Fission is the process of nuclear power generation in which uranium, plutonium or a similar fuel is split into smaller atoms. The products are radiation ( ), heat ( ) and a bunder of smaller atoms which slowly give off more radiation in future ( ). Fission is what we already have and use, I suspect the question meant "when will fusion be a reality"
Fusion is a process in which the fuel is fused into larger atoms. The products are radiation ( ), heat ( ) and a bunder of larger atoms which do not produce radiation in future.
The problem is that while fission takes place at temperatures of a few thousand degrees and we can control it, fusion takes place at temperatures of a few million degrees - so its a bit harder to build something to hold it in!
Cheers NL and JB, that helps very much. Told you I didn't know much about this lark
Me too.
Northern_Lad
Joined: 13 Dec 2004 Posts: 14210 Location: Somewhere
Posted: Tue Jul 05, 05 11:55 am Post subject:
The odd thing this is, both methods result in the same outcome (energy), but go about it in oposite ways: fussion builds things up; fission breaks them down. It's all down to the stability of atoms. In essense, all matter wants to turn into iron.
Small atoms have a great desire, for want of a better term, to get some more friends together.
Large atoms think things are a bit too crowded and some bits should get lost.
In both methods, the change results in energy being released as things become more stable.
At present, it is by no means cut and dry that fusion will ever be a viable means of producing much of our electricity; the massive temperatures needed are something of a constraint. Fission, however, is easier to do, but requires a finite resource; uranium does not exist so plentifully that it will never run out.
bagpuss
Joined: 09 Dec 2004 Posts: 10507 Location: cambridge
Posted: Tue Jul 05, 05 12:35 pm Post subject:
but with fast breeder reactors and the like the lifetime of our nuclear fuel sources far outstrips the lifetime of the fossil fuels and argubly it will definiately last long enough for us to make the leap to technology like fusion
Personally I think nuclear power used along side renewable sources should be considered a viable possible but it shouldn't be considered the only solution
The comments with regard the radition in coal I think are misplaced though. carbon 14 maybe found at higher level due to lack of containment but the risk is presents in terms of toxicity and radiation is relatively low compared to uranium and its decay products which are quite toxic and radioactive
The radiation given off by waste is a different matter to whether living next to coal or nuclear powerstations is more dangerous. Nuclear power as we now know it is uniquely problematic in terms of how dangerous and long lasting certain waste products are; that is, I think, the strongest argument against using nuclear fusion for generating electricity. I still think that nuclear has a place.
The comments with regard the radition in coal I think are misplaced though. carbon 14 maybe found at higher level due to lack of containment but the risk is presents in terms of toxicity and radiation is relatively low compared to uranium and its decay products which are quite toxic and radioactive
Except that it is much easier to contain uranium waste and its decay products. By their nature of being heavy metals they tend not to escape whereas carbon wants to merge into your body. If the waste from a nuclear power station were not contained it would be a major problem but as it is coal liberates more radiation into the environment than nuclear power (and that's in addition to all the other pollutants!). People don't notice it from coal because it is a small fraction of the overall pollutants and dispersed so widely.
bagpuss
Joined: 09 Dec 2004 Posts: 10507 Location: cambridge
Posted: Tue Jul 05, 05 12:53 pm Post subject:
Certainly the waste produced by nuclear fuel is a huge problem and one which needs an adquate solution before more reactors are built. One of the most dangerous reactor products is plutonium which is high toxic before you even consider the radiation it emits
also did you mean fission there given if I recal the waste from fusion should be water? at least from the fusion process itself
Northern_Lad
Joined: 13 Dec 2004 Posts: 14210 Location: Somewhere
Posted: Tue Jul 05, 05 1:01 pm Post subject:
bagpuss wrote:
...if I recal the waste from fusion should be water? at least from the fusion process itself
The waste could be water, but at the moment it's far more likely to be helium. The bigger the atoms you weld together, the harder it is, so it's being done with deuterium (an isotope of hydrogen: two neutrons and a proton) and adding a proton (helium = 2p+2n). In theory, you could end up with water (2 hydrogen + 1 oxygen), but it'd be darn tricky in practice.
bagpuss
Joined: 09 Dec 2004 Posts: 10507 Location: cambridge
Posted: Tue Jul 05, 05 1:12 pm Post subject:
JB wrote:
Except that it is much easier to contain uranium waste and its decay products. By their nature of being heavy metals they tend not to escape whereas carbon wants to merge into your body. If the waste from a nuclear power station were not contained it would be a major problem but as it is coal liberates more radiation into the environment than nuclear power (and that's in addition to all the other pollutants!). People don't notice it from coal because it is a small fraction of the overall pollutants and dispersed so widely.
I actually don't think that is true. the nuclear waste produced by fission contains probably proportional numbers of alpha and beta emitters. The other downside is for uranium it takes far more decays to reach a stable product but in carbon 14 lose one electron via beta decay and it is stable and that is without taking in consideration the toxicity of nuclear waste aside from its radioactivity
My point was that if you are considering the danger of the radiation from nuclear waster or even just fuel then using the fact that proportionally coal releases more radition then it as a indicator that it is safer is a little meaningless as while the numbers do show that coal releases more beta radition through carbon 14-13 emissions taking that fact on its own is slightly meaningless.
bagpuss
Joined: 09 Dec 2004 Posts: 10507 Location: cambridge
Posted: Tue Jul 05, 05 1:14 pm Post subject:
Northern_Lad wrote:
The waste could be water, but at the moment it's far more likely to be helium. The bigger the atoms you weld together, the harder it is, so it's being done with deuterium (an isotope of hydrogen: two neutrons and a proton) and adding a proton (helium = 2p+2n). In theory, you could end up with water (2 hydrogen + 1 oxygen), but it'd be darn tricky in practice.
that will be good though as we are running out of helium as its escape velocity is less than our gravity or something like that
, mixed my names up in my second post)
), heat ( 
) and a bunder of smaller atoms which slowly give off more radiation in future ( 
). Fission is what we already have and use, I suspect the question meant "when will fusion be a reality"
View Latest Posts