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Post by speedy on Apr 27, 2012 1:55:42 GMT 9.5
One thing I've been wondering about SMRs, especially when used for off-grid applications, is how small can they be before the economics become too poor? 100kW(e)? 1MW(e)? 10MW(e)?
I realize that there is no hard limit, and that different reactor types will have different minimums.
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Post by Jagdish on Apr 27, 2012 3:28:16 GMT 9.5
Nuclear power plants are steam power plants with the nuclear reactor as the source of heat. It will be best to keep the size of plant the same for standardization of maintenance.
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Post by Anon on Apr 28, 2012 0:01:06 GMT 9.5
Hard to say, with 242mAm you could go very small indeed (but good luck making that stuff cheaply, if we can figure out how to make the stuff it'll probably be reserved for fission fragment rocketry). Of course there's also the question of how expensive you can tolerate, you'd pay higher price in a remote location (thus expensive hydrocarbon fuels) with no reliable renewable resources than you would in a place with a stream with decent head or where diesel fuel is relatively cheap. Atomic Insights has some good information on historical ones tried by the US military. ML-1 was designed for 300 kWe (even though it never reached that) so clearly someone thought a reactor of that power output could be useful. SNAP-10A was 500 We from 30 kWt. You could also in theory just run a reactor at reduced capacity and refuel it less often. Jagdish:- You could also have nuclear gas turbines and space nuclear reactors have used thermoelectric (SNAP-10A) and thermionic (what powered the soviet RORSATs).
- Using that logic you'd argue that we should keep the size of cars the same and that everyone should be driving around in an SUV. There's a reason Toyota sells the Yaris as well as the Land Cruiser.
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Post by Luke Weston on Apr 28, 2012 17:54:02 GMT 9.5
There are certainly some examples of very small fission power reactors that have been used in spacecraft and naval applications.
But obviously in those applications economics isn't really a strong deciding factor relative to engineering requirements for volume and mass and the like.
It is accepted that the costs can be, and are, significantly higher per unit of energy output in those demanding technical applications.
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Post by speedy on May 1, 2012 1:56:01 GMT 9.5
There are certainly some examples of very small fission power reactors that have been used in spacecraft and naval applications. But obviously in those applications economics isn't really a strong deciding factor relative to engineering requirements for volume and mass and the like. It is accepted that the costs can be, and are, significantly higher per unit of energy output in those demanding technical applications. Totally agreed. Regarding standardization, small nuclear reactors will probably never have the variety that diesel generators have, but there should still be room for several different sizes. For remote applications I'd imagine designs with a long burnup (10-20 years), where the whole unit is sent back to the factory for refueling and refurbishment if possible would be best. Since the fuel cost is a relatively small part of the total for nuclear, sacrificing some efficiency for simplicity might be worthwhile. |
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Post by Luke Weston on May 2, 2012 14:12:42 GMT 9.5
Regarding standardization, small nuclear reactors will probably never have the variety that diesel generators have, but there should still be room for several different sizes. For remote applications I'd imagine designs with a long burnup (10-20 years), where the whole unit is sent back to the factory for refueling and refurbishment if possible would be best. Since the fuel cost is a relatively small part of the total for nuclear, sacrificing some efficiency for simplicity might be worthwhile. That sounds extremely similar to the existing designs for things like the Toshiba 4S  |
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