First New US Nuclear Reactor In Two Decades Gets Permission To Begin Fueling (ieee.org) 167
An anonymous reader writes: The Tennessee Valley Authority's Watts Bar nuclear power plant began construction in 1973. The plant's first reactor was completed in 1996, and it began operation. Work on the second reactor paused in 1988, and only resumed in 2007. That reactor is now complete — the first newly-operational Generation II reactor since the 1990s. The new reactor has been granted an operational license, and it will soon begin fueling. While the Gen II reactors aren't unsafe, they're much less safe than the Gen III AP1000s. "Compared to a Westinghouse Gen II PWR, the AP1000 contains 50 percent fewer safety-related valves, 35 percent fewer pumps, 80 percent less safety-related piping, 85 percent less control cabling, and 45 percent less seismic building volume. ... If an accident happens, the AP1000 will shut itself down without needing any human intervention (or even electrical power) within the first 72 hours."
Stupid (Score:5, Insightful)
If the government could make its mind up and stop wasting time, the US could rapidly diminish and even eliminate its reliance on fossil fuels without even having to suffer through energy shortages. Allow breeder reactors on top and you'd also eliminate the whole nuclear waste scare while being that much more efficient and cost-effective.
Re: Stupid (Score:3)
Yeah but won't someone thingof the oil company execs and investors? This nuclear shit is going to fuck them over.
Those lamborghinis arent going to gold plate themselves, you know? Now think about the poor metalurgists and day laborers whom will be out of work. Oh what's that? You didn't think about them?
I didn't think so.
Re: Stupid (Score:4, Insightful)
"Yeah but won't someone thingof the oil company execs and investors? This nuclear shit is going to fuck them over."
Funny how such a stupid post get a 3.
Less than 3% of the electricity in the US comes from oil.
Coal, and natural gas are the two big fossil fuels used for electrical power in the US. While you do have some cross over between oil and natural gas it is not 100% as far as companies.
BTW the same thing holds true for anyone that says that solar and wind will help cut the US's dependence on foreign oil.
They are lying.
Re: Stupid (Score:2)
No one wants a beta reactor (Score:3, Interesting)
I think that no new nuclear reactors have been built in the United States, because no one wants a beta gen III+ nuclear reactor. In the West, there were 3 different nuclear reactors, Areva's EPR reactor, Westinghouse's AP1000 reactor, and GE's ESBWR reactor. GE decided to exit the nuclear reactor business. Several AP1000s, and EPRs have been under construction in Europe and China since the late 2000s. The EPR reactor in Finland is considered a screw up, and is getting major design changes. China hasn't been
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No-one wants a beta reactor, they want something that will predictably generate electricity at a reasonable cost. That's why virtually every reactor being built today, including the four new-build AP-1000s at Vogtle and Summer as well as the dozens of reactors under construction in China and elsewhere are an evolutionary development of the PWR/BWR concept. The design effort has been concentrated in ever greater cost efficiencies and safety enhancements in larger and more efficient designs generating more el
The LFTR Fairy (Score:2)
Actually, no China isn't putting a crapton of resources into LFTR. It's actually putting about a hundred billion bucks into building a lot of PWRs with more to come in the next ten years or so if they continue the way they're going. Chinese researchers are looking at molten-salt reactor technologies but no significant money has been spent, same with fast-spectrum reactors like the Russian BN-series designs which at least exist in the real world. They're not building any molten-salt reactors, they have no pl
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[sic]This is what the stupid scaremongering of the media, some politicians and many environmentalists ends up causing: instead of building Gen III or even Gen IV plants, we're finishing ancient Gen II plants because that's all that's been approved, decades ago.
The 2005 Energy act prevents entities like that and local governments from interfering with the placement and approval of Nuclear facilities, including Reactors. Compliance for building a nuclear reactor was established by the NRC's predecessor, the Atomic Energy Commission so it has very little to do with the groups you mentioned.
They are quite literally the cause for nuclear energy's relative safety concerns.
I'd suggest that it is more the operator of the facilities not complying with the manufacturers recommended operating conditions for the reactors. Windscale, TMI, Chernobyl and Fu
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It just confirmed what has been obvious for decades. Part of the long chain of fuckups at Fukushima was having stuff "temporarily" on-site that should have had something better than the ridiculous adhoc storage that was used implemented a couple of decades ago.
Also reprocessing is a method to avoid a shortage of fuel, it's not a waste manag
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Precisely. I'm not against the idea of developing nuclear power but any rational person looking at the facts will uncover that it has a lot of problems that need to be fixed. It has the potential to solve problems, if it is done right however all to
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So basically capitalism fucks things like nuclear power up with is emphasis on short term profits over everything else.
There is a reason it took governments to put us into space. I think that government has a role in innovation doing risky stuff that has to be done right. You wouldn't expect a profit from running a Nuclear submarine because it has a very specific role.
From what I've learned about Admiral Rickover [wikipedia.org] he was the kind of guy that had little tolerance for stupid people which probably why the naval reactor program hasn't had any accidents.
There is absolutely no reason why such a culture couldn't exist for nucl
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It is not a scare though, it is a valid concern as Fukushima has really shown us that storing the spent fuel at reactor sites is a really bad idea when things go wrong.
Was that any bit of the issue in Fukushima? I wasn't aware with the spent pools causing issues, only the failure to pump water into the reactors so that they could cool properly while shutting down, which was mostly caused by the 50hz/60hz issues of Japan's electric grid, with the generators being washed away in the flood (or just damaged), and an absolute destruction of most roads feeding the plant preventing new generators from being brought on site.
What problems were caused by the spent fuel pools? Tho
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Well, if Mr.Kaos reads the thousand page regulations that way, I guess it's so.
I am a voracious reader, so have a read of the law yourself and share what you find if you disagree. It's not fun and it's only 500 odd pages, which isn't huge, mostly boring with some interesting moments.
The oil and coal industry lobby politicians to safeguard their interests because business is brutal, you're hopelessly naive if you don't think that the coal industry celebrates a market win over nuclear via a legislative construct. If you are uncomfortable about the legislative hold that the oil and coa
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If the government could make its mind up and stop wasting time, the US could rapidly diminish and even eliminate its reliance on fossil fuels
I'm not sure about that, unless by "make its mind up" you mean the government makes a big intervention into the economics, rather than merely streamlining the regulatory process. The crash in natural-gas prices has really killed the fundamental economics of a lot of nuclear plants that were in the works. With the huge up-front capital costs of nuclear plant constructio
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The capital costs are high because we choose to let them be high. The materials and labor of building a nuclear plant are a small fraction of the cost of building one. Most of the money actually spent is spent on delays. No design changes are allowed, no matter how trivial, without regulatory approval, which takes time. But even that pales in comparison to the legal fights. Every challenge, no matter how frivolous, gets their day in court, usually their year in court, and like whack-a-mole, as soon as
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It was that way (Score:4, Informative)
That was the regulatory regime beforehand, and it resulted in the most colossal waste of money ever: Shoreham [wikipedia.org]
The combined (construction & operating) license regulatory regime [nrc.gov] is intended specifically to prevent such wasteful endevours, The design, construction, and operation of the facility is approved largely upfront to ensure the plant can actually be operated when it's built.
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COSTS OF NUCLEAR POWER PLANTS - WHAT WENT WRONG? [pitt.edu]
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Except nobody would want to do it that way. Its like remodeling a residence ( or building one ) you get inspections as you go. You want the city's you want the assay guy to confirm the foundation you dug isn't to close to the property lines before you pour cement, you want the electrical, and plumbing inspectors to let you know something isn't acceptable before you close up the walls.
Waiting to the end of the construction process to do safety audits sounds like an expensive mess likely to lead to a lot of
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Expensive but worth it in the long run (Score:2)
The capital costs of a reactor build are high because it's an expensive piece of construction, not simply because of delays etc. Every other large project including coal-fired and natural-gas generating plants also have to spend money up front preparing plans, covering the likely environmental impacts and dealing with protests.
Nearly all modern-build Gen-IIa and Gen-III reactors like the AP-1400, the EPR, ESBWR etc. are significantly larger than the original Gen-1 and Gen-II designs, each generating well ov
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Watts Bar Unit 2 was nearly finished in 1998, but was mothballed because it wouldn't make enough money. That's why the design is so old. It was started in the 1980s, but economics prevented it being finished. They were not about to scrap it and spend even more money just to do safety upgrades to a newer, safer reactor when the old design meets current regulations.
Nuclear's problems are all about money. Politicians and protesters are not very effective - if they were then we wouldn't have so many coal plants
Re: Stupid (Score:2)
Re:Stupid (Score:5, Interesting)
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This happens in private industry. Such is not exclusive to the military or government.
And yes, I've witnessed it, from inside and out. In private industry, government, and military. The NMCI was particularly affected by this.
Here are details regarding the need (Score:5, Informative)
Here are full details, with appropriate references, about the idea ending the reliance on fossil fuels in the US requires nuclear to be a significant part of the energy mix:
https://docs.google.com/docume... [google.com]
The summary is that solar, wind, hydro, and geothermal can make an important contribution, providing a significant portion of our energy needs. A very significant portion cannot be solved by those four choices - for reliable, steady power in huge amounts the choices are fossil fuels or nuclear.
almost done yet, so we can get off coal? (Score:2)
Argument? Still? Are you almost done arguing yet? Coal produces far more radiation than nuclear and far more CO2 than anything. Everybody pretty much agrees coal is the worst choice. So long as we continue arguing about how to stop using coal, we're largely stuck with coal until we decide. We've known this for a few decades, so I'd say it's about time we stop arguing and start doing the things we all know are better. Let me know when you're done with your mental masturbation and ready to get busy.
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we're largely stuck with coal until we decide.
As well as natural gas (methane)?
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Coal produces far more radiation than nuclear [...] /. already a 1000 times.
This myth got debunked on
so even the unicorn plan has 15% fossil or nuclear (Score:2)
> fossil carbon emissions would also shrink by 82-86% below their 2000 levels despite the assumed 2.58-fold bigger economy than in 2010.
So even if we assume EVERYTHING can be three times more efficient (good luck) AND we ignore the costs of trying to a accomplish that, STILL 15% of total energy can't come from renewables. And this is assuming renewable technology that doesn't actually exist, so it's really not an option right now, is it? Maybe it'll be available in 2050, but if we don't do anythin
...hours? (Score:2)
If an accident happens, the AP1000 will shut itself down without needing any human intervention (or even electrical power) within the first 72 hours."
I imagine that means the plant could be completely inactive (decay heat [wikipedia.org] will be down to the point of not requiring active cooling) within three days, but as written it's not reassuring.
And while "Generation II" sounds good, so were Fukushima and Three Mile Island. We should be building Gen 3-4 by now.
Re:...hours? (Score:5, Informative)
In order to ensure integrity of the containment, additional cold water would need to be pumped into the containment building roof tank within 72 hours. This could be by restoration of the electrical supply, use of diesel powered water pumps held on site, use of portable water pumps held near site, or by use of fire pumps.
The ESBWR which is the main competitor to the AP1000, meets the Gen3+ requirement of 72 hours of decay heat removal without operator intervention. Like the AP1000, no diesel or grid power is necessary to meet this requirement. Like the AP1000, the ESBWR has 2(N+1) redundant UPS systems with 72 hours of battery autonomy for shutdown control and monitoring equipment. However, the ESBWR has a 7 day reserve of cold water for containment cooling. In the event of operator inaction, the UPS batteries will deplete after approximately 72 hours, but passive containment cooling will continue for up to 7 days before water tanks would need to be replenished.
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Could they use the heated containment water to drive a Stirling engine which would pump more water?
I'm not a nuclear scientist (let alone a rocket scientist), but somehow it seems like there's a way to (relatively simply) use the heat from containment cooling to pump water.
And is there a reason the containment water couldn't be a loop with a cooling stage so it could be self-replenishing? It seems to make more sense if you consider the idea of the containment heat being used to drive pumps which circulated
Re:...hours? (Score:4, Informative)
There is a loop but it's the massive cooling tower. If however though the piping between the containment vessel and the cooling tower is destroyed you want a means of cooling outside of the intended infrastructure.
Re:...hours? (Score:5, Informative)
The backup cooling is a gravity fed system, once-through. The goal is simplicity for an emergency operation.
Anything more complex is really just duplicating the primary cooling system.
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Fukushima's reactors were a first-gen BWR design(believe it was reactors 1-4), and had been dealt with problems by the environmentalists and all that in terms of upgrading the plants themselves away from that design.
But CANDU reactors have had that built into them for years now, and are a ACR-1000 design, no power or power failure to either the SDS1 or SDS2 and the reactor automatically shuts down dumping 90% of the heat in under 2 seconds. I live within 60 miles of Bruce Nuclear(2nd largest nuclear plant
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will be down to the point of not requiring active cooling
Depends what you call active cooling!
Needing a pump? Or needing 'enough' water?
You did not read the link you quoted?
Spend fuel rods, or fuel rods removed for other reasons need water cooling up to 20 years!
From you link:
About 1 hour after shutdown, the decay heat will be about 1.5% of the previous core power. After a day, the decay heat falls to 0.4%, and after a week it will be only 0.2%.[1] Because radioisotopes of all half life lengths are present in nuclear waste, enough decay heat continues to be produced in spent fuel rods to require them to spend a minimum of one year, and more typically 10 to 20 years, in a spent fuel pool of water, before being further processed. However, the heat produced during this time is still only a small fraction (less than 10%) of the heat produced in the first week after shutdown.[2]
If no cooling system is working to remove the decay heat from a crippled and newly shut down reactor, the decay heat may cause the core of the reactor to reach unsafe temperatures within a few hours or days, depending upon the type of core. These extreme temperatures can lead to minor fuel damage (e.g. a few fuel particle failures (0.1 to 0.5%) in a graphite moderated gas-cooled design[3] or even major core structural damage (partial meltdown) in a light water reactor[4][5] or liquid metal fast reactor). Chemical species released from the damaged core material may lead to further explosive reactions (steam or hydrogen) which may further damage the reactor[6]
Re:...hours? (Score:5, Informative)
The plant has several electric pumps capable of transferring water from the bulk tanks to the containment cooling system, which could be connected to portable generators in a serious emergency. The plant also has multiple connection ports for portable pumps allowing water to be transferred into the containment cooling system from the bulk tanks or from fire engines/water tankers.
As the containment cooling tanks are at atmospheric pressure, only low pressure pumps are required, unlike at Fukushima where emergency response teams were trying to use pumps to inject water into the reactors at dozens of atmospheres of pressure.
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What happens if the pipework and valves that carry coolant to the reactor become damaged? Say you can't open the value to activate the backup cooling system, for example, or a pipe is broken and 50% of the water leaks out.
Admittedly earthquakes are less common where this reactor is being built, but earthquakes are not the only cause of that kind of failure.
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How is that long term extra cost reduced?
One way to reduce it is to allow the plant to come online years earlier, like it was supposed to, so that it could have been generating power all this time, covering the costs of building it and maintaining it, while also not burning carbon fuels. But because labotomized lefties WANT it to be expensive in order to try to make it unpopular, and of course the people designing the plant aren't cutting any corners, the only way to inflict harm is to throw up foot-dragging roadblocks to make the process more pa
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Thats just the cost of any private sector nuclear power site. The build cost has to factor in all the experts and nuclear only energy sub systems. The ongoing costs of buying bespoke nuclear parts adds to costs. Inspections then find expensive faults and complex parts need to be replaced. Finally the radioactive decommissioning costs have to be fully covered. Then the ongoing cooling ponds or o
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The power company says that construction was halted because energy was too cheap and it wouldn't have made enough money. Are you saying that they lied? If so, for what reason? Why would they try to divert blame away from "labotomized lefties"?
Your conspiracy doesn't make much sense. Take a look at electricity prices in the late 80s, they seem to agree with what the company is claiming.
Less is more? (Score:4, Insightful)
The article goes on for quite a bit about how much less "safety related hardware" newer plant designs have but I highly doubt that that says anything about how safe a reactor is or not. What DOES make a difference is fail safes, regular inspections, backups, emergency response plans, all with a design double checked by someone with a high school level of common sense. What has caused most of the major nuclear disasters? Rank stupidity. Fukushima was caused by the idiotic placement of backup generators and associated control hardware, in a basement and the subsequent failure of plant operators to call for necessary resources. Chernobyl was caused by them futzing with the reactor outside of normal operating procedures and then activating an emergency system that was not designed to handle those modifications. Three Mile Island was caused by a lack of appropriate sensors to recognize a lack of coolant in the reactor caused by a faulty relief valve. Knowing the reactor coolant level/pressure/temperature with certainty, having the ability to shutdown the reaction, and the ability to keep the reactor cool are the only things you need to prevent 99% of nuclear disasters. I'm not saying that designing a nuclear plant is easy, but keeping your backup cooling systems above water, not experimenting with a full sized nuclear reactor & knowing if your coolant is pouring out of a relief valve would seem to be no brainers that shouldn't have been missed.
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Fukushima was caused by the idiotic placement of backup generators and associated control hardware
That certainly exacerbated the problems are Fukushima, but was not the cause.
The earthquake damaged the plant, including the emergency cooling system and parts of the plant monitoring system. Then the tsunami did further damage and made inspecting critical parts of it impossible. Even after the emergency pumps failed, there was a working backup. They had fire engines on site that were pumping coolant into the reactors, or so they thought.
What turned an emergency into a disaster was the damage to the emergen
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The article goes on for quite a bit about how much less "safety related hardware" newer plant designs have but I highly doubt that that says anything about how safe a reactor is or not.
Actually it does. When using the HAZOP / LOPA techniques which have been common in plant design for years you consider every safety related device as a Layer Of Protection. If you're targeting a common residual risk, then having less Layers Of Protection implies the process is either of an inherently safer design (likelihood of risk is reduced) or that the consequence of a major incident is lower. This is fundamental to how safety related devices are assigned; you start with where you are, and where you wan
It has what nuclear plants need (Score:2)
And now, with electrolytes!
Lots of power (Score:5, Informative)
As I understand it the US has about 18GW of solar PV installed capacity with about a 28% capacity factor - so roughly 5 GW of actual power generation.
These two reactors together will generate about 2.2GW with a 90% factor, or around 2 GW.
One power plant, 40% of the capacity of all PV in the country.
Re:Lots of power (Score:5, Funny)
One power plant, 40% of the capacity of all PV in the country.
Well sure, but what happens when the sun goes down, causing that nuclear plant to stop generating power until the next morning, huh? How about THAT Mr. Smartypants?
Re:Lots of power (Score:5, Informative)
PV solar capacity factor for the U.S. is about 14.5% [wikipedia.org], about 18.5% for the desert southwest for fixed-mount panels. This is a physical limitation imposed by geometry, the movement of the sun, and typical weather conditions.
The 28% capacity factor the EIA gives for PV solar is for utility-scale PV solar installations. These generally track the sun and/or use concentrators (for some odd reason, capacity factor for PV with concentrators is calculated based on the panel's max generation without a concentrator - i.e. they can theoretically exceed 100% capacity factor).
Power generation for PV solar in the U.S. [eia.gov] for 2015 (Jan-Jul) has been 13,841 GWh. Divide that by the 5113.5 hours in 7 months and you get 2.7 GW average production. That's missing the fall and winter months for the latter half of the year so the average generation by December will be slightly lower than that. Doubling the Jan-Jun production yields an annual average of 2.6 GW. If you divide 2.6 GW by the 18 GW of installed capacity, you get a 14.4% capacity factor as expected.
These two new reactors will generate 77% as much power as all of the country's installed PV solar.
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WTF, what the funk.
Why is obviously everyone who uses the dreaded term 'capacity factor' such an idiot?
As I understand it the US has about 18GW of solar PV installed capacity with about a 28% capacity factor - so roughly 5 GW of actual power generation.
Politely speaking: you understand it wrong.
First of all you are mixing up GW with GWh ... very important, as the CF describes the relation between max ENERGY dvided by actual ENERGY produced by a plant.
Rest assured a 1GW solar PV plant will produce 1GW when t
This sounds really bad (Score:2)
"Compared to a Westinghouse Gen II PWR, the AP1000 contains 50 percent fewer safety-related blah, 35 percent fewer blah, 80 percent less safety-related blah, 85 percent less control blah, and 45 percent less seismic blah.
So if I get the math right, it sounds like it's 45% less earthquake resistant, 85% less under control, and ... carry the 1, 130-165% less safe all around. This makes me kind of nervous. But we got the facts -- at least that they're not spinning it to try to make the situation sound better than it is.
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So if I get the math right
You don't because having more stuff doesn't make a plant safer. A larger, more elaborate safety system is less robust than a smaller, simpler one. Less to go wrong means it's safer. A pump replaced with passie piping shapes is safer because there's one less pump to need emergency power and to break.
Makes you wonder (Score:2)
So why does it take so effing long to approve this? What if the delays are engineered, no pun intended, to make the reactor obsolete before it ever gets brought online?
Re:Hooray! (Score:5, Interesting)
I've been to a couple of commercial construction sites (ie, mostly steel and concrete, versus wood for residential) where construction had stalled for a couple of years after the property value collapse, and crews were literally having to break-up concrete because unfinished exposed rebar ends had rusted and that rust expanded the rebar down into the concrete, causing cracks to begin in that concrete.
That was after only a couple of years. Imagine how bad it would get after close to 30 years. Buildings already have enough problems when they're finished if they don't get regular maintenance over the course of decades, but unfinished buildings that are not environmentally sealed will undoubtedly fare far, far worse.
I know that nuclear reactors are supposed to be structurally overengineered simply due to the nature the forces they contain, but starting out with a handicap due to building structural problems doesn't sound like the greatest plan, and that's before account for all of the other technical changes that have been engineered through the decades. We've already seen problems in younger reactors that were finished approximately on their original timetables, this seems like it's asking for more.
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It was 80% complete when work halted. That likely means the walls were closed up and a roof was on.
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It took them 8 years to get the final 20% done?
They should have just started over with a Gen 3 reactor.
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I imagine a decent chunk of that time was spent on inspection and repairs.
Re:Hooray! (Score:4, Informative)
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We had one near us too. They tore it down after sitting two years.
Re:Hooray! (Score:5, Informative)
A couple of comments. I worked at Watts Bar for 6 years - from just before they restarted construction until 2013. I now work out at one of the new reactors under construction at VC Summer.
First off, WBN2 and WBN1 share structures. Actually, all the structures except for the reactor building itself is shared. The units are what is considered an "opposite hand" configuration, which means that essentially a piece of equipment, piping, or valve on the far west side of the plant for U1 would be on the far east side, at the same northing, for U2 with everything matching up in the middle. The units also share many systems, and in order for them to start up U1, they had to have those systems (and many of the U2 pumps, valves and other support equipment) in service. The units also share a control room, spent fuel pool, diesel generators, and more. The only completely independent structure is the reactor building, which was structurally complete when they halted construction. Most everything inside was complete (major equipment set, piped in, etc). Most of what was lacking were control systems, instrumentation, and some valves. Also, all of this equipment was under temperature and humidity controls during the layup period.
One other thing - all of these structures are reinforced concrete. The unique thing about concrete is they get stronger with age unless you have something like saltwater causing problems. They're also *very thick* and *heavily reinforced* concrete - as in, the age isn't a handicap at all.
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Try reading slower. If you have to move your lips, that's ok.
Alternatively, graduate 9th grade. Even by today's standards, that should be enough.
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Please think of the stray dogs.
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Crumbling concrete, vegetation encroachment, animals nesting, water incursion, and it goes on and on. Two windows were vandalized by bullet holes and someone painted a swastika on a rolling door.
If only there were a way to fix stuff.
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And certainly the plywood is ruined.
Re:Less Valves etc (Score:5, Insightful)
My car has two doors, does that make it less safe then a car with 4 doors?
Well yeah, if you had to go through all of them to get out...
Other way. Less likely to have a door problem. (Score:2)
The other way around. Simpler is more reliable. Suppose that each year, 1 door of 1,000 fails. Your car has two doors, so the odds you'll have a door failure are 2/1000, or 1/500. My car has four doors, so the odds that one of mine will fail is 4/1,000, or 1/250.
It may be easier to see with more extreme numbers. Your car engine probably didn't fail this year. Dallas Texas has a couple million car engines. It's virtually certain that some failed.
More parts means more chances for failure. Perhaps more impo
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Pedant Mode...ON.
More properly, the failure rate of two doors in your example would be 1 - (999/1000)^2. For four doors, it would be 1 - (999/1000)^4.
Which gives you numbers pretty close to the 1/500 and 1/250 you mentioned. The divergence incre
double pedanticly, my numbers are right (Score:2)
I had said "the odds you'll have a door fail". You gave the odds that you'll either have A door fail, or have TWO doors fail. :)
That's actually my favorite question in probability:
You enter two contests. You have a 1/10 chanfe of winning each contest. What is your overall chance of winning?
It sounds so simple, yet it's devilishly difficult to figure out if you don't already know the trick, that you have to instead figure out the overall odds of LOSING both.
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That's a large, and usually false, assumption. A plane with 2 engines, capable of flying on 1, may well have a higher chance of an engine failure but it is no less reliable as a plane (each engine is equally reliable, and the plane is more reliable). It is also considerably safer as the risk of mechanical failure leading to a crash are massively lower.
Decent reactor design will, one assumes, mean that they add additional valves etc because they lower the ris
note the asterisk. Then compare Subaru on aircraft (Score:2)
Perhaps you didn't note the asterisk in my post. Yes, redundant identical parts often increase overall system reliability (though they create new modes of failure - ie load balancers can have problems).
As I said the reactor designs BOTH incorporate redundancy, so that doesn't account for the difference in parts count. The newer design is truly _simpler_ with fewer interactions that can go wrong.
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50% less safety valves' for example. What does this mean?
The context is known for any kind engineer who's worked in the industry. 50% less safety valves to meet the same safety requirement means that an inherently safer plant design is used and that only half of the layers of protection are required to reduce the process risk to a residual level.
Providing the residual level of risk is the same for all analysed plants, safety can absolutely be determined by such numbers. Less layers of protection for the same risk means:
1. Safer underlying process.
2. Lower liklyho
Re:42 YEARS!?? (Score:5, Funny)
To be fair, the 42 year delay was so that they could convince the people of Tennessee that electricity wasn't the work of the devil.
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"To be fair, the 42 year delay was so that they could convince the people of Tennessee that electricity wasn't the work of the devil."
No, the time was spent vainly trying to convince liberals of that fact.
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Liberals love electricity, because it is so much cleaner than burning fossil fuels for transportation. I don't know if I'm the kind of person you are referring to, but I'm often accused of being a foaming at the mouth raving environmentalist so I'll guess that maybe I am, and I drive an electric car. I love electricity.
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So why don't you people let us generate more of it? And let us build the electric alternative infrastructure, like the high-speed rail being described here, that would cut down on our use of petroleum.
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I'm a massive proponent of high speed electric rail. I think it's great, and want more of it built. High speed rail is very environmentally friendly, as it replaces cars and airplanes for many long journeys.
I think you are confusing environmentalists with NIMBYs.
As for generating more energy, it's generally cheaper to save energy, and at the moment the goal should be to replace what we have with cleaner stuff. We don't really need more - in western Europe and parts of the far East demand is falling because
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As the other guy said, you're confusing environmentalists with NIMBYs, but also, you're confusing two groups of environmentalists. The smart environmentalists are pro-nuclear, or at least, anti-coal and anti-fossil-fuel and in favor of nuclear as an alternative to those for the time being until better sources can be made more economical.
Yeah, unfortunately there's a bunch of dumb anti-nuclear people out there who don't want any nuclear power, but don't have any suggestions at all about what to do to make t
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All of the small renewable energy sources are location-dependent. Some places are sunny, others are windy, and occasionally you will find an old volcanic stump with residual geothermal heat. These sources will certainly help, especially in applications that can tolerate fluctuating power, such as charging EV batteries. But now what if your "smart environmentalists" are right about climate? If we really have to eliminate fossil sources in one generation, only nuclear will make up for the massive baseload we
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If we really have to eliminate fossil sources in one generation, only nuclear will make up for the massive baseload we now have in coal and gas.
Yes, exactly. I think I said this in my post above basically: that renewables + nuclear is a practical and relatively environmentally-friendly way to meet our electricity needs now and into the near future. Over time, we should be able to come up with more efficient and cheaper solar cells so that that can be used more and more, and older nuclear plants can be de
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You realize most of the electricity used for transportation comes from burning fossil fuels ?
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Sadly, that's true at the moment. Even so, it's still better than burning fossil fuels in the vehicles themselves.
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http://www.gizmag.com/audi-cre... [gizmag.com]
So how do you feel about burning carbon made from electricity and CO2 ?
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To be fair, the 42 year delay was so that they could convince the people of Tennessee that electricity wasn't the work of the devil.
"I've never seen electricity, so I don't pay for it. I write right on the bill, 'I'm sorry, I haven't seen it all month.'" - Steven Wright.
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The people of Memphis and Nashville are welcome. All others pay cash.
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What about folks from Bucksnort? Or folks from Lynchburg bearing delicious gifts?
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Yeah, the TVA sure didn't convince them.
Nor did the streetlights, or the Grand Ol Opry, or WSM. Admittedly, they may have been using battery radios in the hills.
Re:Message from Greens (Score:4, Funny)
No, that's a message from Bruce Dickinson.
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Did you notice it was delivered at twelve minutes to midnight? Ten minutes early.
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You can't shutdown the spent fuel (waste) radioactive decay