Chernobyl Legacy

Discussion in 'Earth Science' started by lightgigantic, Oct 20, 2007.


How much are you in favour of Nuclear Power

  1. All for it - no problems with buying real estate next door

  2. Not ideal, but better with it than without it

  3. undecided

  4. uneasy about it - concerned about long term impact

  5. Its a human disaster just waiting to happen

  1. iceaura Valued Senior Member

    So any future disasters will have to be from some other, unexpected or inadequately recognised, mechanism (such as the main reactor control box falling off its mounting). So?
    None of what follows that statement contradicts anything in my post. How is what I posted about the mentality involved in this boondoggle "incorrect" ? This, for example, further illustrates the mentality I complain of:
    I don't favor leaving it stashed all over. I illustrate the shortsightedness of the people pushing nuclear power, who have painted us into this ridiculous and expensive and dangerous corner, and now propose to expand their operations. These people cannot be trusted in their reassurances or their descriptions of safety, cost, or efficacy. Yucca Mt, for example, is not a very good storage option for several reasons - but it's the best they could find, so they call it "ideal".
    { a calculation here has been removed for checking. It was from memory, and I can't remember whether it required maximum possible efficiency improvements. If you miss it, I'll put it back when it's been checked}

    There is far more efficiently usable real estate for heat engine solar than there is for geothermal, hydro, or wind.

    There is no safe and efficiently usable real estate for siting a nuclear power plant.
    Those bureaucratic and political factors are what enforced what minimal and untrustworthy safety standards we have. They are not optional, and they are not going to go away if nuclear power is to be installed with even the minimum standards that saved our asses at Three Mile Island, or more recently at Monticello and that Japanese reactor - by sheer luck.
    Put those hundreds of billions in government subsidy and tax breaks and so forth into heat engine solar, including the waste disposal and any kind of even minimal risk assessment, and then do the math on the remaining costs. It's probably cheaper right now, despite the fifty year head start of nuclear engineering, with possible improvements in the economies of scale (currently uninvestigated) not even factored in.

    Or, if you want immediate payoff, put those governmental billions into higher efficiency use of current production. The gain there has no uncertainty or downside at all.
    Last edited: Oct 23, 2007
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  3. Echo3Romeo One man wolfpack Registered Senior Member

    ...the conditions that led to the Chernobyl explosion will never be repeated again because it is physically impossible to get that kind of power spike in western reactor designs.

    Your facts about Yucca Mountain were all wrong.

    Everything I know about nuclear engineering I learned from Greenpeace pamphlets!

    I'm not sure which specific event you're referring to with "that Japanese reactor" but the casualties at TMI-2 and Monticello are pretty much textbook examples of how fault tolerant the technology is.

    I'm all for increasing distribution and consumption efficiency, but you will never account for projected demand by that measure alone.
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  5. Challenger78 Valued Senior Member

    For me Its a step australia has plenty of desert to bury the waste under/ but will it truly lead to better forms of power like fission ? (not an expert..but thats better right?)
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  7. iceaura Valued Senior Member

    And the response to that is already given: So?

    There are a thousand possible disasters. There are disasters you haven't even thought of, let alone securely prevented. You've got a large nuclear reactor operating at the head of the Mississippi River. That's a mistake.
    So why didn't you contradict one of them ? Yucca has several serious defects, as a solution to the waste storage problem. And in the jam we're in, it's the best we can do. That's not a good situation.

    Let's not get painted into any more such corners, eh?
    They were textbook examples of how easily experts can be fooled into thinking they've prepared for all major contingencies in a complex system.

    We were lucky. Period. The safety features and the technological backup were not "tolerant" - they were breached in an unpredicted manner, and major disaster avoided by unplanned and undesigned circumstance.

    I haven't read any, but I'd bet that Greenpeace pamphlets could teach you a lot about solar power. Where did that shortage of prime real estate nonsense come from? Arizona and Nevada are pretty big places. Mexico is even bigger.

    At current demonstrated levels of harvesting efficiency, how much high desert area would it take to meet the total energy needs with of the US with solar harvest alone, say ?

    Nuclear engineering has little to do with this, except that I've noticed that expertise in it tends to blind people to obvious problems. It takes a nuclear engineer to dismiss something like the threat from nuclear proliferation or disgruntled employees or waste transport carelessness as somehow unimportant.

    It was a bunch of nuclear engineers who built all these plants we don't know what to do with, and need to monitor constantly and handle continual emergencies in just to keep from wrecking our major river systems. It was a bunch of nuclear engineers who sold this technology to everyone from the Shah of Iran to the local zoning commission of some county in Washington state. It was nuclear engineers who led off by talking about power so cheap it wouldn't pay to meter it. It was nuclear engineers who decided to handle megaton quantities of plutonium contaminated waste by dumping it in the ocean. They were and are fools in this matter, on average and in general.

    If you gain more, dollar for dollar, by paying for efficiency improvements rather than expansion of production, than paying for production expansion is a net loss.
  8. Avatar smoking revolver Valued Senior Member

    Fission or fusion?
  9. orcot Valued Senior Member

    I'm all for if you can activly ban all noobs and sicko's. So no selling plutonium to angry incompetents or a noble price wannabe who's yust dying to see what happens if you touch those couple of buttons.
  10. Nasor Valued Senior Member

    If you think that current nuclear power designs aren’t safe, it simply means you need to keep working on designing safer plants. If you think nuclear waste is a problem, you need to works on better fuel reprocessing techniques. It’s stupid to say “Since there have been problems before, lets scrap the technology.” There’s nothing fundamentally unsafe about nuclear power; its simply a matter of deciding how much risk you are willing to tolerate and designing your reactor accordingly.
  11. Nasor Valued Senior Member

    Nuclear waste can be greatly reduced, both in terms or quantity and hazardousness. Better fuel reprocessing, different reactor fuels, and different reactor designs can all help tremendously. Again, if you think that the current amount of nuclear waste being produced is unacceptable, that just means that you need to work on producing less waste.
  12. Read-Only Valued Senior Member

    Exactly. And one the the main things that the fear-mongers - like IceA - keep overlooking is that MAJOR strides have been made since the accident at Three Mile Island. For example, there are at least two different designs that have been approved for use that use PASSIVE emergency cooling - no pumps (involved which was the cause of failure at TMI).

    We've also become MUCH smarter about disposing of the waste - no more idiotic just dumping in the oceans or anywhere else. In fact, practically everything the naysayers are complaining about or are afraid of are from decades ago! They haven't bothered to keep up with the developments all during that time.

    The two biggest problems left to overcome are security and safe disposal of material that cannot be reprocessed. And besides that, reprocessing technology has also made tremendous progress - the actual amount that has to be disposed of today is only a small fraction of what it was decades ago.

    In short, these cry-babies are fearful of ghosts and goblins that don't exist anymore. They are WAY behind the in the current technology and designs.
  13. iceaura Valued Senior Member

    So the English aren't piping it out to sea any more. When did they stop, and why? Do you suppose it had something to do with fearmongers and ignorant crybabies making a fuss ?

    For an idea of the nature of the problem, especially newly begun research into some corrosion problems jsut discovered in the past couple of years:

    We've become so smart about disposing of waste (don't forget the plants themselves,when they're decommissioned. We might want to figure that one out before we build a few hundred more) that we have finally realized we don't have any good way of doing it. Some of us, anyway.
    And they are therefore foolproof, and nothing bad will happen. We know this because this time we've thought of everything. Except control boxes falling off the wall, and unprecedented earthquakes - but no doubt still further improvements will patch those holes, and they are the very last holes. We're sure. You can bet the Mississippi River and the Iowa mollosoil on it.

    Still missing is the cost comparison with alternatives. This nuke stuff not be cheap.
    Last edited: Oct 24, 2007
  14. Read-Only Valued Senior Member

    I know you don't realize it but you sound just like many people long ago that complained about those "new-fangled" trains. They were going to scare livestock to death and upset the internal organs of people who rode on them. One reporter wrote a sensational news item about taking a fearful ride on one as his assignment - and traveled at the "breakneck speed" of 28 miles per hour!
  15. Echo3Romeo One man wolfpack Registered Senior Member

    So read the goddamned thread and what I was responding to before you go beating up a strawman that I think nuclear fission is an ideal endgame solution and there will never be any accidents related to it ever again.

    Already answered, read thread.

    Well, no, not really. TMI-2 experienced a cascade failure of several critical control and safety systems, each of which either compounded on, or directly caused, one another. These events happened in a series of stages, in chronological order:
    1. A pump in the secondary coolant loop tripped offline. When this happened, the reactor and turbines both immediately shut down. The core, still hot from operation and still generating heat from decaying fission products, heated the water in the primary loop enough that the relief valve on top of the pressurizer opened. This was done at 2300psi to lower the pressure in the primary loop, and the excess coolant was dumped into an overflow tank.
    2. Once the pressure in the primary loop was below the relief valve's actuation point (about 6%), there was another failure: the valve failed to re-seat itself, continuing to vent cooland into the relief tank.
    3. A third failure occurred when the relief valve indicator in the control room indicated that the valve had closed properly.
    4. When the reactor scrams and turbines halt, the emergency core cooling system is supposed to activate. The ECCS at TMI-2, however, did not. A valve was misaligned in a test two days previously. That problem was noticed within a few minutes and the ECCS began to operate normally.
    5. The primary coolant loop was flushed with fresh coolant and the core temperature began to fall. The relief valve on the pressurizer, still partially unseated, allowed coolant from the ECCS to continue to fill the overflow quench tank. As the ECCS pumps continued to attempt to fill the primary loop, the reserve coolant continued to fill the quench tank. Ultimately the quench tank overflowed primary coolant, which had been exposed to the core, into a relief tank outside of the primary containment building.
    6. Eventually that external relief tank also overflowed, this time into the sump of the auxiliary building. Some of the vapors from the primary coolant escaped this building by way of some very impressive filters designed to trap exactly these sorts of contaminants. The vapor that made it out had been exposed to overflow water, which had been inside the pressurizer, which had been exposed to primary coolant, which at one point had been exposed to the radioactive core. It is this leak that had everyone wringing their hands over. All told, it was about 95 curies of non-condenseable gases present in any operational reactor core: primarily Krypton 85 and Xenon 136, with a very small amount of dissolved Iodine-131.
    7. After all this venting had occurred, the pressure back at the core had dropped to levels close to atmospheric and as a result the remaining coolant flashed into steam. Normally, this would have been easily correctable by the operator adding more coolant. However, due to the faulty instrumentation atop the pressurizer, the indicators told the operators that the primary coolant loop was still at full capacity. The water continued to drop, and eventually a steam bubble formed at the top of the reactor vessel in the void. This steam delaminated some of the zirconium cladding from the fuel elements, which oxidized under the steam, leaving a large hydrogen bubble at the top of the core. Over the next seven hours the hydrogen bubble was exposed to the top of the core, but it was eliminated thereafter when coolant pressure was restored, thus compressing the bubble back into the fluid. The remnants of the gas were removed over the next few days by some rather crafty use of air injectors elsewhere in the coolant circuit.
    8. While the fuel rods were exposed to the bubble, they were not immersed in coolant. Some of them got soft and plastic-like. The core damage was extensive.
    And the consequences?

    So, here we have a cascading failure of several critical subsystems to the reactor and not much happened. TMI-2 stopped running, heated up for a little bit, and then just kind of sat there. The total radiation exposure was about 1% above background for 30 minutes within a few hundred feet of the vent. In every sense of the phrase, nothing happened. We're talking about enough radiation to X-ray a pidgeon, or take a few dental X-rays of a single person. Aside from propaganda-induced stress (which, evidently, still lingers today) there were ZERO medical effects as a result of the reactor casualty. And despite what crappy Jane Fonda movies suggest, it did not "melt down". The containment vessel held together in the heat because it was designed to tolerate exactly such a fault. That is the textbook definition of fault tolerance. To seriously contend that luck had anything to do with the outcome betrays an abysmal ignorance of the relevant science.

    For a nuclear reactor to generate power, you need a) fuel, and b) a moderator. Without fuel, nothing happens of course. Without a moderator, nothing happens, either. If the moderator goes a way, it is physically impossible for the nuclear reactions to continue because neutrons won't be thermalized (slowed down) so they can be captured by the fuel, and the reactor shuts itself down. No human intervention is needed, and indeed if the moderator went away, nothing anybody could do could make the reactor do anything but sit there.

    In a US power plant, water is both the moderator and coolant. So let us imagine that we removed all the control rods, shut off all the safety features, and drained the coolant. What would happen? Nothing. With no moderator, it is physically impossible for the reactor to continue generating power, and it shuts itself down. The core would just sit there and be hot.

    This is, in fact, what happened at Three Mile Island. Bad training and extreme stupidity produced an accident with exactly zero external impact. Horrors!

    Since I have nothing better to do tonight, I'll run some numbers for you:
    • Average Solar Flux for North America: 150W/m^2 -This is a seasonal average, and takes day/night into account, but not weather. In reality it would be less, but I'll use it as a working assumption.
    • US Annual Energy Consumption: 97 Quadrillion BTUs (102 Quntillion Joules, 243 Billion tons of TNT)
    • Solar Panel Efficiency: 6% (amorphous silicon, the only feasible material at the scale we're talking)
    • Energy required to manufacture a-Si panels:120kWh/m^2 (432MJ/m^2) as a generously conservative estimate. I don't know if this counts mining, refining, transportation, installation, cabling, power conversion, substations, transmission, etc. I'm pretty sure it doesn't. If we want to include the energy required to properly dispose of the panels as HAZMAT, this number goes up even further, but I'll leave that out for now.
    • Energy required to mount an a-Si panel: appx 120kWh/m^2 (432MJ/m^2)
    • Area of Land in United States: 9.16 million square kilometers
    • 1 Joule = .000948 BTU

    • Land Area of Florida: 137,000 km^2
    • Land Area of Georgia: 154,000 km^2
    • Land Area of Louisiana: 134,382 km^2
    • Land Area of Texas: 686,241 km^2
    • Land Area of California: 404,298 km^2

    Solar energy absorbed annually per m^2:
    365 days * 24 hours * 60 minutes * 60 seconds * 150W/m^2 = 4.7 Billion Joules

    Solar energy absorbed annually per km^2, without taking weather into account:
    4.7GJ * 1000 * 1000 = 4.7PJ

    Assuming 50% reduction due to clouds and other inclement weather:
    4.7PJ * 0.5 = 2.35PJ

    Break-even point for energy for a-Si Solar Panels:
    864MJ/m^2 / (150W/m^2 * 6% * 50% * 60 * 60 * 24 * 365) = 6 years
    For this that missed the significance of this, it means spending 6x our entire annual energy consumption on solar panel production alone

    Electrical energy generated annually per km^2 of a-Si solar panels:
    2.35PJ * 0.06 = 141 Quadrillion Joules

    Square kilometers of solar panels required to meet US energy requirements:
    102EJ/141PJ = 723,000 Square Kilometers. That is larger than the sum total combined land area if you covered every square inch of of California, Florida and Georgia. Not even the vast wastelands of Texas have enough room.

    And that is not even counting the massive batteries you'd have to use to store energy produced during the day and consume it at night, the entropic inefficiencies inherent in that process, the inefficiencies of running the grid through inverters, the increased transmission losses when Seattle draws its power from a field in Texas versus a nearby plant, etc, etc. We would probably end up with MASSIVE hydroelectric projects where we pump water uphill all day, and power generators all night, wash-rinse-repeat. And with all the inefficiencies, would probably triple the amount of power (and solar cell-covered states) required. The utter impracticality of it notwithstanding, I can't see how widespread destruction of the ecosystem on such an unprecedented scale would be preferable from an environmental standpoint.


    Your personal bias aside, this has jack and shit to do with the technology.

    Read the link I posted. Focus on the parts about projected demand. Unless your mysterious efficiency improvements include the construction of a magical jelly bean field that powers the country with rainbows and kittens, the second law of thermodynamics says we need a lot more generating power within the next 20 years or the grid will go dark.
  16. iceaura Valued Senior Member

    You're the one who posted about the impossibility of another Chernobyl, in response to my post about the unreliability of general assurances from experts in this field. Irrelevant to my post. Why?
    Thread read, no answer found. Yucca Mt is geologically suspect (massive water intrusions since the glaciation, fissures to the water table, etc), the available volume is what it is (you dismiss the restrictions as senseless, but they have their reasons), the 10,000 year criterion is reasonable for an important fraction of the waste, the transport problem is serious, and so forth.
    Lucky us. Bet the farm - or the Ohio River - on the next one?

    Your numbers are both outdated, for solar panels (6%?) and irrelevant for solar heat engines located in ideal areas - of which the US has vast quantities, and Mexico more.

    I did mention solar heat engines specifically, located in the Arizona desert and similarly. So this for example (along with practically every other number you posted) is beside the point:
    an irrelevant number for responding to my posts. Actually, it is an irrelevant number anyway - are we distributing our solar panels at random across the continent, then? Greenpeace pamphlets probably do better, there - check 'em out.
    So? The technology is fine, when it works and nothing goes wrong, as far as it goes. It's extremely expensive, and radically unsafe, and creates a zillion external costs and problems, though. And nuclear proponents have a long track record of flagrant - even comical - failure to take those into account.

    And that's giving them the benefit of the doubt. Deliberate deception and concealment has been a reasonable possibility, something we have to consider. There are billions of dollars of taxpayer and ratepayer moolah riding on this issue.

    We can't make this decision based on the reassurances of nuclear engineers and similar technical experts. They are among the least reliable sources of information on critically relevant topics of concern here.
  17. Read-Only Valued Senior Member

    This as much as anything exhibits the absurdity of your viewpoint. If we (you) can't trust the "nuclear engineers and similar technical experts", who DO you trust - amateurs, palm readers and astrologers?!?!?!
  18. pjdude1219 screw watergate i want to know about zaragate Valued Senior Member

    not well thought out now there is an understatement they turned off most of the safety things
  19. iceaura Valued Senior Member

    I said we can't trust the assurances of the tech experts - obviously we trust them for tech expertise.

    As far as risk, cost, and externalities, palm readers might be better, yes - if they had reasonable intelligence, some experience in life, and enough science education to get the general idea.
  20. Read-Only Valued Senior Member

    Precisely my point - and why I put the word "NOT" in capital letters. You might not be aware of the details of the test but it had already been run before at Chernobyl and other nuclear power plants in Russia.

    Basically, it was a test of a "flywheel restart" and required some of the safety features be disabled. But when the reactor became unstable (which that design was prone to do) the operators made a serious mistake by issuing a shutdown command which resulted in a HUGE power surge. The rest is history - but you appear to not have knows the basics of the test OR the test conditions.
  21. Read-Only Valued Senior Member

    Baloney!!:bugeye: So much for you having a scientific mind.:bugeye:
  22. pjdude1219 screw watergate i want to know about zaragate Valued Senior Member

    yeah i get that but you would think once things started to go wrong they would have turned some of them back on
  23. Read-Only Valued Senior Member

    No, you haven't gotten it quite yet. They were following the test procedures and the unstability was expected - it had been noted before. The problem was that the operators were poorly trained and broke protocol (the proper procedures) when they decided to shut it down. If they had continued according to the plan, the accident probably would NOT have happened.

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