallout games look like a walk in the park AAAAAAAAH!!!

 

[red_elk]

The biggest fault in Chernobyl was that inserting the rods to SCRAM (shut down) caused a sudden spike in power. This was a design fault and was part of the reason the West never implemented that design.

Yes, it was a design fault with control rods, which was later fixed. But as far as I know, whether an emergency shutdown procedure caused an explosion is not known with confidence. According to another version, at the moment when SCRAM was initiated, the reactor was already destroyed and "end-effect" (not sure how it's translated to English) of control rods was already irrelevant.

 

[gay_Aleks]

So the west coast is going to become a radioactive wasteland that makes the Fallout games look like a walk in the park AAAAAAAAH!!!

fun fact: almost all of the Fallout games happened on the East Coast (aside from one obvious one).

 

[peter grimes]

Fissile nuclear power requires an organisational scale that perhaps can not be taken for granted at all times in order to be operated safely and that in itself may already be an insurmountable pitfall.

Doesn't seem to be insurmountable for the US Navy. I wonder what their safety record is

 

[classical_hero]

The OP doesn't know what he is on about. But what we should be doing is figuring out how to make thorium reactors since the element is abundant and there is zero change of it being turned into a weapon(which is why they stopped working with it, since they wanted a weapon, not power at first) and the waste is not a radioactive like Uranium.

 

[hobbsyoyo]

The OP doesn't know what he is on about. But what we should be doing is figuring out how to make thorium reactors since the element is abundant and there is zero change of it being turned into a weapon(which is why they stopped working with it, since they wanted a weapon, not power at first)

Very much debatable.

and the waste is not a radioactive like Uranium.

I'm pretty sure this is blatantly false

 

[Cheezy the Wiz]

From the wikipedia article on Thorium-based nuclear power, which is actually a pretty interesting article:

Thorium, when being irradiated for use in reactors, will make uranium-232, which is very dangerous due to the gamma rays it emits. Though the irradiation process may be able to be altered slightly by removing protactinium-233. The irradiation would then make uranium-233 in lieu of uranium-232, which can be used in nuclear weapons to make thorium into a dual purpose fuel.

 

[gay_Aleks]

So, with India being most advanced in their Thorium-based nuclear power, they're actually braving for an eventual nuclear war?

 

[Leoreth]

The OP doesn't know what he is on about. But what we should be doing is figuring out how to make thorium reactors since the element is abundant and there is zero change of it being turned into a weapon(which is why they stopped working with it, since they wanted a weapon, not power at first) and the waste is not a radioactive like Uranium.

Who is "they"?

 

[Leonel]

fun fact: almost all of the Fallout games happened on the East Coast (aside from one obvious one).

Are you sure?

 

[Manfred Belheim]

Too bad I mentioned "economic damage", eh?
But even if I mentioned ecological damage: You don't think that evacuating hundreds of thousands of people and losing a significant part of your country doesn't cause economic damage as well, do you?

Oh yeah, I should learn to read. But anyway, it's minor compared to the damage done by burning fossil fuels.

 

[Flying Pig]

Doesn't seem to be insurmountable for the US Navy. I wonder what their safety record is

Their greatest safety provider is scale, by and large. The actual amount of power generation under the USN's steam is tiny compared with something like France or the USSR. Nuclear accidents happen extremely rarely; I can name something like five major ones in total. If you're operating enough plants, odds are that you're going to be the one who ends up with it.

 

[Aroddo]

The Thorium car:

Link to video.

Had to immediately think of fallout games again.

Kidding aside, Thorium, which is as abundant as lead, has several advantages:

Thorium is four times as abundant as uranium and as common as lead. The Thorium Energy Alliance (TEA) estimates "there is enough thorium in the United States alone to power the country at its current energy level for over 1,000 years."[17][18][unreliable source] "America has buried tons as a by-product of rare earth metals mining," notes Evans-Pritchard. "Norway has so much that Oslo is planning a post-oil era where thorium might drive the country’s next great phase of wealth. Even Britain has seams in Wales and in the granite cliffs of Cornwall. Almost all thorium is fertile Th-232, compared to uranium that is composed of 99.3% fertile U-238 and 0.7% more valuable fissile U-235. There is enough to power civilization for thousands of years."[19]

It is difficult to make a practical nuclear bomb from a thorium reactor's byproducts. According to Alvin Radkowsky, designer of the world’s first full-scale atomic electric power plant, "a thorium reactor's plutonium production rate would be less than 2 percent of that of a standard reactor, and the plutonium's isotopic content would make it unsuitable for a nuclear detonation."[15]:11[20] Several uranium-233 bombs have been tested, but the presence of uranium-232 tended to "poison" the uranium-233 in two ways: intense radiation from the uranium-232 made the material difficult to handle, and the uranium-233 led to possible pre-detonation. Separating the uranium-232 from the uranium-233 proved very difficult, although newer laser techniques could facilitate that process.[21][22]

There is much less nuclear waste—up to two orders of magnitude less, states Moir and Teller,[4] eliminating the need for large-scale or long-term storage;[15]:13 "Chinese scientists claim that hazardous waste will be a thousand times less than with uranium."[19] The radioactivity of the resulting waste also drops down to safe levels after just a few hundred years, compared to tens of thousands of years needed for current nuclear waste to cool off.[23]

According to Moir and Teller, "once started up [it] needs no other fuel except thorium because it makes most or all of its own fuel."[4] Because it is non-fissile, it can also be used with fissile material, such as uranium and plutonium, as a nuclear fuel.[17]

Since all natural thorium can be used as fuel no expensive fuel enrichment is needed.[23] However the same is true for U-238 as fertile fuel in the uranium-plutonium cycle.

Comparing the amount of thorium needed with coal, Nobel laureate Carlo Rubbia of CERN, (European Organization for Nuclear Research), estimates that one ton of thorium can produce as much energy as 200 tons of uranium, or 3,500,000 tons of coal.[24] Coal, as the world's largest source of carbon dioxide emissions, makes up 42% of U.S. electrical power generation and 65% in China.[25]

Some experts note possible specific disadvantages of thorium nuclear power:[26]

Breeding in a thermal neutron spectrum is slow and requires extensive reprocessing. The feasibility of reprocessing is still open.[27]
Significant and expensive testing, analysis and licensing work is first required, requiring business and government support.[17] According to a 2012 report by the Bulletin of the Atomic Scientists, about using thorium fuel with existing water-cooled reactors, it would "require too great an investment and provide no clear payoff," noting that "from the utilities’ point of view, the only legitimate driver capable of motivating pursuit of thorium is economics."[28]

There is a higher cost of fuel fabrication and reprocessing in designs that use traditional solid fuel rods.[17]

Thorium, when being irradiated for use in reactors, will make uranium-232, which is very dangerous due to the gamma rays it emits. Though the irradiation process may be able to be altered slightly by removing protactinium-233. The irradiation would then make uranium-233 in lieu of uranium-232, which can be used in nuclear weapons to make thorium into a dual purpose fuel.[29]