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Author Topic: What is the smallest possible nuclear reactor?  (Read 64846 times)

Offline SeanB

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What is the smallest possible nuclear reactor?
« Reply #25 on: 26/08/2011 21:48:18 »
Mars rovers use a few small nuclear heaters ( around 1W AFAIK) to keep essential parts warm, and of course the longest running probes use them as well, Voyager is still working, though power levels are rather much lower than when it was launched over 30 years ago. Pioneer is probably still running, though the signals are too weak to be received back on earth.
 

Offline CliffordK

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What is the smallest possible nuclear reactor?
« Reply #26 on: 28/08/2011 08:43:23 »
An RTG is a "valid" nuclear reactor in that it performs work.  And, while it may not have a fission reaction, all nuclear reactors are generating and harnessing heat.

However.

What about a Tritium Exit sign?
Radium Watch Dial?
 

Offline sophktt

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Re: What is the smallest possible nuclear reactor?
« Reply #27 on: 13/12/2013 09:28:39 »
I'm wondering just how small a nuclear reactor can be? Is it possible that in the future we could power our laptops and other mobile devices with our own mini nuclear reactors? Maybe also our homes and cars?

Roy P

Bilibino Nuclear power plant in the Chukotka Autonomous Okrug, Russia, houses the world's smallest commercial nuclear reactor. This is also featured in an energy industry site. Here is the newbielink:http://www.power-technology.com/features/featurethe-worlds-smallest-nuclear-reactors-4144463/ [nonactive]
 

Offline RD

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Re: What is the smallest possible nuclear reactor?
« Reply #28 on: 13/12/2013 13:22:33 »
 

Offline wolfekeeper

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Re: What is the smallest possible nuclear reactor?
« Reply #29 on: 23/12/2013 18:47:35 »
I think to be a reactor it has to be critical mass (RTGs are not reactors) and not blow itself to pieces (nukes are not nuclear reactors).

Minimum critical mass that Wikipedia knows about is Californium 252, at just 7 cm across, 2.7 kg, and that's without a tamper; a tamper can reduce the size.

https://en.wikipedia.org/wiki/Critical_mass
« Last Edit: 23/12/2013 18:49:06 by wolfekeeper »
 

Offline SeanB

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Re: What is the smallest possible nuclear reactor?
« Reply #30 on: 24/12/2013 17:23:18 »
The Mars rovers ( all of them) use small 1W, 5W thermoelectric heaters to keep parts warm. those are basically small apple sized units with a thick corrosion resistant housing, which provides both shielding and protection. All in all they each have as much nuclear material in them as a ton of coal.
 

Offline alancalverd

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Re: What is the smallest possible nuclear reactor?
« Reply #31 on: 25/12/2013 00:41:00 »
A "bare reactor" http://en.wikipedia.org/wiki/Godiva_device is about the size of a football but of little use as a controllable source of heat. There is market interest for dustbin-size reactors of a few megawatts: anything smaller would not meet the criteria of criticality and controllability.

Shielding need not be a problem if the beast can be located some way from human occupancy. There have been proposals for remote-controlled nuclear submarine tugs towing cargo barges but the engineering complexity of such a system makes it uneconomic compared with a conventional on-board reactor since weight is not a limiting factor in sea transport. A bare-reactor powered aircraft is feasible but presents problems of ground handling. It is difficult to incorporate a reactor with adequate shielding in a standard width road vehicle but several designs have been proposed for a nuke in a shipping container: fine for use as a mobile power source but not as a prime mover for road transport itself as it could only tow one more container on normal roads. The "nuke in a box" could however be an excellent replacement for steam and diesel locomotives, which require much less investment in track infrastructure than electric trains.
 

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Re: What is the smallest possible nuclear reactor?
« Reply #31 on: 25/12/2013 00:41:00 »

 

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