Small Nuclear Power Reactors

[Jed Rothwell]

All kinds of interesting stuff has been added to this UIC web site lately. It is impressive. Almost too impressive; I fear they might succeed and hold back the development of CF!

Main index:

http://www.uic.com.au/nip.htm

Here is a paper about thorium fuel:

http://www.uic.com.au/nip67.htm

Here is something about small nuclear power reactors, including some that we have discussed here, and some I have never heard of:

http://www.uic.com.au/nip60.htm

Here is something that sounds like a CF reactor, except it is way more dangerous. The scale and power output is similar to what I envision for a medium-sized community CF generator:

"A small-scale design developed by Toshiba Corporation in cooperation with Japan's Central Research Institute of Electric Power Industry (CRIEPI) and funded by the Japan Atomic Energy Research Institute (JAERI) is the 5 MWt, 200 kWe Rapid-L, using lithium-6 (a liquid neutron poison) as control medium. It would have 2700 fuel pins of 40-50% enriched uranium nitride with 2600°C melting point integrated into a disposable cartridge. The reactivity control system is passive, using lithium expansion modules (LEM) which give burnup compensation, partial load operation as well as negative reactivity feedback. As the reactor temperature rises, the lithium expands into the core, displacing an inert gas. Other kinds of lithium modules, also integrated into the fuel cartridge, shut down and start up the reactor. Cooling is by molten sodium, and with the LEM control system, reactor power is proportional to primary coolant flow rate. Refuelling would be every 10 years in an inert gas environment. Operation would require no skill, due to the inherent safety design features. The whole plant would be about 6.5 metres high and 2 metres diameter."

It sounds like a small diesel generator.

Or this:

"A related project is the Secure Transportable Autonomous Reactor - STAR being developed by Argonne. It a lead-cooled fast neutron modular reactor with passive safety features. Its 400 MWt. size means it can be shipped by rail and cooled by natural circulation. It uses U-transuranic nitride fuel in a cassette which is replaced every 15-20 years. The STAR-LM was conceived for power generation, the STAR-H2 is an adaptation for hydrogen production. Its reactor heat at 780°C is conveyed by a helium circuit to drive a separate thermochemical hydrogen production plant, while lower grade heat is harnessed for desalination (multi-stage flash process). Any commercial electricity generation then would be by fuel cells, from the hydrogen."

Now THAT'S what I'm talking about! 15-20 year refuelling. Multi-stage flash desalination. (This is what you need for irrigation. Other techniques leave too much salt in the water for long-term use. See chapter 8.) It is just a darn shame the thing is radioactive.

Freeman Dyson wrote that the tragedy of the nuclear power industry was that it grew too big, too quickly. Researchers should have had more time to "play around" with designs. In the 1950s, Dyson worked on one that was "inherently safe" with passive safe features. I believe that evolved into CANDU. The papers on this web site give me the impression that the fission industry developed backwards. The effusion of ideas and prototypes that we see today should have taken place before reactors were built on an industrial scale in the 1960s. The designs discussed here make existing reactors look primitive and dangerous.

Great stuff. But unfortunately many of these reactors will end up being operated by drunks & idiots, and no matter how you cut it, radioactive fuel is hazardous.

- Jed