A nuclear power plant design for 1000Mw, 500Mw, etc... has been approved for build by the appropriate agencies...The plant can be built immediately or as soon as possible and would only require inspections and testing, and would not require a design submission.
The NRC has approved the AP600, they love it, and the AP1000 is simply a scaled up version. From what I hear at my workplace, the NRC now has a system in place to get plants up and running in 5 years or so, from a licensing standpoint. Most plants in the US are of Westinghouse design, so their work could be seen as a de-facto standard. Combined with potential federal loan guarantees for another 8,400 MW of nuke plants, and you may yet see nuclear construction in the next few years.
In terms of legal hurdles, the easiest way to expand the US nuclear fleet is to add reactors at existing sites. The local population is already quite used to living in the shadow of these plants, and will probably just see it as more jobs.
heheh kinda funny.. but it was said that DU munitions are only dangerous when it's coming at you at 3,200 FPS, and then any real or imagined long term health problems are largely irrellevent.
Never mind that also in said reactor, you don't have to shut it down for months to refuel it - new pebbles in the top, old pebbles out the bottom.
A distinct advantage to be sure, but refueling outages can range from 10 days if you are only refueling the plant (every 18 months) to 25 days minimum if you want to accomplish a number of other things as well. There are activities you can only do when the plant is shutdown, and these activities would be the same for a pebble bed reactor.
Also pay no attention to the fact that each pebble of fuel is of a small enough quantity of fissile material that all the fuel needed to operate a plant for 40 years can be stored on site from when the plant first fires up, to the point it is turned off for good.
Storing all the fuel on site is quite possible with conventional nuke plants as well. Spent fuel typically has to be stored underwater for 10-15 years, and after that, it's often safe enough to dry store onsite in a warehouse. Powerplants designed their spent fuel storage onsite with the promise of a facility like Yucca mountain being open in a reasonable amount of time. The facilities slowness in coming has led to numerous examinations of what we can safely do with spent fuel on site.
Oh, and these things are cheap, and total construction time from ground breaking to flipping the switch is 24 months.
New conventional nuke plants from Westinghouse can be up almost as fast. The lawyers and regulatory burden are typically far more troublesome than any construction process.
Anyway, I agree with you overall, pebble bed reactors look like a 'hot technology' and I'd love to see some of these plants go online.
There was this little bald guy that kicked the entire British empire out of his poor country...and never lifted a gun or sword or any weapon to do it.
This same guy also said: "Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest." - Mahatma Ghandi
Pacifism is great, but it only works against a basically moral enemy. Those without qualms about killing all who oppose them will do so. See Iraq, 6 months ago, Somolia, or any other number of examples. The British couldn't slaughter countless Indians to enforce their rule- one general who did slaughter a number of resisting indians was quickly court marshalled.
I respect that you take responsibility for your childrens upbringing, and what they are exposed to, but I question your reluctance to defend them from bodily harm with the same vigor.
Aren't their bodies as important as their minds to growing up healthy? Why should someone who has no business harming your children be alowed to do so? Maybe you're willing to give up your life to not kill another person, but are you willing to surrender the lives of your wife and children just the same?
Raising your children to be kind and gentle isn't screwing them up by any means, but kindness and gentility won't keep them safe from those who would harm them- there is evil in this world, and keeping it at bay may require violence.
Winged vehicles are unstable during re-entry and need a complex and error-prone automatic flight control system.
There was a slashdot article some months ago, but shuttle code is about as perfect as it gets.
Moreover, auto flight control for a shuttle-like vehicle is not substantially different from commercial aircraft (sure, sometimes it's firing rockets instead of moving aerlorons), and nobody has died from an autopilot error anytime in recent history. (A few have died because they flew in circumstances that the programmers didn't anticipate, and airbus makes the computer the final authority, instead of the pilot.)
Ever notice how the media only tells you another soldier died today, etc, etc?
They don't say there's routine chaos in the streets. They don't say there's no water, no power. They don't say the free market isn't working already over there. They don't tell you that every single Iraqi hates all the American imperialists.
But they would if they could, because many in the american media (fox notwithstanding) want to see Bush and America fail.
Instead, all they have is a few soldiers dying, so they latch onto it with desperation. Incidentally, while I mourn the loss of men and women of honor, a couple hundred dead soldiers is nothing compared to say.... the 10,000 french who died because the french couldn't be bothered to come back from vacation to look after the elderly and sick.
Moreover, we want the Islamofascists attacking our soldiers in Iraq, because our soldiers are well-prepared for it, and kill the imported 'freedom fighters' in great numbers. The bombing of the mosque and the UN recently only shows that the islamofascists are so desperate they're pissing in their own food. They had no greater friend against America than the UN, and now they don't even have that anymore. The more desperate they are, the closer they are to defeat.
Every goat fucking jihaadist who dies fighting our soldiers is one less that will cause their trouble on our shores. So bring em on.
Remember, most of the press hates Bush just like you do. Combined with the old adage 'no news is good news,' then I hope you can imagine why the news you get is trying desperately to make it look like America is failing. The lack of categories they can claim America's failure in should give you an indication that things are going well, for a country only a few months out of a war, with people who would continue it pouring over the border every day.
The Iraqi police have already caught a few of the mosque bombers, and made them sing like canaries. Their intent is to try to keep things chaotic so that more unwelcomed (by the Iraqi people) 'freedom fighters' can pour over the borders.
By the way, did you hear about that Iraqi couple who named their kid George Bush? Or that the imported islamofascists are having increasing trouble attack American Soldiers directly, to the point where they've had to quintiple the 'kill a yankee' bounty? And that these same fucks are having trouble melting into Iraqi crowds, because the Iraqi crowds split around them, to leave them open to American retaliation?
I hate responding to AC's, but then I remembered that Eurotrolls probably eat up any news that can vaugely be taken as anti-american.
A few hundred soldiers over several months is cheap for what we're trying to do there. The $16-40 billion dollars yearly is chump change for the United States.
More euro-troll GWB bashing. Rather old by now, don't you think? You folks better get used to the US kicking ass until at least 2008, because the democratic field for the 2004 election is nothing but a socialist, impotent circle-jerk, a gang that's not fooling nearly enough of the US to land the office.
Look, maybe no one pointed this out to you, but America has been pulling off a strange mix of science and faith for the past 250 years, and we're the most successful nation on the face of the earth because of it.
America's strength is based partly on our judeo-christian heritage, and largely on our constant self-criticism. Whatever the CNN polls say, it's not news, and it's not a problem.
The constant self-criticism more than compensates for fundamentalism, keeping the US the most competitive country on the face of the earth. ANd if you don't believe me, how come so many people are dying (sometimes literally) to become US citizens, and so very few are leaving?
It's funny how many of the euro trolls around here think that the world crying out we're wrong and 'look how stupid america is' will have any effect on our national determination. We've always been our own worst critics, so what a few feckless voices say overseas is irrelevant.
I wouldn't worry about were america is headed right now. We've been kicking ass and taking names for quite some time now, and continue to do the same in Iraq. I would, however, worry about what nihilism, blind anti-americanism, and socialism is doing to europe, though. It's kind of sad watching them swirl around the drain, as they write even more laws to fix their problems, tax wealth creating businesses into oblivion, have diplomats that know nothing of action, and think talk will eventually solve all ills.
agreed. I work at a nuclear power plant, and standing around new fuel is relatively safe, even if it's out in the air.
On the other hand, when we first pull spent fuel out of the reactor for refueling, if it wasn't underwater, and you stood within a few feet of it, it would kill you in seconds.
Why can't these plants just vent un-needed steam pressure if loads suddenly decrease, keeping the generators turning at the reduced load? Is it just impossible to vent 1/3 more heat?
We can, to an extent. If we get an instant demand reduction of 10% of our capacity, the control rods drop in a foot or so, and the change is gracefully accepted. If we get a larger transient- I think up to 40-50% total drop- we can still manage it by dumping more heat into the ocean. For reasons I'm not completely sure of, (I'm still new) we can't gracefully drop any more thermal load into the ocean (possibly because it still has to go through the turbine generator to get to the ocean, risking overspeed destruction if the generator can't use electrical loads for a brake), so if we're completely disconnected, the only choice we have is to vent the steam to the atmosphere through dump valves. These valves are either full open or full closed, I believe, and they don't close back up until the pressure has dropped far below the minimum needed to turn the generator. These vents are mechanical in nature and work off of steam pressure only, so perhaps they can be opened prematurely, but never closed before the safe setpoint. I haven't witnessed this, but from what I understand, dumping billions of joules into the atmosphere via steam is quite a sight- and sound.
Incidentally, gross electrical output is 1207 MW, with a 3411 MW thermal output, so we're slightly more than a third efficient.
How does a power market like France's, at 80% nuclear, deal with changing demand and outages?
Although Nuke plants are typically run at full load, they were designed with the capability to ramp up and down with the daily power usage cycle. In your typical day, loads drop off slowly and add on at the same rate, giving plants of all sizes time to adjust their output. I would suspect that the other 20% of Frances power plants are gas turbine plants that specialize in peaking, to give the nuke plants the ability to ramp up and down, but that's simply a guess.
I wouldn't go for %100 nuclear myself, but nuclear and hydro- now there's a combo. Use hydro for the peaking, and nuke for the baseline, and we could cut fossil fuel consumption, and the resultant pollution dramatically.
If one phase is knocked out- shorted to ground, or whatever, the entire line is disconnected. Phase differentials are bad for the generator, and bad for the motor loads on the recieving end.
In terms of synching grids, I beleive all the subgrids in the national grid keep in the same sync. It would make the most sense to start one plant in a dead grid by using power off another grid, and then reduce the connection to just enough to maintain sync.
If you wanted to adjust sync to a completely seperate, live grid, I'm not sure how you'd do that. This is pure speculation, but perhaps the grid controllers have the capability to remotely adjust all the grid's powerplants syncs at the same time. If they don't, then starting a dead grid plant off of a live grid is the only way to do it, because for any individual plant, the grid power supply is effectively infinite- if you don't catch the freight train just right, you'll be crushed instantly. Perhaps it might be helpful to think of it as electrical inertia, if that makes any sense.
You sure as hell don't want to close breakers out of sync, because the big generators will turn into big motors, and likely rip themselves off their skids, among other numerous and highly destructive effects. (there are sync checks to prevent this)
For maintaining the frequency strictly, all plants have the one speed they turn the generator at, and that puts out 60Hz. This speed can be adjusted by a hertz or so to allow you to catch up to the grid's sync, but once you're locked in, you run at your design speed, because you have no other choice.
I don't know any links for info about day to day operations, sorry.
there are 193 fuel bundles. each of these contain 264 fuel rodlets. Each of these fuel rodlets is 12' long, filled with uranium & ceramic cylinders that are 3/8" in diameter, 5/8" tall, so I think that comes out to about 230 uranium pellets in each rodlet, maybe a dozen less.
So it's roughly a 12' cube (actually more like a squared circle on the horizontal plane, akin to the pixel layout of a lower-case 'o'), with room for control rods, coolant travel, and a few miscelanous other parts. Sub-cooled water at T average = 585 deg F and 2235 psi is passed through the core at 66,000 gallons per minute to extract heat and pass it off to a steam loop that the turbine generator extracts power from.
The exact portion of uranium to ceramic mixture in the individual pellets I'm not sure of, but you should be able to get a good idea- I think it's 5% enriched uranium, 95% uranium, clad in ceramic to make a pellet, then put in a zirciloy tube to form the rodlets. This might be slightly innacurate and I don't feel like looking up the exact info right now.
For the most part, Voltage is dependent on rotational velocity, but remember your generator basics: In order to make electricity you need a conductor, a magnetic field, and motion between the two.
In a generator of any size, it's impractical for a variety of reasons to use permenent magnets to provide this magnetic field, so the magnetic field is set up on the rotor by a DC voltage. Changing this excitation voltage will strengthen or weaken the magnetic field, thus changing the voltage output, even for a given speed.
That's exactly how it works at our plant, only I've only seen it done in the simulator on a diesel generator. I'm not sure how long it takes to adjust the speed of main generator, so I guess a couple minutes.
Funny thing- we had to load one of our diesel generators during a test run a few weeks ago, but lost voltage control. This meant we couldn't tweak the voltage of the DG up a little to take on grid load, and it was just spinning idle. So we used the main generator to drag down the ENTIRE NEW ENGLAND GRID a few volts to load our pissant 6MW diesel generator.
Small generators, like one on a bicycle to power a light don't seem to have that issue.
There's a physical limit to how fast you can spin your legs, so it's pretty much impossible for you to damage the small generator. But if you were pedaling along, and powering a TV that got unplugged, it would suddenly be a whole lot easier to pedal.
Now imagine that transient on a system with no physical limit to it's speed, other than self destruction- and this system is also 17,242,857 times as powerful as your legs. (based on 1207 MW plant output, 70W average continous human output)
When the plant is running, there's several billion joules of energy in the system, waiting to be converted to some other form. 2/3 of that we typically throw away into the ocean, but the other 1/3 we use will overspeed the turbine-generator and blow it apart if the loading undergoes a huge, instant transient, and we don't shut the system down.
A few years ago salem blew apart their turbine from an overspeed test that went wrong. Keep in mind that the generator is on a seperate water loop from the reactor with a heat exchanger in between, so none of this generator destruction would pose a threat to the public, unless their standing within a mile of the sides of the turbine when it finally goes to fast. (That's how far away they found parts of Salem's turbine.)
Please view my/. Profile to check out my other posts on the topic.
In order to generate a specific voltage, the entire steam turbine-generator shaft has to spin at one speed, 1800 RPM. Amperage is a matter of torque.
If we continue to spin the turbines and connected generator with no load, we risk overspeeding them and blowing them apart- so automatic safety systems would often kill the plant in seconds, before operators had a chance to act.
Moreover, we can't go from a 1207 MW load to a 40MW load (what we use in house) instantly- properly ramping down involves changing the chemistry (preferably), or inserting the control rods part way. (We don't like to have these anywhere but all the way in, or all the way out).
Both of those transients take some time (hours) to do in an orderly fashion, and the equipment will be damaged far sooner than that if we stay connected during a large power drop.
In order to give you and idea of how much energy is in the system, and why it needs to be dealt with quickly, consider this: we throw away 2/3 of our thermal energy, turning only about 1/3 of that into electricity. The energy we throw away is enough to raise the temperature of 400 000 gallons per minute of seawater 34 degrees F. (Instead of cooling towers, we use the ocean. Incidentally, cooling towers can be found at plants other than nuke plants.) Please also click on my slashdot profile and read my other posts.
Being a navy nuclear officer/enlisted person gives you experience with reactors very similar to a commercial prssurized water reacter. Most everybody at the plant is an Ex-Navy nuke, or from a Maritime school. So it's a great way to get in. In my class of new NSO's. there's 11 total, 2 of which are ex-navy.
Me and one other kid are actually the oddballs, because we're mechanical engineers from a state university
That's Davis-Besse, and it was Boric Acid Precipitate found under the reactor head. You can go ahead and use google on your own.
Nothing has to be neccessarily retrofitted, just checked over extremely well. Moreover, Davis-Besse knew they had a boric acid leak and corrosion for quite some time, they just chose to ignore the scope of it, and not seek the cause of their chemistry abnormalities. All their management has now been cleaned out, I believe, top to bottom.
But yeah, that was pretty significant. If it had gone unnoticed for a few months longer, it could have been three mile island #2- but I'd like to point out that there was NO SIGNIFICANT RADIATION RELEASE from TMI, and their wouldn't have been from this, either.
All i have is a BS in Mechanical Engineering and some experience in workplace safety and using and following procedures. And a clean bill of health, criminal record, and credit record.
Of course, the soft skills department shouldn't be neglected- work on your interviewing and resume writing skills, and remember that first impressions count the most when you walk in the door. Interview at a number of places you're only milded interested in. My first interview I fucked up in every way possible, but the Nuke plant was my fourth interview or so, so I had it down by then.
if things run nationwide like they do at my plant, seabrookstation (http://www.seabrookstation), then the demand specifically for nuclear engineers right out of college is somewhat small- we only have a handfull at our plant, and none were hired this past year.
If you want to get anywhere in a nukeplant, start in operations. As an Nuclear Systems operator (NSO), I'm gonna be running around the plant, taking equipment in and out of service, opening and closing valves, and whatever the licensed operators in the control room tell me to do. It's basically a well-paid (I'm about 12% over the starting pay for Mechanical Engineers in New England) blue collar job, open to only to those with engineering degrees or Navy experience.
However, the guys in the control room- all were NSO's. The plant manager- started as an NSO. And a good portion of the plant engineers started as an NSO.
So your easiest entry into the nuclear field is going to involve getting dirty for the first few years. Once you know the plant (they're all similar), if you have the right academic credentials, you'll be in a great position to post for new plant engineering positions as they open, at your plant or others. Just don't let your engineering knowledge rust those years you're spinning valves.
Do I like it? So far, yes, but I've only been learning about the plant. The systems are incredibly complex, and thus insanely cool to engineering-minded folks.
The work itself, as an NSO, often involves long periods of boredom, interspersed with the occasional work and the rare crisis (by crisis, I mean something has to be fixed FAST or the plant has to be shut down by NRC rules. Almost never does this mean that a worker, or the public, is in any iminent danger. A crisis is usually a buearocratic affair.) Mostly, as an NSO, you monitor. But it opens up every other job in the plant to you, because you know the plant inside and out.
Of course, if you can go right to an engineering position, good for you, if that's what you want. Try calling a few area plants and asking about internships.
Maybe my wording was unclear- Nuke plants do produce about 20% of the power we consume.
There are only 104 nuclear powerplants in the US, you're right on that.
However, These plants have 1-3 reactors at each site, each producing roughly a gigawatt of electricity- enough for a million homes.
So you've got at a minimum, 150 gigawatts output of just these 100 powerplants. Take your electricity bill, and figure out your average hourly kilowatt usage. Now divide 150 GW by your average consumption.
Do you still think I'm wrong? Or does it kinda look like nuclear power could run every home in the United states by itself? (Of course, if we wanted to run businesses and industry, we'd have to bring all the other plants back on.)
Seabrook is where I work, and How stuff works says 15% for the US, the US department of energy says 18.6%, both of which are close enough to the 20% I stated.
I thought the "grid" was, basically, composed of consumers and producers of energy. I know that there is a balancing act between supply, demand, and the requirement to balance the loads within line segments, but it was my understanding that as long as there were consumers for your energy then you could generate it.
That's an oversimplification, I know. But I don't understand this case: A major power producer goes offline, but the consumers don't. Why can't the remaining producers take up at least some of the slack?
www.howstuffworks.com might have some good information, but I don't have any direct links.
The grid is composed of three parts: producers, transmission, and consumers.
Now when a major plant goes offline, typically other plants do take up the slack, so you've got the right idea. For example, in October, Seabrook station will go offline for refueling, and no one will notice, because we're paying other plants to generate the electricity we committed to. The excess peaking capacity of the grid goes down, so there's a smaller margin for peaks, but brownouts are largely avoided.
Now in comes the transmitters: It's often referred to as 'The national electric grid' but that's not quite correct. The system is capable of transmitting power from Maine to California, and Florida to Toronto, but there's a lot of sub-grids with sometimes minor connections between them, and these are typically open- there might be a small connection for keeping sync, so they can close on demand.
Each inter-grid connection can only carry so much current- the lines would heat up and start to sag, substations would catch on fire, that sort of thing. This can't really be tolerated, so when a connection's capacity is overloaded, the breakers pop open and the 'donor' grid just gives a big 'fuck off' to the recieving grid.
So when this happens, it starts to ask even more of the other grids it's connected to, increasing the chance that it will cause an overcurrent trip on these other lines.
These connections can also be manually opened and closed by the grid controllers- in NH, the control room is in manchester, and I think it's run by a company called ISO. An overcurrent trip may require a lineman to visit the substation in question, i'm not sure.
Now, every plant except nuke plants runs lower than it's actual capacity to keep some peak demand reserve, so in general, they can pick up the slack when one goes down. Each powerplant does have it's limit, though. If demand on a particular plant exceeds it's capacity, the voltage will drop, and the plant will likely trip on undervoltage, or a grid connection might trip, or the plant operators might shut the plant down to preserve the equipment. (Most things in my powerplant like to run at one-steady state speed. Since voltage is proportional to speed, lower voltage means the main generator and turbine slow down. I won't go into the details, but suffice it to say, it's no fun) Shutting down one plant will of course increase demand on other plants. So I'm sure you can see by now that once a cascade starts, things can really start to go to shit.
This is ideally avoided by having ridiculously over-rated transmission lines, and grid excess generation capacity well above the output of any one or two or three plants. However, I don't think we've really beefed up our transmission lines since the 70's or 80's, and new powerplants are often stalled or killed by NIMBY's and groups like greenpeace who haven't the slightest clue how a nuke plant works, how it's different from a bomb, and how many robust safety systems there are between the radiation and the public.
We've been setting ourselves up for problems for sometime now. It's time to build new power plants, and beef up transmission lines, cause demand sure as hell won't recede.
Corrections to my statements are welcomed from people with more than my meager two months in the power industry.
The power outage shut down nuclear power plants??? What the hell are those things for?
Short answer: If they have no place to put all the power they generate, they have to shut down.
My plant generates 1207 Mega-watts (which rounds to 1.21 gigawatts... hehhehe), and we only use 40 MW for in house loads- about three percent of our total output. We cannot ramp output from 1207 MW to 40 MW instantly, if we can at all (I'm new, so I still have much to learn. The only option, then , is to unplug everything and blow as much of the energy into the ultimate heat sink (ocean) quickly.
Once the plant goes offline, it takes about a day to start back up again- and we can't start without being connected to the grid, because our diesels only put out 12 MW at 4160 Volts. This is enough to shut down the plant safely, but far short of the 40MW (most of it at 13600 Volts) needed to run the seven big motors that are needed for circulating the reactor coolant and dumping waste heat into the ocean. Even if we could run off of only one waste heat and one reactor coolant motor, we'd still have to hook up the plant wiring in a creative way to do that, and it would take a long time to convince the NRC that was a good idea.
And Newington and Schiller station, and many power plants in Massachusetts, Maine, and New Hampshire. Seabrook is a big plant, but can hardly power New England by itself- though it does provide 6%.
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A nuclear power plant design for 1000Mw, 500Mw, etc... has been approved for build by the appropriate agencies...The plant can be built immediately or as soon as possible and would only require inspections and testing, and would not require a design submission.
You mean something like Westinghouses AP600/AP1000 nuclear reactors?
The NRC has approved the AP600, they love it, and the AP1000 is simply a scaled up version. From what I hear at my workplace, the NRC now has a system in place to get plants up and running in 5 years or so, from a licensing standpoint. Most plants in the US are of Westinghouse design, so their work could be seen as a de-facto standard. Combined with potential federal loan guarantees for another 8,400 MW of nuke plants, and you may yet see nuclear construction in the next few years.
In terms of legal hurdles, the easiest way to expand the US nuclear fleet is to add reactors at existing sites. The local population is already quite used to living in the shadow of these plants, and will probably just see it as more jobs.
heheh kinda funny.. but it was said that DU munitions are only dangerous when it's coming at you at 3,200 FPS, and then any real or imagined long term health problems are largely irrellevent.
Never mind that also in said reactor, you don't have to shut it down for months to refuel it - new pebbles in the top, old pebbles out the bottom.
A distinct advantage to be sure, but refueling outages can range from 10 days if you are only refueling the plant (every 18 months) to 25 days minimum if you want to accomplish a number of other things as well. There are activities you can only do when the plant is shutdown, and these activities would be the same for a pebble bed reactor.
Also pay no attention to the fact that each pebble of fuel is of a small enough quantity of fissile material that all the fuel needed to operate a plant for 40 years can be stored on site from when the plant first fires up, to the point it is turned off for good.
Storing all the fuel on site is quite possible with conventional nuke plants as well. Spent fuel typically has to be stored underwater for 10-15 years, and after that, it's often safe enough to dry store onsite in a warehouse. Powerplants designed their spent fuel storage onsite with the promise of a facility like Yucca mountain being open in a reasonable amount of time. The facilities slowness in coming has led to numerous examinations of what we can safely do with spent fuel on site.
Oh, and these things are cheap, and total construction time from ground breaking to flipping the switch is 24 months.
New conventional nuke plants from Westinghouse can be up almost as fast. The lawyers and regulatory burden are typically far more troublesome than any construction process.
Anyway, I agree with you overall, pebble bed reactors look like a 'hot technology' and I'd love to see some of these plants go online.
Guns do one thing: put holes in whatever they are pointed at when the trigger is pulled.
It is always just to put holes in targets.
It is often just to put holes in animals, which will lead to their death. It's certainly no more or less cruel than what beasts do to one another.
It is occasionally just to put a hole in your fellow human, when said human seeks to do harm to you and your kin, and has no just reason to do so.
There was this little bald guy that kicked the entire British empire out of his poor country...and never lifted a gun or sword or any weapon to do it.
This same guy also said:
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest." - Mahatma Ghandi
Pacifism is great, but it only works against a basically moral enemy. Those without qualms about killing all who oppose them will do so. See Iraq, 6 months ago, Somolia, or any other number of examples. The British couldn't slaughter countless Indians to enforce their rule- one general who did slaughter a number of resisting indians was quickly court marshalled.
I respect that you take responsibility for your childrens upbringing, and what they are exposed to, but I question your reluctance to defend them from bodily harm with the same vigor.
Aren't their bodies as important as their minds to growing up healthy? Why should someone who has no business harming your children be alowed to do so? Maybe you're willing to give up your life to not kill another person, but are you willing to surrender the lives of your wife and children just the same?
Raising your children to be kind and gentle isn't screwing them up by any means, but kindness and gentility won't keep them safe from those who would harm them- there is evil in this world, and keeping it at bay may require violence.
Well, just my two cents.
Winged vehicles are unstable during re-entry and need a complex and error-prone automatic flight control system.
There was a slashdot article some months ago, but shuttle code is about as perfect as it gets.
Moreover, auto flight control for a shuttle-like vehicle is not substantially different from commercial aircraft (sure, sometimes it's firing rockets instead of moving aerlorons), and nobody has died from an autopilot error anytime in recent history. (A few have died because they flew in circumstances that the programmers didn't anticipate, and airbus makes the computer the final authority, instead of the pilot.)
Ever notice how the media only tells you another soldier died today, etc, etc?
They don't say there's routine chaos in the streets. They don't say there's no water, no power. They don't say the free market isn't working already over there. They don't tell you that every single Iraqi hates all the American imperialists.
But they would if they could, because many in the american media (fox notwithstanding) want to see Bush and America fail.
Instead, all they have is a few soldiers dying, so they latch onto it with desperation. Incidentally, while I mourn the loss of men and women of honor, a couple hundred dead soldiers is nothing compared to say.... the 10,000 french who died because the french couldn't be bothered to come back from vacation to look after the elderly and sick.
Moreover, we want the Islamofascists attacking our soldiers in Iraq, because our soldiers are well-prepared for it, and kill the imported 'freedom fighters' in great numbers. The bombing of the mosque and the UN recently only shows that the islamofascists are so desperate they're pissing in their own food. They had no greater friend against America than the UN, and now they don't even have that anymore. The more desperate they are, the closer they are to defeat.
Every goat fucking jihaadist who dies fighting our soldiers is one less that will cause their trouble on our shores. So bring em on.
Remember, most of the press hates Bush just like you do. Combined with the old adage 'no news is good news,' then I hope you can imagine why the news you get is trying desperately to make it look like America is failing. The lack of categories they can claim America's failure in should give you an indication that things are going well, for a country only a few months out of a war, with people who would continue it pouring over the border every day.
The Iraqi police have already caught a few of the mosque bombers, and made them sing like canaries. Their intent is to try to keep things chaotic so that more unwelcomed (by the Iraqi people) 'freedom fighters' can pour over the borders.
By the way, did you hear about that Iraqi couple who named their kid George Bush? Or that the imported islamofascists are having increasing trouble attack American Soldiers directly, to the point where they've had to quintiple the 'kill a yankee' bounty? And that these same fucks are having trouble melting into Iraqi crowds, because the Iraqi crowds split around them, to leave them open to American retaliation?
I hate responding to AC's, but then I remembered that Eurotrolls probably eat up any news that can vaugely be taken as anti-american.
A few hundred soldiers over several months is cheap for what we're trying to do there. The $16-40 billion dollars yearly is chump change for the United States.
More euro-troll GWB bashing. Rather old by now, don't you think? You folks better get used to the US kicking ass until at least 2008, because the democratic field for the 2004 election is nothing but a socialist, impotent circle-jerk, a gang that's not fooling nearly enough of the US to land the office.
Look, maybe no one pointed this out to you, but America has been pulling off a strange mix of science and faith for the past 250 years, and we're the most successful nation on the face of the earth because of it.
America's strength is based partly on our judeo-christian heritage, and largely on our constant self-criticism. Whatever the CNN polls say, it's not news, and it's not a problem.
The constant self-criticism more than compensates for fundamentalism, keeping the US the most competitive country on the face of the earth. ANd if you don't believe me, how come so many people are dying (sometimes literally) to become US citizens, and so very few are leaving?
It's funny how many of the euro trolls around here think that the world crying out we're wrong and 'look how stupid america is' will have any effect on our national determination. We've always been our own worst critics, so what a few feckless voices say overseas is irrelevant.
I wouldn't worry about were america is headed right now. We've been kicking ass and taking names for quite some time now, and continue to do the same in Iraq.
I would, however, worry about what nihilism, blind anti-americanism, and socialism is doing to europe, though. It's kind of sad watching them swirl around the drain, as they write even more laws to fix their problems, tax wealth creating businesses into oblivion, have diplomats that know nothing of action, and think talk will eventually solve all ills.
It's the world's tiniest violin, playing a sad, sad funeral dirge for SCO.
agreed. I work at a nuclear power plant, and standing around new fuel is relatively safe, even if it's out in the air.
On the other hand, when we first pull spent fuel out of the reactor for refueling, if it wasn't underwater, and you stood within a few feet of it, it would kill you in seconds.
Why can't these plants just vent un-needed steam pressure if loads suddenly decrease, keeping the generators turning at the reduced load? Is it just impossible to vent 1/3 more heat?
We can, to an extent. If we get an instant demand reduction of 10% of our capacity, the control rods drop in a foot or so, and the change is gracefully accepted. If we get a larger transient- I think up to 40-50% total drop- we can still manage it by dumping more heat into the ocean.
For reasons I'm not completely sure of, (I'm still new) we can't gracefully drop any more thermal load into the ocean (possibly because it still has to go through the turbine generator to get to the ocean, risking overspeed destruction if the generator can't use electrical loads for a brake), so if we're completely disconnected, the only choice we have is to vent the steam to the atmosphere through dump valves. These valves are either full open or full closed, I believe, and they don't close back up until the pressure has dropped far below the minimum needed to turn the generator. These vents are mechanical in nature and work off of steam pressure only, so perhaps they can be opened prematurely, but never closed before the safe setpoint. I haven't witnessed this, but from what I understand, dumping billions of joules into the atmosphere via steam is quite a sight- and sound.
Incidentally, gross electrical output is 1207 MW, with a 3411 MW thermal output, so we're slightly more than a third efficient.
How does a power market like France's, at 80% nuclear, deal with changing demand and outages?
Although Nuke plants are typically run at full load, they were designed with the capability to ramp up and down with the daily power usage cycle. In your typical day, loads drop off slowly and add on at the same rate, giving plants of all sizes time to adjust their output. I would suspect that the other 20% of Frances power plants are gas turbine plants that specialize in peaking, to give the nuke plants the ability to ramp up and down, but that's simply a guess.
I wouldn't go for %100 nuclear myself, but nuclear and hydro- now there's a combo. Use hydro for the peaking, and nuke for the baseline, and we could cut fossil fuel consumption, and the resultant pollution dramatically.
If one phase is knocked out- shorted to ground, or whatever, the entire line is disconnected. Phase differentials are bad for the generator, and bad for the motor loads on the recieving end.
In terms of synching grids, I beleive all the subgrids in the national grid keep in the same sync. It would make the most sense to start one plant in a dead grid by using power off another grid, and then reduce the connection to just enough to maintain sync.
If you wanted to adjust sync to a completely seperate, live grid, I'm not sure how you'd do that. This is pure speculation, but perhaps the grid controllers have the capability to remotely adjust all the grid's powerplants syncs at the same time. If they don't, then starting a dead grid plant off of a live grid is the only way to do it, because for any individual plant, the grid power supply is effectively infinite- if you don't catch the freight train just right, you'll be crushed instantly. Perhaps it might be helpful to think of it as electrical inertia, if that makes any sense.
You sure as hell don't want to close breakers out of sync, because the big generators will turn into big motors, and likely rip themselves off their skids, among other numerous and highly destructive effects. (there are sync checks to prevent this)
For maintaining the frequency strictly, all plants have the one speed they turn the generator at, and that puts out 60Hz. This speed can be adjusted by a hertz or so to allow you to catch up to the grid's sync, but once you're locked in, you run at your design speed, because you have no other choice.
I don't know any links for info about day to day operations, sorry.
And you're welcome:).
there are 193 fuel bundles.
each of these contain 264 fuel rodlets. Each of these fuel rodlets is 12' long, filled with uranium & ceramic cylinders that are 3/8" in diameter, 5/8" tall, so I think that comes out to about 230 uranium pellets in each rodlet, maybe a dozen less.
So it's roughly a 12' cube (actually more like a squared circle on the horizontal plane, akin to the pixel layout of a lower-case 'o'), with room for control rods, coolant travel, and a few miscelanous other parts. Sub-cooled water at T average = 585 deg F and 2235 psi is passed through the core at 66,000 gallons per minute to extract heat and pass it off to a steam loop that the turbine generator extracts power from.
The exact portion of uranium to ceramic mixture in the individual pellets I'm not sure of, but you should be able to get a good idea- I think it's 5% enriched uranium, 95% uranium, clad in ceramic to make a pellet, then put in a zirciloy tube to form the rodlets. This might be slightly innacurate and I don't feel like looking up the exact info right now.
Hope that helps
For the most part, Voltage is dependent on rotational velocity, but remember your generator basics:
In order to make electricity you need a conductor, a magnetic field, and motion between the two.
In a generator of any size, it's impractical for a variety of reasons to use permenent magnets to provide this magnetic field, so the magnetic field is set up on the rotor by a DC voltage. Changing this excitation voltage will strengthen or weaken the magnetic field, thus changing the voltage output, even for a given speed.
Amperage is proportional to applied torque.
That's exactly how it works at our plant, only I've only seen it done in the simulator on a diesel generator. I'm not sure how long it takes to adjust the speed of main generator, so I guess a couple minutes.
Funny thing- we had to load one of our diesel generators during a test run a few weeks ago, but lost voltage control. This meant we couldn't tweak the voltage of the DG up a little to take on grid load, and it was just spinning idle. So we used the main generator to drag down the ENTIRE NEW ENGLAND GRID a few volts to load our pissant 6MW diesel generator.
Now that's power. heheheh
Small generators, like one on a bicycle to power a light don't seem to have that issue.
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There's a physical limit to how fast you can spin your legs, so it's pretty much impossible for you to damage the small generator. But if you were pedaling along, and powering a TV that got unplugged, it would suddenly be a whole lot easier to pedal.
Now imagine that transient on a system with no physical limit to it's speed, other than self destruction- and this system is also 17,242,857 times as powerful as your legs. (based on 1207 MW plant output, 70W average continous human output)
When the plant is running, there's several billion joules of energy in the system, waiting to be converted to some other form. 2/3 of that we typically throw away into the ocean, but the other 1/3 we use will overspeed the turbine-generator and blow it apart if the loading undergoes a huge, instant transient, and we don't shut the system down.
A few years ago salem blew apart their turbine from an overspeed test that went wrong. Keep in mind that the generator is on a seperate water loop from the reactor with a heat exchanger in between, so none of this generator destruction would pose a threat to the public, unless their standing within a mile of the sides of the turbine when it finally goes to fast. (That's how far away they found parts of Salem's turbine.)
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In order to generate a specific voltage, the entire steam turbine-generator shaft has to spin at one speed, 1800 RPM. Amperage is a matter of torque.
If we continue to spin the turbines and connected generator with no load, we risk overspeeding them and blowing them apart- so automatic safety systems would often kill the plant in seconds, before operators had a chance to act.
Moreover, we can't go from a 1207 MW load to a 40MW load (what we use in house) instantly- properly ramping down involves changing the chemistry (preferably), or inserting the control rods part way. (We don't like to have these anywhere but all the way in, or all the way out).
Both of those transients take some time (hours) to do in an orderly fashion, and the equipment will be damaged far sooner than that if we stay connected during a large power drop.
In order to give you and idea of how much energy is in the system, and why it needs to be dealt with quickly, consider this: we throw away 2/3 of our thermal energy, turning only about 1/3 of that into electricity. The energy we throw away is enough to raise the temperature of 400 000 gallons per minute of seawater 34 degrees F. (Instead of cooling towers, we use the ocean. Incidentally, cooling towers can be found at plants other than nuke plants.)
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Being a navy nuclear officer/enlisted person gives you experience with reactors very similar to a commercial prssurized water reacter. Most everybody at the plant is an Ex-Navy nuke, or from a Maritime school. So it's a great way to get in. In my class of new NSO's. there's 11 total, 2 of which are ex-navy.
Me and one other kid are actually the oddballs, because we're mechanical engineers from a state university
That's Davis-Besse, and it was Boric Acid Precipitate found under the reactor head. You can go ahead and use google on your own.
Nothing has to be neccessarily retrofitted, just checked over extremely well. Moreover, Davis-Besse knew they had a boric acid leak and corrosion for quite some time, they just chose to ignore the scope of it, and not seek the cause of their chemistry abnormalities. All their management has now been cleaned out, I believe, top to bottom.
But yeah, that was pretty significant. If it had gone unnoticed for a few months longer, it could have been three mile island #2- but I'd like to point out that there was NO SIGNIFICANT RADIATION RELEASE from TMI, and their wouldn't have been from this, either.
Fuckin Davis-Besse assholes....
All i have is a BS in Mechanical Engineering and some experience in workplace safety and using and following procedures. And a clean bill of health, criminal record, and credit record.
Of course, the soft skills department shouldn't be neglected- work on your interviewing and resume writing skills, and remember that first impressions count the most when you walk in the door. Interview at a number of places you're only milded interested in. My first interview I fucked up in every way possible, but the Nuke plant was my fourth interview or so, so I had it down by then.
if things run nationwide like they do at my plant, seabrookstation (http://www.seabrookstation), then the demand specifically for nuclear engineers right out of college is somewhat small- we only have a handfull at our plant, and none were hired this past year.
If you want to get anywhere in a nukeplant, start in operations. As an Nuclear Systems operator (NSO), I'm gonna be running around the plant, taking equipment in and out of service, opening and closing valves, and whatever the licensed operators in the control room tell me to do.
It's basically a well-paid (I'm about 12% over the starting pay for Mechanical Engineers in New England) blue collar job, open to only to those with engineering degrees or Navy experience.
However, the guys in the control room- all were NSO's. The plant manager- started as an NSO. And a good portion of the plant engineers started as an NSO.
So your easiest entry into the nuclear field is going to involve getting dirty for the first few years. Once you know the plant (they're all similar), if you have the right academic credentials, you'll be in a great position to post for new plant engineering positions as they open, at your plant or others. Just don't let your engineering knowledge rust those years you're spinning valves.
Do I like it? So far, yes, but I've only been learning about the plant. The systems are incredibly complex, and thus insanely cool to engineering-minded folks.
The work itself, as an NSO, often involves long periods of boredom, interspersed with the occasional work and the rare crisis (by crisis, I mean something has to be fixed FAST or the plant has to be shut down by NRC rules. Almost never does this mean that a worker, or the public, is in any iminent danger. A crisis is usually a buearocratic affair.) Mostly, as an NSO, you monitor. But it opens up every other job in the plant to you, because you know the plant inside and out.
Of course, if you can go right to an engineering position, good for you, if that's what you want. Try calling a few area plants and asking about internships.
Maybe my wording was unclear- Nuke plants do produce about 20% of the power we consume.
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There are only 104 nuclear powerplants in the US, you're right on that.
However, These plants have 1-3 reactors at each site, each producing roughly a gigawatt of electricity- enough for a million homes.
So you've got at a minimum, 150 gigawatts output of just these 100 powerplants. Take your electricity bill, and figure out your average hourly kilowatt usage. Now divide 150 GW by your average consumption.
Do you still think I'm wrong? Or does it kinda look like nuclear power could run every home in the United states by itself? (Of course, if we wanted to run businesses and industry, we'd have to bring all the other plants back on.)
check
http://www.nei.org/ http://science.howstuffworks.com/nuclear-power.ht
http://www.seabrookstation.com
Seabrook is where I work, and How stuff works says 15% for the US, the US department of energy says 18.6%, both of which are close enough to the 20% I stated.
I thought the "grid" was, basically, composed of consumers and producers of energy. I know that there is a balancing act between supply, demand, and the requirement to balance the loads within line segments, but it was my understanding that as long as there were consumers for your energy then you could generate it.
That's an oversimplification, I know. But I don't understand this case: A major power producer goes offline, but the consumers don't. Why can't the remaining producers take up at least some of the slack?
www.howstuffworks.com might have some good information, but I don't have any direct links.
The grid is composed of three parts: producers, transmission, and consumers.
Now when a major plant goes offline, typically other plants do take up the slack, so you've got the right idea. For example, in October, Seabrook station will go offline for refueling, and no one will notice, because we're paying other plants to generate the electricity we committed to. The excess peaking capacity of the grid goes down, so there's a smaller margin for peaks, but brownouts are largely avoided.
Now in comes the transmitters: It's often referred to as 'The national electric grid' but that's not quite correct. The system is capable of transmitting power from Maine to California, and Florida to Toronto, but there's a lot of sub-grids with sometimes minor connections between them, and these are typically open- there might be a small connection for keeping sync, so they can close on demand.
Each inter-grid connection can only carry so much current- the lines would heat up and start to sag, substations would catch on fire, that sort of thing. This can't really be tolerated, so when a connection's capacity is overloaded, the breakers pop open and the 'donor' grid just gives a big 'fuck off' to the recieving grid.
So when this happens, it starts to ask even more of the other grids it's connected to, increasing the chance that it will cause an overcurrent trip on these other lines.
These connections can also be manually opened and closed by the grid controllers- in NH, the control room is in manchester, and I think it's run by a company called ISO. An overcurrent trip may require a lineman to visit the substation in question, i'm not sure.
Now, every plant except nuke plants runs lower than it's actual capacity to keep some peak demand reserve, so in general, they can pick up the slack when one goes down. Each powerplant does have it's limit, though. If demand on a particular plant exceeds it's capacity, the voltage will drop, and the plant will likely trip on undervoltage, or a grid connection might trip, or the plant operators might shut the plant down to preserve the equipment. (Most things in my powerplant like to run at one-steady state speed. Since voltage is proportional to speed, lower voltage means the main generator and turbine slow down. I won't go into the details, but suffice it to say, it's no fun)
Shutting down one plant will of course increase demand on other plants. So I'm sure you can see by now that once a cascade starts, things can really start to go to shit.
This is ideally avoided by having ridiculously over-rated transmission lines, and grid excess generation capacity well above the output of any one or two or three plants. However, I don't think we've really beefed up our transmission lines since the 70's or 80's, and new powerplants are often stalled or killed by NIMBY's and groups like greenpeace who haven't the slightest clue how a nuke plant works, how it's different from a bomb, and how many robust safety systems there are between the radiation and the public.
We've been setting ourselves up for problems for sometime now. It's time to build new power plants, and beef up transmission lines, cause demand sure as hell won't recede.
Corrections to my statements are welcomed from people with more than my meager two months in the power industry.
**Nuke plants typically run at full power
The power outage shut down nuclear power plants??? What the hell are those things for?
Short answer: If they have no place to put all the power they generate, they have to shut down.
My plant generates 1207 Mega-watts (which rounds to 1.21 gigawatts... hehhehe), and we only use 40 MW for in house loads- about three percent of our total output. We cannot ramp output from 1207 MW to 40 MW instantly, if we can at all (I'm new, so I still have much to learn. The only option, then , is to unplug everything and blow as much of the energy into the ultimate heat sink (ocean) quickly.
Once the plant goes offline, it takes about a day to start back up again- and we can't start without being connected to the grid, because our diesels only put out 12 MW at 4160 Volts. This is enough to shut down the plant safely, but far short of the 40MW (most of it at 13600 Volts) needed to run the seven big motors that are needed for circulating the reactor coolant and dumping waste heat into the ocean. Even if we could run off of only one waste heat and one reactor coolant motor, we'd still have to hook up the plant wiring in a creative way to do that, and it would take a long time to convince the NRC that was a good idea.
And Newington and Schiller station, and many power plants in Massachusetts, Maine, and New Hampshire. Seabrook is a big plant, but can hardly power New England by itself- though it does provide 6%.
Seabrook, I assure you, is at full power. I work there.