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General Forums => Generic Discussion => Topic started by: P-man on May 03, 2005, 05:27:05 PM

Title: Is Nuclear Energy Bad?
Post by: P-man on May 03, 2005, 05:27:05 PM
What's so dangerous about nuclear energy? People freak out when you talk about it but actually, it's not that bad. With new technology, we'll be able to secure nuclear plants to make them safer. I know there's still the problem with the radioactive waste, but hopefully soon we'll know what to do with it. I need to know how it will have long-term effects on our society and health.
Please help ASAP.
Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 03, 2005, 10:30:38 PM
Perhaps the idea of a nuclear plant meltdown is somewhat equivalent to a nuclear fission bomb explosion. Nobody wants another Hiroshima or Nagasaki plight happen in their hometown. However, people nowadays know more myth than facts about nuclear power and they need to be educated.

A typical nuclear reactor doesnt contain fissible material at supercritical level, which is required for weapon-grade use. Moreover, the amount of fissible material put inside a reactor is such that the max pressure it can create in case of meltdown is still 10X below the critical pressure the reactor is build to endure. Modern nuclear reactors are in fact so much more safer.

The problem with nuclear plants is infact inherent of the old nuclear plants, who are slowly undergoing decommissioning. Inferior design, very prolonged radioactivity damage to strucuture, out-dated emergency protocols are among the causes to why the old nuclear plants (typically phase I) needed to phase out ASAP.

It isn't bad. People needs to be re-educated. Greenpeace anti-nuclear efforts will only hamper the progress of mankind. Does Greenpeace offer any solution to power blackouts? No. Does Greenpeace offer solution to oil crisis? No. What does Greenpeace offer?
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 04, 2005, 04:42:44 PM
I agree. People need to know that nuclear energy is the best for the environment. Nuclear reactors don't emit CO2 into the air.

But we still need to know what to do with the waste! That's what's freaking people out. They think the waste is going to kill the entire world, and in a sense, they're right!

Pierre

P.S. What do you mean by fissible?
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 04, 2005, 06:02:55 PM
Actually, nuclear power results in the production of a LOT of CO2 and requires a bunch of fossil fuels.  This is the thing that a good number of people tend to forget, and it's something that I had forgotten about in the beginning.  Uranium-235 doesn't just come out of the ground in a useable form.  The uranium ore has to be extracted, purified, and then isotopically separated in order to get the % of U-235 in the samples high enough for energy production.  All of this requires a lot of energy and heat which comes from the burning of fossil fuels.  As a result, the use of nuclear power really has no 'saving' on our fossil fuel consumption.  Plus, after the reactor has served its time, the fuel needs to be reprocessed and handled properly, and once again that takes energy.  

So nuclear power isn't exactly a 'free' energy source.  It can definitely be helpful in terms of our overall energy needs, but I think the best way to make efficient use of our resources is to have a wide variety of energy sources.  In perpetually sunny areas, use solar power to help generate electricity.  Use hydropower where it's effective.  Use nuclear power in areas close to the ores and separation facilities.  Use whatever is available in the area.  There is no 'one solution'.  
Title: Re:Why is Nuclear Energy Bad?
Post by: Corvettaholic on May 04, 2005, 06:11:42 PM
Dredging up the idea of the nuclear battery again, why not use a really big battery? Just get a lot of something with a decent half-life, and make a huge factory sized battery out of it? Don't have to worry about fuel for a good 20-40 years! Just hope nobody shoots this giant battery with a rocket launcher... that would be bad.
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 04, 2005, 08:04:21 PM
Jdurg: Your statements are a bit misleading. You get more power from nuclear energy then you put in. The way you phrased it--made it sound like an equivalent to hydrogen cells.
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 04, 2005, 08:11:56 PM
No he is right about burning fossil fuels for extracting uranium from the uranium ore. I don't know much about centrifuges but a. The require alot of electricity to run. b. I think the sample is heated during the process. Look up chernobyl and you'll know why people freak. Also check out three mile island and all of the nuclear waste produced including when the facility is decommisioned some 15 or 20 years after it becomes operational.
For all its downfalls nuclear energy and all the benefits of nuclear science outway the risk. CAT scans use radiation. Radiation is used in treating cancer. Not all radiation is harmful. Radio waves are radiation. We use microwaves to cook our foods. As was previously stated it is because people are uneducated about the topic.

P.S. Mitch is right either way you get way more energy than you put it in.
Coming in the near future a mini sun on Earth hopefully.
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 04, 2005, 08:59:22 PM
Jdurg: Your statements are a bit misleading. You get more power from nuclear energy then you put in. The way you phrased it--made it sound like an equivalent to hydrogen cells.

If that were true, then the 2nd law of thermodynamics would surely be broken.  ;)  The amount of energy you get per mass of fuel is greater with nuclear power than any other source, but it does take a great deal of energy to process that nuclear fuel and make it useable in addition to keeping it safe.  I think nuclear energy is a great source of power, but only if used properly.  Sadly, the ignorant mass known as society wants nothing to do with radiation.  
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 04, 2005, 10:29:04 PM
Anyone here care to enlighten all of us on the mining of uranium? I have no idea what the process used in mining (other than digging into caves)..
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 04, 2005, 11:39:01 PM
If that were true, then the 2nd law of thermodynamics would surely be broken.  ;)    

No it wouldn't.

I would defend my position, but I'm too lazy.
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 05, 2005, 11:04:24 AM
I still have to defend my argument there Mitch.  You simply do not get more energy out of a nuclear reactor than you have to spend to get it all running effectively.  In my argument, the energy input is the combination of the energy required to mine the fuel, process the fuel, form the fuel into a useable shape, store the fuel, transport the fuel, remove the spent fuel, reprocess the spent fuel, etc. etc.  It's not like a coal plant where you dig the coal out of the ground, shove it in a furnace and watch it burn away.  There's no real processing done and the amount of security and safety guards is far less than with nuclear power.  (Remember, it costs money and energy to have the proper safety and security levels).
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 05, 2005, 11:46:02 AM
i attached a picture to illustrate the nulcear fuel cycle.

p-man: fissible material refers to material that are susceptible to nuclear fission, eg. plutonium-239.

constant-thinker: arguing that nuclear power is beneficial or not is irrelevant to its secondary uses, such as CAT scan. You can't actually transport radiation from a nuclear reactor directly for CAT scans. Neither are the radioisotopes used in generating X-rays for CAT scans are obtained from nuclear reactors. Reprocessing the spent nuclear fuel (SNF) is a very expensive and thus ineconomic process to obtain radioisotopes for CAT scans. microwaves are generated using electronic devices, not through a nuclear source.

nuclear power refers to generation of electricity using atomic energy. typically, there are few types of nuclear reactors available in the market: LWR (light water reactor, normally american), HWR (heavy water reactor, normally canadian), MAGNOX (uses CO2 as the heat transport agent, british), and the french type (that employs liquid metal, normally Na or Li, as the heat transport agent)

Jdsurg is right to point out we should examine the entire fuel cycle to determine the "green-ness" that nuclear power offers. on one hand, uranium mining generates alot of CO2 (according to Jdsurg); on the hand, nuclear reactors can operate for many years without refueling. Comparing the CO2 generated by uranium mining per MW of electrical energy generated in nuclear plants, the nuclear plant still beats conventional fossil fuel power plants. In fact, the amount of CO2 generated by fossil fuel plants during the same operation span of the nuclear plant exceeds the amount of CO2 generated in mining sufficient uranium to run the nuclear plant for that particular operational span.

Moreover, modern nuclear reactors are much more efficient than fossil fuel power plants, espeically the french and british type of nuclear reactors. Gas and liquid metal exhibit higher heat transfer coefficient, and they can operate at much higher temperature (unlike the pressurised water reactors). This means more energetic neutrons from fission are allowed to heat up the the heat transport agent, instead of being absorbed (and thus wasted) by the control rods.

it all points out that nuclear plants are not only more green, but also more efficient. however, from an engineering point of view, the operational cost must be taken in account to evaluate the economic value of the nuclear plant, unless fossil fuel is fast becoming scarce, then nuclear plants are the next power generators we can turn to, to meet mankind's demand for energy. harnessing nuclear power is inevitable.

The rising oil price in view of much-talk-about petroleum shortage will make fossil fuel plants less and less economic to run as time goes by. increased operational cost is inevitable, and this is where nuclear plants prove their capability over fossil fuel plants.

SNF reprocessing is an area that still needs alot of research breakthrough in order to convince the cynics of their short-sightedness. The current procedure for handing SNF is to let it stand for few weeks, so that all the short-life radioactive nuclei will decay, leaving the less radioactive elements present in the SNF. (if electromagnetic radiation energy can be captured and stored as a standing wave, we could extract so much more energy from the fresh SNF)
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 05, 2005, 11:54:22 AM
I still have to defend my argument there Mitch.  You simply do not get more energy out of a nuclear reactor than you have to spend to get it all running effectively.  In my argument, the energy input is the combination of the energy required to mine the fuel, process the fuel, form the fuel into a useable shape, store the fuel, transport the fuel, remove the spent fuel, reprocess the spent fuel, etc. etc.  It's not like a coal plant where you dig the coal out of the ground, shove it in a furnace and watch it burn away.  There's no real processing done and the amount of security and safety guards is far less than with nuclear power.  (Remember, it costs money and energy to have the proper safety and security levels).

Okay, I'll rephrase. The amount of energy you get from nuclear power is cheaper then the amount of energy that is used to isolate/enrich/prepare the uranium for use.  :D
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 05, 2005, 12:22:08 PM
You simply do not get more energy out of a nuclear reactor than you have to spend to get it all running effectively

are u suggesting that energy input by mining, centrifuging, making UO2 pellets exceed by what is offered by E = mc2? It sounds incredible. I cant see how energy input from physical & chemical processes will exceed the energy output by a nuclear reaction.
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 05, 2005, 12:24:56 PM
Yeah, I still agree with Geodome.
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 05, 2005, 02:06:32 PM
My reason for stating that is because even nuclear power is not 100% efficient.  Some of the energy you receive from the fission of the uranium fuel is lost as heat which is absorbed by the reactor itself and the surrounding fuel pellets.  This energy isn't going towards the heating of the coolant and subsequently the production of electricity.  Then, you have to deal with the fact that the process of fission itself isn't 100% efficient.  There are many stray neutrons which are generated that do not cause another fission event to happen.  Those neutrons are just wasted energy.  If the fission process and conversion to electricity was completely 100% efficient, then yeah, nuclear power would the be the answer to all of our problems.  Sadly it is not that efficient and as a result, the energy required to create the nuclear power is at best equal to the amount of energy (electricity) we receive from it.
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 05, 2005, 02:11:35 PM
Those neutrons are just wasted energy.

Thats actually what generates the heat. The energy released is transferred as kinetic energy to the neutrons.

Yes, nuclear energy isn't 100% effieicient. But, I highly doubt it takes the same amount of energy to generate electricity from it than you get from it. If that was the case it wouldn't be profitable. And if it is the case, as you say, it must still be financially advantagous to the owners of the power plant somehow.
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 05, 2005, 03:15:14 PM
the useful work extracted from the reactor still greatly exceeds the energy input by physical and chemical pre-reactor processes, else there is no feasibility in power-generation if the overall useful output dont exceed input. moreover, the fission process for nuclear power shouldn't be 100% efficient, else it will become a fission bomb literally.
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 05, 2005, 07:23:27 PM
Wow. I personally think that we get more out of the nuclear energy than other sources. Look at aircraft carriers and subs. They all have nuclear reactors. Some deep space satellites use nuclear reactors (all beit a different process). When you way everything together I'd say the margin between the processing and actually making power is close, but the making power comes out on top. Even if it is more to process it'll be our next alternative unless fusion reactors start working like we want them too.
Also I misread the question appaerently I guess because I was reffering to radiation in general when I was talking about CAT scans, radio waves, ect. You still need electricity for those things though.
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 06, 2005, 09:30:01 AM
But what happens when those nuclear powered machines have an accident.  Oil spills are damaging enough to the environment and difficult to clean up, but nuclear 'spills' are far worse.  Again, I'm not someone who is against nuclear power.  I think it is a great thing to make use of, but I'm also realistic and know that it's not a panacea for our energy needs.  I would use the analogy that nuclear power is like a bottle of nitroglycerine.  In the right hands and used in the right manner, it can do wonderous things.  If you aren't 100% safe and handle it improperly or without the respect it deserves, however, the resulting damages can be devastating.
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 06, 2005, 06:55:30 PM
OK, here is my share of information.
I heard from my grandfather (who studied at PhD level chemistry in university), that nuclear energy DOES NOT produce CO2. Furthermore, he defends nuclear energy as the answer to our energy problems. But one thing is still missing: what do we do with the waste? That is a question not yet answered and even my grandfather admits that it puzzles him. Now, I was extremely surprised when jdurg posted saying nuclear reactors produced "A LOT" of CO2. I'm still confused and will contact my grandfather again soon.

Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 06, 2005, 06:59:29 PM
I agree with you jdurg. That was a good point. Too bad there are people who want to cause massive destruction, and there always will be. It's a daunting task to secure nuclear materials in the world. Especially with the break up of the USSR.
Title: Why is Nuclear Energy not Bad?
Post by: Donaldson Tan on May 06, 2005, 07:06:37 PM
nuclear energy DOES NOT produce CO2.. Now, I was extremely surprised when jdurg posted saying nuclear reactors produced "A LOT" of CO2. I'm still confused and will contact my grandfather again soon.
Pierre

p-man, jdsurg meant that the mining of uranium produced alot of carbon dioxide. the nuclear reaction itself doesnt  produce carbon dioxide. look at the nuclear fuel cycle chart that i had attached above. jdsurg meant that the CO2 was produced at mining and milling stages probably compensated for lack of CO2 not produced during the nuclear reaction.

if we must examine the entire nuclear fuel cycle to determine if nuclear power is green, the same must be done for conventional fuel cycle for a proper case-to-case comparision. Although I am a chemical engineer, I am not familiar with petroleum engineering. Perhaps I will learn about it at a later time in college. I am not sure how much carbon dioxide is released during the petroleum extraction process, but I am sure the 'mining' process isn't green.

even using conventional fuel has its problem. I am sure you all remembered the Kuwait Oilfields burned for 7months during the Gulf War. The probability of such a war happening is approximately the same as a nuclear incident, so we can actually compare nuclear incident to the Kuwait Oil Fires on the same basis. The environmental effect is as bad as a nuclear incident, so discounting nuclear power by its adverse effect in case of a nuclear incident is not a sufficiently strong reason to consider nuclear energy is bad.


*i feel convicted to change the title of my post
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 08, 2005, 06:47:34 PM
OK, so if we found a way to mine and mill the uranium without producing CO2, it would be fine?
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 08, 2005, 07:07:41 PM
P-man: Define fine.

The turbines are machines and need oil to be lubricated which generates waste. Nuclear Power plants are huge industrial complexes and they will generate waste accordingly.
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 08, 2005, 07:30:37 PM
Let's just say we put all our brains together and found a way to make nuclear energy without producing CO2, find a way to deal with the waste, and, above all, make nuclear energy safe, then Earth would be a better place.

Now, that doesn't seem too hard, does it? Well, why don't we do it? That is what I will commit myself to do. I will study nuclear energy further and use my brain wisely. If we all did what I want to do, then the results would be more than spectacular. Therefore I invite you all to think with me and make Earth a better place.

Now, we need to be wise, and not think like Greenpeace or orginizations like that, who have nothing to offer instead of what we use right now. We need to come up with a replacement to what we use today. Please help me do this.

Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 08, 2005, 09:01:51 PM
I may be kinda nieve in saying this since I don't that much about fusion. In theory it sounds great. Tons of heat=tons of steam=tons of electricity. Sadly fusion can't be sustained yet without using more power than it produces. I think the future would have to be in fusion power not fission. All though electrolisis requires lots of electricity I'm sure plenty would be produced by the plans I saw for a join venture with the U.S., Japan, and a couple other countries wanting to build a 40billion dollar require. Yes expensive, but we'll learn alot if it ever happens.
Title: Re:Why is Nuclear Energy Bad?
Post by: Corvettaholic on May 09, 2005, 11:47:36 AM
About fusion...

I remember reading an article somewhere which stated that given sufficient fuel, this particular reactor produced more power than was required to get it started. Only lasted something like 10ms though. Not over-unity either, because it requires fuel.
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 09, 2005, 03:41:33 PM
O. I briefly heard about it and saw a quick thing on it. It said it'd take in 50mw and output 500mg. I wondered how the could get a sustained reaction for long periods of time. They already have fusion reactors, but it takes so much energy or the fusion can't be sustained.
Title: Re:Why is Nuclear Energy Bad?
Post by: Corvettaholic on May 09, 2005, 07:40:46 PM
Well there's a new tokamak design that is more vertical than horizontal, kind of like a beach ball. Supposed to work a lot better!
Title: Re:Why is Nuclear Energy not bad?
Post by: Donaldson Tan on May 11, 2005, 12:30:40 AM
the shortcoming of nuclear power would be waste processing. currently, there isn't a viable process to convert nuclear waste to non-toxic substance. the penetrating nature of radiation requires it to be stored very very deep underground, however there's a possibility that the nuclear waste might contaminate the watershed. nuclear power, despite its potential, is one of those technology that are delivered to the public before they are perfected. Burning Conventional fuel produces alot of sulphur dioxide and oxides of nitrogen. It is a major contribution to acid rain, which nobody has solved the problem. People still live with acid rain and global warming, what more is nuclear contamination? Firstly, the shortcomings of nuclear power is comparable to that of conventional fuel; Secondly, the high fuel efficiency and lower CO2 emmision makes it green; Thirdly, its operational cost is cheaper than conventional fuel power plants, thus making nuclear power more economic. Isn't it conclusive that nuclear power is good?
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 11, 2005, 08:20:34 AM
Yeah, but it's a lot easier to protect yourselves and your property from the effects of acid rain.  Plus, you can install scrubbers which lowers the amounts of sulfur and nitrogen oxides released into the air.  It's a bit more difficult to reduce the amount of radioactivity that spent fuel gives off, and it's a lot easier to live with acid rain than it is nuclear contamination.  I still think nuclear power has its uses, but an entire energy supply based on nuclear power is not the way to go.  (Nor is an entire energy supply based on fossil fuels).
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 11, 2005, 03:58:39 PM
You're the best, geodome!

Once we find a way to process the waste and mine and mill without producing CO2, we will probably use nuclear energy as our top energy.

Furthermore, some countries are already basically run on nuclear energy, like France, for example. France makes so much nuclear energy that it exports some of it to the UK.

Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 11, 2005, 08:21:42 PM
All the factories and power plants in the midwest produce tremendous amounts of NOx. The nitrous oxides react with an antiorganic compound that is produced naturally by trees. The reaction of the 2 forms O3 and some other things.The o so kind jetstream brings all that pollution up to New Hampshire where we have plenty of trees. I live around the trees. I have asthma and on our many high ozone  days I have a helluva time breathing. Not pleasant at all. I'd prefer the nuclear reactors over the fossil fuels any day. Just take all the nuclear waste and bury it very deep in special facilities. I know it costs alot but it's my opinion. Also the nuclear power plant in Seabrook, NH can provide almost enough power for the whole state.
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 11, 2005, 11:12:15 PM
When we "bury" nuclear waste it is not forever. The thought has always been to keep the waste in the hope that someday we can extract more power from it. As it stands the technology exists to reuse US's nuclear waste today! The problem is that its cheaper to mine more Uranium then it is to reuse the Uranium. As we run out of our Uranium stockpiles, which is a lot, there will be more financial push to begin looking at reusing the waste.
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 13, 2005, 06:27:59 PM
Well where's all the negative stuff coming from? ;)
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 13, 2005, 11:48:07 PM
environazis
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 14, 2005, 01:25:56 AM
environazis

haha..  :jump:
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 14, 2005, 08:35:14 PM
An example of environazis would be...? :alien1:
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 15, 2005, 02:01:42 PM
Well where's all the negative stuff coming from? ;)

People with a teency-weency bit of information on the subject who watch waaaaaaay too much TV/Movies and think everything they see in the media is 100% true.  Then these idiots who have no real jobs and no real lives go around spouting off their horribly inaccurate statements and getting all of the other clueless members of society to agree with them.
Title: Re:Why is Nuclear Energy Bad?
Post by: corey2 on May 15, 2005, 03:36:12 PM
Think positive !! :)
Humankind will find a way to clean nuclear wastes, and secure nuclear reactors.
Think about nuclear fusion reactors and LENR reactors, LENR waste treatment for recycling heavy and radioactive metals ! ;D
We NEED more and cheaper energy every day.
Fission nuclear reactors are only transitional.
coal and oil will die, very fast considering the always rising prices of oil in the world in the last 2 years.  
A lot of european states pay as much as 1.20 euros/litre= 5.75 $/gallon for 95 octane gasoline. :o  :(

Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 16, 2005, 06:06:04 PM
Finally something rather positive, jdurg! :)
Title: Re:Why is Nuclear Energy NOT bad?
Post by: Donaldson Tan on May 16, 2005, 08:12:07 PM
coal and oil will die, very fast considering the always rising prices of oil in the world in the last 2 years.  
A lot of european states pay as much as 1.20 euros/litre= 5.75 $/gallon for 95 octane gasoline. :o  :(

actually, only 20% of the oil reserves are available to mine/drill. the other 80% are inaccessible by our current technology plus mining some of these oil reserves will destroy people's home. What would you do if u discover that the entire New York City itself is resting on a giant oil reservoir? The cost to move and rehabiliate all the economic infrastructure and people of new york city will be astronomical.

the idea of using nuclear waste as recycled fuel is wonderful but there isn't any technology available to do it ecomomically. meanwhile, we must support all our nuclear research instead of protesting against them. it will only lead to buracreatic pressure to reduce funding on nuclear research and less people to study nuclear energy technology. In 1997, the American Nuclear Society (ANS) did a survey to find only 500++ american undergraduates pursueing nuclear engineering. Lack of new blood to replace the retiring scientists/engineers and reduced funding leads to reduced effort (lesser manpower and money) in nuclear research. It is a worrying issue for all global citizens.
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 16, 2005, 08:35:31 PM
So being a healthcare provider, computer technician, or a nuclear physicist are are going to be some in demand jobs. Either way we will need a new form of power. Especially for hydrogen cars. Indirectly they produce pollution because it requires a lot of electricity. Most of our power is produced from fossil fuels, namely coal. Good news about oil is you can extract some from coal not an overwhelming amount but a considerable amount according to my a physics teacher I had when I took Physical Science.
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 17, 2005, 05:01:22 PM
I believe we actually DO have the technology to reuse the nuclear waste.

Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 17, 2005, 08:19:01 PM
I believe we actually DO have the technology to reuse the nuclear waste.

Pierre

Define reuse. :P
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 17, 2005, 08:20:24 PM
Wasn't it stated we have the technology, but it isn't economical. Meaning it is to expensive to be put to practical uses currently. Until we find a better cheaper way the waste will just sit there and decay.
Title: Re:Why is Nuclear Energy Bad?
Post by: Mitch on May 17, 2005, 08:30:03 PM
good, someone actually reads all the posts. ;)
Title: Re:Why is Nuclear Energy Bad?
Post by: billnotgatez on May 18, 2005, 06:24:25 AM
This quote came up at the bottom of this tread randomly

"I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." - Albert Einstein

I wonder what Albert would think of fission nuclear power plants. Surely his thoughts would have more intellectual weight than GWB and his cronies.
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 18, 2005, 05:03:38 PM
I thought GWB (George W Bush) is some codename for a chemical nerve agent until i realise it's the big man himself. Haha.. GB is the codename for Sarin.
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 19, 2005, 04:15:39 PM
The point is that we have the technology to do it. It's just more expensive than just mining new uranium.

Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: jdurg on May 20, 2005, 11:12:21 AM
I thought GWB (George W Bush) is some codename for a chemical nerve agent until i realise it's the big man himself. Haha.. GB is the codename for Sarin.

Well, GWB does cause stupidity the more you are exposed to it, and numerous other adverse events such as heart attacks, high blood pressure, and uncontrolled retardation have been associated with expsoure to GWB.   ;) ;D
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on May 20, 2005, 02:22:06 PM
This should be included in the MSDS sheet for the White House  ;D
Title: Re:Why is Nuclear Energy Bad?
Post by: flinguist on May 20, 2005, 11:09:26 PM
Nuclear power is a good alternative to fossil fuels. The main problem right now is what to do with the spent fuel. This article has some interesting perspectives that are more realistic than what the general public has been fed by the media. http://www.nuc.berkeley.edu/thyd/ne161/ncabreza/sources.html
Title: Re:Why is Nuclear Energy Bad?
Post by: constant thinker on May 21, 2005, 08:56:39 PM
I see you haven't read all of the posts.
Title: Re:Why is Nuclear Energy Bad?
Post by: P-man on May 24, 2005, 05:38:11 PM
It's a good article anyways. I'll use it for my project on Nuclear Energy.

Pierre
Title: Re:Why is Nuclear Energy Bad?
Post by: Mr. Pink on June 30, 2005, 03:14:57 AM
Not all radiation is harmful. Radio waves are radiation. We use microwaves to cook our foods. As was previously stated it is because people are uneducated about the topic.
Well, that would be true, but I'm pretty sure they're referring to ionizing radiation (gamma rays, alpha particles, beta particles) and not radation on the red side of the spectrum.
Title: Re:Why is Nuclear Energy Bad?
Post by: Mr. Pink on June 30, 2005, 03:16:29 AM
Well, GWB does cause stupidity the more you are exposed to it, and numerous other adverse events such as heart attacks, high blood pressure, and uncontrolled retardation have been associated with expsoure to GWB.   ;) ;D

Not to mention a relaible amount of ignorance, and a severe tendancy to jackassism.
Title: surprise surprise surprise
Post by: Donaldson Tan on July 24, 2005, 07:56:26 PM
Clean Nuclear Energy? A German Dr. Rudolf Schulten solved the problem in the 1950s. He invented the Pebble Bed Reactor (PBR). However, his research program was closed down by the German Government after Chernobyl due to political reasons.

it's called Pebble Bed because the fuel elements used are called pebbles. it uses an inert gas (helium) to act as the heat transfer agent. the helium gets heated up inside the reactor, which in turn runs a low pressure turbine to generate power. Helium has a low neutron cross-section, so it hardly gets radioactive despite exposure to the fuel elements. This allows the helium to directly power the generators instead of using heat exchangers (eg. sodium loop in fastbreeder reactors and heat exchangers in light-water reactors). This minimises the overall energy loss.

LWR has steam explosion point. This places an operational temperature limit on LWR. Helium, being a noble gas, has no explosion point. It can operate safely under high temperature. The high temperatures also let the turbine to extract mroe mechanical energy from the same amount of thermal energy. In another words, the pebble bed reactor uses less fuel per kilowatt-hour.

As the reactor gets hotter, the rate of neutron capture by U-238 increases, reducing the number of neutrons available to cause fission. This places a natural limit on the power produced by the reactor. In fact, the reactor is designed such that the cooling rate exceeds the heat generation rate. Even if the neutron moderators are removed, the idle temperature remains low. the case of a meltdown is thus very very unlikely.

Some designs of the pebble bed reactor allow it to be throttled by temperature, ie. by controlling the flow of helium, the energy generation can be increased or decreased, if the need arises. In another words, control rods are not necessary to moderate the reactor. Still then, it uses carbon rods as moderators (for maintenance sake).

PBRs are intentionally operated above the annealing temperature of graphite, so that Wigner energy is not accumulated. This solves a problem discovered in a famous accident, the Windscale fire. One of the reactors at the Windscale site in England (not a PBR) caught fire because of the release of energy stored as crystalline dislocations (Wigner energy) in the graphite. The dislocations are caused by neutron passage through the graphite. At Windscale, a program of regular annealing was put in place to release accumulated Wigner energy, but since the effect was not anticipated during the construction of the reactor, the process could not be reliably controlled and led to a fire.

 
Title: Re:Why is Nuclear Energy Bad?
Post by: Donaldson Tan on July 24, 2005, 08:38:58 PM
one more thing to add is the pebbled design of the fuel element allows radioactive waste to be self-contained. the fuel element (fissible material) is enclosed within a hollow pebble inside 15000 "seeds". Breaking the fuel element nto pebbles, and pebbles into seeds assures that the maximum release by a cascade of containment failures will be small. The pebble enclosement consist of layers of pyrolytic carbon and silicon carbide.

The layer of porous pyrolytic graphite right next to the fuel element absorbs the radioactive gases (mostly xenon) emitted when the heavy elements split. Most reaction products remain metals, and reoxidize. The gaseous fission products remain in the reactor to contribute their energy.

The low density layer of graphite is surrounded by a higher-density nonporous layer of pyrolytic graphite. This is another mechanical containment. The outer layer of each seed is surrounded by silicon carbide. The silicon carbide is nonporous, mechanically strong and fire-proof.

This allows the spent pebbles to be disposed as pebbles without additional chemical reprocessing. At the same time, the radioactivity level of the spent pebbles are minimised to meet criteria for safe disposal.
Title: Re: Is Nuclear Energy Bad?
Post by: arlojeffrey on April 15, 2009, 08:06:36 PM
Nuclear Facts

Energy:  Approximately 200 MeV of energy is released in a fission reaction.  Compared to breaking a carbon bond such as burning coal, releases 4 eV of energy.  Therefore, much less uranium or other fissile fuel is needed to create the same amount of energy.   Additionally, in the LWR used in the U.S. typically 97% of the energy released in a fission reaction is carried away in the form of heat by the water coolant.  Overall the electric efficiency of nuclear plants is about 33%.

Because of high energy density there is relatively little waster.  The entire spent nuclear fuel from this country that has been built up over the last 40 or so years by 100 or so plants that produce about 20% of this country's electricity is 56,000 tons.  This country consumes just over 1 billion tons in coal each year.  Like mining anything, heavy machinery and electricity are needed to do the job.  However, the simple fact is if it wasn't economical it wouldn't be done.  Additionally, not that much uranium actually needs to be mined compared to coal.  What's more is that the pebble bed reactor and other potential Generation IV reactors that are gas cooled will provide process heat applications.  One very important role is using that heat to create hydrogen.  Therefore, if you have non-CO2 electricity production, and heavy machinery running on hydrogen, the mining, enriching, and fabrication, and even reprocessing would have even less of a carbon footprint.  It can be found all over the web, that on a per unit of electrical energy basis, Nuclear energy has the lowest greenhouse emission cycle with the exception of hydroelectric.  Although still very low compared to coal, gas, and oil, both solar and wind power require much more construction than nuclear plants for the same amount of energy and in turn have slightly more CO2 release in the cycle.

I have a Master's in nuclear engineering.  I realize that nuclear power is not perfect. Nor is any other energy source and implementation perfect.  Like most people, I would love the day when all our energy can be clean, renewable and cheap.  However, all forms have their virtues and vices.  Solar  currently cannot compete economically with the mainstream sources of energy and like wind suffers from the inability to produce power much more than 20% of the time (Wind can be as high as 40%).  Compared to nuclear which produces 90% of the time out of year.  It doesn't shut down at night.  It works when the air is still.  Nuclear's vice is not radiation release.  Coal plants release far more radiation than nuclear plants do.  More people die each year from mining coal and oil than died from the accident at Chernobyl.  The problem isn't long term storage of nuclear waste.  1.7 billion years ago natural conditions underground in Oklo, Africa prompted a series of fission reactions that produced plutonium.  Scientific studies have shown that for 1.7 billion years these products moved 10 feet or less.  So storing even without reprocessing can be done safely.

The vice of nuclear energy is that it instills fear in those who are not informed.

Nuclear may not be answer 500 years from now.  However, fossil fuels can no longer be a solution if we want to have an unpolluted earth 500 years from now.  Solar and Wind are great sources of power, but in the near future, they cannot by themselves meet the energy demands of the world.  Nuclear does provide the answer now.

Please continue to post questions on this page.  I will do my best to check this site on a weekly basis and answer any questions.
Title: Re: Is Nuclear Energy Bad?
Post by: Borek on April 16, 2009, 03:07:04 AM
wind power require much more construction than nuclear plants for the same amount of energy and in turn have slightly more CO2 release in the cycle.

From what I have read there is an unexpected problem with wind power, that makes its use even more problematic.

Electric system of an area must be able to deliver correct amount of energy any time, in response to the needs. As wind power is not reliable (in terms of its dependency on the weather) it needs some backup systems. So far thest solution we can offer are classic heat power stations, bases on coal/gas/oil whatever. However, wind can stop to blow in minutes, and heat power stations need many hours before they can start generate electricity. To keep them responsive they have to be ready, they have to be running idle. When running idle they generate CO2 without electricity - which means that overall balance is worse (or at least not better) than in the system without wind turbines.

I think it was in some Danish report on the effect of the wind farms on their electricity generation.
Title: Re: Is Nuclear Energy Bad?
Post by: doc30 on December 09, 2009, 02:21:50 PM
arlojeffrey, very good reply. I cannot beleive people think nuclear power is a net carbon producer when nothing could be farther from the truth. Then again, there are people who think the moon landings were fake, people rode dinosaurs like horses and magnetic bracelets cure arthritis.