Is a Decades/Centuries-Long Fission Reactor Possible?

[nuclear]

hi guys,

I am just wondering is it possible in reality to construct a fission reactor that will operate for decades or even centuries without refueling? Theoretically, we can do so if the macroscopic absorption cross section for the fertile nuclide equals that for the fissile species. and few possible combinations are as follows:


1) Fissile= U-233 Fertile= Th-232
2) Fissile= U-235 Fertile= U-234
3) Fissile= Pu-239 Fertile= U-238

is this achievable in the reality?

 

[speso72]

If your goal is to create a power source that will last for several hundred years without needing fuel (one that fuels itself), may I suggest the following:

A very small amount of Uranium (even depeleted uranium), constantly emits radiation. Some of that radiation is in the form of low powered RF energy (the rest you can shield). If you induce the rf energy to charge a capacitor, and have it drive a bridge rectifier, the output would be DC.

Granted, yes, the overall power outputed as DC would be very low, however, if you build several thousand of these miniture 'toys', and then connected them together as if they were batteries, the total outputed DC power would then be the sum of the whole. If enough of these 'toys' are used and connected together in some neat complex circuit, then power levels as high as several mega watts can be achieved. A constant supply of power that would outlive the shelf life of its components. Great for satillites, and has very little waste, unlike reactors.

Hope this helps.

 

[Nice coder]

Americium generates alpha particles (and is easy to come by)
Alpha particles ionises gasses,
Fill a container with americium and hydrogen,
separate the protons and electrons (magnets?)
use the static electricity generated to power something (americium's half-life is about 100 years)
You can use whatever your alpha-particle producing isotope instead of americium.

Disclamer;
I may or may not be truthful
I may or may not know what i am talking about
I may or may not be correct
This disclamer is subject to this disclamer.

 

[lost_boy]

I think if you mean with perfect reactor the long distance of constantly power production (thermal energy) and not the environmental pollution, then you can find it in nature.

In Oklo (Gabun - Africa) there was 2x10^9 years ago a natural reactor with controlled reaction over five-thousend years.
It has had in the beginning a concentration of 3% U-235 which is enough to start a controlled reaction. The moderator was normal H2O. The core had a dimension of several kilometers.

The thermal pollution of this reactor went only 40 m in the ground. The radioactive waste is stored in the reactor since that time.

So it is a perfect reactor if you put enough material in it for working over a long time.

I don't believe that you can copy it to solve our energy problems. But mother Earth shows us a possibility.

LB