So what are your feeling about nuclear energy? I believe it is the only way for America to become totally energy independent, but this is coming from a nuclear engineer. I could go on and on why I think nuclear energy is the way to go but I want your input on the matter.

This video has is very interesting and worth watching. It's a 60 minute story on nuclear energy and I believe it is done very well. It gives a good perspective on the dangers and benefits of nuclear energy.

http://www.cbsnews.com/sections/i_video/main500251.shtml?id=2661956n

I don't usually agree with the French on many issues but their nuclear energy policy and technologies is far more advanced than any other country in the world. This video really expands on the French's nuclear policies and how America is working to adopt and advance some of these policies and technologies.

[Edited on April 9, 2007 at 10:01 PM. Reason : haha..sorry I forgot the h in the http in the link, it should work now]

4/9/2007 9:37:02 PM

until we have the means of taking care of the waste issue other than "store that shit in a mountain" I'm against going nuclear.

4/9/2007 9:39:10 PM

Reprocessing^

4/9/2007 9:48:25 PM

Yes, i admit the nuclear waste policy in America fucking sucks. Hopefully, America can start building reprocessing plants to recycle the old waste but until then the waste just gets stored on-site. Yucca Mountain isn't even open yet.

What other alternatives do we have? We obviously cannot continue to spit dangerous fumes from coal fire plants in the air. In fact for every 9000 tons of coal burned 50 lbs of Uranium and ~20 lbs? of Thorium get release into the air. Those radioactive elements and other dangerous molecules such as sulfur dioxide cannot continued to be spit in the air at the rate is has been.

You could go for wind and solar energy but both of those sources are highly unreliable. Solar energy panels are extremely inefficient and occupy lots of land for a little amount of energy. Wind energy also isn't very efficient. They also require a lot of land for a minimal amount of energy. I believe both of these energy sources are beneficial and should continued to be used, however they put out enough energy.

And there are only a limited amount of lakes you can dam up for hydroelectric energy. Hydroelectric energy is a great source of power but the power output isn't close to enough to fulfill America's huge energy demand.

4/9/2007 9:52:55 PM

unfortunately, nuclear isn't a solution on its own, either. IIRC, our supply of uranium is, at best, ~100 years, and that's at our current rate of consumption. Fusion power suffers from a similar problem.

And this is all without looking at the problem posed by waste. Reprocessing waste is not simply a matter of taking spent fuel, pushing a magic button, and sticking the end result back into our current reactors.

Ultimately, basing our energy creation on nuclear power would be just as fool-hardy as basing it on oil. We need to have a diverse set of power creating methods, and the more renewable the sources, the better.

4/9/2007 10:04:29 PM

Quote :

"Fusion power suffers from a similar problem."

i thought there were flavors of fusion that would use isotopes of hydrogen, which would be effectively limitless. i may be off on this. i dont' know much about it.

4/9/2007 10:14:06 PM

eh, I'm not up on the current research, but most of the promising fusion techniques I have read about rely on hydrogen isotopes that are not readily available to us.

4/9/2007 10:15:56 PM

^^^i agree with you on some points. We definitely need to diversify our energy sources to stretch the Uranium supply as long as possible. I've been told by many of my nuke professors that the supply was 200 years and best and could be stretched even longer with breeder reactors.

Fusion power is not even close to being commercialized (maybe 20-40 years before our first commercial fusion reactor) however I believe its potential is amazing. Researching and further developing fusion energy along with using all clean sources of energy such as nuclear, hydroelectric, solar, wind, etc. could greatly reduce the amount of shit going into the air. Also, our energy bills will be ridiculously low

^there are a few different isotopes that could work for fusion energy with tritium being the most promising. Obviously tritium is not an easy isotope to come by yet with further research we can not only find ways to use readily available isotopes for fusion but we can also develop ways to produce it through decay and other means. The energy that can be released from from such a small amount of fuel during a fusion reaction is astonishing. The problem is being able to harness the energy and being able to use it.

[Edited on April 9, 2007 at 10:25 PM. Reason : yo]

4/9/2007 10:17:11 PM

in looking up fusion stuff a little more, i stumbled across this fairly long, but compleletely readable pdf about cold fusion from last year:

http://www.newenergytimes.com/news/2006/2006ExtraordinaryEvidence.pdf

4/9/2007 10:24:50 PM

^I'm to buzzed right now to read that so I'll get back to it.

4/9/2007 10:28:15 PM

Quote :

"I'm to buzzed right now to read that so I'll get back to it."

well this explains the case of stupid in this thread

[Edited on April 9, 2007 at 10:38 PM. Reason : emphasis added

4/9/2007 10:38:15 PM

Quote :

"IIRC, our supply of uranium is, at best, ~100 years, and that's at our current rate of consumption."

but is that also at our current level of mining and searching for uranium sources? I don't know--I'm not speaking authoritatively by any means...I'm just wondering if there is tons of uranium to be had, but we haven't bothered to go after it because we haven't had a need to.

4/9/2007 10:40:12 PM

^^the stupid in this thread?

what have you contributed? This is a very important topic. Watch the link that I posted and make some comments so you can contribute something useful to this thread.

4/9/2007 11:08:57 PM

First of all I think the dangers of nuclear waste are way overblown. If we handled it carefully there could be virtually no damage to the environment. Of course if there is an accident it could get ugly. However, compare that hypothetical to the guaranteed pollution of fossil fuels.

If nuclear fission is done right it is the best option that we have for I bet another 500-1000 years. I would be sceptical of claims that we only have 100 years worth, just like we'll be out of oil in 2050 ( until we improved the drilling technologies and found out that there is way more oil out there ). The real issue with that 100 year figure has to be the implicit assumption that we can only produce power as we are now with the light water reactors. But this is very short-sighted, it is well known physics that the nuclear by products of our current reactor system still have much energy left. The question is simply how to harness it, that is a large part of why the waste is dangerous, it has much potential by virtue of its radioactivity. The reactors that harness our nuclear waste are called breeder reactors. In principle you could have a series of these linked one after the other, each recycling the other's waste. In this fashion we could significantly extend the potential lifetime of nuclear power for mankind. This is not nearly as hypothetical as many of the so-called green technologies, the physics and technologies are essentially known they just need to be implemented. Moreover, the power available from nuclear fuels is orders of magnitude beyond chemical fuels.

Btw, because of the potential national security risks I do think the government needs to monitor nukes pretty closely. In contrast there is no such need for say ethanol or other green technologies. I have no problem with research $$ going towards those, but I don't think it is good to manipulate the market through government interference.

Finally, fusion has many technical obstacles to overcome as I understand the current research. In contrast, nuclear submarines travel around for months without outside help to maintain their nuclear reactor. During that time those sailors get less radiation then you or I do up here on the surface. Anyway with current technologies, fusion can be maintained for less than a second with roughly a return of the same energy you put into it. And this is only after the combined efforts of dozens of nuclear physicists. Again to contrast, the nuclear sub can be run by folks with a Masters level education. I like the idea of fusion but it is hypothetical at the current time, so we should count on fission until that changes. Hot fusion is fairly well known physics as I understand it, basically you can see it from the graph illustrating nuclear binding energies, at the low end stuff like hydrogen can combine or fuse together to make a new nucleus with smaller binding energy, the extra energy should be harnessed in principle to make power. Here's the problem, how to get stuff to fuse together. On the sun its not to hard, you just sit back and watch gravity crush it down until fusion happens. We have to supply those forces through some sort of magnetic trap or something, and those set-ups are hard to make stable. Think of the machine that has air blowing to keep a ball floating in air, but then imagine that the air-currents are magnetic fields and the ball is a nugget of nuclear fuel(tritrium I guess, I'm sure the nuclear engineers can fill in the details). It seems that some ingenuity is needed to make fusion a viable technology. It would also have radiation problems, but not as much as the fission. Certainly fusion is worth researching.

Of course I think we should throw some more cash at high-energy particle physics, we should build a collider that makes the LHC look tiny. But that is motivated purely by my selfish desire to see what physics looks like beyond the Standard Model. I digress.

4/9/2007 11:59:48 PM

Quote :

"I would be sceptical of claims that we only have 100 years worth,"

That's assuming no increase in breeding or reprocessing and only refers to uranium. It doesn't consider things like thorium. It's the extreme end of the pessimistic estimates.

4/10/2007 2:21:08 AM

Or the amount of uranium and plutonium left in the fuel bundles when they are discharged.

4/10/2007 5:14:38 AM

From one of the other environmental threads:

Quote :

"The data in Table 11 represent estimates of carbon dioxide emissions for the electric power sector. These emissions when taken as a whole account for 40 percent of total U.S. energy-related carbon dioxide emissions; in calculating sector-specific emissions, electric power sector emissions are distributed to the end-use sectors. The electric power sector includes traditional regulated utilities, as well as independent power producers whose primary business is the generation and sale of electricity. The industrial sector and, to a much lesser extent, the commercial sector also include establishments that generate electricity; however, their primary business is not electricity generation, and so their electricity-related emissions are included in the totals for those sectors, not in the electric power sector. Preliminary estimates indicate that carbon dioxide emissions from the electric power sector increased by 2.8 percent (65.6 MMT), from 2,309.4 MMT in 2004 to 2,375.0 MMT in 2005 (Table 11)."

http://www.eia.doe.gov/oiaf/1605/ggrpt/carbon.html

In the United States, nearly 40% of all carbon dioxide emissions are the result of burning fossil fuels for electricity production. Without that 40%, the US CO2/GDP ratio would be about 0.28; contrast with the European Union ratio of about 0.27.

			US		EU
Nuclear (MW)	 	 98,145		130,267
Fossil/Other (MW)	392,580		303,956
Total (MW)		490,725		434,223

4/10/2007 7:58:15 AM

^ Yep, radiation levels around most fossil plants are much higher than around nuclear plants with the possible (but not certain) exception being Chernobyl. It's surprising when you first hear it, but it makes sense when you consider you're burning basically ore and the least flammable heaviest impurities that are most likely to settle out near your plant are also the nastiest. People also don't realize how much mercury, lead, and other toxic metals that fossil plants put out. A good article on this topic is this one:

http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html

[Edited on April 10, 2007 at 8:10 AM. Reason : ]

4/10/2007 8:09:07 AM

Found this little piece which is kind of interesting about uranium:

Quote :

"One important fact that must be understood is that, unlike the gas and oil, the cost of the uranium ore is a negligible fraction of the cost of nuclear power (with almost all of nuclear power cost being in the form of value added by domestic labor). Specifically, at today's price of ~$40/kG of uranium, the ore costs amount to only ~0.1 cents/kW-hr (i.e., only ~2-3% of nuclear’s total power cost). The ore cost could increase by a factor of 10 (to ~$400/kg) and nuclear's power cost would only increase by ~1 cent. Thus, whereas gas and oil applications are extremely sensitive to the cost of fuel, and can be rendered uneconomical by even a small increase in fuel price, nuclear power is almost immune to ore price increases. Thus, the maximum price for uranium ore, above which nuclear power would become uneconomical, is extremely high indeed."

What these paranoids always try to do is use the currently economically recoverable supply of uranium, without concern for the fact that prices rise and nuclear is still a viable option at higher prices. Obviously it doesn't affect the price much at all, but they don't take this into account. Also with the price having been low for so long until recently, there has been little reason to search for new uranium. If they know the chance to expand has been almost nonexistant and they already have enough found and mining to last for at least 50-100 years, what is the point of wasting money finding more uranium that won't get used and you can't make money on. If nuclear reactor prolifigate in the US and the rest of the world, you will see exploration explode and MANY new sources of uranium will be found.

4/10/2007 8:51:27 AM

when a coal plant fails you are out of power.

when a nuclear plant faisl you are fucked.

4/10/2007 9:11:34 AM

Does it fucking genius?

4/10/2007 9:19:11 AM

^^ [no]

4/10/2007 9:20:36 AM

The world has already had two disasters with nuclear energy. No point in tempting further. We must look towards renewable energy, not the old standbys.

4/10/2007 9:29:14 AM

what are the 2 disasters? chernoble(sp?) and what?

chernoble(sp?) is the only one i thought was considered a "disaster"

4/10/2007 9:32:05 AM

They are renewable, nutty. If and when they become uncompetitive you renew your energy supply by switching to a different source.

It is in this way that each generation manages the highest standard of living possible.

4/10/2007 9:33:28 AM

coal, oil, and nuclear are the exact opposite of renewable.

and we've had three disasters, not two.

[Edited on April 10, 2007 at 9:43 AM. Reason : .]

4/10/2007 9:42:47 AM

Not in my opinion. I don't personally care where my energy comes from, as long as it is cheap and doesn't pollute much. By this reasoning, all sources are renewable: just get another source.

We could impoverish ourselves by switching over the solar and wind energy today, or we can do it 100 years from now when it actually makes sense (here's hoping for fusion).

My energy supply is renewable, whenever I want more there will always be nuclear, solar, wind, etc available to supply it. Until then my car burns gasoline; but so what, my car will break down long before oil becomes too expensive.

4/10/2007 10:25:07 AM

Chernobyl is the only disaster that comes to mind... and that was in the USSR. So what are these other two "disasters" you are talking about?

4/10/2007 10:29:16 AM

Quote :

"when a coal plant fails you are out of power. when a nuclear plant faisl you are fucked."

You betray your ignorance. Nuclear plants are designed such that if the conditions start to get too dangerous, the fuel for the reaction will either be reduced or, in the most extreme of cases, the reaction will be killed entirely (eg the fuel rods might be magnetically suspended open, so if there's a loss of power the electromagnets will shut down and close away the rods, preventing an uncontrolled reaction). Some plants use reactions that require really stingy conditions to run, so if something goes wrong the reaction will kill itself.

At least one of the "disasters" you're talking about was the product of poor design. Chernobyl didn't have nearly all of the standard safety features built into it (presumably to skimp on the cost), and so little surprise that it went BOOM! on them. As for Three-Mile Island, I believe that there was a problem with the coolant flow. I don't know off the top of my head if that was bad design or not, but there was no disastrous release of radioactive fallout from that incident.

Nuclear power is currently our best option to go. Provided it's done right, it is really safe and environmentally sound, and can meet our energy needs. Solar and wind aren't bad alternatives, but let's face it; they're never going to fully substitute fossil fuels in terms of energy output.

[Edited on April 10, 2007 at 11:52 AM. Reason : tags]

4/10/2007 11:52:08 AM

^your right about the coolant flow thing and the whole "kill the reaction" statement. We have learned from our mistakes and have put in backup system upon backup system into every current and future nuke power plant.



Chernobyl was a huge disaster a on world scale but what few people know is that reactor design was faulty and every nuclear engineer in the world was telling the Russians to shut the plant down. Not only did Chernobyl not have a containment building (a 6 foot thick structure fo concrete and steel surrounding the reactor), but the engineers there were running the plant at dangerous levels while skipping protocal to do it. A disaster of this magnitude will never happen again. There are containment buildings on every nuke power plant in the world, and in the very very rare case of a meltdown, there will be no radiation leakage at all.

Three Mile Island was the other "disaster" that you people speak of. Yes, there was a partial meltdown however, because of the containment building, no radiation at all was released into the outside enviroment. The workers did not even receive an elivatated radiation dose. And this was in 1971! It's been 30 years since the TMI disaster and much progress has been made.

The NRC (nuclear regulatory committee) simply does not allow for error when it comes to nuclear power plants. The are the most conservative bunch of people in America, and they have all the reason to be.

So to nutsmackr...I know you have your opinion but try to look into it more. Watch the video I posted above, read about the Chernobyl/TMI disasters, and also look at other alternatives to nuke power. I think you'll see that nuke power is the best way for America to go.


[Edited on April 10, 2007 at 11:58 AM. Reason : asfd]

4/10/2007 11:55:37 AM

Why has no one mentioned next generation designs? The new designs imcorporate passive safety systems (i.e. they don't rely on an active electrical or mechanical component to function) like high head natural circulation systems that can prevent meltdowns even in a catastrophic event, like a main steam line break.

4/10/2007 2:01:10 PM

^ Umm....

Quote :

"Nuclear plants are designed such that if the conditions start to get too dangerous, the fuel for the reaction will either be reduced or, in the most extreme of cases, the reaction will be killed entirely (eg the fuel rods might be magnetically suspended open, so if there's a loss of power the electromagnets will shut down and close away the rods, preventing an uncontrolled reaction). Some plants use reactions that require really stingy conditions to run, so if something goes wrong the reaction will kill itself."

Basically, instead of having to constantly make sure the reaction doesn't run away out of control, any deviance from acceptable parameters will kill the reaction. That is what a passive safety measure is, right? In the event of a failure, the system cannot properly maintain itself and results in its own shutdown.

[Edited on April 10, 2007 at 2:08 PM. Reason : better wording]

4/10/2007 2:07:29 PM

^ Reduction of reactivity by ways of a SCRAM (cutting power to the magjacks on control rods) is an active safety and in cases where magnetically supported control rods are used (pressurized water reactors) is only enough to end rapid power excursions, but by no means is enough to completely and safely shut down the core. The three mile island core had the control rods inserted very early in the accident and most of the damage occurred hours later. Next generation reactors will be able to go from full power to COLD shutdown conditions without operator intervention and stay there for extremely long periods of time. Currently, the most common reactor type used in the united states will require some form of operator intervention within 6-12 hours.

The control blades in current BWR reactors are sufficient to fully shutdown the core without the addition of some sort of soluble neutron absorber (boric acid.) Even so, they are still considered an active safety systems and control rods/blades can become stuck. The BWR control blades can also fail to fully insert since they rely on a pressurized system to insert them UP into the core, instead of using gravity to fall into the core.

Furthermore, many next generation reactors will not use pumps to move the core coolant. They will rely on natural circulation instead and can cool themselves without relying on moving or powered (electrically or by steam pressure) components.

[Edited on April 10, 2007 at 3:55 PM. Reason : ]

4/10/2007 3:53:42 PM

nutsmackr either you are trolling just to get a reaction out of people or you are a moron.

4/10/2007 5:43:23 PM

Quote :

"The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium."

In the long run fusion, solar, wind, geothermal are all not renewable.

4/10/2007 6:19:11 PM

Quote :

"but by no means is enough to completely and safely shut down the core."

I'm not entirely sure what you mean by the core not being completely shutdown following a scram. Certainly, fully inserting the control rods is enough to completely stop the fission reaction (subcritical multiplication and the like not withstanding).

Quote :

"The three mile island core had the control rods inserted very early in the accident and most of the damage occurred hours later. [...] Currently, the most common reactor type used in the united states will require some form of operator intervention within 6-12 hours."

The damage was not the result of an ongoing fission reaction, but rather due to a failure to remove decay heat. Decay heat removal after shutdown is a problem regardless of reactor design, though, as you mentioned, things like natural circulation are much more reliable than forced circulation.

Quote :

"In the long run fusion, solar, wind, geothermal are all not renewable."

haha...long run = billions and billions and billions of years

4/10/2007 6:49:31 PM

Quote :

"I don't think it is good to manipulate the market through government interference. "

so you're all for paying for the true cost of energy?

4/10/2007 6:54:08 PM

Quote :

"what are the 2 disasters? chernoble(sp?) and what? "

chernobyl and 3 mile island ( think jersey )

4/10/2007 7:02:25 PM

how was 3-mile Island a disaster?

4/10/2007 7:11:54 PM

it wasn't, but it is referred to as one, just was answerin his question

the only "disasters" i can think of would be chernobyl, which really comes down to funding and infrastructure (their own fault) and the atom bombs (haha)

4/10/2007 7:29:24 PM

TMI is in pennsylvania. and another disaster was SL-1

4/10/2007 7:44:32 PM

what was SL-1?

4/10/2007 8:21:16 PM

SL-1 was an Army research reactor in the Idaho desert. While certainly a disaster in the sense that the reactor was destroyed and the three operators killed, it hardly qualifies as a disaster in the sense of large scale destruction, contamination, or loss of life. By 'large scale' I mean anything beyond the building itself.

It should also be emphasized that SL-1 was an experimental research reactor from the early days of nuclear power (late 50's, I believe). It was not a commercial production reactor.

4/10/2007 8:32:47 PM

My uncles worked at SL-1 before it was destroyed.

4/10/2007 8:47:54 PM

Quote :

"I'm not entirely sure what you mean by the core not being completely shutdown following a scram. Certainly, fully inserting the control rods is enough to completely stop the fission reaction (subcritical multiplication and the like not withstanding)."

Not usually; most pressurized water reactors will return to critical and come back up to about 20-30% power even with rods fully inserted. This is due to the lowered temperature of the coolant/moderator and the fact that US reactors must run under-moderated. Cooling the moderator (the water) makes it denser, increasing the total moderation. Since the core is under-moderated this causes a net increase in reactivity which can eventually cause the core to return to criticality. To reach COLD shutdown conditions the water must have boron added to it. The rods will bring the core to 0 power upon insertion, but as it cools down they end up being insufficient to keep it there. This kind of reactor, a PWR, represents about 2/3 of the operating power reactors in the US.

With Boiling Water Reactors, the control rods do provide sufficient negative reactivity to bring the system to COLD shutdown conditions. They also serve fundamentally different roles during the operation of the plant though. PWR control rods are used to control power and average temperature. BWR rods are generally fully out of the core during operation, and core-flow rates are adjusted for power maneuvering.

You're right about TMI though, the stuck open PORV didn't cause sufficient cool down to return the reactor to criticality and since much of the coolant was lost/core uncovered there was no moderator to speak of. Just looked over the time-line again. For some reason I thought the second heat up event was due to return to criticality, but it was actually because the operators tripped off the reactor coolant pumps.

[Edited on April 10, 2007 at 11:04 PM. Reason : ]

4/10/2007 10:44:55 PM

Three Mile Island:

Quote :

"Detailed studies of the radiological consequences of the accident have been conducted by the NRC, the Environmental Protection Agency, the Department of Health, Education and Welfare (now Health and Human Services), the Department of Energy, and the State of Pennsylvania. Several independent studies have also been conducted. Estimates are that the average dose to about 2 million people in the area was only about 1 millirem. To put this into context, exposure from a full set of chest x-rays is about 6 millirem. Compared to the natural radioactive background dose of about 100-125 millirem per year for the area, the collective dose to the community from the accident was very small. The maximum dose to a person at the site boundary would have been less than 100 millirem."

pretty interesting stuff
http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/3mile-isle.html

4/10/2007 10:55:34 PM

Regarding the new presidential candidates

Does anyone know their (Romney, McCain, Clinton, Obama, etc.) take on nuclear energy as an alternative solution to fossil fuels?

[Edited on April 23, 2007 at 11:24 AM. Reason : yo]

4/23/2007 11:24:33 AM

Quote :

"Nuclear power, of course, produces no carbon dioxide."

This isn't strictly true. The nuclear fuel cycle will generate CO2 emissions. Some anti-nukes argue that the CO2 emissions from the NFC are so great as to make it no better a technology than coal or gas. But this is extraordinarily inaccurate.

4/23/2007 12:43:57 PM

Has anyone managed to find an insurance company to underwrite a nuclear reactor without Congressional Exemption from Liability?

As long as no such institution exists, I do not believe nuclear is sufficiently safe to operate in a free economy.

4/23/2007 3:47:18 PM

just curious, where does the US Navy fit into this equation?? they own a lot of reactors and their waste can't really be stored "on-site" for too long. what do they do??

4/24/2007 11:39:02 PM