nuclear fusion and fission - problems?

[gib65]

I hope I'm posting this in the right section.

 

This was inspired by this other thread, but I think it needs to be its own thread since the course that other thread seems to be going is away from my question.

 

What are the current problems surrounding nuclear fusion and fission as alternate energy sources?

 

From what I understand (and I forget how I understand this), fission is messy as it leaves a lot of toxic waste behind. The problem with fusion, as I understand it (which, again, isn't saying much) is that there's no practically efficient technology to implement it. How true are these assumptions and how promising does road to solutions look? What other problems are there?

[ydoaPs]

fission as alternate energy sources?

The fission industry is about to explode(pardon the pun). All of the current reactors in the US are about to be replaced with generation IV reactors. They like us NAVY guys, so, I'm almost guaranteed to have job offers in 5 years when my time is up.

[timo]

The physics section might have been appropriate but the thread fits in here fine, too - I think. What you said seems basically correct but I´ll reiterate it and add a few points, anyways:

 

The problem with fusion technology basically is that we don´t have it - at least not in the sense that we could obtain energy with fusion. There is also some amount of radiation involved in fusion but I cannot judge to what extend it is a relevant problem.

 

For fission, there is 2-3 main problems:

- Radiative waste: It´s not really that it is so much of it but rather that the stuff remains (measurably) radioactive for a very, very long time. Afaik, there is no real solution to the question what to do with the waste. Our currently-best idea is to dump it in special tunnels under earth which is a temporary solution for perhaps the next 1000 years.

- Devasting effects of accidents: If a coal power plant burns down then you should possibly go on holliday for a few days if you´re living close by. If you get a serious accident in a nuclear power plant, then you can get something like Tschernobyl.

- A less fundamental yet, for some people, the most convincing problem: Security and cost-efficiency. Nowadays, everyone is afraid of bearded people coming from the sky (except on christmas). Due to the severe effects of accidents on nuclear power plants, they need a high level of protection/security. This costs money which reduces the cost-effectiveness of fission-produced energy. I am not sure if that´s really a big issue as soon as you look at the numbers but it´s been mentioned in debates about whether to stop relying on fission power at all or not.

[CPL.Luke]

^ the problems with nuclear meltdowns have largely been averted wiby modern reactors. For instance china's new pebble bed reactors can be run without a cooling system and not melt down

[gib65]

Radiative waste: It´s not really that it is so much of it but rather that the stuff remains (measurably) radioactive for a very, very long time. Afaik, there is no real solution to the question what to do with the waste. Our currently-best idea is to dump it in special tunnels under earth which is a temporary solution for perhaps the next 1000 years.

 

Why can't radioactive waste be launched into space? Yes, it would probably cost a lot of money and require tons of energy, but if nuclear fission supposedly creates so much energy to begin with, why not use some of that and sell some of that?

[Klaynos]

Why can't radioactive waste be launched into space? Yes, it would probably cost a lot of money and require tons of energy, but if nuclear fission supposedly creates so much energy to begin with, why not use some of that and sell some of that?

 

It create energy in the wrong form and is very wasteful to transform it, and what happens if one of the carriers explodes on launch?

[ydoaPs]

- Devasting effects of accidents: If a coal power plant burns down then you should possibly go on holliday for a few days if you´re living close by. If you get a serious accident in a nuclear power plant, then you can get something like Tschernobyl.

It's not a problem if you know what you're doing. The US Navy has had zero nuclear power accidents of any kind ever(they remind us every chance they get).

[insane_alien]

chernobyl was a combination of bad design and stupid operators who removed a bunch of safety measures in order to carry out a test. then, they moved the control rods the wrong way and made the reactor unstable. if they left the safety measures in place it wouldn't have went kaboom.

[timo]

If everything goes right, then nothing goes wrong.

[gib65]

It create energy in the wrong form and is very wasteful to transform it, and what happens if one of the carriers explodes on launch?

 

What does it mean to say that it's wasteful to transform? Does this mean it creates waste or that it's not worth it?

 

Also, the risk of explosion upon launch is only a danger if there are people or other life near by. But what if it was done in a relatively uninhabited area like a desert or the center of Antartica. If there is life that we're worried about in these regions, couldn't we seal the area off by some means and use it for the sole purpose of launching?

[timo]

It shouldn´t be too hard to find some data and make a rough calculation on the efficiency, gib.

[Klaynos]

What does it mean to say that it's wasteful to transform? Does this mean it creates waste or that it's not worth it?

 

Also, the risk of explosion upon launch is only a danger if there are people or other life near by. But what if it was done in a relatively uninhabited area like a desert or the center of Antartica. If there is life that we're worried about in these regions, couldn't we seal the area off by some means and use it for the sole purpose of launching?

 

Wasteful as in efficiency of converting electricity into rocket fuel.

 

My point was more exploding in the lower atmosphere, fall out travels a long way.

 

And finding suitable launch sites is not as easy as you'd think... As you'd like them to be near the equator, good weather, secure etc etc etc.... and you've got to get the waste to them of course.

[swansont]

It's not a problem if you know what you're doing. The US Navy has had zero nuclear power accidents of any kind ever(they remind us every chance they get).

 

Depends on what constitutes an accident. Not everybody agrees with that claim.

 

http://www.prop1.org/2000/accident/1989/8907a1.htm

 

http://oc.itgo.com/kitsap/nuclear/clymer.htm

 

It should be noted that many groups consider any accident involving a nuclear ship or sub to be a nuclear accident (e.g. the Thresher and Scorpion are considered to be nuclear accidents by some), and what the navy considers a nuclear power accident may not include discharge of radioactive material or coolant, like incidents involving the Guardfish, Swordfish, Theodore Roosevelt or the Nimitz.

[Styrge]

Fission and fusion share the same fundamental problem: neutron flux inevitably increases the background radiation level. This tendency takes place locally and globally and can't continue at the present rate much longer without affecting the biosphere in some catastrophical way.

[npts2020]

Fission and fusion share the same fundamental problem: neutron flux inevitably increases the background radiation level. This tendency takes place locally and globally and can't continue at the present rate much longer without affecting the biosphere in some catastrophical way.

 

If you are going to oppose nuclear power, you should learn a little about the subject. Fission (particularly thermal neutron, the most common type) reactors and fusion reactors are very different machines in both operation and radiation hazards produced. The point at which they become similar is after water is heated to produce steam for turning a turbine to produce electricity.

[swansont]

Fission and fusion share the same fundamental problem: neutron flux inevitably increases the background radiation level. This tendency takes place locally and globally and can't continue at the present rate much longer without affecting the biosphere in some catastrophical way.

 

Show me data and calculations to support this.