Be glad you don't live in Japan Friday

[Linkster]

So far what has been found by the American teams that are on-site there is that NO reactors have been damaged - most of them didnt have fuel in them anyway at the two sites the news has been covering.

The real issue is that the fuel they took out of those reactors some time ago has to sit in pools called spent fuel pools to keep them covered.

At one plant the spent fuel pool was damaged and all water is gone out of the pool (including the boron that is normally in the pool dissolved in the water) and they have no way to get any water back into it right now - there is no fire associated with that.
A second spent fuel pool is looking like it also was damaged and lost its water - but that is not certain yet.

The explosions and fires that have reduced the other buildings to rubble are not the reactor buildings - they are called auxiliary buildings and house the backup equipment on the outside of the reactor building.
All reactor buildings are intact with the exception of the one above that has no water in the spent fuel pool - that building has lost its last boundary and the dose rates from direct radiation from the fuel is very high.

The US NRC did take the precautionary step of evacuating all US citizens for 50 miles outside the confirmed damaged aux building today.

Remember also that the news is talking about nuclear plants without even telling anyone that this is actually two different sites in different cities

The fires after the hydrogen explosions (gas explosions which are non-radioactive) have been caused by the flammable oil storage tanks and the oil in the pumps being used to try to get water to the spent fuel pools.

[Bill]

Why does the sciam page say that the seawater/boron mix damages the reactors?

What happens to the seawater pumped into the reactors? Presumably afterwards it contains some amount of contaminant, possibly at dangerous levels.

[Linkster]

The stainless steel used to line the reactors will be destroyed by the chlorides (salt) in the seawater which will make the reactors unusable in the future = with the temperatures and pressures that a reactor operates at, the corrosion levels from salt can eat through stainless in a matter of hours

[Linkster]

Bill - also as far as I know, no one has even come close to pumping boron or seawater into any of the reactors - the seawater cooling approach was only going to be used for the spent fuel pools (storage for old fuel) - I have not been able to find any reliable sources that say that there was ever a lack of water in any of the reactors and it would have surprised me if they had lost any water in those designs

[Linkster]

Just an update - the spent fuel pools I was mentioning earlier have been confirmed to have water in them (which is great news) and while the temperature is a little higher than normal its not anything that cant be controlled easily.

All of the other reactors are doing fine and are shutdown and cooled down - at both plant sites in Japan - with the exception of one unit (#3) at the Daiichi site that is currently being sprayed from copters with cooling water to control the temperature and avoid damage to the reactor.

[tickler]

I still like the ideal of these mini-nuclear plants!

$25 million, 20,000 homes. at about $0.10/kwh, and the size of a garden shed!

Self-contained units, factory built, not major security item, swappable modules, and can be used at location without upgrades to the grid.

http://www.physorg.com/news145561984.html

[Cleo]

I still think the huge concrete containment domes over US nuclear plants in the US, like the ones at Turkey Point south of me, offer far more protection than the secondary steel vessels around the Japanese ones. I know that I don't worry about the ones south of me and hope they go ahead with plans to add two more.

Originally Posted by tickler

http://www.physorg.com/news145561984.html

That look great but I'm not sure that the public would ever go for it.

[Toby]

Originally Posted by Cleo

...I don't worry about the ones south of me and hope they go ahead with plans to add two more.

The only issue I have with building more nuclear plants is the disposal of the spent fuel. They still haven't figured that out, and in the mean time, it sits in pools accumulating.

[Cleo]

Originally Posted by Toby

The only issue I have with building more nuclear plants is the disposal of the spent fuel. They still haven't figured that out, and in the mean time, it sits in pools accumulating.

I think there is already a solution, big hole deep underground, but the public won't agree on anything so as a result it sits in "temporally" pools.

[Bill]

The small format reactors are interesting, but I've yet to see really convincing working prototypes - has anyone else?

I thought the pebble bed reactor concept was interesting too.

As I understood it tho, uranium is the limiting factor for a nuclear electricity economy. There's enough uranium for a while, but of we wanted to produce planetary scale amounts of nuclear electricity the struggle for uranium would relatively quickly mirror the current competition for oil.

The proposed solution is a plutonium economy based on breeder reactors - and a plutonium economy has a lot of scary problems asscoiated with it.

[Linkster]

Originally Posted by Toby

The only issue I have with building more nuclear plants is the disposal of the spent fuel. They still haven't figured that out, and in the mean time, it sits in pools accumulating.

Actually most plants have instituted their own storage vaults on-site that gets the fuel out of the pools into a dry storage cask

[Linkster]

Originally Posted by tickler

I still like the ideal of these mini-nuclear plants!

$25 million, 20,000 homes. at about $0.10/kwh, and the size of a garden shed!

Self-contained units, factory built, not major security item, swappable modules, and can be used at location without upgrades to the grid.

http://www.physorg.com/news145561984.html

Unfortunately they fail to mention that if you had one of these in an earthquake of a magnitude of about 5 and up you would crack the concrete and have a worse dispersal of material than they have in Japan right now - and I tend to believe that Homeland Security would have some real issues with these

[JK]

I'm by no means an expert in nuclear power, and my country is responsible for a fair amount of natural atrocities that I have no control over (mining, burning coal, not to mention exporting uranium), but I watched a documentary a few months ago outlining the benefits of nuclear fusion, which sounds like a much cleaner energy source than fission, that has if I remember correctly no waste and an unheard of efficency ratio.

If you don't mind me asking Linkster, why isn't more money being spent on researching other types of nuclear power, rather than trying to fix a shit one, for lack of a better word. This is of course, based on my very limited knowledge on the subject.

[Cleo]

Turns out that the moon has a plentiful supply of helium 3 that I've read would make fusion practical.

[LD]

I too am intrigued by fusion. I had thought that fission was just a precursor to fusion. My concern is that big energy sources get somewhat institutionalized, like oil. It becomes very hard to progress to a better alternative, usually because of big financial stakes in the status quo. Oligopolies and monopolies have a way of digging in and become extremely resistant to change.

[Bill]

We are not significantly close to practical fusion as a commercial energy source. They've been stalled for a while. Inching forward with magnetic containment systems and laser ignition and other interesting technologies, but even if we crash poured trillions into development there's no reason to believe they will crack the problem.

You got the new "cold fusion" guys, but while one hears curious rumors it seems just as likely that's just a gimmick or a noncommercial effect, and nodody I know of in the energy industries is willing to say "well, we should look at it".

I always hoped for fusion too.

There are all kinds of interesting research projects going on - I keep hoping one or more of the promises will come to fruition. But year after year goes by and none of the promises makes it to the marketplace in any practical way.

Yesterday metafilter linked to the wave disk engine. Sounds great, right? Well over the years I've seen many such things that sounded great, but they never come to the market.

Magnetohydrodynamics for example - one of my all time faves - huge news in the energy community years ago - never came to anything.

Recently I saw an article about a carbon dioxide based supercritical fluid generator that sounded like it might be based on magnetohydrodynamics, or at least an improved phase-change turbine. Sounds great. An alternative to the steam turbine. Will we ever see it? I bet we won't.

[Linkster]

JK - fusion first of all is being researched heavily right now but the technology has not been refined enough to make it useful for probably at least 50 years - there is a group of countries right now pouring alot of money into the research in the ITER reactor project currently underway. The problem so far has been that all experiments have required more energy input to the reactor and systems than you produce. The ITER project has claimed that they believe they can produce power at 10 times the input power.

In answer to the amount of money being spent - more money is spent on fusion research than any other energy research currently

The concept that there is no waste to deal with is not true - you still have radioactive waste - the difference is that it decays in about 300 years (which is about the same length of time it takes the radioactive waste from a coal buring plant to decay) vs. the 10,000 years or so from the fission process.

The last issue is that most environmental groups and anti-nukes will have issues with the tritium that leaks from fusion reactors since it is even an issue right now in groundwater from many other industries including fission. Tritium is usally dismissed by most people as a harmless waste, however if you ingest it or absorb it through the skin it is much more damaging to the body than most other nuclides we deal with in fission plants - and tritium is very abundent in fusion

An example I guess I could make would be that if a fusion plant was located in Japan during the earthquake and flooding, you would have significant issues from the resulting magnet explosions, tritium releases etc that would probably kill way more people than anything all of these fission reactors will do....during Three Mile Island (which is the closest type of release compared to the Japanese plant releases) there were exactly 0 deaths caused and the risk of cancer rose by less than if each one of the people in Pennsylvania had smoked one cigarette

[RedCherry]

Saw this posted up on the current radiation levels that have been measured, and how long you would have to be exposed to to them to equal common radiation exposure.

http://www.cbryanjones.com/journal/2...n-english.html

[Linkster]

Thats actually an excellent comparison - although in the US we use a different (non-intl unit) measurement system which is in millirem and rem (1000 mrem = 1 Rem)

the micro sieverts he uses on the map equate to our units of measurement by using 1 mrem = 10 micro sieverts

The legal limit the nuclear industry workers in the US are allowed per year is 5000 mrem, although none come even close - the highest Ive ever received in one year is around 2000 mrem.

The natural background we see in the US at sea level is about 310 mRem per year - 40 mRem comes from your own bones (potassium is radioactive) and another 310 mRem from the average xrays, medical and commercial/industrial operations(smoke detectors, exit signs above doors etc etc)
If you happen to live in Denver you obviously would get more since you are closer to the cosmic radiation coming in from space - and flying gets you a little more each flight.

A good read for the US background is:
http://www.nrc.gov/reading-rm/doc-co...radiation.html

The levels outside of the worst damaged plant in Japan is somewhere between 2 and 4 mRem per hour if you were standing at the fence constantly.

In comparison - the worst radiation levels anyone was exposed to at Three Mile Island was at the fence and it was 1 mRem per hour - at the height of the accident - and then tapered off to background levels after a few hours. Of course the only people close to the fence were the news media and they had to be shooed away to make sure they didnt get that extra 1 mRem since they aren't evidently capable of learning anything about nuclear power

[tickler]

Originally Posted by Linkster

Unfortunately they fail to mention that if you had one of these in an earthquake of a magnitude of about 5 and up you would crack the concrete and have a worse dispersal of material than they have in Japan right now - and I tend to believe that Homeland Security would have some real issues with these

I'll have to take your expert advice on that, but I do believe that they are sealed metal units!

As far as Homeland Security, as mentioned in the article, you would have to break into the area, use heavy equipment to dig the unit up, break into the actual unit itself, and deal with a small amount of material that is "too hot(temperature wise) to handle" manually! People might just happen to notice this going on!

Also, the material is so low grade, you would need massive amounts, and massive technology to upgrade it!



I come from an uranium mining & processing part of the country, and radiation levels are constantly monitored! Studies show that nuclear workers tend to be exposed to about half the radiation as normal people!

Perhaps because of protective work gear, working in "shielded" areas, more caution about X-rays/CTs, etc.
http://www.brucepower.com/docs/Topic...ugust%2026.pdf

Actually in one small processing town, the cancer rate is lower than average population, and the cancer rate for nuclear employees working there is lower even than the rate for the town!


That sort of ties in with family history(living in a uranium mining area) where almost nobody seems to die from cancer, although there are the other normal medical problems! We just blame it on constant radiation theraphy from the slightly higher background radiation! There are some actual long term studies of my family being conducted about this effect!

[Linkster]

I'd have to see exactly what they submit to the NRC (if they ever do) to see the design but I tend to believe that some of their claims are already impossible (like no moving parts - when they say they use turbines to produce electrical energy - impossible to do with no moving parts)

They claim on their website that the unit is enclosed in concrete which is why I made the comment - also the uraniom that is used in the fission process wouldnt just be "hot" thermally - it would be instantly fatal if exposed to it - the enrichment figures they talk about are not much different than you see in a University reactor at colleges in the US.

The low level exposure studies are something Ive been following for a long time - seems that most researchers come to the conclusion that some small amounts of exposure are beneficial - while others claim that "any" exposure has a risk - seems kind of weird since the body is a source of radiation from the bones naturally (Potassium).

[Cleo]

With all the bananas that I eat I must be a radioactive hazard.

[Bill]

I kinda liked what George Monbiot had to say.

http://www.guardian.co.uk/commentisf...apan-fukushima

You will not be surprised to hear that the events in Japan have changed my view of nuclear power. You will be surprised to hear how they have changed it. As a result of the disaster at Fukushima, I am no longer nuclear-neutral. I now support the technology.

A crappy old plant with inadequate safety features was hit by a monster earthquake and a vast tsunami. The electricity supply failed, knocking out the cooling system. The reactors began to explode and melt down. The disaster exposed a familiar legacy of poor design and corner-cutting. Yet, as far as we know, no one has yet received a lethal dose of radiation.

Some greens have wildly exaggerated the dangers of radioactive pollution. For a clearer view, look at the graphic published by xkcd.com. It shows that the average total dose from the Three Mile Island disaster for someone living within 10 miles of the plant was one 625th of the maximum yearly amount permitted for US radiation workers. This, in turn, is half of the lowest one-year dose clearly linked to an increased cancer risk, which, in its turn, is one 80th of an invariably fatal exposure. I'm not proposing complacency here. I am proposing perspective.

If other forms of energy production caused no damage, these impacts would weigh more heavily. But energy is like medicine: if there are no side-effects, the chances are that it doesn't work.

Like most greens, I favour a major expansion of renewables. I can also sympathise with the complaints of their opponents. It's not just the onshore windfarms that bother people, but also the new grid connections (pylons and power lines). As the proportion of renewable electricity on the grid rises, more pumped storage will be needed to keep the lights on. That means reservoirs on mountains: they aren't popular, either.

The impacts and costs of renewables rise with the proportion of power they supply, as the need for storage and redundancy increases. It may well be the case (I have yet to see a comparative study) that up to a certain grid penetration – 50% or 70%, perhaps? – renewables have smaller carbon impacts than nuclear, while beyond that point, nuclear has smaller impacts than renewables.

Like others, I have called for renewable power to be used both to replace the electricity produced by fossil fuel and to expand the total supply, displacing the oil used for transport and the gas used for heating fuel. Are we also to demand that it replaces current nuclear capacity? The more work we expect renewables to do, the greater the impact on the landscape will be, and the tougher the task of public persuasion.

But expanding the grid to connect people and industry to rich, distant sources of ambient energy is also rejected by most of the greens who complained about the blog post I wrote last week in which I argued that nuclear remains safer than coal. What they want, they tell me, is something quite different: we should power down and produce our energy locally. Some have even called for the abandonment of the grid. Their bucolic vision sounds lovely, until you read the small print.

At high latitudes like ours, most small-scale ambient power production is a dead loss. Generating solar power in the UK involves a spectacular waste of scarce resources. It's hopelessly inefficient and poorly matched to the pattern of demand. Wind power in populated areas is largely worthless. This is partly because we have built our settlements in sheltered places; partly because turbulence caused by the buildings interferes with the airflow and chews up the mechanism. Micro-hydropower might work for a farmhouse in Wales, but it's not much use in Birmingham.

And how do we drive our textile mills, brick kilns, blast furnaces and electric railways – not to mention advanced industrial processes? Rooftop solar panels? The moment you consider the demands of the whole economy is the moment at which you fall out of love with local energy production. A national (or, better still, international) grid is the essential prerequisite for a largely renewable energy supply.

[Cleo]

Here is another one.

Fossil fuels are far deadlier than nuclear power.

I know that I would much rather live near a nuclear power plant that one that burns fossil fuel but unfortunately I live near the oil fired one at Port Everglades.

[Bill]

One of the interesting possibilities. I already mentioned that we don;t have enough uranium to power an economy long term - but the thorium proponents claim we have enough thorium.

http://theweek.com/article/index/213...ear-power-safe

+++++++++++++++++++++++++++++++++++++++++++++
Why are fans so excited about it?
Thorium-fueled reactors are supposed to be much safer than uranium-powered ones, use far less material (1 metric ton of thorium gets as much bang as 200 metric tons of uranium, or 3.5 million metric tons of coal), produce waste that is toxic for a shorter period of time (300 years vs. uranium's tens of thousands of years), and is hard to weaponize. In fact, thorium can even feed off of toxic plutonium waste to produce energy. And because the biggest cost in nuclear power is safety, and thorium reactors can't melt down, argues Michael Anissimov in Accelerating Future, they will eventually be much cheaper, too.

How cheap would it be?
If a town of 1,000 bought a 1-megawatt thorium reactor for $250,000, using 20 kilograms of thorium a year with almost no oversight, every family could pay as little as $0.40 a year for all their electricity, Anissimov predicts. And small reactors like that aren't just potentially cost-effective, he says; they're much safer, too.

Where can we get thorium?
Lots of places. The U.S. has an estimated 440,000 metric tons, Australia and India have about 300,000 metric tons, and Canada has 100,000 metric tons. Until recently, U.S. and Australian mining companies threw it away as a useless byproduct. There is enough thorium to power the earth for about 1,000 years, boosters say, versus an estimated 80 years' worth of uranium.

If thorium's so great, why do we use uranium?
To make a "long story very short and simple," says The Star's Antonia Zerbisias, weapons and nuclear subs. U.S. researchers were developing both uranium-based and thorium-based reactors in the Cold War 1950s, but thorium doesn't create weapons-grade plutonium as a byproduct. Plus, nuclear submarines could be designed more easily and quickly around uranium-based light-water reactors.

OK, but there must be a downside to thorium, right?
Indeed. First, it will take a lot of money to develop a new generation of thorium-fueled reactors — America's has been dormant for half a century. China is taking the lead in picking up the thread, building on plans developed and abandoned in Europe. And part of the reason Europe dropped the research, according to critics, is pressure from France's uranium-based nuclear power industry. Others just think the whole idea is being oversold. If "an endless, too-cheap-to-meter source of clean, benign, what-could-possibly-go-wrong energy" sounds too good to be true, says nuclear analyst Norm Rubin, it's because it is.
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