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by technicalbard 1278 days ago
The very first nuclear reactor went from idea to operating in 2 years. In the middle of WW2.

The only reason nuclear projects take longer than other industrial projects is regulatory capture.

4 comments

The wartime Hanford reactors did not produce any electricity. They had no safety containment systems. And they released cooling water containing radioactive contamination directly into the Columbia River:

https://www.osti.gov/opennet/manhattan-project-history/Proce...

Aside from "possible catastrophes" involving control rod failures, enemy bombing, or sabotage, DuPont's greatest concerns about reactor operations involved pumping Columbia River water through the reactors for cooling purposes. Using a "once-through" system, water was taken from the river and chemically treated before passing through the core of the reactor at the rate of 75,000 gallons per minute and being released back into the river. The reactor used canned fuel slugs, which prevented radioactive fuel from getting into the coolant as long as the cans did not accidentally rupture. Even if no fuel escaped, however, there was induced radioactivity of the impurities and treatment chemicals within the water. Radioactivity thus inevitably entered the Columbia. To alleviate possible dangers, DuPont engineers diverted the heated and "somewhat radioactive" exit water, containing mostly, but not exclusively, short-lived radionuclides, as well as certain chemical contaminants, to a 12,000,000 gallon retention basin. Each basin was divided in two, with the two sides operating in parallel. Monitoring for radioactivity occurred at the inlet to the basin, at an intermediate point, and at the exit. After six hours, radioactivity diminished by a factor of about twenty. With radioactivity below the then tolerance dose for complete immersion, the water was further diluted with wastewater free from radioactivity and returned via underground pipes for release in mid-river.

During WW2 the US could build a ship in 39 days. Now it takes 10 years.
I know this point is made a lot but I’m not sure it’s that meaningful.

WW2 boats were not the enormously complex network and sensor systems that today’s are. While, yeah, 10 years is extreme, but I don’t think 39 days is physically possible.

The 39 day boats built in WW2 were probably more similar in complexity to a modern boat than a WW2 reactor is to a modern reactor.
It was Liberty ships—slow, high-capacity, not especially durable cargo ships built as fast as possible, assembly-line style. The median construction time only got that low after the assembly line really got going and they were able to work out some kinks. It was over 200 days early on.

Warships—none of the capitals ships, certainly—weren't built that fast. Not even the cheap-as-hell escort carriers we built tons and tons of, I don't think. Destroyers and little corvettes and other smalls screen and utility ships, maybe some of those weren't too far from 39-day construction times.

I would be surprised if some of the systems were actually harder to work on back then. Old battleships always seemed to have insane amounts of wiring and cabling, because they used the nightmarish one signal per wire protocol in the pre digital age.
> because they used the nightmarish one signal per wire protocol in the pre digital age.

Can you say more about this? I find that kind of thing fascinating.

https://softsolder.com/2017/11/05/battleship-wiring/

They presumably used to have to run an individual wire for every. single. signal, or at most, they'd have extremely simple multiplexing.

I have no idea what these cables do, but I'm glad I'm not the one repairing it. Not only is there physically a lot of wire, 90% of it looks to be going directly to something mechanical.

I don't know how modern ships do it, but with civilian digital logic , you'd probably run a few redundant ethernet(Or fiber, or CAN) links to some kind of fan out box right near the switches or motors.

Cars these days are very extreme about it, sometimes even running the entertainment system commands over the fairly critical CAN bus for some reason.

If one of those cables went bad, spanning tree protocol would save you till you fix it, and probably tell you which cable broke and maybe even where. Mix them up, no problem, firmware knows what to do.

Plus, everything goes through a computer, so you've got logging and all kinds of stuff to help spot issues, rather than the classic "Oh well, noise and intermittent connections, we live with it till it gets bad enough to be all the time".

The only rats nest is right from the mechanical switch to your PLCish thing, but that's short enough to trace by eye.

You might have zero concern about interference in cables, because they might be fiber.

You won't have complicated color code schemes or wiring diagrams, or cut off wires that nobody knows where they go to anymore, you can just test it, because you don't have 50 thousand things to sift through.

People argue about whether digital or analog is more reliable, but digital is definitely easier from a hardware perspective, the hard stuff is done in factories by robots.

I'm sure the technicians had special training and it was a lot better than average civilian industrial uses of the pile o wires system, but I would think it would still be time consuming and not paralellizable, only so many people can fit around one of those giant bundles at once.

I could also be vastly misinterpreting how modern ships are wired, I know some industrial setups today insist on home run wiring instead of condensing to digital.

And you think the safety record of those ships was the same as today?
A hell of a lot safer than a WW2 reactor!
Well, and that the nuclear reactors back then commonly had terrible accidents and after Chernobyl (and TMI in a lessor manner) we realized that you can really screw up the planet with a nuclear oopsie whoopsie.
The planet? No, you can’t.
Or because covering half of Europe to the level that in some places you, even to this day, have to measure the radiation levels of mushroom and wild game is irrelevant?

https://www.researchgate.net/figure/Distribution-of-radiatio...