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Small modular nuclear reactors get a reality check in new report (newatlas.com)
submitted 5 months ago by machinin to c/technology
153 comments fedilink hide all child comments
 

[T]he report's executive summary certainly gets to the heart of their findings.

"The rhetoric from small modular reactor (SMR) advocates is loud and persistent: This time will be different because the cost overruns and schedule delays that have plagued large reactor construction projects will not be repeated with the new designs," says the report. "But the few SMRs that have been built (or have been started) paint a different picture – one that looks startlingly similar to the past. Significant construction delays are still the norm and costs have continued to climb."

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[–] machinin 29 points 5 months ago (10 children)

Does anyone know about the technology that nuclear submarines and aircraft carriers use? Why are they able to operate but we can't use the same technology on land?

[–] Poayjay 57 points 5 months ago

I was a nuclear operator in the Navy. Here are the actual reasons:

  1. The designs are classified US military assets
  2. They are not refuleable
  3. They only come in 2 “sizes”: aircraft carrier and submarine
  4. They are not scaleable. You can just make a reactor 2x as big
  5. They require as much down time as up time
  6. They are outdated
  7. The military won’t let you interrupt their supply chain to make civilian reactors
  8. New designs over promise and underdeliver
  9. They are optimized for erratic operations (combat) not steady state (normal power loads)
  10. They are engineered assuming they have infinite sea water available for everything

There’s more but that’s just off the top of my head

[–] [email protected] 40 points 5 months ago (1 children)

Because if the military wants something, budgets are big. And they do not need to make money.

[–] Dasus 18 points 5 months ago (1 children)

Military expenses, the only socialism acceptable to Americans.

[–] Zron 9 points 5 months ago (2 children)

Gotta love how the post office is legally required to show they can turn a profit, but the military has a history of building literal burn pits that essentially burn US tax dollars by lighting equipment on fire and giving soldiers cancer.

[–] PriorityMotif 3 points 5 months ago (2 children)

I don't think the military should show a profit. That would just bring back colonialism. Although, they do make a hefty profit for defense contractors.

[–] Zron 6 points 5 months ago

The fact that this was your take away is concerning.

No government service should have to show a profit. If it’s an essential service, then it needs to be done. The only time money should come into it is in regular audits to ensure the budget is being used efficiently.

[–] [email protected] 2 points 5 months ago

Yup, the military's purpose is to not be needed. It should be strong enough to deter attack and assist diplomacy (carrot and stick), and no larger. Our (US) military is bigger than that, so it gets used in place of diplomacy.

[–] Dasus 3 points 5 months ago

https://www.teenvogue.com/story/most-ridiculous-things-united-states-military-spent-money-on

Boner pills, anti-rape lip balm (which they destroyed) and other such brilliant things.

And the margins for DoD contracts can be through the roof.

During her face-off with manufacturing company TransDigm at the hearing, AOC questioned the company’s alleged price gouging on a small metal part, called a “non-vehicular clutch disc,” that the government purchases for the Department of Defense.

According to the congresswoman from the Bronx, the part is about 3 inches in size and costs TransDigm $32 to produce — which is why she’s pissed the company is charging $1,443 per disc. The company reportedly sold the government 149 discs for $215,000.

[–] pelya 28 points 5 months ago (1 children)

Because military engineers overengineer these things from the most expensive materials available, and they also perform frequent maintenance on them, which is also expensive.

[–] [email protected] 20 points 5 months ago

To add to this: A certain type of Soviet submarine used a lead-bismuth alloy as coolant for their reactor. The coolant solidifies at ambient temperature so it had to be heated indefinitely by some way or another or else it solidified and trashed the reactor. I don't think any of them exist anymore since Russia wasn't able to afford sustaining the giant navy after the Soviet collapse.

Just goes to show how insane nuclear submarine engineering is, or was at some point.

[–] SlopppyEngineer 13 points 5 months ago

Why are they able to operate but we can’t use the same technology on land?

Military budgets. You can use the tech, but no civilian can afford it.

[–] [email protected] 11 points 5 months ago

I'm pretty sure they essentially are "one time use" only.

Extremely simplified:

They run for 20-30 years without refueling, which means the reactors/system could be built more compact, a higher level of safety and require less maintenance / monitoring / fine-tuning.

All those parameters are connected in an equation which means if you want higher safety you have to make another parameter "worse". By making the system "one time use" you set the "refuelability" and "repairability" parameters to the lowest and can therefore up the other parameters.

Also, military requirements are very different from civilian.

[–] [email protected] 11 points 5 months ago* (last edited 5 months ago) (1 children)

They used pressurised water reactors with enriched uranium. Dunno how the costs run but there is no strategic alternative anyway. They also wouldn't want such highly enriched uranium to be commonplace.

[–] [email protected] 3 points 5 months ago

And cost isn't really an issue for militaries, while it absolutely is for civilians.

[–] [email protected] 9 points 5 months ago

It's expensive in subs too

[–] assassinatedbyCIA 7 points 5 months ago

I’m pretty sure most military reactors use weapons grade uranium that’s enriched to mid 90%. Countries get sensitive when you start enriching uranium to the mid 90s.

[–] notapantsday 2 points 5 months ago

Because if the electricity produced on these vessels was ten times the normal price, it would still be peanuts in the grand scheme of things.