nuclear power plants and long term power outages

I live about 50 miles from a nuclear plant. As you read about solar flares maybe knocking out the entire states power grid, or an emp pulse from some type of nuclear weapon exploding I want to know exactly what will happen at our nuclear plants with absolutely no power. I have been to several sites, and as I try to understand the explanations, I still do not understand what will happen. The sites all talk about backup generators kicking on and keeping the coolants (water) pumping stopping the plants from causing problems. BUT if we have no power backup generators etc what will happen and will the plants "meltdown?" I know I am showing ignorance here that's why I am reaching out to you guys to get some true information on what would really happen. Looking forward to your responses!! I

I use to live close to a Nuclear plant but no longer thank goodness. However I do have friends that live near one and have wondered the same things myself. An M Flare would take down some grids for sure and the plants had better be ready. Not sure what kind of backup generators they would use - it would be good to know. I noticed when I lived near the plant if you ask questions its difficult to get straight answers - they don't want panic in the neighborhood. They just give you those little pamplets - you can read them in the bathroom while contemplating what to do if SHTF.

Most corporations ,miltary and government run installations run diesel generators for power but they only last 8 hours and more fuel required,refuelling if you get the drift,after which meltdown.So the Powers that be will have 8 hours to tell you to get the hell out of there..

reply to post by crazydaisy

Yeah My mom and I have been arguing about this for 2 days. She thinks that if the power goes out the plants just sorta shut down and the water coolant will cool the rods and everything just stops. But that is not what the sites state. First they would have to have those back up generators to keep the coolant flowing. well if the pulse takes out all power I assume that means generators also. In that case the sites states that the coolant would over heat and the water would start to evaporate eventually exposing the rods. This would produce lots of uncontrollable radioactive steam, and I assume once the core is exposed then it "melts down?" I am trying to understand this so in this kind of event I would know whether I need to move my children north. Anyone else have any info????

reply to post by gringoboy

So generators will run after an emp pulse? I was under the impression nothing like that would work??What do you think?

Come on guys. With all the intelligent people here someone has this info on how this actually would go down. Someone out there has worked at a plant or has an understanding of how one operates. Let's get this info out as it could effect lots of peoples lives. Many have not even given this a thought in their survival preparations.

The magnetic latches or special motors holding the control rods should release and drop.
This will dampen the reaction.

Most water cooled reactors also have a boron quench tank that is gravity feed to the reactor.

This is all covered under a reactor SCRAM(safety control rod axe man)
en.wikipedia.org...

The first nuclear actually had a safety control rod axe man. some guy with a axe to cut the rope holding the control rods up.

So the rod would be contained in this liquid and stop the reaction? Even without fresh coolant being pumped into it? so I am understanding that the reaction would stop and we would not suffer any fall out ect from this plant? Correct me if I misunderstand your explanation and thanks for replying!

I am pretty sure that as long as the generators are not on when the EMP hits they should be fine.

Giving you a good 8 hrs (probably more) to get the hell out of dodge.

Its a valid question and not ignorant at all. I have worked in the industry for 20 years so maybe I can help. By federal law, 10CFR, all nuclear plants must have redundant safety systems. The emergency generators are the same type used to power locomotives or ships. They are huge and one can easily handle all the needs of the site. All sites have at least 2 of the generators plus a smaller back-up one and fuel to run them for many days. As soon as in coming power is lost, the reactor automatically shuts down, The generators then power the pumps that cool the reactor. Soon everything will have cooled and the reactor is in "cold shutdown" There is plenty of water on site to replace any lost to steam. The entire system is enclosed and can be managed easily in this condition.

Turkey Point Nuclear Plant in Florida lost all in coming power for two weeks during hurricane Andrew I believe it was and they were fine, never any danger of overheating. For an extended power outage fuel can be trucked in to keep the generators running indefinitely. Also, the people that staff these plants are some of the brightest, highly trained folks you will ever meet. Hope this helps, be happy to try to answer any questions you have.

reply to post by tinkytink1207


It appears the concern is what kind of fuel do the generators use and how much fuel do they have stored at the plant. In other words from the time the grid goes out and the generators take over how long do you have before the rods are exposed? Either way after a year I was happy to move away from the plant I was near - only 1 mile away and I felt the stress everyday. If you could call the plant or have someone else do it and ask questions maybe they will answer you outright - if not and you are able to move further away then you will have that decision to make with your family.

Afterthought - some online research might help answer the question as to the generators and fuel.

reply to post by tinkytink1207


I ironically and weirdly actually know the answer to this question. Not sure how to feel about that lol, but yes the Generators should still run after a EMP pulse as they are not electrical but rather run by gasoline, but I am not 100% sure on that. I think that a EMP pulse only works on running electrical things and generators only run after they are started. I could be wrong though.

However, moving on to your question about the power plants. I actually watched this National Geographic special called Aftermath Population Zero. It was a very informative and interesting special all about what would happen if all humans just vanished from existence at once. Anyway it went into power plants and basically if the power failed the generators would run for 1 to 2 weeks on the gasoline in the generators. After the generators died the rods would begin to heat the water, and once the water evaporated give another 2 weeks the then the building would begin to burn from the inside out and result in basically a Chernobyl effect.

You can find the video for free online just a matter of looking. It is very informative and interesting I suggest anyone that is big on survival it is interesting to find out what happens. It goes into animals and the way buildings break down etc. Hope this helps.

reply to post by tinkytink1207


On the event of power grid dropout, all nuke plants are designed to automatically idle down to a safe operating state. That is what happened to many nukes when we had the north eastern blackout.

When the grid has an unplanned dropout, it forces the nuke plant to go into emergency shutdown. That is because it is impossible for it to change operating power point that quickly. So the reactor heat is dumped and the turbines are spun down.

Most nuke plants do not have the ability to self start. That is, come up to operating condition from a blackout. They need to pull energy off the grid to bring everything up to operating conditions and synchronize to the grid to come on line.

There is a few nuke plants that have diesel generators big enough to allow it to do a cold start. But the concern for most is a safe shutdown.

The ability has been tested time and time again, resulting from unexpected power glitches and blackouts. Considering that there has never been a failure of that shut down system, I would say that you don’t have to worry about it.

Originally posted by tinkytink1207
reply to post by gringoboy

 

So generators will run after an emp pulse? I was under the impression nothing like that would work??What do you think?

Diesel works by a different compression ratio than petrol generatrors and does`nt require spark plugs for ignition,in short a manually crank can start all diesel generator regardless of emp burst.otherwords the soldier takes a wrench and ..you get the drift but usually military cranks are a massive weight that fall with the force of gravity to start compression.hope that answers your query.

Pardon my ignorance but why can't nuclear plants just continue to run on the juice they create, with some kind of dump if the grid can't handle the output?

I will let someone else answer this as it is above my knowledge. I will wait and see what others say. Thanks for replying.

Good we are finally getting some good information here. So basically if something happens we have at least 2 weeks or more before anything major would happen - such as at Chernobyl. That makes me feel a bit better but with grids affected all over what is it going to be like to transport fuel and people to safer locations (I guess that's another story). In countries with lots of plants, is there a safe place - okay I am frightening myself again, sorry.

Originally posted by sligtlyskeptical
Pardon my ignorance but why can't nuclear plants just continue to run on the juice they create, with some kind of dump if the grid can't handle the output?

They need generators because they cannot be interferred with once started unless the building gets nuked or compromised in another mad way .

So a few feel that there is not a lot of concern as these generators will keep it going. But if there is no way to refuel the generators( no trucks able to run the petro etc) then we would have a problem in about a week to two weeks? I want to make sure I am understanding what everyone is saying so I would not overreact in this type emergency. So if we are looking at a full blown outage that lasts for lets say months would you guys feel we would need to evacuate the nuclear area?

reply to post by tinkytink1207


If there was a situation where the grid was going to be out of a long time and they couldn’t get diesel fuel to the plants, or get them started on grid power, then they would have to defuel the reactor. Basically pull the fuel rods and put them in the storage pond. That would be the easiest way to put the plant into a long term storage condition. They could easily do that before the fuel ran out for the generators.

The other way is if it was close to another coal plant that can come up without grid power, and you was able to get a working circuit between them, then they could use the coal plant to bring the nuke up to where it can run under it’s own power, and let it idle there. Basically, get the nuke plant back on it’s own two feet and leave it alone.