RichPhitzwell
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Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 2:37 pm

seemed like a new thread is necessary instead of hijacking the memorial thread found here
21st Anniversary Of Chernobyl Disaster (by Levg79 Apr 26 2007 in Non Aviation)
Nonav.com kinda like Whiners except the lights are on and the pimps been paid
 
ZBBYLW
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 3:04 pm

Well I think the positives would be, a clean source of energy. Negatives being well Chernobyl type events or the Nuclear waste left over.
Keep the shinny side up!
 
DfwRevolution
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 3:27 pm

Advantages:
- generation of electricity produces no carbon, nitrous, sulfuric, or mercury pollution
- excellent source of base power supply

Disadvantages:
- high upfront investment
- strict oversight and regulation
- long-term disposal of waste

I am disappointed that nuclear fission fissiled as rapidly as it did post Three Mile Island and especially post Chernobyl. The Chernobyl disaster itself is virtually impossible due to western reactor design and the fact that safety was a word rarely taken seriously in the former USSR.

The generation of electrical power is one of the greatest contributors to both the pollution that could be leading to climate change and the foreign energy dependence that haunts the U.S. As it happens, the U.S. has some of the highest abundance of uranium ores in the world. I certainly wish solar PV and wind could provide the base power loads we need, but they simply can't with the technology available at present. That leaves nuclear as the only emissions-free source of base power.

The green crowd screams about radiation and waste disposal, but our coal power plants are spewing more radioactive isotopes into the atmosphere than any nuclear power accident to date. Getting those plants offline should be a top priority for the environmental front. What they need to realize is that there is no "perfect" source of power yet, but nuclear fusion is a huge step in the right direction. With properly regulated waste recycling, we could start putting a real dent in pollution and fossil fuel demand without the frivilous airline taxes and one-piece-of-toilet-paper programs we have seen to date...
 
Springbok747
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 5:23 pm

Its 'Nucular', not 'Nuclear'..ok?  Wink

Advantages:

Clean
Fuel is inexpensive
Waste is more compact than any source
More $$$$ to the Australian govt

Disadvantages:

Requires larger capital cost because of emergency, containment, radioactive waste and storage systems
Problem with storing high-level waste (unless of course you dump it in the middle of the Outback here)
Potential nuclear proliferation issue
Uranium is not renewable
אני תומך בישראל
 
jwenting
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 6:28 pm

Quoting DfwRevolution (Reply 2):
- strict oversight and regulation
- long-term disposal of waste

The two are closely related...
The longterm disposal wouldn't be a fraction of the problem it is today (literally!) if the regulations were more sensible.

As it is it's not allowed to refine fuel for nuclear powerstations from nuclear waste despite it being quite possible to use a lot of that waste as fuel for rapid breeder reactors.
If it were allowed the volume of waste that needs to be stored would go down to a fraction of what it is today (and even today it's no more than a few cubic meters per year for most reactors).

The anti-nuclear lobby has been highly successful in giving people the false belief that every nuclear powerstation is an atomic bomb waiting to go off and is producing tons of weapons grade plutonium each year.
Nothing could be further from the truth (though 1940s style reactors like the ones at Chernobyl are dangerous, such haven't been used in the west since the 1950s).

Quoting Springbok747 (Reply 3):
Uranium is not renewable

That is correct. It's however in large enough supply that it can last until something better is found. It also reduces our depence on the unstable regions of the planet for energy (middle east, Venezuela, Russia), which in itself is IMO an excellent reason to use it.

And there is no truly renewable source of energy anyway. Windmills need raw materials and effect weather patterns in ways we're only now starting to understand (effects which are silently ignored by the environmentalist lobby).
Same with solar, which is also extremely polutant when disposing of used up solar collectors and solar cells as they contain large amounts of plastics and heavy metals).
I wish I were flying
 
raventom
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 6:29 pm

Advantage:

It is not weather relliant like most renewable sources.
I love the smell of burnt kerosene!!!!!!!!!!!!
 
767Lover
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 7:19 pm

I'm all for nuclear energy. However, my understanding is that the operational costs are just enormous in terms of employee procedures and training. I have a friend who used to work out at the Vogel site in Georgia and the amount of time and "stuff" he had to go through every time there was even the slightest indication of contamination -- well it just seems impractical and this stage, unfortunately.

Quoting DfwRevolution (Reply 2):
Getting (coal) plants offline should be a top priority for the environmental front.

It is not that simple. Honestly. The truth is that we don't have enough production capacity in place in the US to replace those plants if they were just switched off. Replacing them is an major problem due to the fact that it is near impossible to get a permit for a new plant due to all the NIMBY-ing. Even if a permit were available, it would be nearly 10 years before a new plant would come online due to all the clearances and rules.

I hear what you are saying but sound bites don't tell an accurate story.
 
galapagapop
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 9:27 pm

It's clean burning, but problem is, even with new Uranium mines popping up in UT and NV and of coarse the large ones in Kazakistan, Uranium supplies at current use rates, last only about 75 years. Surely that will rise as new mining locations are found but this does not include the expected surge in nuclear reactors to come on line domestically and internationall over the next 20 years. BTW if anyone neeeds a new major, I'd go to be Nuclear technicion, you don't need to be a rocket scientist though. But let me tell ya if you want a good paying job, let's do the math. Average age of current Nuclear powerplant workforce? 55+, new plants expected domestically and internationall in next 5 years? 10+, number of jobs needed to be replaced in next 10 years with new anum growth? 20,000+ for a job largely ignored since the 70's and 80's.

 Silly
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 11:22 pm

Quoting DfwRevolution (Reply 2):
Advantages:
- generation of electricity produces no carbon, nitrous, sulfuric, or mercury pollution
- excellent source of base power supply

Disadvantages:
- high upfront investment
- strict oversight and regulation
- long-term disposal of waste

I

 checkmark  A succinct list, although the spent fuel is less of a problem than you might think. Another point I would have added is the cost of adhering to the Linear No Threshold (LNT) theory which underpins the current International Committee on Radiological Protection (ICRP) requires members of the World Association of Nuclear Operators (WANO) to adhere to. This means in principle that any exposure to radiation is harmful and that members policy should be "as low as is practically possible" in terms of exposures. This costs the industry billions annually in costs and this is reflected in electricity rates.

No self-respecting scientist (that I know) believes in LNT anymore, there's simply no real evidence to support it. But, it's a political and PR position that ICRP has taken, and WANO has basically grabbed its' ankles on this issue. Below about 50 Rem exposure, there seems to be zero effect on a human being. After all, our species has evolved on a planet that is naturally radioactive. There's all manner of radioactive sources out there, from K40 to radon to uranium & thorium in various granite/gneiss formations, and on and on. If it was that dangerous, we wouldn't be here in the first place.

As for waste management, well, for CANDU reactors, we only extract about 1% of the available energy from the fuel when it exits the reactor (for a number of reasons). It would ne nice to get more out of the fuel in order to extend the length of time we have uiranium available. That means reprocessing, which has a number of tough chemical engineering issues, and with current technology produces a lot of radioactive liquid waste. But the point is, again looking at CANDU, the spent fuel in about 700 years is back to the radiation levels it had when the U3O8 ore came out of the ground. More preferable to me is medium-term above ground storage in concrete/steel canisters -- which we're starting to do here in Canada. It's cheap, it's quick, and it leaves a resource available for future use.

Quoting 767Lover (Reply 6):
'm all for nuclear energy. However, my understanding is that the operational costs are just enormous in terms of employee procedures and training. I have a friend who used to work out at the Vogel site in Georgia and the amount of time and "stuff" he had to go through every time there was even the slightest indication of contamination -- well it just seems impractical and this stage, unfortunately.

Good to hear. See my point above about radiation dangers & protection. This costs an _enormous_ amount of money, and is a good example of the 90/10 rule: 90% of the costs are created to ensure the last 10% of protection -- which most of us think is completely pointless.

Quoting Galapagapop (Reply 7):
But let me tell ya if you want a good paying job, let's do the math. Average age of current Nuclear powerplant workforce? 55+, new plants expected domestically and internationall in next 5 years? 10+, number of jobs needed to be replaced in next 10 years with new anum growth? 20,000+ for a job largely ignored since the 70's and 80's.

That is an EXCELLENT point. This is likely the single biggest problem in the nuclear industry - we're old. No real hiring has occurred for a long time, sonce many viewed it as a sunset industry. So, retirement is looming for a big fraction of the people currently employed there, including me. We need to hire, mentor, and train _tons_ of new people in all areas: engineering, physics, chemistry, design, you name it. So I would say to anyone reading this thread who is looking to make a career decision, look at the nuclear power business.
Nostalgia isn't what it used to be.
 
UALPHLCS
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RE: Advantages And Disadvantages Of Nuclear Energy

Sat Apr 28, 2007 11:32 pm

Quoting DfwRevolution (Reply 2):
Disadvantages:
- high upfront investment

Part of the high upfront investment cost however, is the fact that nuclear power plants haven't been built in the US in 30 years.

France get the vast majority of their power from nuclear. I'm sure that an analysis of their up front cost would show that it's not as expensive as it is here in the US.

Further Disadvantages are:

NIMBY No one wants to have one near them. and the threat of terrorism against a plant.

I think the safety concerns are over blown. The US Navy has been successfully using nuclear power for over 50 years. That's a lot of expertise out there in the marketplace.

The main problem is the waste. The Yucca mountain plan is a good plan. There again you have NIMBY blocking the path of progress.
A little less Hooah, and a little more Dooah.
 
galapagapop
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 6:47 am

Quoting Connies4ever (Reply 8):

Correct me if I'm wrong but doesn't it not take that long to be certified to work basic tech or core positions? And also do you have any ballpark of starting salaries for say a 4 years college grad? Figure's that pop into my mind are 55-65k but I know I'm off somewhere, but either way I've considered it. It's similar to the FAA in their problems with ATC controllers and the looming shortage in 10 years as well, except their schools are fairly full, and unlike the FAA the nuclear power industry is in private hands so salaries won't lag the demand curve. Lucrative either way!
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 6:56 am

Quoting Galapagapop (Reply 10):
Correct me if I'm wrong but doesn't it not take that long to be certified to work basic tech or core positions? And also do you have any ballpark of starting salaries for say a 4 years college grad? Figure's that pop into my mind are 55-65k but I know I'm off somewhere, but either way I've considered it. It's similar to the FAA in their problems with ATC controllers and the looming shortage in 10 years as well, except their schools are fairly full, and unlike the FAA the nuclear power industry is in private hands so salaries won't lag the demand curve. Lucrative either way!

For a tech position, a 2-3 yr program is sufficient, starting salaries (in Canada) are in the 42-45K range. For a 4-yr university grad (engineer usually, but physiccs/chemistry also) around 55-60K, so you are in the ballpark. Salaries from what I can tell in the US market are a little higher. If you have a post-grad degree, then you get bumped fairly well. Also puts you more likely on the road to management, if that's your goal.

Unlike the US, in Canada all nuclear, with one exception, is provincially-run (Ontario, Quebec, New Brunswick). The exception is Bruce Power, which is a private consortium created to operate the Bruce Nuclear Generating Station (largest in the world). BP _lease_ the station from the provincial utility and sell the power back to them.

I don't believe you'd go wrong going down this road. One utility in the US that I know is serious about new nuclear is Dominion Energy in Virginia. They've kicked the tires on our new product, but I truly believe they will purchase the Westinghouse AP1000.
Nostalgia isn't what it used to be.
 
DfwRevolution
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 9:13 am

Quoting DfwRevolution (Reply 2):
What they need to realize is that there is no "perfect" source of power yet, but nuclear fusion is a huge step in the right direction

Just an edit that I'm surprised no one else noticed, but that above statement should regard nuclear fission!  Wink

Quoting 767Lover (Reply 6):
It is not that simple. Honestly. The truth is that we don't have enough production capacity in place in the US to replace those plants if they were just switched off.

And I never implied that it was a simple problem. However, if there is any energy source that is capable of replacing the majority of combustion-based power generation, the best we can do with present technology is nuclear fission.
 
galapagapop
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 9:38 am

Quoting DfwRevolution (Reply 2):
nuclear Fusion

I find fission very promising, but fusion is as well, if not more so. The fusion of Deuterium and Tritium is very beneficial and efficient. Although Tritium is a low level radioactive element, it's got a 12 year half life with only a few Kg naturally in existance, so we will artificially make it, from Lithium bombarded with nuetrons to form Tritium with a byproduct of Helium, which is an excellent by product, as Helium is a depleting resource with not many new wells being found and much just going into the atmosphere, it can help prevent a He shortage in the next 20 years if it becomes widely produced. Lithium and Deuterium are very common in the enviroment and should make fusion viable, although by no means a free energy.
 
Yellowstone
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 9:55 am

Quoting Galapagapop (Reply 13):
but fusion is as well, if not more so

Except that the technology has been "30 to 50 years off" for the past 30-50 years.
Hydrogen is an odorless, colorless gas which, given enough time, turns into people.
 
galapagapop
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 10:04 am

Quoting Yellowstone (Reply 14):
Except that the technology has been "30 to 50 years off" for the past 30-50 years

True but they are finally starting to test and better implement the magnetic fields needed to have fusion contained. Before it was more of theory and understanding it would work, but there had been zero practical implementation of a proper chamber with a magnetic field that can support 100mil degrees of fusion particles, not to mention the sensoring equipment and the understanding of best elements to use (from day 1 it wasn't Deutrium and Tritium, took lots of tests.) I'm sure it won't be online by 2020 or probably 2030. But hey most large scale energy ideas aren't in full practice either and won't be for a loooooong time.
 
andessmf
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 11:43 am

Quoting DfwRevolution (Reply 2):
Disadvantages:
- high upfront investment
- strict oversight and regulation
- long-term disposal of waste

This still applies to most conventional plants as well, if to a lesser degree. Nuclear power in the West (especially Europe) has had a safe enough history to make it a better option than others.
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Sun Apr 29, 2007 1:00 pm

Quoting AndesSMF (Reply 16):
This still applies to most conventional plants as well, if to a lesser degree. Nuclear power in the West (especially Europe) has had a safe enough history to make it a better option than others.

I don't know about that. The Siemens gas-fired systems are pretty cheap up front but have (potentially) very high operating costs. They are also modular so that you can install (I think the power rating is) 180 MW at a time, as you need it. Construction time is usually about 18 months.
Nostalgia isn't what it used to be.
 
DrDeke
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 12:09 am

Quoting Connies4ever (Reply 17):
I don't know about that. The Siemens gas-fired systems are pretty cheap up front but have (potentially) very high operating costs. They are also modular so that you can install (I think the power rating is) 180 MW at a time, as you need it. Construction time is usually about 18 months.

Yeah, natgas fired power plants are pretty slick pieces of engineering. They are essentially large turboshaft engines with generators connected to their shafts, and then if the utility is smart, and if the plant will be run for more than just peak demand times, they use the (large quantity of extremely hot) exhaust gases produced by the gas turbine to fire a secondary boiler which is then piped to a steam turbine for further electrical generation (and/or district heating/cooling, etc). As far as power plant cycles go, it's quite efficient.

However, it strikes me as slightly nuts to burn natural gas for base load utility power in most circumstances. As has already been mentioned, the fuel is not cheap. It also strikes me as a wiser idea to save natural gas for applications like domestic heating, domestic water heating, and so on. We don't want to go back to having plumes of soot coming out of our houses from our coal furnaces, do we? It seems to me that it would be a lot cheaper and more effective to burn coal in base load power plants and install cleaning/scrubbing/etc apparatus, the cost of which would be absolutely prohibitive for individual homes.

DrDeke
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connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 12:22 am

Quoting DrDeke (Reply 18):
However, it strikes me as slightly nuts to burn natural gas for base load utility power in most circumstances. As has already been mentioned, the fuel is not cheap. It also strikes me as a wiser idea to save natural gas for applications like domestic heating, domestic water heating, and so on. We don't want to go back to having plumes of soot coming out of our houses from our coal furnaces, do we? It seems to me that it would be a lot cheaper and more effective to burn coal in base load power plants and install cleaning/scrubbing/etc apparatus, the cost of which would be absolutely prohibitive for individual homes.

Nat gas might be better used for feedstock to make synthetic materials, and leave oil for refining to motive fuel and lubricants. As for coal, I am interested in the cleam coal/'carbon sequestration idea, and I believe a demonstration plant is being (or is planned) for the Long Beach area. Something on the order of 250 MW. If this works, it pretty much reduces greenhouse gas emissions to a minimum, and also has the by-product of producing H2, which can be used for other purposes.
Nostalgia isn't what it used to be.
 
ltbewr
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 12:47 am

In the USA, although about 20% of electricity is from Nuclear plants, there are still strong objections as to Nuclear electricity generating or expanding it. In France, I believe that number is over 60%. The last plants were started up over 25 years ago in the USA, and a number of planned plants failed to ever be completed or even started. Some sites turned out to be in high risk areas for earthquakes. The events at Three Mile Island and Chernobyl, that plants could be terror targets, the problems with handling and long term storage of the very hazardous spent fuel all work against it and creates a massive NIMBY attitude even worse than for 'conventional' plants, including coal, oil and Natural gas. Many USA plants are approaching or are already beyond their planned safe time of use. If I am correct, Sweden and some other countries plan to de-comission all of their current nuclear power plants due to the risks of them.
You also have the massive financial resources needed to build nuclear power plants today. Back in the 1980's, the Washington State Power Authority defaulted on it's notes to be used to fund new nuclear plant building with Billions in losses to taxpayers and investors. Since the start of nuclear power in the USA, those power plants have been exempt from their losses if something should happen - that it would be the obligation of the Federal government to pay for damages.
There is considerable investment in the USA being made by power suppliers and the makers with politicians and government agency lobbing to allow for new nuclear power plant production, even if people don't want it. Yes, nuclear power doesn't put out CO2, dust, fumes or other short and long term risks but some consider the risk too high vs. conventional means.
 
TedTAce
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 1:00 am

I like Nuclear for an ALTERNATIVE.

Our primary energy sources should be water (sea and dams) and solar. Then wind (preffer offshore), Then Natural gas, then nuclear, and if it's ABSOLUTELY necessary (national emergency of epic proportions) coal. We also should be pressuring the PC industry, TV industry, and the lighting industry to come up with even cheaper (consumption wise) alternatives. Transportation is a HUGE PROBLEM and we REALLY need to get ahead on the curve for alternatives. We will eventually run out of JP8 (not in our life times but eventually) and if we don't find an alternative we are going to be screwed.

Needless to say, I'm VERY much for anything that can isolate us from being dependent on others for our needs.
This space intentionally left blank
 
WSOY
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 1:37 am

The world's most powerful reactor (1600 MW) unit is now being built at Olkiluoto, western Finland, due to start generating in 2011. A montage picture of the whole future power station area is below. The existing two 880 MW reactors are on the foreground.
The preparations for a third unit have recently been initiated on the other nuclear power station location in Loviisa on the south coast, which now has two Soviet VVER-440s (run at 488 MW).



more
"Nukkuessa tulee nälkä" (Nipsu)
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 2:51 am

Quoting LTBEWR (Reply 20):
read 28 times:

In the USA, although about 20% of electricity is from Nuclear plants, there are still strong objections as to Nuclear electricity generating or expanding it. In France, I believe that number is over 60%.

I think you'll find in the latest polling that a majority of Americans are either in favour of nuclear or 'accept it will be part of the energy mix' (which I guess is code for "Don't bother me with important issues"). It's very similar in Canada and is a marked change from 15-20 years ago. The fear-mongers are gradually losing the argument to the people with the facts.

BTW, for France the nuclear fraction is 80%. And it has the cleanest air in Europe.

Quoting TedTAce (Reply 21):
Our primary energy sources should be water (sea and dams) and solar. Then wind (preffer offshore), Then Natural gas,

Sea power (usually called OTEC) is a very interesting possibility, but there are many problems to solve before it can be reliably deployed. No more hydro dams !!! They cause a lot of environmental damage not to mention they create large mercury problems upstream, as well as a (short-lived) but significant greehouse gas burst. The northern part of my home province has been ruined by these things. Natural gas costs way too much, given the current market, and the people who are pushing LNG in my view are simply insane. If an LNG tanker were to have an accident wherein it lost pressurisaiton/containment, it _would_ be like an atomic bomb going off.

If you want to look into sometihng that's available forever (well, OK, as long as Earth exists) check out geothermal energy. If you're going to build a new house, as I plan to do in about 2 years, that's the way to go.
Nostalgia isn't what it used to be.
 
PPVRA
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 3:06 am

Quoting Connies4ever (Reply 23):
Sea power (usually called OTEC) is a very interesting possibility, but there are many problems to solve before it can be reliably deployed.

I think what he meant were off-shore wind farms. I haven't heard of this OTEC technology.

http://www.runet.edu/~wkovarik/envhi...ean.pix/ioes.saga-u.indea-otec.jpg

http://en.wikipedia.org/wiki/OTEC

Very interesting.

[Edited 2007-04-29 20:07:43]
"If goods do not cross borders, soldiers will" - Frederic Bastiat
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 3:52 am

Quoting PPVRA (Reply 24):
I think what he meant were off-shore wind farms. I haven't heard of this OTEC technology.

I believe the Israelis have a proof-of-concept OTEC setup in the Dead Sea, and there is of course the one in Hawaii. I forgot to include in my reply to TedTAce that ocean tidal power is a possibility (and I think this is what he meant) that should be evaluated seriously.

Yes, OTEC is a very interesting idea.

Many people think wind power is the asnwer to all our problems. It isn't, and it is already causing big problems in Europe. In Germany, for example, E.ON, a major power supplier, says because of the large amount of wind generation in the grid, they need nuclear to stabilize the grid. Power grid management is a real big issue and if you have too much variable generating capacity in one area, and it goes off the radar, you tend to get grid fluctations that can take the whole thing down -- part of the reason for the big outage in Eastern North America in August 2003. If you don't have nuclear available, then you're left with leaving coal/gas-fired plants on hot standby to step in. That makes a huge amount of sense, doesn't it ? And, it's not like flipping a switch, these plants need some time to come up to nominal operating conditions and feed power into the grid. Wind has its' applications, especially for isolated locations, but I don't see it ever being a primary source, and I think it would be a big mistake if it did.
Nostalgia isn't what it used to be.
 
galapagapop
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 5:05 am

Quoting TedTAce (Reply 21):
Our primary energy sources should be water (sea and dams) and solar

Ted, if we learned anything from NOLA besides FEMA's incompetence is that messing with water sources for our own benefit hurts us in the long run. Rivers, streams, and the oceans serve a purpose and that is not to be dammed up and re-routed for our use. The Hover dam, through no fault of it's own, is seeing record low water levels anyway, making the whole concept no longer air tight, if we as a people cannot first protect the river itself, why should we pilfer if further, even if it's simply a matter of taking advantage of gravity. Solar is not a viable option until overal consumption is reduced. Right now it's way too expensive and way to ineffecient for anyone to benefit from. Gas isn't good either as it's expensive and can far more effeciently be used by industry.

Personally my list is: Nuclear, Incineration of trash (which can simply mean of organic trash that creates methane), then Geothermal plants, which although are using mother nature can be used to help vent backed up heat and pressure from under the Earth's crust, then Dams, then Coal, then Solar, and then if needed oil or gas.

Cheers!
 
lehpron
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 9:59 am

Quoting DfwRevolution (Reply 12):
Quoting DfwRevolution (Reply 2):
What they need to realize is that there is no "perfect" source of power yet, but nuclear fusion is a huge step in the right direction

Just an edit that I'm surprised no one else noticed, but that above statement should regard nuclear fission!

That is because when most people think of nuclear, they either only think of fission or they do know of any other and don't bother informing themselves. Granted it is difficult (but not impossible) to make fusion more stable, but that is no reason to cop-out and go for fission only because it has been proven as a cheaper alternative.

I suggest researching the 3rd nuclear alternative: Antimatter.  Wink Bad enough most people are stupid ill-informed to honestly think I'm talking sci-fi
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
baroque
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RE: Advantages And Disadvantages Of Nuclear Energy

Mon Apr 30, 2007 12:30 pm

Quoting DfwRevolution (Reply 2):

The green crowd screams about radiation and waste disposal, but our coal power plants are spewing more radioactive isotopes into the atmosphere than any nuclear power accident to date. Getting those plants offline should be a top priority for the environmental front. What they need to realize is that there is no "perfect" source of power yet, but nuclear fusion (ED FISSION??) is a huge step in the right direction. With properly regulated waste recycling, we could start putting a real dent in pollution and fossil fuel demand without the frivolous airline taxes and one-piece-of-toilet-paper programs we have seen to date...

Indeed, I tried to post along these lines in the Chernobyl thread and got deleted for my pains!

Quoting Connies4ever (Reply 8):
A succinct list, although the spent fuel is less of a problem than you might think. Another point I would have added is the cost of adhering to the Linear No Threshold (LNT) theory which underpins the current International Committee on Radiological Protection (ICRP) requires members of the World Association of Nuclear Operators (WANO) to adhere to. This means in principle that any exposure to radiation is harmful and that members policy should be "as low as is practically possible" in terms of exposures. This costs the industry billions annually in costs and this is reflected in electricity rates.

No self-respecting scientist (that I know) believes in LNT anymore, there's simply no real evidence to support it. But, it's a political and PR position that ICRP has taken, and WANO has basically grabbed its' ankles on this issue. Below about 50 Rem exposure, there seems to be zero effect on a human being. After all, our species has evolved on a planet that is naturally radioactive. There's all manner of radioactive sources out there, from K40 to radon to uranium & thorium in various granite/gneiss formations, and on and on. If it was that dangerous, we wouldn't be here in the first place.

As for waste management, well, for CANDU reactors, we only extract about 1% of the available energy from the fuel when it exits the reactor (for a number of reasons). It would be nice to get more out of the fuel in order to extend the length of time we have uranium available. That means reprocessing, which has a number of tough chemical engineering issues, and with current technology produces a lot of radioactive liquid waste. But the point is, again looking at CANDU, the spent fuel in about 700 years is back to the radiation levels it had when the U3O8 ore came out of the ground. More preferable to me is medium-term above ground storage in concrete/steel canisters -- which we're starting to do here in Canada. It's cheap, it's quick, and it leaves a resource available for future use.

You outline elegantly some of the basic problems leading to the way in which fission stations have had major PR problems. Obviously severe doses of radiation are dangerous, but seeking zero radiation apart from being impossible, may actually be more dangerous than the natural levels that we normally get.
For the disposal of radioactive waste, clearly re-use is the best option. Failing re-use, there are disposal methods better than the ones proposed early in the history. Borosilicate glasses suffer from the problem of devitrification followed by leakage. Storing in salt beds does not seem a bright idea to this observer. First, salt is highly corrosive, secondly salt beds have surprisingly large amounts of mobile water and thirdly, salt beds are potentially highly mobile. The attempt to use the Hutchinson Salt Beds in Kansas was quite bizarre. For a start the beds are quite thin and secondly, they are punched full of holes for oil wells, many unlocated.
There is a disposal method that has been tested. This is the late Ted RIngwoods development of Synrock. He observed that minerals such as zircon have a high content of radioactive elements but are physically stable over billions of years - apart from the development of metamict structures. Disposal using synrock is relatively expensive, but better affordable expense than going on and on about there being no means of disposal.

Quoting Galapagapop (Reply 15):
Quoting Yellowstone (Reply 14):
Except that the technology has been "30 to 50 years off" for the past 30-50 years

True but they are finally starting to test and better implement the magnetic fields needed to have fusion contained. Before it was more of theory and understanding it would work, but there had been zero practical implementation of a proper chamber with a magnetic field that can support 100mil degrees of fusion particles, not to mention the sensoring equipment and the understanding of best elements to use (from day 1 it wasn't Deuterium and Tritium, took lots of tests.) I'm sure it won't be online by 2020 or probably 2030. But hey most large scale energy ideas aren't in full practice either and won't be for a loooooong time.

Nice if they fix the magnetic fields, but how to transfer the energy if it is ever generated. Magnetohydrodynamics was all the rage in the early 60s. Burn fossil fuels at close to 3000K to form a plasma, run the plasma between charged plates to generate electricity at close to 100% efficiency until the plasma is cool enough to run into a conventional boiler/steam turbine system. Theoretical efficiencies would be over 60%. The trouble is that no materials are available to run the 3000K end of the deal. So how will energy transfer work at 2 million K??

Quoting DrDeke (Reply 18):
However, it strikes me as slightly nuts to burn natural gas for base load utility power in most circumstances.

Just as long as you are doing the English art of understatement Dr D and mean totally nuts, that is fine by me!! Big grin
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Wed May 02, 2007 6:42 am

Question for you, Baroque:

I read today that PM John Howard has committed Oz to financial support for Gen IV reactor research. Since Oz does not have nuclear power, although the DIDO reactor at Lucas Heights is in place, does this act indicate that the government is trying to 'prepare the field' for the development of nuclear power ? As well, the article seemed to indicate he was going to call for repeal of the ban on new uranium mines.

We'd be happy to sell you a few CANDUs -- especially since Australia actually has the $$ to pay for them. With the ore deposits you have, no need for enrichment, Australia would have complete control over its' nuclear fuel cycle.

Cheers, mate.
Nostalgia isn't what it used to be.
 
Klaus
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RE: Advantages And Disadvantages Of Nuclear Energy

Wed May 02, 2007 7:04 am

Quoting DfwRevolution (Reply 2):
generation of electricity produces no carbon, nitrous, sulfuric, or mercury pollution

Incorrect.

As the declining sources for natural uranium are mined ever deeper, the extraction consumes an ever increasing amount of fossil fuels and thus produces an increasing amount of greenhouse gases and toxic pollutants. It just doesn't happen visibly at the power plant itself but instead thousands of kilometers away, often in the third world where the nuclear cheerleaders simply couldn't care less.

Add to that the obvious problems of nuclear proliferation (India / Pakistan, North Korea, Iran, anyone?) and the still unsolved viability of waste storage / processing with all its deferred and thus far completely ignored subsequent costs and it's a typical case of glossy brochures backed by a much dirtier reality.
 
galapagapop
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RE: Advantages And Disadvantages Of Nuclear Energy

Wed May 02, 2007 7:33 am

Quoting Klaus (Reply 30):
Incorrect.

As the declining sources for natural uranium are mined ever deeper, the extraction consumes an ever increasing amount of fossil fuels and thus produces an increasing amount of greenhouse gases and toxic pollutants. It just doesn't happen visibly at the power plant itself but instead thousands of kilometers away, often in the third world where the nuclear cheerleaders simply couldn't care less.

Add to that the obvious problems of nuclear proliferation (India / Pakistan, North Korea, Iran, anyone?) and the still unsolved viability of waste storage / processing with all its deferred and thus far completely ignored subsequent costs and it's a typical case of glossy brochures backed by a much dirtier reality.

True but compared to every other alternative, this is by far the most efficient and cleanest. Oil, Gas, Wind, Solar, Dams, and so forth all require oil and dirty resources to be built or explored in the first place. It's all energy in the end. Either way you split it Nuclear power is by far the most viable option until Fission or Fusion come around and even then none are the endall nor without penalties.
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Wed May 02, 2007 7:38 am

Quoting Klaus (Reply 30):
As the declining sources for natural uranium are mined ever deeper, the extraction consumes an ever increasing amount of fossil fuels and thus produces an increasing amount of greenhouse gases and toxic pollutants. It just doesn't happen visibly at the power plant itself but instead thousands of kilometers away, often in the third world where the nuclear cheerleaders simply couldn't care less.

Red herring, Klaus. All mines, whether uranium or coal, produce greenhouse gases. Oil & gas production produce greenhouse gases. Wind farm creation produces greenhouse gases. Solar cell creation produces greehouse gases (plus some other stuff you _never_ want to know about). But nuclear energy generation _at the source_ produces essentially no greenhouse gases for a very high energy density, on a per sq metre basis. Unlike wind & solar.

Quoting Klaus (Reply 30):
Add to that the obvious problems of nuclear proliferation (India / Pakistan, North Korea, Iran, anyone?) and the still unsolved viability of waste storage / processing with all its deferred and thus far completely ignored subsequent costs and it's a typical case of glossy brochures backed by a much dirtier reality.

Complete BS. Enriched fuel used in American/European/Japanese PWR reactors cannot be used for weapons, not enriched nearly enough by half. Natural uranium fuel used in CANDU reactors cannot be used for weapons as well. Nuclear electricity generation has _zero_ to do with proliferation. Unless of course you want to go to the trouble of building an industrial-scale seaparation plant, which creates its' own set of problems and red flags with the IAEA.

Now, if you want to look at proliferation schemes, get yourself a research reactor. They usually _need_ fairly well enriched fuel. And that _can_ be used for a weapon.

As for waste storage, ask the Canadians, who built a demostration storage facility back in the 80s, ask the Finns, who are building one now. Technically this is not a problem. And, in fact, and as I've stated earlier, you really want to retain the spent fuel at hand so you can re-use it. The only obstacle to actual storage is what it has always been, NIMBYs (I'm including you in this group by default) and politicians unwilling to make a decision.
Nostalgia isn't what it used to be.
 
WSOY
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RE: Advantages And Disadvantages Of Nuclear Energy

Wed May 02, 2007 7:36 pm

Quoting Klaus (Reply 30):
and the still unsolved viability of waste storage / processing with all its deferred and thus far completely ignored subsequent costs and it's a typical case of glossy brochures backed by a much dirtier reality.

As far as the Finnish situation goes, there's a pioneering research project into a final disposal storage with deposits scheduled to commence from 2020 and continue into the 2100s. The costs have been AFAIK been counted into the price of the present projects. Similar type of bedrock is found widely worldwide. esp. in the northern hemisphere.

Main characteristic of the deposited fuel:
- 96% of the spent fuel is still uranium
- the radioactivity of spent uranium fuel decreases to about a hundredth of its original level in just a year
- only a thousandth of the original radioactivity of the nuclear fuel will remain when the fuel is finally disposed of.


More:
general
video

[Edited 2007-05-02 12:48:53]
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baroque
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RE: Advantages And Disadvantages Of Nuclear Energy

Wed May 02, 2007 11:44 pm

Quoting Connies4ever (Reply 29):
We'd be happy to sell you a few CANDUs -- especially since Australia actually has the $$ to pay for them. With the ore deposits you have, no need for enrichment, Australia would have complete control over its' nuclear fuel cycle.

I think most current interest is in the thorium cycle, but getting reasonable information through the media is difficult because they don't have much of a clue (witness the number of reporters who seem to think clean coal is probably normal coal that has been dusted, or perhaps polished!!).

The Candu reactors attracted a great deal of interest back in the 60s, when a guy called Baxter was head of the Atomic Energy Commission. I suspect the enriched reactor sellers had the inside running due to greater financial power, and the whole lot lapsed probably due to costs, but there was some foundation work done down at Jervis Bay about 150km S of Sydney.

At a guess, gasification of our coals, combustion in oxygen, collection and sequestration of the CO2 will give about the same energy costs as current U reactors. The obscure ways that nuclear power station costs are done is probably one of the big drawbacks to nuclear, well apart from the scares about radioactive emissions. No notice is taken of the emissions by each and every coal burning power station of huge amounts of radioactive material. Not dangerous, mind you, but huge compared with a well run nuke power station.

It appears that the costs of the thorium cycle reactors really ARE unknown. If the theory works, they should be very attractive in terms of lower amounts of waste.

Quoting Connies4ever (Reply 32):
As for waste storage, ask the Canadians, who built a demonstration storage facility back in the 80s, ask the Finns, who are building one now. Technically this is not a problem. And, in fact, and as I've stated earlier, you really want to retain the spent fuel at hand so you can re-use it. The only obstacle to actual storage is what it has always been, NIMBYs (I'm including you in this group by default) and politicians unwilling to make a decision.

Quite so. Australian granitic cratons are especially well-suited to construction of disposal sites. Even better if they employ synrock. The nuclear industry suffers today from some sloppy work done in the past, especially some early work on disposal. But the Canadian and Finnish work looks pretty good from the little bits I know. Keeping things in granites should hardly be rocket science mind you.

I cannot even begin to think why the "bury it in salt" school of thought developed.

As a side issue, some recent profiling of what were thought to be massive granites perhaps 5 to 10 km thick, has shown that many are quite thin, perhaps 1 to 2 km, although for the most part the material underneath is sufficiently similar that it does not matter. However, it does appear that quite a bit of work needs to be done on granite masses. A late friend of mine would have been greatly excited, his research field was on some of the more obscure textures within granites, especially the myrmekite intergrowths.

The NIMBY factor looks like putting off nuclear power stations here indefinitely as it is putting off development of storage facilities. Oddly enough, native title rights might come to the rescue with storage as many of them contain granites and if a properly developed project is put to these groups, at least one might see it as a way to a prosperous existence.
 
WSOY
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 3:30 am

Quoting Baroque (Reply 34):
But the Canadian and Finnish work looks pretty good from the little bits I know. Keeping things in granites should hardly be rocket science mind you.

There's quite a bit of research going on nevertheless, see e.g. http://www.stuk.fi/julkaisut/tr/stuk-yto-tr196.pdf
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Banco
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 3:48 am

One of the issues facing the UK concerning a new generation of nuclear power stations is the question of security of supply. With North Sea oil and gas beginning to run out, Britain will become a net importer of these energy sources in the next few years. Although the UK has a good agreement with Norway, the prospect of becoming ever more reliant on Russia for gas is one the government are having nightmares about. Quite simply, they aren't prepared to countenance the idea. So, the alternatives are to re-open the coal mines and invest in clean-burning stations, or consider a new generation of nuclear stations. Renewable sources are simply not going to cover the requirements in the immediate future, so it seems almost certain that nuclear power is going to be at least a part of the solution. For all the arguments about it being a "green" source of energy, it is the fact that the UK will not be reliant on a capricious gas supplier that is at the forefront of their minds.

Incidentally, I used to work at Dungeness B nuclear power station many years ago. It's an eye opener, I can assure you.
She's as nervous as a very small nun at a penguin shoot.
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 7:17 am

Quoting WSOY (Reply 33):
As far as the Finnish situation goes, there's a pioneering research project into a final disposal storage with deposits scheduled to commence from 2020 and continue into the 2100s. The costs have been AFAIK been counted into the price of the present projects. Similar type of bedrock is found widely worldwide. esp. in the northern hemisphere.

AECL actually did the pioneering research at the URL (Underground Research Laboratory) starting about 1982.
This was a multi-partner multi-nation collaborative effort with the USA, Japan, Sweden, France, and Finland providing funding at different times over the years, as well as Ontario Hydro (now Ontario Power Generation). A shaft was sunk 440m into an essentially continguous piece of granite in the Canadian shield to test and demonstrate technologies suitable for a long-term nuclear fuel repository.

Further info and schematic here:
http://www.civil.engineering.utoront...ound_Research_Laboratory__URL_.htm

Quoting Baroque (Reply 34):
I think most current interest is in the thorium cycle, but getting reasonable information through the media is difficult because they don't have much of a clue (witness the number of reporters who seem to think clean coal is probably normal coal that has been dusted, or perhaps polished!!).


We actually burned Thorium in a research reactor back in the 1970s but never progressed to doing so in a power reactor. Th fuel produces U233 which does have some nasty daughter products, moreso than U235. But there are bucketloads of Th lying about compared to U.

Quoting Baroque (Reply 34):
The Candu reactors attracted a great deal of interest back in the 60s, when a guy called Baxter was head of the Atomic Energy Commission. I suspect the enriched reactor sellers had the inside running due to greater financial power, and the whole lot lapsed probably due to costs, but there was some foundation work done down at Jervis Bay about 150km S of Sydney.

Yeah, CANDU costs more up front, currently about CDN $1.5B for a 700 MWe unit, but fuel costs are essentially negligible since there is no enrichment component. The capital cost includes the required D2O moderator/coolant.

Quoting Baroque (Reply 34):
I cannot even begin to think why the "bury it in salt" school of thought developed.

Agreed. Seems like a massive mistake to me.

Quoting Baroque (Reply 34):
As a side issue, some recent profiling of what were thought to be massive granites perhaps 5 to 10 km thick, has shown that many are quite thin, perhaps 1 to 2 km, although for the most part the material underneath is sufficiently similar that it does not matter. However, it does appear that quite a bit of work needs to be done on granite masses. A late friend of mine would have been greatly excited, his research field was on some of the more obscure textures within granites, especially the myrmekite intergrowths.


We have what were formerly called plutons but now called batholiths shown to be 5+ km deep. In our own URL I've been down to the bottom at 440m. When they turn the lights out it's dark. Mind you, I also went to the bottom of the Creighton miine outside Sudbury during a visit to SNOLab (Sudbury Neutrino Observatory & Laboratory) -- that's just over 2 km down.

Quoting Banco (Reply 36):
One of the issues facing the UK concerning a new generation of nuclear power stations is the question of security of supply. With North Sea oil and gas beginning to run out, Britain will become a net importer of these energy sources in the next few years. Although the UK has a good agreement with Norway, the prospect of becoming ever more reliant on Russia for gas is one the government are having nightmares about. Quite simply, they aren't prepared to countenance the idea. So, the alternatives are to re-open the coal mines and invest in clean-burning stations, or consider a new generation of nuclear stations. Renewable sources are simply not going to cover the requirements in the immediate future, so it seems almost certain that nuclear power is going to be at least a part of the solution. For all the arguments about it being a "green" source of energy, it is the fact that the UK will not be reliant on a capricious gas supplier that is at the forefront of their minds.

Incidentally, I used to work at Dungeness B nuclear power station many years ago. It's an eye opener, I can assure you.

Security is important, that's for certain. And, since you worked at Dungeness, perhaps it's the devil you know ...
Nostalgia isn't what it used to be.
 
WSOY
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 9:04 am

Quoting Connies4ever (Reply 37):
AECL actually did the pioneering research at the URL (Underground Research Laboratory) starting about 1982.

Thanks for the information! I think the word "pioneering" was put into where I found it because the aim from the beginning is to deposit the fuel there as well as perform the necessary research. I don't seem to find mentions of an actual working final solution anywhere else.
www.posiva.fi seem to be spending more time drilling the rock than updating their own links, but I managed to dig up their English "final solution" presentation video, here
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northstardc4m
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 9:55 am

ok im going to play another card here.

Chernobyl and Three Mile Island both were water cooled reactors. There is another design out there that is much safer and more efficient.

Pebble Bed reactors use inert gas as coolant, helium, carbon dioxide, nitrogen... No steam transition to cause explosions. they also use solid Carbon was moderators, which unlike water reactors, stays stationary and cannot turn to gas to cause problems.

Even better, you can shut down every single safety and cooling system and walk away, the reactor will warm up to 400-500*F and stay there. 500*F is about 1000 degrees below the melting point of the graphite pebbles used in the reactor, so a meltdown is literally improbable to a point approaching infinity. Shut down the cooling system on a water reactor and you get Chernobyl... And even if the spheres DID melt, they would not be able to breach the reactor walls after there would be no explosion of water turning into steam. The coolant is already gas.

South Africa has been experimenting with Pebble Bed Reactors for some years, China has an experimental one running at 10MWs, and is building a 200MW production facility now, with plans for many more adding up to 2.5GWs by 2020. Germany (west) had a pebble bed reactor running for 22 years (1966 to 88), it was shut down in the post Chernobyl anti-nuclear political swing and because it was becoming too expensive to operate. It was a small reactor designed to turn Uranium 235 to Thorium 235, not for generating electricity economically.

Other advantages are that the reactor can run on almost any fuel type: Plutonium, Thorium, Uranium... even unenriched uranium. China plans to re manufacture fuel rods expended from water plants as pebbles for the new reactors and get many many more years of use out of them. Theoretically, the pebbles can be re manufactured dozens of times to re concentrate the radioactive elements... basically there is no highly radioactive leftovers. The eventual waste fuel would have a radioactivity close to a household smoke alarm.

So what about worst case disaster? Well ok... IF a reactor was breached and the inert gas escaped and got replaced with air, graphite in the pebbles could ignite and cause some mild radioactive fallout. Compared to a traditional reactor however, the damage would be tiny, and most likely partially reclaimable. The gas escape could spread some radioactive dust out, however this would not be a large amount and most likely would disperse so widely that no action would be required in the short term. Long term cleanup might involve having people dump out rain water and spray down of certain areas with cleasing agents/radioactive moderators (heavy water or graphite suspensions). No massive "green zone" like Chernobyl, or water table problems like Three Mile Island. And some sort of foam inerting system is part of both the Chinese and South African designs. Basically flood the reactor chamber with inert foam that can withstand the heat of the pebbles and seal out the oxygen in the air outside.

Ok, thats it, thats all, the end... thanks for reading...
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 10:03 am

Quoting WSOY (Reply 38):
Thanks for the information! I think the word "pioneering" was put into where I found it because the aim from the beginning is to deposit the fuel there as well as perform the necessary research. I don't seem to find mentions of an actual working final solution anywhere else.

Very welcome. The AECL effort was a protoype and the only reason it actually got built in Manitoba was that the provincial government put a caveat in the agreement such that NO real used fuel could be put into the lab, only inert fuel and tracer radioisotopes. Having said that, it was an experiment (or series) worth doing and a huge amount of data and opex was gleaned. Going foward, if we do build a repository, it will be successful. The Finns learned a lot, too, which made their decisiono that much easier. I still think above-ground storage in concrete/steel canisters is better/cheaper, and leaves the fuel readily available for future reprocessing.

Quoting NorthStarDC4M (Reply 39):
Pebble Bed reactors use inert gas as coolant, helium, carbon dioxide, nitrogen... No steam transition to cause explosions. they also use solid Carbon was moderators, which unlike water reactors, stays stationary and cannot turn to gas to cause problems.

Pebble beds have a lot of attractive features, potentially. No one has actually built an operational plant on an industrial scale, however. It has only been proof-of-concept. So we shall see what happens in South Africa. I wish them luck. One drawback is that the efficiency of the thing isn't up to PWR/CANDU levels, from what I've read. But that coudl change of course.
Nostalgia isn't what it used to be.
 
Banco
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 4:52 pm

Quoting Connies4ever (Reply 37):
And, since you worked at Dungeness, perhaps it's the devil you know ...

It was a hobby of some of the staff to try to think up ways of defeating the safety systems and cause a major nuclear accident. The management would be quite happy about this, because it serves a valuable purpose - if the systems can be defeated, then change them so they can't. One of the peculiarities of some of the pressure groups opposed to nuclear power is that they give the impression of laxity and don't seem to realise that the staff tend to be rather keen on making sure nothing goes wrong, given that they are working right next to it.
She's as nervous as a very small nun at a penguin shoot.
 
WSOY
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 9:07 pm

An interesting diagram: load factor ("uptime") of nuclear power stations in various countries:
(slightly dated)



source
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baroque
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 9:50 pm

Quoting WSOY (Reply 35):
Quoting Baroque (Reply 34):
But the Canadian and Finnish work looks pretty good from the little bits I know. Keeping things in granites should hardly be rocket science mind you.

There's quite a bit of research going on nevertheless, see e.g. http://www.stuk.fi/julkaisut/tr/stuk...6.pdf

Thanks to you and Connies for the links. Mind you, that one on the Finnish research would get 2/10 try again because the abstract does not tell you what it found, just what they are going to do. I cannot abide abstracts that do this. There is a famous paper on the abstract explaining what not to do in an abstract and those guys break every rule.

However, persisting to the paper, shows that you need to do serious work even on apparently massive granites.

Quoting NorthStarDC4M (Reply 39):
500*F is about 1000 degrees below the melting point of the graphite pebbles used in the reactor, so a meltdown is literally improbable to a point approaching infinity.

You are underselling graphite there NSDC4M! Graphite is still VERY solid at 3000C. Doubtful if it can be melted.

It should be relatively cheap to build structurally sound repositories, but it is good to see that serious work is being done in advance to find any problems. Quite a marked improvement over the "sink it in salt" and hope approach!!

That is a good point about the operators having a vested interest in not having the things go wrong.

Quoting Connies4ever (Reply 37):
We actually burned Thorium in a research reactor back in the 1970s but never progressed to doing so in a power reactor. Th fuel produces U233 which does have some nasty daughter products, moreso than U235. But there are bucketloads of Th lying about compared to U.

I think one of the systems would burn the U233 during the process. But I am not sure of the details of the system except that it is never critical and has to be started with a burst of neutrons. Must look out some information, but meanwhile, I need to concentrate on graphitic carbons tonight, aka met coke!!
 
TedTAce
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RE: Advantages And Disadvantages Of Nuclear Energy

Thu May 03, 2007 9:55 pm

Quoting Galapagapop (Reply 26):
Solar is not a viable option until overal consumption is reduced

I beg to differ (not to say it could be a primary source, but a viable alternative). I think the biggest osbtacle is adoption. 42" plasma TVs used to cost $15,000 now they cost around $1,500. Increased production could reduce costs if the demmand could be initiated.

As far as Hydro concerns go, we do need to re-invent the wheel. Instead of totally changing the way the river system works, find ways that leverage the existing flow and try to minimize the impact. We also need to closely monitor how the transformers are taken care of to ensure that nothing enters the river/stream.
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northstardc4m
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RE: Advantages And Disadvantages Of Nuclear Energy

Fri May 04, 2007 1:17 am

Quoting Baroque (Reply 43):
Quoting NorthStarDC4M (Reply 39):
500*F is about 1000 degrees below the melting point of the graphite pebbles used in the reactor, so a meltdown is literally improbable to a point approaching infinity.

You are underselling graphite there NSDC4M! Graphite is still VERY solid at 3000C. Doubtful if it can be melted.

It should be relatively cheap to build structurally sound repositories, but it is good to see that serious work is being done in advance to find any problems. Quite a marked improvement over the "sink it in salt" and hope approach!!

Ok the question i guess is then is it the Graphite itself that melts, or is it the other components of the pebbles that melt... All this is coming from one of the many documents the Chinese have put out recently, so its probably highly conservative.

I think the bigger problem is the graphite burning if oxygen gets in... but again the reactor vessels should be able to be designed to greatly reduce that risk.

Still, it will be interesting to see what HTR-200 can do, maybe be the beginning of real safe ecologically friendly electricity
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.
 
BarfBag
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RE: Advantages And Disadvantages Of Nuclear Energy

Fri May 04, 2007 1:54 am

Quoting Klaus (Reply 30):

Add to that the obvious problems of nuclear proliferation (India / Pakistan, North Korea, Iran, anyone?) and the still unsolved viability of waste storage / processing with all its deferred and thus far completely ignored subsequent costs and it's a typical case of glossy brochures backed by a much dirtier reality.

WTF is this nonsense about India's nuclear program amounting to proliferation ? On what basis do you presume such garbage ?
 
WSOY
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RE: Advantages And Disadvantages Of Nuclear Energy

Fri May 04, 2007 4:13 am

Quoting Baroque (Reply 43):
There's quite a bit of research going on nevertheless, see e.g. http://www.stuk.fi/julkaisut/tr/stuk...6.pdf

Thanks to you and Connies for the links. Mind you, that one on the Finnish research would get 2/10 try again because the abstract does not tell you what it found, just what they are going to do.

I think there's a reason behind the fact. The paper is, as they say, "a critical report", commissioned by the regulatory authorities from independent ingestigators with a view to finding any faults in Posiva's plans. They may even not have been expected to commit themselves to anything beyond that.
"Nukkuessa tulee nälkä" (Nipsu)
 
connies4ever
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RE: Advantages And Disadvantages Of Nuclear Energy

Fri May 04, 2007 7:28 am

Quoting BarfBag (Reply 46):
WTF is this nonsense about India's nuclear program amounting to proliferation ? On what basis do you presume such garbage ?

Yes, I think we have to give credit where credit is due on this account. India used the CIRUS research reactor (see, Klaus?) to get their first real amounts of plut for the "Golden Buddha" device in 1974. One thing that does bother people is that India has listed the TAPP station (2x220 MWe, basically clones of the Canadian Douglas Pt reactor) as a non-checkable site for IAEA purposes, which to me means that, althoguh it may churn out some electrons to the grid, it is rweally being used to produce plut.

In actual fact, I don't think too many people worry about India as a proliferation 'seed point'. It is a stable democracy with a strong constitutional tradition. If any country can manage the nuclear file, India can. I am much more worried about Pakistan. I fear there are not many controls there, and I am also quite worried about the future in that state. I can foresee onlyh problems.

The bottom line on proliferation is, any country that REALLY wants a nuke will get one. It depends obn how much you're prepared to sacrifice.
Nostalgia isn't what it used to be.
 
baroque
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RE: Advantages And Disadvantages Of Nuclear Energy

Fri May 04, 2007 10:41 pm

Quoting NorthStarDC4M (Reply 45):
Ok the question i guess is then is it the Graphite itself that melts, or is it the other components of the pebbles that melt... All this is coming from one of the many documents the Chinese have put out recently, so its probably highly conservative.

I think the bigger problem is the graphite burning if oxygen gets in... but again the reactor vessels should be able to be designed to greatly reduce that risk.

I think the trick is to have the graphite VERY pure. Other elements wreck its moderating effects. But you are right, graphite will burn quite nicely, although its ignition temperature is relatively high so you would have to have a oxygen leak AND temps toward the top of the possible range. My point was if it was just temperature, pretty much everything else around would melt before the graphite pebbles. If graphite was easy to melt, we would probably be swamped in (large) artificial diamonds!!

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