How has your opinion on the safety of nuclear power changed after the events in Japan?
Displaying poll results.55562 total votes.
Most Votes
- Will the United States government establish a Strategic Bitcoin Reserve before 2026? Posted on November 16th, 2024 | 12471 votes
- Windows on ARM is poised to take off. Who is going to be the ARM CPU supplier of choice for Windows? Posted on October 23rd, 2024 | 7559 votes
- How many devices are connected to your home WiFi network? Posted on December 12th, 2024 | 5390 votes
Most Comments
- Do stories about Bitcoin cause you to feel anger? Posted on December 12th, 2024 | 80 comments
- Windows on ARM is poised to take off. Who is going to be the ARM CPU supplier of choice for Windows? Posted on December 12th, 2024 | 67 comments
- Will the United States government establish a Strategic Bitcoin Reserve before 2026? Posted on December 12th, 2024 | 65 comments
Seems just as safe as ever... (Score:5, Insightful)
We just need to invest some time and money building new nuclear plants that aren't based on 1950s reactor designs.
Would you have bought a diesel car 30 years ago? Not unless you were a taxi driver. Would you even give petrol a moment's thought today? No chance!
Re: (Score:2)
Re: (Score:3)
We're getting electric and hybrid cars faster than diesel.
One of the problems with diesel in the US is the lack of supply, kind of like the natural gas cars in europe.
Diesel is less taxed in europe, at least in France, where it is significantly cheaper than regular gazoline. In the US diesel is actually more expensive than gasoline most of the time. A lot of people would probably destroy their diesel engine as well. I saw a few people put gasoline for their diesel during my time in europe, at best the car w
Diesel?!? (Score:5, Insightful)
Some very young people on here. And I'm showing my age.
A couple decades ago some bright people at the Big Three noticed diesel fuel was far less expensive than petrol (gas) - it was only used by transport and construction companies.
As a byproduct of refining petroleum it was underutilized and in ready supply - produce millions of gallons of lighter hydrocarbons from the mixture that is raw petroleum and you will have lots of it. Something few people consider is that Petroleum is a homogeneous mixture of hydrocarbons from the very light, such as C8, to the very heavy (depending upon the source) Asphaltics, C40 to 70. Fractional Distillation of a barrel of raw petroleum produces a wide range of potential fuels and other compounds.
So the Big Three shifted to production of diesel automobiles, promoting them as less expensive to operate. Consumers purchased them and then the darnedest thing happened, the price of diesel fuel went up! I mean, seriously, just because there's an increase in demand a price shouldn't go up, right?!? Well that seemed to be the prevailing logic.
Reduce dependence upon nuclear fuel for power plants and that energy will have to come from somewhere - Hydro? Solar? Wind? Geothermal?
Never, ever suggest using less energy, though. That could lead to Socialism (or even Communism, as detected in lab mice.)
Re: (Score:3)
It didn't help that all the big three diesels were complete shit either.
Re: (Score:3)
Reduce dependence upon nuclear fuel for power plants and that energy will have to come from somewhere - Hydro? Solar? Wind? Geothermal?
So I read a few Wikipedia pages and am now an expert.
The first post was right: the breeder reactors in question are based on pretty much the oldest nuclear technology available, which was meant to produce weapons-grade plutonium. These days there is a race to develop mini-reactors producing on the order of 100MW that can run for decades on depleted uranium (once the initial reaction begins) without refueling or requiring external power sources for cooling. Miniaturization is once again the future.
That is
Re:Diesel?!? (Score:5, Funny)
t "use less energy" by making it expensive... is that it tends to result in a lower standard of living -
Only if "high standard of living" means driving an SUV on a 1-hour commute from a poorly insulated mass-produced McMansion to an over-heated office lit by glowing wire filaments suspended overhead.
Re: (Score:3)
You can't put diesel into a car designed for unleaded petrol, since the nozzles are smaller. You can put petrol into a car designed for diesel, though. The only reason that unleaded nozzles were made smaller was so that you wouldn't accidentally put four-star into the tank instead of unleaded.
Re: (Score:3)
My Dad still drives his diesel VW rabbit on a daily basis. 50mpg from 1981 - it kinda makes a Prius look stupid.
Re: (Score:3)
We had the gawdawful Mercedes turbo diesel which because it was the most common diesel on the road, it single handedly kept any other diesels (other than pickups and larger vehicles) off the roads until now.
I'm glad to see diesels coming back. Old technology, better MPG, and it will become more interesting when diesel hybrids start hitting the showrooms.
Re: (Score:3)
Over in the US you didn't have some of the really dreadful diesels like the Ford York diesel, and the really rather pedestrian Landrover 2.25 that powered very nearly all the Black Cabs until a couple of years ago.
But we did have the rather under-developed GM passenger diesels that set back acceptance of the technology for decades. And "dreadful" would be a good description. It did have a rather advanced anti-tailgating feature . . .
Re: (Score:3, Insightful)
Re: (Score:3)
I call BS
the problem with diesel in the US has been its high sulfur content, which can truly bugger up all of the sensors on a turbo diesel in a couple years
Swede has offered ultra low sulfur diesel since 1990, it only became widely available in the US since 2007, on;y as a result of action by the EPA
the petroleum industry would have kept the sulfur in, since it is cheaper to produce, if it had not been for government regulation
I learned some new facts, my opinion changed (Score:3)
I disagree with your argumentation and interpretation of the poll.
We just need to invest some time and money building new nuclear plants that aren't based on 1950s reactor designs.
Would you have bought a diesel car 30 years ago? Not unless you were a taxi driver. Would you even give petrol a moment's thought today? No chance!
I thought that the question included all those 1950's reactor designs, because they're all still operating? I hadn't realized how many are built right on top of active faultlines, so my opinion about nuclear has seriously gone down.
I think nuclear energy is very unsafe at the moment. Aging reactors which are kept open using some nuclear version of ducttape, because it's completely unaffordable to dismantle them, are a growing risk.
It's also a
Re:Seems just as safe as ever... (Score:5, Insightful)
Re:Seems just as safe as ever... (Score:4, Informative)
I voted less safe, even though I agree new nuclear plants are certainly safe enough for me to support them, and here's why: I wasn't aware that Japan, one of the richest countries in the world, was running 40 year old reactors in the first place. I am surprised they screwed up with the generator location, and didn't recognise or fix the problem until now. I am surprised that this quake and tsunami was able to do the damage it did to the nuclear reactors, given that a tsunami hits Japan every six years on average, and everyone in the world knew that a big earthquake was on the cards.
So the current state of nuclear is less safe than I would have thought.
Re: (Score:3)
they messed up by putting the diesel generators the wrong place.
That's kind of the point, isn't it? These plants have the potential to cause mass death, and we're counting on every engineering decision being perfect. From this incident we learned something about the placement of the generators. What are we going to learn from the next incident? My point is we can't rely on trial and error here.
Re: (Score:3)
Gas and coal fired power plants have the potential to cause mass death, should the fuel stores on site catch fire. Oil refineries can blow up and kill lots of people. Buses and planes can crash, so can individual cars. About the only power sources that don't have the potential to catch fire are wind and solar. Solar panels do have a good bit of cadmium, usually.
Should we stop using everything that has a rather rare, once in a hundred or thousand year chance of causing the loss of a life?
Re: (Score:3)
Re:Seems just as safe as ever... (Score:5, Informative)
This is an incredibly important point that seems to have been missed. Well, two points actually:
1. Japan survived a magnitude 9 quake, one of the biggest ever, with barely a scratch. Buildings stayed upright and didn't become unsafe, damage was minimal and superficial. No trains crashed, the few fires were dealt with quickly and AFAIK not a single person died. From my hotel window I can see the brand new Tokyo Sky Tree, which is 634m tall, and it isn't even finished yet. There are still cranes on it, right at the time. Nothing fell down. Japan is about as earthquake-proof as it is possible to be, and these reactors shut down safely as designed.
The problem is the unprecedented tsunami which overwhelmed sea defences (that worked well against all the other tsunami over the years) and swamped the diesel generators, preventing proper cooling.
2. The amount of radiation is still very low and not considered harmful, except for at the power station itself. Even in the worst possible scenario where there is complete meltdown the contamination will not be spread like it was at Chernobyl because the reactor won't explode.
The situation is serious but not capable of developing into a major disaster.
Re: (Score:3, Interesting)
The cores are not the problem, the problem is the spent fuel. A spent fuel storage pool without water will spontaneously combust, and in the design of those Japanese reactors the roof above them is almost irrelevant (and after it's blown away by a hydrogen explosion completely irrelevant).
Re: (Score:3)
That is unfortunately completely wrong.
Three of the four reactors have significant amounts of old fuel rods stored on their roofs. One of those three has a huge amount stored.
In addition to those "roof storages" (you seem to misunderstand what that actually is) there is a "standard" storage pool on the area.
Re:Seems just as safe as ever... (Score:5, Insightful)
And yet, as far as I can tell, the media circus surrounding Japan has lasted for far longer than the one for Haiti.
Uh, Haiti was in the news constantly for weeks, and then intermittently for months after the earthquake. Japan is still in the news a few days after, but it's pretty early to be making this sort of comparison.
Funny how we care about (generally) rich Asians more than poor Blacks, isn't it?
You're the one that started ignoring the news about the poor blacks after a couple of days...
Re: (Score:2)
Re: (Score:3)
Fact: a concept whose truth can be proved;
Your post is inaccurate: FACT.
Actually, a "fact" is a statement about the world (universe) that can be tested. Upon testing, it can be demonstrated correct or incorrect. Don't make the mistake that a fact must be correct to be a fact; it can be incorrect and still be a "fact".
Let's take the first in the GP: "Global Warming exists FACT" This is a statement about the world and is testable. So even though there's a lot of debate as to whether it is correct or not and whether a natural cycle, it is classified a "fact".
Let
Re: (Score:3)
A 600 mile range on a tank of fuel isn't especially large - I get 500 miles per tank (40 litres) on my 1998 SEAT Cordoba Vario. My new car (a Skoda Superb that's being built now) is rated (manufacturer figures) to get anything from 490 to 730 miles on a single tank of fuel (60 litres).
Re:Seems just as safe as ever... (Score:5, Funny)
Re: (Score:3)
But that's due to bad engineering. What energy source can overcome that? Even with alternatives you need to store energy and that means the potential for rapid release, which is a disaster.
Godzilla (Score:3)
Re:Godzilla (Score:4, Insightful)
We have so many old reactors still active because after Three Miles Island and Chernobyl the peons panicked and blocked any new reactors from being built. In effect, the vast majority of nuclear plants active today were built before 1980.
In the meantime our energy consumption skyrocketed, coal and gas power plants simply do not have the capacity to replace nuclear. Not to mention that they are much more damaging to the environment than nuclear plants.
And don't get me started on green energy. It's wonderful, until you realize you'd need to cover the entire surface of the US with windmills to provide enough power to replace nuclear, coal and gas.
Re:Godzilla (Score:4, Insightful)
Your last line is complete B.S. and gives clear evidence that you don't know the science behind green energy but rather the political memetics spewed by pundits. Anyone watching the science knows its easily feasible. Brazil is over 80% powered by 'green energy' and yet they are not covered in windmills. I'll wait while you go google up Brazil's energy infrastructure and some pundit sputem to attempt to rebuke what I said. I won't be digging up all the scientific pubs, but take this as warning that they're out there.
Re: (Score:2)
1) Not highly relevant. The difference is not so drastic, especially so as to mitigate the point.
2) They generate their energy from hydroelectric, not solar, so I"m glad to have helped you with your now obvious ignorance.
3) They use sugar ethanol largely for cars. And yes, over 80% of energy supply is from hydroelectric.
You could at least watch a documentary on modern brazil or something before ramming your foot so far in your mouth.
Re: (Score:3)
Wow, jooceman watched a documentary, and now he is an expert
Well to be fair he did pwn AuMatar completely.
Perhaps the most serious objection is his dismissal of the importance of being in the sun-belt. After all the the ethanol Brazil uses comes from relatively (relative to maize that is) efficient sugar cane, a sun belt crop.
... and, just to bring this back on topic, if memory serves me correctly, at least a little of this Brazil's "80% green" energy is nuclear.
Re: (Score:3)
Initially, I thought that dropping the control rods stopped the reaction almost instantaneously.
Then I read that in Japan the problem they are having is that it takes time for the reaction to stop after the reactor is shut down, thus the slow partial meltdown they are going through.
Then, to respond to this, I checked Wikipedia on scramming and it says that it is almost instantaneous.
So now I'm just confused.
Either way, I
Re:Godzilla (Score:5, Interesting)
I thought that dropping the control rods stopped the reaction almost instantaneously.
Control rods control only the primary reaction; splitting Uranium atoms by knocking them with neutrons. Fission is, however, rather messy. When an atom splits it becomes two or more different elements. Those elements are typically weird and unstable isotopes (atoms) that then spontaneously decay (regardless of the state of the control rods) again and again until they reach some (relatively) stable state. Unfortunately this takes some time and each decay event radiates energy which creates more heat. When someone says dropping the control rods stops the reaction it is implied that only the primary reaction is actually halted; the byproducts of that reaction continue to decay spontaneously.
This is why the reactor continues to produce a lot of heat immediately after scram. The amount of heat radiated after scram is sufficient produce the catastrophe we see today. Cooling must be provided to prevent this.
Either way, I would have thought that they could and would have shut down the reactors a long time ago, like, while the tsunami was on its way or even when they realized the pumps were flooded.
The reactors scrammed immediately with the earthquake. As you should now understand this isn't sufficient to safe the reactor; cooling must continue for days after scram. This is usually done with 'off-site' power supplied by another power plant. That wasn't available because of the earthquake. Backup power generation should have then provided sufficient power to cool. This equipment was incapacitated by a huge tsunami that appeared about ten minutes after the earthquake. Batteries are then expected to provide temporary power. Batteries die.
Now we have achieved the condition known in the reactor business as 'blackout.' No off-site power, no backup power. No power means no circulation and no cooling.
At this point you're stuck. The reactor is overheating and overpressure. You must release pressure to keep the reactor vessel from rupturing (because a nuclear powered radioactive steam explosion is undesirable.) Releasing pressure means releasing coolant. Coolant loss exposes fuel. Exposed fuel overheats and causes a chemical reaction that produces clouds of pure Hydrogen. The Hydrogen accumulates someplace until it burns (blows up.) The explosions do fun things like put your staff in the hospital (15 so far) and knock out the fire pumps you've rigged up to supply coolant to the reactor (4 of 5 on Monday.) Equipment failures and mistakes continue apace as usual but now you have no margin for error; when some valve fails during normal operation the operators have an array of responses. A valve failure or inadvertent actuation during a blackout means you expose the core, as happened late Monday.
Meanwhile a spent fuel pool in an otherwise safely shutdown reactor (#4) catches fire due to lack of circulation and contaminates the site with enough radiation to sterilize mammals. The damn island won't stop moving either. Several times a day a 5+ aftershock tests every piece of equipment you care about. The tsunami wiped out most of the out-buildings where you kept the tools and spare parts you might have used to fix things. Folks show up with various forms of emergency power generating equipment, but it's all the wrong voltage, phase or current capacity so it doesn't just hook up; you go into engineer mode and decipher 40 year old technical material to get it wired up. Anything you break is irreplaceable. Turn your back and generators run out of fuel.
Did your family survive the waves? They were only a few kilometers inland...sure would be nice to leave and find out. Oh, wait.
To the pole question; my opinion hasn't changed about the safety of nuclear power. It isn't safe. It is, however, worth it. That some risk should accompany great power seems fitting. Japan salvaged itself from a ruined militar
Re: (Score:3)
To the pole question; my opinion hasn't changed about the safety of nuclear power. It isn't safe. It is, however, worth it. That some risk should accompany great power seems fitting.
Power, [wikipedia.org] in general, [guardian.co.uk] is dangerous. [wikipedia.org]
Pick your poison.
Re: (Score:3)
The opposition to nuclear power isn't just about danger, it is about nuclear non-proliferation and the debatable problem of spent nuclear fuel and contaminated waste.
Without going into the waste issue non-proliferation seems like a good idea. Unfortunately the only other non-renewable options are coal and gas, both of which have their own major problems. Renewable, on the other hand, could potentially deliver all the energy we need once sufficiently developed and without massive changes to the landscape or
Re: (Score:3)
No power means no circulation and no cooling.
Does anyone here know why the power plants are/were not designed to use the stream pressure to drive the cooling pumps? I mean mechanically, with a steam turbine connected directly to the pump shaft. No need for lots of electrical power, and the hotter the core gets the more power you have to pump.
I'm presuming there is a good reason why it isn't practical, because it seems like an otherwise rather obvious thing to do.
Re:Godzilla (Score:5, Insightful)
You might also be surprised how many fairly old aircraft are in use. Non-engineers tend to think that things inevitably wear out and have to be replaced, but that isn't necessarily the case. Aircraft can be flown indefinitely and safely as long as they are maintained correctly, and similarly so can nuclear reactors. What tends to take them out of service is parts and skills becoming harder to get or the on-going cost of maintenance making buying/building a new one a better option.
As for nature Japan has proven itself to be fairly earthquake proof - few if any buildings collapsed in the quake. I am in Tokyo at the moment and when it hit I never felt scared at all, despite being on the 5th floor of a tower block. Buildings moved (as designed) but there wasn't much damage and it didn't seem that big of a deal at the time. What did all the damage is the tsunami and there is now a lot of discussion about what can be done to defend against them in the future. Japan has sea defences because there are regular tsunamis, just none this big. I'm sure that in time this country will be as well protected from large waves as it is from large earthquakes.
Re:Godzilla (Score:5, Insightful)
As seen on reddit & facebook. (Score:5, Insightful)
"a 41 year old nuclear reactor gets hit by a 9 magnitude earthquake, then slammed with a 2 ft. tall swell, followed by an explosion due to the buildup of hydrogen gas that blows off the roof of the building, and the core is intact and contained. And you are telling me nuclear power isn't safe?"
Anyway... I wish Tritium cycle nuclear power would start getting some R&D
Time to retire the Uranium & Plutoniums reactors
Re:As seen on reddit & facebook. (Score:4, Informative)
"2 ft." should be "20 ft."
(yeah yeah...I mean 7 meters)
Re: (Score:2)
Due to the severity of the event, we forgive the failure of the secondary containment. What is not is the lack of coolant. If just the generators has failed, ok. But to say there is no way to manually inject water to prevent meltdown is not ok. In engineering we exp
Re:As seen on reddit & facebook. (Score:5, Informative)
Yes, but the problem at Fukushima is the residual heat from the still decaying by-products of the primary reaction (think Strontium, Cesium, Iodine) that continue produce heat. This will always happen and continuing to run the primary coolant through the stopped reactor is the only way to keep it safe until those by-products finish, usually weeks after the reactor has been stopped. If you want to know more about what happened at Fukushima, (http://bit.ly/h9Mwz0) is a layman's guide.
The newer Generation III+ reactors have solved most of the issues with this older design. Things like ensuring that the primary coolant loop will be gravity run in the event of failure, storing the extra coolant above the containment unit instead of below, etc. As long as the laws of physics still apply, we should be good.
Nuclear power has one of the top safety records (compared to other heavy industries and fossil fuel generation) but the whenever a disasters occurs, the public fail to focus on how the failsafes worked, or how the engineers did the right thing. The misinformation spread around by the fear mongers is the biggest danger to the public since power companies have been unable to build newer, safer reactors since the 70's. Power demands haven't gotten lower; they've increased and the demands we have put on the government to ensure lower carbon emissions and reduce pollution is going to make it difficult to continue with the more traditional fossil fuel based generators. None of the renewable methods (solar, wind, tidal, and geothermal) are ready for prime time and simply cannot take over for our power needs.
Missing Option: Safer than houses and buildings (Score:2)
Re:Missing Option: Safer than houses and buildings (Score:5, Funny)
its the exact same shithole it was in the 1980's when I was a kid
That's not true at all. It's far worse now than it was in the 1980s.
Fukushima plant was hit by an enormous disaster (Score:5, Insightful)
It was not human error, it was not a faulty design. It was one of the largest earthquakes and tsunamis recorded in recent history, and the largest event to EVER hit a nuclear plant. The fact that the reactors did not suffer a catastrophic meltdown yet is a testament to how reliable and ultimately safe nuclear technology is in Japan, but also to how dedicated the engineers working there truly are. My thoughts go out to those people that as we speak are inside the plant, trying to maintain a constant flow of water to cool the reactors in spite of the radiation and dangers. Like the soldiers in Chernobyl, they truly are heroes.
Bear in mind the Fukushima plant is built on the ocean side, and took the full force of the earthquake and the tsunami. There are risks inherent to nuclear reactors, but those engineers have shown that good designs and responsible usage can limit damages even in the face of an unprecedented force of nature. Even with the outer buildings blown to pieces radiation leaks have so far been minor, and the reactor containers are intact.
I thank them on behalf of the world, I wish I could be there to help.
My poll choice is irrelevant, but I hope all the nuclear plants in the world are at least as well built and manned.
Re: (Score:3, Interesting)
It was not human error, it was not a faulty design.
Maybe not human error, but willful negligence, the kind that we see happening in our country all of the time which makes me not want to take a chance on nuclear power.
Japan's deadly game of nuclear roulette
http://search.japantimes.co.jp/cgi-bin/fl20040523x2.html [japantimes.co.jp]
Re: (Score:3)
Even with the outer buildings blown to pieces radiation leaks have so far been minor, and the reactor containers are intact.
Radiation levels up to 400 millisievert per hour were recorded outside the plant yesterday. This is not minor. 6 Sievert is a sure lethal dose, so 15 hours exposed to this level of radiation will kill you. And the emergency is not over. I'm afraid it hasn't really started yet. I don't even want to think about what happens if a radioactive cloud moves towards Tokyo.
400mSv an hour would be a high dose. Funny thing about radiation is that as you get further away from the source, it tappers off. So if it is 400 mSv-h at 10 feet from the reactor, at 20 foot away it should be down to 20mSv-h (i hate inverse squares). The good thing is, the IAEA is not saying that the 400 mSv reading is constant, just that it was a single time reading, and that further readings in the area are down from 11mSv-h to 0.6mSv-h. http://www.iaea.org/newscenter/news/tsunamiupdate01.html [iaea.org] So yes, 40
Can be safe, but safety engineering is hard (Score:3)
While I still like the idea of building more nukes, this incident makes me more interested in understanding the failure modes of the "tried and tested" designs both in plants and on the drawing board for new plants, and whether they are susceptible to the same problems should the active cooling system fail, whether due to natural disaster, sabotage/terrorism, or just plain bad luck.
Re: (Score:2)
Unfortunately this is the case for pretty much any nuclear power plant in current operation. Safer [slashdot.org] reactor designs do exist but it seems to me like the massive investment that was required to research and build the old reactor designs coupled with the massive cost and risk of disassembling them has held back progress on adoption of the new technology anywhere it could be used to replace existing reactors. Sad.
Re:Can be safe, but safety engineering is hard (Score:5, Insightful)
One reason that people are working to maintain adequate cooling is because a meltdown puts the containment shell to the test. This is a test that it should handle with ease as meltdown temperatures are around the 500C mark and the shell can withstand over 2000C, but it would still be better not to have to test it at all.
Another reason is that a wrecked core is a significant financial loss - in terms of the core, all the useful material it still contains, and the difficulty of cleaning it up. If cooling is maintained perfectly then everything can be saved. Even by resorting to sea water for cooling (which makes the core permanently unusable) the system can be cleaned up easily, and the fuel can be reclaimed.
Of course people are still evacuating and for a very good reason. An unparalleled disaster has just wiped out all the backup facilities necessary for a clean shutdown. There is now the potential for a meltdown, which means that the last line of defense (the containment shell) would be tested. As reliable as containment shells have proved to be there is simply no point in taking risks.
Thankfully the work done to maintain cooling means that the meltdown may still be averted, and it is also giving people time to evacuate just in case there is a meltdown and a (very unlikely) containment failure.
Re:Can be safe, but safety engineering is hard (Score:5, Insightful)
So there is no risk associated with letting the reactor melt down, and yet they decided to vent radioactive gas anyway? And then, they took the step of using seawater to cool it down despite the fact that the reactor is essentially destroyed after such a corrosive material comes into contact with it, but they "needed" to do that instead of letting it "Safely melt down"? I doubt they trust the reactor shells nearly as much as you do, Mr armchair nuclear engineer.
Re: (Score:3)
While the GP is downplaying the seriousness of the accident your post does not really make a good argument.
Nuclear safety usually follows a protocol known as "defense in depth", which pretty much means you don't rely on a single line of defense. Thus even if the containment would be sufficient to contain a meltdown, you'd also do whatever you can to prevent it from reaching that stage in the first place. This may involve venting to release pressure, or cooling with seawater.
Now obviously there has been a lo
Too Early to Tell? (Score:2)
The plants are still exploding and threatening to melt down.
About the same - still no excuse not to push solar (Score:2)
Re: (Score:2)
By the time we run out of uranium and thorium, we'll have developed fusion power. Or something even better.
Solar is cost effective in the equatorial deserts of the world, but it won't replace fossil fuels until we have a global superconducting grid. Space PV won't be cost effective (or even implementable) for a long, long time. We need something that can replace fossil fuels *today*. Vast areas are turned into wastelands and thousands of lives are lost every year due to the mining/extraction process. M
Re: (Score:3)
You can build reactors (the designs are already known and tested) that burn up the waste material produced in other reactors, and also produce fissile material of their own.
You can also reprocess the fuel from old reactors, but the US does not do this any more for political reasons, and simply stores spent fuel, uselessly.
Re: (Score:3)
Uranium is not rare. Uranium is more abundant than Tin. Thorium, another viable nuclear fuel, is even more abundant, and is about as common as Lead. It will take a long, long, long time for us to even come close to depleting those.
Well statisically you could say it's less safe (Score:2)
Just like the Concord was made "less safe" by a single crash on its permanent record. I still wouldn't hesitate to hop on board if it was still in service.
The united states needs to build more plants (Score:4, Funny)
media and politics (Score:3, Informative)
I've not changed my opinion on the safety of nuclear technology, in fact the waste disposal still seems to be the bigger problem with the technology.
However, it has strengthened my view on our (german) politics. Since this week, I honestly believe our government should be in jail and/or shot. Let me explain:
In 2000, the then government passed a law limiting running times to 32 years for all reactors, which would've put our country at 2021 as the date of the last one being shut down. Most of them would've been offline a lot earlier, as the majority of our 19 nuclear power plants is from the 70s.
Last year, our current government changed that law, removed the years and replaced them with power generation limits, i.e. each reactor can produce a remainder of X MWh of electrical power before it has to be shut down. Serious calculations now put us at around 2032 until the last one is offline, and some of them will have been running for almost 50 years. In addition, many safety regulations were losened or removed, and remaining power amounts can (under conditions) be transferred between plants. Which means some of them might be running a lot longer/older.
So our government didn't like their predecessors "out-of-nuclear-energy" plan, but they didn't have the guts to take a stand. We now have some of the oldest, least safe reactors on the planet, and we'll be having them for another 20 years at least.
My thought on reactor safety: It's a technology that has the potential for catastrophic impact when things go wrong. If you play with safety here for reasons of profit or political power, you are pure evil.
About sums it up... (Score:5, Insightful)
I was discussing this on IRC, and someone pretty well summed up my feelings in regard to people saying stuff like "The plants weren't safe enough", etc etc
"It's like shooting someone in the face with a tank and saying bulletproof vests are useless"
BWR popcorn turns out not to be an issue (Score:5, Informative)
I voted seems slightly safer because BWR popcorn was not an issue and that has always been a huge design concern with BWRs.
I strongly considered going into nuclear engineering, but did not. Anyway one thing I learned in my studies, before I said F it and want into electronics, is BWR design is an unholy PITA because of this scenario:
Chugging along at full power, something happens, for example, one of the strongest earthquakes in recorded history.
Steam valves to the turbines shut off. Wham.
Now a normal BWR reactor runs a void coefficient of like 15%. That means 85% of the core has yummy water moderator and 15% has (more or less) no moderator just steam which makes that bit of the core quite non-reactive. Mixing is very important to prevent fluid boiling and literal oscillation under normal conditions.
Suddenly, with no place to go because the valves slammed shut, the pressure spikes. That collapses all the steam bubbles and you now have a void coefficient of ZERO.
That means your moderator effectiveness goes from, perhaps, 85% to 100%. Meaning a huge spike in reactivity. Now a reaction in the center of a fuel rod takes a heck of a lot of time to thermally conduct to the surface, so the reactor has an insane power spike before enough water can boil to shut down the reaction.
Eventually the thermal heat from the insane spike either vaporizes the fuel rods and literally blows them to bits, or conducts heat into the coolant making the worlds biggest steam explosion. Either way, "BWR popcorn" little bits of reactor all over the countryside about one or two seconds after the steam valves slam shut. Its not entirely like what happens when a old fashioned american tank style water heater blows up, except about a thousand times bigger, sorta.
Now there are numerous safety features to work around this. Staggering amounts of fluid dynamics and thermodynamics and strange hydraulic things and computer automation to prevent this. Control rods that slam in place faster than the steam valves can shut. Crazy condensation/ventilation systems. Exotic coolant pumps to control circulation. I know the Japanese have a fondness for BWRs and when I heard none of the BWRs popped like a popcorn kernel a few seconds after the quake, I figured they were home free.
The current crisis is "just another decay heat meltdown" combined with plenty of flaming zirconium fun. Could happen at any ole reactor, PWR, BWR, any fission reactor without coolant. Zirconium is a really great fuel rod cladding from a nuclear properties standpoint, but when it gets hot and water hits it, it acts exactly like sodium, hot hydrogen gas is generated and that pops the pressure relief valves, collects "somewhere" and goes boom. Maybe after this fun we'll switch to something a bit less reactive even if it is less efficient. Kind of like graphite is a really awesome moderator other than that pesky "fire" phenomena (and having to anneal it, which lead to a nice fire in the UK in the 60s, long before Chernobyl)
Its strange but true, that once you react and literally blow up all the zirconium, assuming the containment vessel holds, which it almost certainly will, all the excitement is over. The goal is numerous small zirconium hydrogen explosions that are all individually too small to crack the containment, not one big ole whopper that cracks it open.
Re: (Score:3)
I don't get why they let it explode.
All they have to do is leave a pilot light on when they vent it, and it'll burn like a torch instead of explosively. Provided they can get a pilot light to work in that case.
And if it's got a chance of exploding, why not just vent it to the air? It's going to end up there anyway, when it explodes.
What really blows my mind is the incredibly stupid cooling-system design that depends on another vulnerable system, the generators, to run. Gravity-fed or steam-driven would se
Irresponsible Journalism (Score:5, Insightful)
The media has been horrible, at least in Canada and the US. They seem to only be able to sell stories and get ratings by trying to scare people. If you look at various other outlets, you see very different reports of what is actually going on, and what the situation is.
I was totally disgusted that the CBC up here in Canada last night aired a program that was sensationalistic to begin with, and then on top of that brought in an "expert" to comment about want was happening to the power station in Japan. The "expert" was the head of an anti-nuke lobby. Seriously. Unbelievable. That's some responsible balanced coverage let me tell you.
Re: (Score:2)
i'd feel safer if there wasn't such a history of cover-ups - PR seems to underestimate the ability of the public to understand issues. or maybe it got us sized up very well and thought cover-ups were still apt?
that's just me.
i still feel, however, that it's a fair bit safer than people give it credit for. Chernobyl was a very, very unsafe design (RBMK). almost cynically unsafe - like the Russian government cared more for it's weapons program than it's citizens. the BWR's have some safety to them - consi
Re: (Score:3)
Re:Safer than I thought (Score:5, Insightful)
But it's all been contained. There's only been one death (getting crushed by a crane) and one significant radiation poisoning (the guy will almost certainly live). And that was the result of what was really the worst imaginable scenario. Everything that could go wrong, did. And the casualty count stands at two. Maybe it will get worse. Maybe more people will get sick. But it is highly unlikely that it will even get as bad as the Deepwater Horizon disaster. In fact, comparing the two shows just how safe nuclear tech is:
Deepwater Horizon - caused by cost cutting and ignoring safeguards.
Fukushima Daichi - caused by a 8.9 magnitude earthquake, 20 foot tall tsunami, and numerous 6.0 magnitude aftershocks
Deepwater Horizon - Platform was new, modern
Fukushima Daichi - Plant was 40 years old, about to be shut down
Deepwater Horizon - 11 immediate deaths, many workers sickened during cleanup
Fukushima Daichi - 1 death, about a dozen showing signs of possibly getting sick, none terminally
Deepwater Horizon - Vast swaths of the Gulf floor coated in inches of oil, killing all life there.
Fukushima Daichi - Environmental impact yet to be determined, but if it's similar to Three Mile Island, it will be non-existent
Deepwater Horizon - People (rightfully) point out that we don't abandon airplanes just because they occasionally crash
Fukushima Daichi - People demand the end to all nuclear power
People are just irrationally frightened of all things nuclear. I suspect it's a holdover from the Cold War.
Re: (Score:3)
A strange definition of "safe" you have here. Sure, it is not yet as bad as in Chernobyl, but that doesn't mean that it won't get worse. In Chernobyl it was only one reactor block, here we have four with critical problems, and major cooling problems in the remaining two. Two big holes in the wall of block 4, fires in a storage for fuel elements, buildings of reactor blocks 1 and 3 destroyed by explosions (who is the idiot responsible to build these things in a way that hydrogen could emerge?), containment o
Re:Safer than I thought (Score:4, Informative)
You are comparing two completely different plant designs, and fearing that they might be the same. To use /.'s perennial car analogy, it would be like fearing to own a car because sometimes large gas refineries have fires.
Chernobyl used a graphite moderated system, where big graphite rods were inserted between fuel rods to cause the reaction to slow down. If you know chemistry, you know why that would only work up to a certain temperature and work better without any available oxygen (graphite = carbon, kinda like charcoal, for those who don't). So, once Chernobyl got hot, and someone realized that they needed to slow the reaction down, it was a bit late as the whole thing was so hot that the control rods could catch fire. Without the control rods, that were now on fire, the reaction could speed up again. Daiichi/Daini plants are not built using a system anything like that. In all that I have seen, none of the reactors have lost the main containment. #1 reactor, the one that everyone is sealed. "Meltdown" doesn't mean anything more than "the fuel got hot enough to melt." It's not a good thing, but it doesn't equate to a disaster movie at all. It was still completely contained, the last report that I read. #4 might have had some secondary or tertiary containment breach, but it wasn't operational at the time of the shutdown, and wasn't producing as much heat or radiation. My understanding there is that the contaminates weren't expected to spread far from that breech.
As for the radiation numbers, you are panicking over the word 'radiation' and 'contamination' for no good reason. A CAT scan gives you 1 to 20 mSv dose of radiation, while the expected normal dose from all natural sources (sunlight, food, stars on the other side of the galaxy, uranium in the dirt of your lawn, radon in your basement) over a year is about 1 to 3 mSv. If you work with just getting 9mSv from a CAT scan over 15 minutes, you have gotten exposed to a radiation source that is emitting more than 300,000 times a 'safe yearly dose per hour' (math may be off, it's early). Secondly, radiation is like heat; it may be really hot to put your hand in the fire, but the room around the fireplace is comfortable. The problem that is more concerning in general is contamination from fuel or 'hot' isotopes of iodine. Since the reactors still have containment, this isn't really a problem right now. If they lose containment, it might be; that depends on how it happens. A simple crack in the containment buildings would not spread any contaminants beyond the immediate area; while a fire would release it in smoke.
Now, for dose numbers. If, inside the reactor buildings, the radiation really is 400 times more than a years dose per hour, then the radiation at a distance of five miles is going to be detectable but not high. You wouldn't feel a camp fire from 5 miles away, and radiation works the same way. Now, you could detect that camp fire if you had a very sensitive device that was designed for detecting very small temperature variations. In this case, it turns out that radiation detectors are that sensitive, and very small problems on one side of the globe can be detected on the other side (governments paid to make them that sensitive so they could spy on each other doing nuclear tests underground). For the workers at the plant, they have devices called dosimeters, and are only allowed to work for a limited amount of time, just to control how much radiation they receive. Those safety devices may keep a worker who was in the plant from going back in, just to keep their lifetime exposure below an acceptable limit.
You misunderstand some things (Score:3)
Sir,
You have some of your facts wrong. A "moderator" in a nuclear reactor slows the neutrons down so that they interact more effectively with U235 or another fissional isotope that likes "slow neutrons". Normal fission neutrons have MeV's worth of energy and don't interact well with fissionable isotopes so the reaction won't go without a moderator.
BWRs and PWRs are normally moderated AND cooled with water. Water doesn't absorb neutrons very much, so they remain available to i
Re: (Score:3)
For what ever reason, in the back of my mind I believed that Chernobyl had both a graphite moderator and graphite control rods; because of that, I did specifically say that it was a graphite moderated system, using moderated in the common parlance instead of the technical term. Hard to tell in text, but I was attempting to explain it in common terms. Should I have also explained the difference between the moderator and the control rods? Should I have explained the use of a second water loop in a PWR as oppo
Re:A lot less safe than I thought (Score:4, Insightful)
A single backup? They had multiple diesel generators, batteries, and a mechanism to quickly hook up mobile generators. They also had the ability to bring seawater in for cooling.
Re: (Score:2)
As I understand the situation, there are only two cooling systems. The first was destroyed by the earthquake, the second by the tsunami. That leaves nothing but pouring in sea water manually, which has been insufficient so far to prevent three explosions and a rupture of the vessel.
Re: (Score:3)
No, there are plenty of redundant systems - pumps, pipes, and other methods to cool the reactor but they are running out of options.
There are several ways to run the pumps or cool the reactors in the event of a scram:
* offsite power from another power station (infrastructure destroyed by massive earthquake)
* diesel generators (many of them, not just one or two) - destroyed by massive tsunami
* battery power - will run the pumps for 8 hours, until an alternate source of power can be found, or fresh batteries
Re: (Score:2, Insightful)
It is importtant to note that the current nuclear reactors were built using active cooling systems but if you look at the generation III reactor design, which is what current reactor designs are based on, it incorporates passive cooling system that use natural convection instead of a pump.. Also note that even given a complete meltdown and failure of the cooling system, the reactor would still contain the radiation since the nuclear reaction can't possibly reach a temperature great enough to penetrate the c
Re: (Score:3, Insightful)
I learned a nuclear plant requires active cooling
Yes, it requires active cooling to shutdown cleanly, as in be fit for starting up again in the future.
When the main cooling fails en the backup fails, everyone is screwed.
Not at all. When the cooling fails you get a meltdown, which the containment shell is designed to contain. There is nothing wrong with a contained meltdown as far as safety is concerned. The problem with Chernobyl is that there wasn't a containment shell, and uncontained meltdowns give meltdowns a bad name. The other problem is just the cost of cleaning up the sealed ball you are left with, anything less th
Re: (Score:3)
Designed, maybe, but it's not like anyone has ever been able to test it in a situation as bad as this. Three Mile Island was a partial meltdown because they deactivated their cooling systems in an emergency situation. The containment worked, but only because they brought the cooling back online in time. No one knows what would have happened if the cooling system hadn't come back into play. In Japan the coolin
Re:A lot less safe than I thought (Score:5, Insightful)
"a nuclear plant requires active cooling" is not true. "Very old types of nuclear plants require active cooling" would have been better.
Re: (Score:2)
Re: (Score:2)
a 41 year old nuclear reactor gets hit by a 9 magnitude earthquake, then slammed with a 2 ft. tall swell ...
Two foot?! Might want to fact check there dude.
Re: (Score:3)
I answered "safer", because I am astounded at how much of a beating that whole facility has taken and it's still holding its own quite well.
I'm willing to bet they could fly an airliner into one of the containment buildings and it would STILL remain safe, even now.
I did learn the afore-unknown-to-me detail that the reactor requires as much cooling as it does post-scram. So I suppose that decreases to some degree my faith in that particular reactor design. But still, seeing the beating it's managed to hold
Re: (Score:2)
If you ever need proof of how mindlessly pro-nuclear the Slashdot crowd is, just look at the 26% ...
Wow, an absolute majority ... no wait!
Re:Bias (Score:4, Insightful)
Or maybe you've got a one-way view of what that 26% represents....
It *could* mean people who have witnessed a gigantic earthquake, tsunami, failure of cooling systems, multiple explosions --- and after 3 days of DREADING onslaught, the actual reactors have not melted down or exploded to produce the radiation that many are in fear of.
So maybe 26% of the people viewing the poll are surprised it could do so well considering the events.
(preemptive strike: i voted 'slightly less')
Re: (Score:2)
So yeah, it *is* a lot safer than I thought it'd be... It's still holding, even if barely.
Re:Bias (Score:5, Insightful)
Deepwater Horizon didn't need any natural disaster to cover an area the size of Ireland in toxic, carcinogenic chemicals.
The fact that primitive nuclear reactors could survive a magnitude 9 earthquake and 20-foot tidal wave at all shows that newer, better designs in safer locations are practically indestructible.
Re:Bias (Score:4, Insightful)
I live less than 40 min away from one, its nice to know that that even IF it was on a fault line and hit by one of the top 5 earthquakes ever recorded THEN a tusnami, that 1940's engineering would survive with minimal damage and leakage
mindless,no, not I... I feel safer knowing that a properly maintained facility can survive one of the biggest "shit hits fan" real life scenarios with minimal in this case exposure
learn some basic math, run the numbers, and get over 1986 cbs fear mongering over piss poor Russian design ran by a bunch of flunkies who run a stress test with non functional equipment
Re:Bias (Score:5, Insightful)
Who modded this up?
Ah, I must have missed the news of where, after being hit by a 9.0 magnitude earthquake, and a 20-ft wave, the 40 year old plant completely wiped out everything within a 50 mile radius. Link please?
When you consider the magnitude of the catastrophe, it *is* impressive that the site is as under control as it is. Despite all of the media hype about the imminent doom, things seem to be holding up remarkably well. Not great, but certainly not the end of the world, and frankly the least of Japan's problems right now. And hey, so far it seems like the long-term damage from the reactors will probably be way less significant than the Deepwater explosion in the gulf. Nuclear power *is* safer than the media portrays it. And certainly modern nuclear plants are safer than these older ones.
As an aside, applying a single trait to an entire group like /. is fairly silly. Slashdot isn't pro-apple, or pro-google, or whatever; nearly every article on any topic has tons of comments on both sides. Try not to make wide generalizations about things simply because you read opinions you don't like.
Re: (Score:3)
Nuclear has it's problems, all right. The thing is that if there is a problem with nuclear, it tends to involve quite some people killed and a large area around the plant contaminated (think Three Mile Island, Chernobyl).
The problem with burning coal and oil is that this are much slower and more silent killers. Air pollution caused by such plants kills thousands of people every year - more than nuclear kills; possibly more than nuclear even per kWh of power generated. Coal burning also causes global warmin
Re:Bias (Score:4, Insightful)
I would hope a coal plant wouldn't burn. Coal is radioactive. Running a coal plant releases orders of magnitude more radiation into the environment than a nuclear plant. I also wouldn't like to see what would happen when that nasty, nasty fly ash stored on site was washed away by a tidal wave. Where would it end up?
Coal power stations are seriously unclean, radiation spewing things. Nuclear plants produce nuclear waste, but it is contained. Coal plants produce *millions of tons* of fly ash along with all that radiation, that gets piled up outside the plant.
And your assertion that they have to take "special measures" to "avoid another exclusion zone like Chernobyl" is just total FUD (and you're the one claiming "zealotry"!). These reactors will not fail in the way Reactor 4 did at Chernobyl - an RBMK reactor operating outside of its safety zone with all of its safety systems intentionally disabled, and crucially not enclosed in a containment structure, that suffered a catastrophic steam explosion (it did not melt down until afterwards) that blew the top off, and surprise surprise, with no containment, exposed the core.
These reactors in Japan are contained, and at any time the operators can simply "abandon" them by draining out all of the water (so no more steam or hydrogen buildup) and allow them to melt inside their containment structures. It will make them more expensive to dismantle afterwards (hence the attempts to maintain active cooling so they can decommission it more cheaply and quickly afterwards) but if they run out of options they can leave them to melt safely within their containment, keeping all the radioactive material inside.
The fact that these containment systems have already survived a 9.0 earthquake and many powerful aftershocks with no damage should probably tell you that they were built with extreme conditions in mind, and with a single job: to isolate the core from everything else.
This whole "it will be like Chernobyl!!! zomg!" nonsense is like standing outside an airport and protesting modern commercial passenger flights by holding a sign that says "No more Hindenburgs!!!!"
Re: (Score:2)
It fascinates me that we use nuclear power, to generate steam...to generate electricity. It seems a long way to go, to do something they figured out how to do in the 1800s. When you're a little kid and you hear 'nuclear power', you think...the nuclear aspect actually generates power. There should be more energy efficient means of doing it. Especially by now. I think this really demonstrates how much Big Oil and Big Energy have held back our technology. You can't find much else (besides cars) that is still using the same methods and fundamental technology 100 years later.
The power companies actually are well motivated to find better ways of converting heat into electricity. (Heat being the main product - the explosion in a nuclear weapon comes from super-heated matter expanding). Steam remains the most practical means, so far. Significant advances have been made in converting steam to electricity. As for Big Oil, well, if people are paying less for their electricity, they have more money for travel, which is, by far, primarily powered by oil derived fuels. Big Coal has some
Re: (Score:3)
It fascinates me that we use nuclear power, to generate steam.
BTW, steam power is quite useful. In fact, somebody built a steam powered prosthetic arm that uses hydrogen-peroxide as its fuel: http://technoccult.net/archives/2009/04/06/steam-powered-prosthetic-arm/ [technoccult.net]
Re: (Score:3)
Well, perhaps (as Japan has illustrated) nuclear is not ideal for the shaky isles, without a lot of extra work on safety and contingency planning.
In contrast, your big brother to the west is relatively stable, with lots of room and reserves of uranium. I would think we would be a great fit for nuclear power except for (1) entrenched interests in the coal and power industries, (2) NIMBYs, and (3) lack of control over corporations leading to skimping on design, build and maintenance by the operators.
Breeder reactors. (Score:3)
There is no long-term waste disposal problem. It isn't like the power grid can only accept Uranium electrons but not Thorium ones. We have had the technology for most of the nuclear age to keep using the fuel until we have got almost every bit of useful radiation out of it.
http://en.wikipedia.org/wiki/Breeder_reactor [wikipedia.org]
They became politically unpopular because they can be used to generate material useful for nukes. But in the hands of first world nations I am not really concerned about Al Qaeda breaking in and
Re:No Change -- Still Bad (Score:4, Insightful)
Or, you know, we could just use that waste as fuel, in reactors we know how to build *right now* but don't do so for political reasons.
Storing it is just silly - it would be like refining oil to get gasoline and then storing all of the kerosene, diesel, propane, methane etc that also comes off in giant barrels and burying it in the desert.
Nuclear power is crippled by an image problem, by misinformation, and by ludicrous red tape.
Re:No Change -- Still Bad (Score:4, Informative)
Mod up, the waste takes 100,000 years to become inert.
Know what you call material with a half-life of 100,000 years? Not radioactive. It's the stuff with half-lives measured in years, days, minutes, and milliseconds that you don't want to be around.
Re: (Score:3)
Iodine 131 is a completely different beast to Iodine 129.
Iodine 129 is used as a biological tracer to monitor nuclear pollution, since it doesn't occur in nature It's extremely long half life means it's unlikely to decay in your lifetime. I131 has a half life of a scant eight days, making it nearly 700 million times more likely to decay inside you, so for a given amount of each isotope (both of which decay by high-energy beta), you'll receive 700,000,000 times more radiation from 131 than 129 in a given tim
Re: (Score:3)
I remember as a child (back around 1970) ...
Well there's the problem. Ever thought that you mis-understood, mis-heard, or mis-remembered?
Re:Japan braces for a potential radiation catastro (Score:4, Informative)
10x normal levels ... Normal level is for Tokyo, say, 2mSv/Yr.
10x that is therefore 20mSv/Yr.
50mSv/Yr is the normal background level of radiation in some parts of the middle east, India and Europe.
100mSv/Yr is the lowest level at which any increase in cancer is clearly evident.
Thanks for mentioning 3 Mile Island. There was one case [bbc.co.uk] despite people like you claiming many, many more.
Why should I believe you anyway, since you already admitted to a propensity for lying when it comes to describing radiological events?
Do you think if that was a hazard government officials would be honest about it, up front, right after a disaster? I wouldn't be