Science Buddies: "Ask an Expert"

I'm currently researching on nuclear fission and how it is used to make energy. Before I resume my work, I'd like to know whether this technology has a bright future, keeping in mind the dangers and risks associated with it. Is this a good field to go further into, if my goal is to learn about energy sources that are currently getting a lot of attention?
I've also heard about generating power through the use of nuclear fusion. Does fusion have more a more optimistic future than fission, or are they both commonly regarded as unreliable?

You have posed a very broad question. Generally speaking we “experts” can be most useful answering narrower, project-focused questions. I do have a few thoughts about what you ask, but bear in mind that I am not an expert in nuclear power or international policy.

In my opinion fission power has a cloudy future. In addition to the long standing issues of the disposal of radioactive by-products and, even worse, the eventual disposal of obsolete nuclear power plants, the recent disasters in Japan have made the future use of fission power problematic. The United States has not built a new fission plant for decades (although according to the current Wikipedia entry one new plant has had it’s license approved by the NRC), while Germany and Spain have committed themselves to decommissioning their existing plants. Other nations have decided not to build any nuclear plants. China, on the other hand, sees nuclear power as a way to assure their national security and plans to build numerous, modern plants that are supposed to be safer than the present generation. Safety, in my opinion, has never been the most important issue — despite spectacular accidents nuclear power is relatively safe compared to fossil-fuel power plants. The problem is really how to deal with all of the radioactive materials created by such plants, materials that must be safely sequestered from the environment for very long times compared to the capabilities of our current engineering practices. My guess is that nuclear plants are here to stay, at least in some countries, but they will not be likely to be a growth industry in the United States and Europe.

Fusion power remains only a hope; commercial plants are several decades away, at best. However fusion plants share the same problem of waste disposal as fission plants, even if they may be safer in operation since runaway reactions are probably impossible in a fusion reactor.

The best career opportunities in nuclear power may lie in research and development of improved methods of nuclear waste disposal.

Again, I emphasize that this is just my, not very well informed opinion. Read the Wikipedia article and follow up on the numerous references to form your own opinions, which very probably will disagree with mine to at least some degree.

Good luck with your research.

Great to see that you're into different types of energy! Certainly you've chosen an excellent field for your interests. Thinking about alternative sources is imperative, as you never know what we'll have twenty, fifty, even a hundred years down the road. I am no nuclear physicist, so I can't really provide you with an opinion about which source is better, but I would like to lay down some facts (and questions for you to think about) to help you with your research.

You probably already know this, but fusion (putting together a couple of atoms, in simplest terms) happens with the sun, whereas "natural" fission (the splitting of an atom, if you will) is rather uncommon. Fusion generally is more powerful than fission, which, in turn, is much more powerful than mere chemical reactions. What you're looking at are sources of super-energy that are possible to achieve because I personally like to think that with science, anything could happen! So I wouldn't exactly agree with the claim that they're unreliable, but maybe more knowledgeable experts will weigh in.

In the meanwhile, here's a site that elucidates the many differences between fusion and fission: http://www.diffen.com/difference/Nuclea ... ear_Fusion. It also delves into the cost, effects, and conditions required for each. I'm sure you already know a great deal, but take a look as you might run across something you didn't see before.

Hope your research goes well,
RM

Nuclear fission reactors are generating lots of electrical power today. While the science aspects of fission are not a hot topic for research, the is a significant need for nuclear engineers to deal with the existing reactors in terms of improving efficiency and finding ways to recycle the fission materials to reduce the need to store an ever increasing amount of nuclear waste safely for thousands of years.

People have been researching ways to attempt to contain/control fusion reactions for years in so that energy can be transformed into a useful form. There have been many minor breakthroughs but so far solving one problem has lead to the discovery of additional problems.

Lots of good discussion. As said, there is tons of research being done to make fusion power a commercial reality. A good article on the state of fusion reactors can be found here:
http://news.nationalgeographic.com/news ... s-science/
A correction to one of the posts above, fusion doesn't create the radioactive byproducts like a fission reactor does, unless it uses a fission reaction to initiative fussion. However, with the application of high power pulsed lasers, this is getting less problematic.

On a side note, "power beaming" is an exciting field of research, which entails placing power sources in orbit and transmitting that power, wireless, to the ground...many, many years away, but ideal for the undeveloped regions of the world.

Good luck,
theborg

theborg wrote: ...A correction to one of the posts above, fusion doesn't create the radioactive byproducts like a fission reactor does, unless it uses a fission reaction to initiative fussion [sic]...
theborg

Fusion reactors generate very high neutron fluxes; these cause the reaction vessels to become highly radioactive. Also, the fuel cycle is likely to use tritium rather than plain hydrogen -- tritium is radioactive. It produces beta-radiation (high energy electrons) which have low penetrating power; alas tritium forms heavy water and becomes incorporated directly within living tissues where the beta-radiation becomes very damaging, hence the tritium must be sequestered just as for the case of the radioactive fuels and byproducts of fission reactors. No free lunch, I'm afraid.

The economics of solar power satellites are a severe problem. My guess: we will need a space elevator to enable such a system. Of course if we had that, we might well move into space ourselves, removing the need for power satellites completely. But that's getting off topic.