Chernobyl

[tbroye]

In light of what is going on in Japan with it's reactors here is a site about Chernobyl. This is by a young I think Ukarian women who rides her motorcycle through out the former Soviet Union. She has done a lot of photo essays on Chernobyl and give a different perspective on it that was given by the Soviets or any news organizations. Chernobyl was a Military Reactor the made Plytonium for weapons, Electricity was a by product and was of a different construction than those in the USA or Japan, ececpt for the one's at Hanford. If you can find the link for ghost town that is the first story, she may of changed it by now.

www.elenafilatova.com

 

[workinforwood]

It's a sad situation. I'm all for nuclear power too, I think it's a very good resource. I think they should build them under the ocean maybe. I'm sure that wouldn't be easy or cheap, but no lack of cooling, that's for sure.

 

[jttheclockman]

The one word answer is FUSION

That is where the minds need to concentrate.


http://www.diffen.com/difference/Nuclear_Fission_vs_Nuclear_Fusion

 

[bbarter]

very interesting but sad as well

 

[Kaspar]

Hanford was shut down over 20 years ago, though the memory (and a few other things) linger on.

Chernobyl was an interesting fusion (no pun intended) of Russian operational incompetence with a poorly designed and engineered plutonium breeder reactor that would never have been licensed to operate anywhere in the West. It didn't even have a containment shell. The test they'd scheduled and the cascade of stupidities that followed are a lesson in how not to run a nuke plant.

It took the fourth most powerful earthquake recorded, a 30 ft. tsunami that took out their back-up generators and, so far, five days and counting, to bring the Japanese to brink of anything vaguely like Chernobyl. If they can get those cores cooled down without losing containment, I'd say that's a win for the safety of nuclear power.

(The latest, though, is that it's looking pretty bad. One fire is controlled, but they're having to pull everyone out now.)


JTTClockman: Fusion? Wake me when it works.

And then tell me how much a kilowatt hour it's going to cost. I'm very dubious about whether they'll ever be able to make fusion work within a capital cost per megawatt of capacity that's even remotely reasonable.

Tokamaks involve mammoth cryogenically cooled magnets and world-class vacuum pumps, among other things. Laser or particle beam implosion requires a large number of very high power lasers or "non-trivial" (an engineering term meaning "fuggedaboutit- you won't live to see it") particle accelerators (and the above world-class vacuum pumps).

It's hard to see how such a plant could be built at any kind of reasonable price, not to mention how one avoids immense operating and repair costs. Acceptable "Mean Times To Failure" in a laboratory / research facility won't cut it in an operational environment. (Try to imagine how long CERN would last if it had to run 24 hours a day.) Even assuming free fuel, the amortized capital cost and ongoing operating cost may well make the power generated unfeasibly expensive. I'm not willing to pay $20 per kilowatt-hour for electricity; the 0.0291 cents per KwH I'm paying now is fine with me.

The best bet for the near term is Thorium-type Nuclear Reactors. They've got a tough plumbing problem to solve still, but I think they're close. Nicest thing about them is that they can reprocess the spent fuel right on site and turn all that nasty cesium and strontium back into uranium. Much easier to store and not too dangerous. Hikers will walk over hundreds of tons of the stuff in their lifetimes.

Anyway, glad you asked. :biggrin:

 

[azamiryou]

I'm fairly skeptical of the information available about what's going on with the reactors in Japan. The media have a definite sensationalism bias - "Oh my god, we're all going to die! Tokyo is going to be irradiated and uninhabitable for generations!" The nuclear scientists and engineers have a conflict of interest, since their livelihoods depend on the acceptance of nuclear power.

The scientists and engineers may be down-playing the risks a bit, but from everything I've seen, their take seems very reasonable.

Here is one site with a fairly simple explanation of what's going on and the real risks. As with everything else, it's worth taking it with a grain of salt, but it makes good sense to me with my engineering and science background.

http://bravenewclimate.com/2011/03/13/fukushima-simple-explanation/

One thing I don't understand: the plant can't generate power to operate its own cooling system because the main reaction has been stopped. But clearly, there is still a lot of heat there - why can't they use the residual heat to power a small generator capable of keeping the cooling system running?

 

[monophoto]

The scientists and engineers may be down-playing the risks a bit, but from everything I've seen, their take seems very reasonable.
- - -
One thing I don't understand: the plant can't generate power to operate its own cooling system because the main reaction has been stopped. But clearly, there is still a lot of heat there - why can't they use the residual heat to power a small generator capable of keeping the cooling system running?

As an engineer who devoted an entire career to all aspects of electric utility system planning, I understand the issues involved here. And based on that understanding, I am inclined to believe that we have yet another example of where the panic of the situation makes it difficult to get a clear picture of everything that is going on, and the tendency of the media to interpret any kind of uncertainty as absolute proof of either imminent disaster or conspiracy and corruption is only aggravating the situation.

As to utilizing the unwanted heat - interesting idea, not not gonna happen. The plant lost both its normal grid connection (and plant auxiliary system) and the emergency off-site power connection. The tsunami flooded out the batteries used to start the emergency diesels. Therefore, there is no source of start-up power needed to start circulating water through the reactor and turbines.

 

[moke]

In light of what is going on in Japan with it's reactors here is a site about Chernobyl. This is by a young I think Ukarian women who rides her motorcycle through out the former Soviet Union. She has done a lot of photo essays on Chernobyl and give a different perspective on it that was given by the Soviets or any news organizations. Chernobyl was a Military Reactor the made Plytonium for weapons, Electricity was a by product and was of a different construction than those in the USA or Japan, ececpt for the one's at Hanford. If you can find the link for ghost town that is the first story, she may of changed it by now.

www.elenafilatova.com

Tom--
Thanks for posting this....it is very interesting.

 

[wolftat]

I would be fine with all utilities being shut down and letting everyone fend for themselves. I believe they refer to then as the simpler times.

 

[azamiryou]

As to utilizing the unwanted heat - interesting idea, not not gonna happen. The plant lost both its normal grid connection (and plant auxiliary system) and the emergency off-site power connection. The tsunami flooded out the batteries used to start the emergency diesels. Therefore, there is no source of start-up power needed to start circulating water through the reactor and turbines.

Thanks for the insight. I was wondering more about the design of the plants, not the operators' actions in this case. Why don't reactors include a small generator that can run on the residual decay heat and keep the cooling system running?

 

[monophoto]

As to utilizing the unwanted heat - interesting idea, not not gonna happen. The plant lost both its normal grid connection (and plant auxiliary system) and the emergency off-site power connection. The tsunami flooded out the batteries used to start the emergency diesels. Therefore, there is no source of start-up power needed to start circulating water through the reactor and turbines.

Thanks for the insight. I was wondering more about the design of the plants, not the operators' actions in this case. Why don't reactors include a small generator that can run on the residual decay heat and keep the cooling system running?

Technically, it certainly would be possible to design a power plant to function the way you suggest. But that small, auxiliary power plant that you are proposing would have to be designed with 'black start' capability. A thermal power plant requires a great deal of electric power to operate its auxiliaries in order to start up. The basic design premise is that start-up power can be taken off of the grid. So the issue of 'black start' is viewed as a system issue rather than a plant-specific issue, and most systems rely on either hydroelectric plants or gas turbine plants to provide black-start power.

The way these designs are done is that engineers sit around imagining the unimaginable, and then integrating solutions into the design to address those contingencies. In the case of nuclear plants, this process is aided by regulatory agencies that specify minimum requirements. But ultimately, every design is based on a premise that all practical contingencies have been accounted for, and therefore it is unlikely that conditions would ever come along that fall outside the assumptions of the design. Remember that this earthquake was more severe than any previous earthquake in Japan, and the fourth most severe in recorded history (two of the recorded instances of more severe earthquakes occurred prior to construction of this plant).

This plant is 40 years old. It was state of the art at the time it was built, and incorporated the latest thinking about the level of contingency planning that should be considered as discussed in the article you cited. Fukushima 1 went on line in 1971. The Indian Point 1 plant outside New York City went on line nine years earlier, but was retired only three years after Fukushima was commissioned because its emergency cooling provisions didn't meet the standards that had come into effect during that period.

I don't disagree that your idea of a black-start auxiliary turbine generator that would extract unwanted heat from the core to prevent a dangerous temperature rise would be an additional layer of contingency planning. Adding additional layers of contingency protection doesn't necessarily make systems more reliable - eventually, you reach a point where the additional complexity introduces new modes of failure. What has actually happened in the nuclear industry is that newer reactor designs have evolved that don't require active cooling, and therefore don't require multiple layers of protection to deal with that heat.

I don't disagree that this has been (and for the people of Japan, continues to be) a horrible experience. But it's important to put this into perspective. The most severe industrial accident in recorded history was not a power plant failure - it was a chemical accident in Bhopal, India. And the most severe catastrophes in history have been caused by natural disasters. When the final numbers are known, I suspect that there will be more fatalities from the earthquake and tsunami in Japan than from the Chernobyl disaster. And who can forget the earthquake-induced tsunami in December 2004 that killed almost 300,000 people.

 

[azamiryou]

Thanks for the detailed info. It makes some sense to me now.

 

[bybill]

As to utilizing the unwanted heat - interesting idea, not not gonna happen. The plant lost both its normal grid connection (and plant auxiliary system) and the emergency off-site power connection. The tsunami flooded out the batteries used to start the emergency diesels. Therefore, there is no source of start-up power needed to start circulating water through the reactor and turbines.

Thanks for the insight. I was wondering more about the design of the plants, not the operators' actions in this case. Why don't reactors include a small generator that can run on the residual decay heat and keep the cooling system running?

Technically, it certainly would be possible to design a power plant to function the way you suggest. But that small, auxiliary power plant that you are proposing would have to be designed with 'black start' capability. A thermal power plant requires a great deal of electric power to operate its auxiliaries in order to start up. The basic design premise is that start-up power can be taken off of the grid. So the issue of 'black start' is viewed as a system issue rather than a plant-specific issue, and most systems rely on either hydroelectric plants or gas turbine plants to provide black-start power.

The way these designs are done is that engineers sit around imagining the unimaginable, and then integrating solutions into the design to address those contingencies. In the case of nuclear plants, this process is aided by regulatory agencies that specify minimum requirements. But ultimately, every design is based on a premise that all practical contingencies have been accounted for, and therefore it is unlikely that conditions would ever come along that fall outside the assumptions of the design. Remember that this earthquake was more severe than any previous earthquake in Japan, and the fourth most severe in recorded history (two of the recorded instances of more severe earthquakes occurred prior to construction of this plant).

This plant is 40 years old. It was state of the art at the time it was built, and incorporated the latest thinking about the level of contingency planning that should be considered as discussed in the article you cited. Fukushima 1 went on line in 1971. The Indian Point 1 plant outside New York City went on line nine years earlier, but was retired only three years after Fukushima was commissioned because its emergency cooling provisions didn't meet the standards that had come into effect during that period.

I don't disagree that your idea of a black-start auxiliary turbine generator that would extract unwanted heat from the core to prevent a dangerous temperature rise would be an additional layer of contingency planning. Adding additional layers of contingency protection doesn't necessarily make systems more reliable - eventually, you reach a point where the additional complexity introduces new modes of failure. What has actually happened in the nuclear industry is that newer reactor designs have evolved that don't require active cooling, and therefore don't require multiple layers of protection to deal with that heat.

I don't disagree that this has been (and for the people of Japan, continues to be) a horrible experience. But it's important to put this into perspective. The most severe industrial accident in recorded history was not a power plant failure - it was a chemical accident in Bhopal, India. And the most severe catastrophes in history have been caused by natural disasters. When the final numbers are known, I suspect that there will be more fatalities from the earthquake and tsunami in Japan than from the Chernobyl disaster. And who can forget the earthquake-induced tsunami in December 2004 that killed almost 300,000 people.

Modern Pressurized Water Reactors (PWRs) have steam driven emergency cooling pumps that are driven by the residual heat. Well at least the plant that I am intimately familiar with (Seabrook in NH.)

I don't understand why they couldn't connect the portable generators they brought in. They must have electricians and linemen that could get them working.

I feel that they didn't realize the severity of the mess they were in and dragged their feet. It could be a lack of emergency planning or just a difference in culture. Here in the US protection of the health and safety of the public comes first and the plant is secondary.

In case you are wondering I have a degree in Health Physics (radiation protection) and 25+ years in civilian (mostly) and Navy nuclear power, and I make a pen now and then

Bill

 

[Nate Davey]

A good write up here from MIT.

http://mitnse.com/2011/03/13/why-i-am-not-worried-about-japans-nuclear-reactors/

 

[crabcreekind]

i found the answer. perpetual motion machine. that unlocks all answers to the universe

 

[Smitty37]

Wher????

Hanford was shut down over 20 years ago, though the memory (and a few other things) linger on.

Chernobyl was an interesting fusion (no pun intended) of Russian operational incompetence with a poorly designed and engineered plutonium breeder reactor that would never have been licensed to operate anywhere in the West. It didn't even have a containment shell. The test they'd scheduled and the cascade of stupidities that followed are a lesson in how not to run a nuke plant.

It took the fourth most powerful earthquake recorded, a 30 ft. tsunami that took out their back-up generators and, so far, five days and counting, to bring the Japanese to brink of anything vaguely like Chernobyl. If they can get those cores cooled down without losing containment, I'd say that's a win for the safety of nuclear power.

(The latest, though, is that it's looking pretty bad. One fire is controlled, but they're having to pull everyone out now.)


JTTClockman: Fusion? Wake me when it works.

And then tell me how much a kilowatt hour it's going to cost. I'm very dubious about whether they'll ever be able to make fusion work within a capital cost per megawatt of capacity that's even remotely reasonable.

Tokamaks involve mammoth cryogenically cooled magnets and world-class vacuum pumps, among other things. Laser or particle beam implosion requires a large number of very high power lasers or "non-trivial" (an engineering term meaning "fuggedaboutit- you won't live to see it") particle accelerators (and the above world-class vacuum pumps).

It's hard to see how such a plant could be built at any kind of reasonable price, not to mention how one avoids immense operating and repair costs. Acceptable "Mean Times To Failure" in a laboratory / research facility won't cut it in an operational environment. (Try to imagine how long CERN would last if it had to run 24 hours a day.) Even assuming free fuel, the amortized capital cost and ongoing operating cost may well make the power generated unfeasibly expensive. I'm not willing to pay $20 per kilowatt-hour for electricity; the 0.0291 cents per KwH I'm paying now is fine with me.

The best bet for the near term is Thorium-type Nuclear Reactors. They've got a tough plumbing problem to solve still, but I think they're close. Nicest thing about them is that they can reprocess the spent fuel right on site and turn all that nasty cesium and strontium back into uranium. Much easier to store and not too dangerous. Hikers will walk over hundreds of tons of the stuff in their lifetimes.

Anyway, glad you asked. :biggrin:

Where are you getting electricy for .0291 cents per Kwh? I pay 14.4 cents Kwh average.