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Are size and efficiency the most pressing issues to solve in nuclear power? I don't know a thing about nuclear issues but from the layperson's perspective, it

Are size and efficiency the most pressing issues to solve in nuclear power? I don't know a thing about nuclear issues but from the layperson's perspective, it seems like security is the biggest problem that keeps nuclear power from being used everywhere. These containers are essentially dirty bombs without detonators and must be protected as such. This might work for the military, where you could secure one on a restricted section of a FOB, but how would this work for a small town in Alaska, as the article suggests? Securing the site is only half of the problem, too. You also have to secure the supply chain for the nuclear material, as well as the disposal. The cost of disposal is another challenge. Imagine the difficulties of transporting the spent fuel from the Alaskan village. These guys have a big challenge ahead of them but it would be quite awesome if they can pull it off. Prime power generation and the supply chain issues that its fuel entails is a huge and extremely expensive problem for the military. If you could safely build this in a CONEX, that would be impressive.

ahaefner 12y ago
Commercial power reactors are very expensive initially (multiple billions). This is a huge barrier to entry for most power plants. So the thinking is if the size can be reduced so can the cost. The military is interesting because they already have small reactors in submarines and ships. And they have access to the highest grade fuel because they don't have to follow power plant regulations. So it seems like if these modular reactors would be useful to them, they could easily adapt these reactors for land use. This startup is hard to gauge because there's so few actual details about their design. For example, how are they going to use thorium as a fuel? You can't just use thorium without a strong neutron starter source or some other fuel engineering.
- jddw 12y ago
  The concept is to start small to overcome cost and regulatory barriers more quickly and for less. And yes, we kick start using thorium with low enriched uranium or spent fuel to build up U233. Then we just keep reusing the thorium fuel over multiple refueling periods without reprocessing or separations until it is depleted.
- beefman 12y ago
  'It can burn any fuel' is just code for 'we have no real core design yet'. But it doesn't matter, because no nuclear fuel is significantly better than any other, and they're all thousands of times better than alternatives. Thorium is always used in mixed cores. An accelerator-driven thorium reactor will contain uranium from breeding even if no uranium is ever loaded into it.
  - jddw 12y ago
    There are core designs for low enriched uranium loading, mixed thorium loading, and spent fuel loadings. Have to make sure a fuel design works before it's claimed to work.
    - beefman 12y ago
      With 12 years of burnup? I've been having trouble getting burnup codes to handle thorium. What are you using? Apparently I should be using Serpent. But anyway, 12 years is too long, even if it's feasible. Something like 4 years should be better, due to the learning curve on these. For instance, think of a reactor in the field as a ship on a long trip while technology at home continues to improve http://en.wikipedia.org/wiki/Wait_Calculation http://en.wikipedia.org/wiki/Wait_Calculation Edit: The lower the enrichment, and the lower the excess reactivity, the better.
ekianjo 12y ago
> essentially dirty bombs without detonators and must be protected as such. No, it's completely wrong. That's not how a nuclear plant works. And as you can see, a nuclear plant does not "explode" when it goes amok. The chain reaction is very tightly controlled and there are multiples redundancies in case things don't work as expected.
- rdl 12y ago
  "dirty bomb" is a radiological weapon, not a fission/fusion weapon, and is exactly what detonating explosives (or H gas, or whatever) inside a commercial power reactor or RTG would be.
  - jjoonathan 12y ago
    Except that a dirty bomb is designed to maximize the hazardous effects of such an event while a reactor is designed to minimize the hazardous effects of such an event.
    - justincormack 12y ago
      No, a dirty bomb is mainly designed to maximize fear, not hazard. Once its gone off, telling people it was safe is probably not going to work very well.
- damian2000 12y ago
  Except you just have to look at Fukushima to see that things can still go badly wrong, resulting in a meltdown of 3 reactors. And this happened in arguably one of the most tightly regulated and technologically advanced countries in the world.
  - Turing_Machine 12y ago
    1) Massive earthquake, followed by 2) Tsunami, followed by, 3) Complete loss of power to all control systems, followed by, 4) Gas explosions and core meltdown. Pretty much the worst possible scenario, and yet no member of the general public was killed from radiation exposure. Just how safe do you want something to be?
djb_hackernews 12y ago
I may be naive, but are there really bad actors lurking the world that a) have the resource to pull off such a crime, b) be able to get away with c) not already have means to get what ever it is they want? To take a stab at your hypothetical situation, the small town in Alaska has multiple armed guards 24/7 as well as centralized offsite monitoring. Protocols in place to alert local authorities which have protocols in place to alert state authorities, etc. The overhead will be covered by excess efficiencies in adopting such a system.
- jddw 12y ago
  Exactly right. Reactors are not attractive targets and this is very robust.
  - XorNot 12y ago
    More importantly, 9/11 hit the WTC. When it did everyone immediately said "imagine if they'd hit a nuclear reactor". But they didn't. They could've, but they didn't (and it also wouldn't have done very much damage). The reality is that even at the largest conceivable scales, nuclear security as implemented is not threatened by violent terrorism or direct action, so much as leaky side-channels (scientists selling off isotopes on the side).

ahaefner 12y ago

Commercial power reactors are very expensive initially (multiple billions). This is a huge barrier to entry for most power plants. So the thinking is if the size can be reduced so can the cost. The military is interesting because they already have small reactors in submarines and ships. And they have access to the highest grade fuel because they don't have to follow power plant regulations. So it seems like if these modular reactors would be useful to them, they could easily adapt these reactors for land use. This startup is hard to gauge because there's so few actual details about their design. For example, how are they going to use thorium as a fuel? You can't just use thorium without a strong neutron starter source or some other fuel engineering.

jddw 12y ago
The concept is to start small to overcome cost and regulatory barriers more quickly and for less. And yes, we kick start using thorium with low enriched uranium or spent fuel to build up U233. Then we just keep reusing the thorium fuel over multiple refueling periods without reprocessing or separations until it is depleted.
beefman 12y ago
'It can burn any fuel' is just code for 'we have no real core design yet'. But it doesn't matter, because no nuclear fuel is significantly better than any other, and they're all thousands of times better than alternatives. Thorium is always used in mixed cores. An accelerator-driven thorium reactor will contain uranium from breeding even if no uranium is ever loaded into it.
- jddw 12y ago
  There are core designs for low enriched uranium loading, mixed thorium loading, and spent fuel loadings. Have to make sure a fuel design works before it's claimed to work.
  - beefman 12y ago
    With 12 years of burnup? I've been having trouble getting burnup codes to handle thorium. What are you using? Apparently I should be using Serpent. But anyway, 12 years is too long, even if it's feasible. Something like 4 years should be better, due to the learning curve on these. For instance, think of a reactor in the field as a ship on a long trip while technology at home continues to improve http://en.wikipedia.org/wiki/Wait_Calculation http://en.wikipedia.org/wiki/Wait_Calculation Edit: The lower the enrichment, and the lower the excess reactivity, the better.

ekianjo 12y ago

> essentially dirty bombs without detonators and must be protected as such. No, it's completely wrong. That's not how a nuclear plant works. And as you can see, a nuclear plant does not "explode" when it goes amok. The chain reaction is very tightly controlled and there are multiples redundancies in case things don't work as expected.

rdl 12y ago
"dirty bomb" is a radiological weapon, not a fission/fusion weapon, and is exactly what detonating explosives (or H gas, or whatever) inside a commercial power reactor or RTG would be.
- jjoonathan 12y ago
  Except that a dirty bomb is designed to maximize the hazardous effects of such an event while a reactor is designed to minimize the hazardous effects of such an event.
  - justincormack 12y ago
    No, a dirty bomb is mainly designed to maximize fear, not hazard. Once its gone off, telling people it was safe is probably not going to work very well.
damian2000 12y ago
Except you just have to look at Fukushima to see that things can still go badly wrong, resulting in a meltdown of 3 reactors. And this happened in arguably one of the most tightly regulated and technologically advanced countries in the world.
- Turing_Machine 12y ago
  1) Massive earthquake, followed by 2) Tsunami, followed by, 3) Complete loss of power to all control systems, followed by, 4) Gas explosions and core meltdown. Pretty much the worst possible scenario, and yet no member of the general public was killed from radiation exposure. Just how safe do you want something to be?

djb_hackernews 12y ago

I may be naive, but are there really bad actors lurking the world that a) have the resource to pull off such a crime, b) be able to get away with c) not already have means to get what ever it is they want? To take a stab at your hypothetical situation, the small town in Alaska has multiple armed guards 24/7 as well as centralized offsite monitoring. Protocols in place to alert local authorities which have protocols in place to alert state authorities, etc. The overhead will be covered by excess efficiencies in adopting such a system.

jddw 12y ago
Exactly right. Reactors are not attractive targets and this is very robust.
- XorNot 12y ago
  More importantly, 9/11 hit the WTC. When it did everyone immediately said "imagine if they'd hit a nuclear reactor". But they didn't. They could've, but they didn't (and it also wouldn't have done very much damage). The reality is that even at the largest conceivable scales, nuclear security as implemented is not threatened by violent terrorism or direct action, so much as leaky side-channels (scientists selling off isotopes on the side).