4 ms·

In this particular case, what is this quote supposed to imply?

deleted 4y ago
[deleted]
eganist 4y ago
> In this particular case, what is this quote supposed to imply? I don't know that it's supposed to imply anything but rather shine a light on the different acceptance criteria for a study reactor v. one that generates power for, in his case, mission critical needs (though power for homes and businesses would be life-critical, so it's up there). If a study reactor breaks, even though there's a possible risk to life depending on how it fails, you can endure the downtime for a bit while bringing it back up. If a practical reactor breaks, people are far more likely to die.
- likeabbas 4y ago
  That's why it's important to have a multitude of energy sources on a competitive power grid. The nice thing about SMRs is you can build enough of them to make the overall output consistent as needed, even with a higher tolerance for failure of any individual reactor.
  - moloch-hai 4y ago
    A higher tolerance for random failure, but extreme exposure to expensive repairs for systematic failure. Anything $M you have to fix in N of them costs Nx$M.
- sandworm101 4y ago
  A study reactor is also designed to break. It is meant to be easily opened up and examined after a fault. It is meant to validate the core process but also explore edge case situations. So it needs to fail gracefully. That is a more complex beast than any final product.
idontwantthis 4y ago
That small, modular, cheap reactors have been promised many times for decades and have never panned out.
- docandrew 4y ago
  We use them in nuclear submarines and aircraft carriers, so the tech seems feasible - not sure why commercial use for small reactors is such a difficult stretch.
  - rippercushions 4y ago
    Nuclear submarines cost on the order of $6B a pop, so I'd hesitate to describe anything about them as "cheap". We use nuclear reactors in them because there's no other power source that's as compact and self-contained.
    - phone8675309 4y ago
      Plus worst case for a nuclear submarine is that you flood the reactor with sea water if you have a loss of cooling.
      - sebcat 4y ago
        Surely there are worse cases for a sub than this?
        nine_k 4y ago
        The idea is that you are not going to have a meltdown even in a badly malfunctioning reactor.
        thaumasiotes 4y ago
        Is it? It's not at all difficult to stock enough seawater to flood a terrestrial plant. What's distinguishing the submarine?
nashashmi 4y ago
It is not built yet. So it is theoretical. ... And Academic.
- credit_guy 4y ago
  In that case Rickover's observations don't apply at all: (1) It is simple -> nobody said NuScale's reactor is simple. It took NRC about 6 years to approve it, and in the process NuScale had to produce about half a million pages of documentation (2) It is small -> not really. It is smaller than full size reactors, but then it delivers only 50 MW, not 1GW. Per unit of electricity delivered, it is most likely somewhat larger than a full size nuclear power plant (3) It is cheap -> relative to what? it's not that cheap. If anything, see the comments in this thread, it appears to be expensive (4) It is light -> this does not apply here. Rickover was concerned with submarines, where weight was important. This is not a reactor designed for submarines. I don't know how light it is, but nobody cares about this (5) It can be built very quickly -> well, if the first one is supposed to get online in 2029, that does not seem to be very quick, does it? (6) It is very flexible in purpose (’omnibus reactor’) -> NuScale's reactor is designed to generate electricity. That's it. What is flexibility in purpose? (7) Very little development is required -> NuScale has already worked for one decade on this. It will take until the end of this decade to see one come online. Nobody claimed "very little development is required" It will use mostly off-the-shelf components -> not really. NuScale will use a Korean manufacturer that is accredited by NRC to manufacture componenets for nuclear reactors. There's nothing off-the-shelf about this. (8) The reactor is in the study phase. It is not being built now. -> it depends what "being built now" means. NuScale can't start building before it has all the approvals. It is working on getting these approvals, if this counts as "being built now", then it's being built now. More to the point. Rickover was talking about a completely different context. People venturing cheap ideas, while he needed concrete reactors for his submarines. We are in a different world. NRC is extraordinarily stringent. The fact that NuScale got their approval is a phenomenal achievement. This should not be dismissed with the same tired old quote from Rickover that gets posted on HN almost every time we talk about nuclear reactors.
  - nextaccountic 4y ago
gonzo41 4y ago
Reality is harder than fiction. And people are bad at maintaining pipes.
jacquesm 4y ago
I'll answer that with another quote: "In theory there is no difference between theory and practice, in practice there is."
- credit_guy 4y ago
  Why the flippant quote?
  - jacquesm 4y ago
    It's not flippant at all. It is the essence of the much longer version and the real lesson contained therein, you asked a question and I answered it. If you see it as flippant then that might reflect on you. Your other comment further down in this thread is flippant, even though it is a much longer one: you reject out of hand what is contained within these words without taking the time to ponder how they do apply to the matter at hand.
    - credit_guy 4y ago
      > If you see it as flippant then that might reflect on you. It does reflect on me. It reflects the fact that I can't read minds. You gave a widely known quote, and in your mind it was crystal clear what you meant. But to other people, who can't read your mind, it just sound flippant. It sounds like you think NuScale is a bunch of theoreticians. And that with your remark you are trying to put down their decade-long quest to achieve something. Maybe it does not sound flippant to you, but I assure you, it is flippant.
      - jacquesm 4y ago
        The message, to expand on it is that they are in the earlier stages of their development and the safe bet is that by the time it is all said and done things will be much more in line with what we've come to expect from the nuclear industry, including any and all of the statements already in line with that today. So by the time it is done it will be more expensive, likely heavier, likely way late, more complex and narrower in its possible range of applications. It's not a law, it is an observation made over many nuclear deployments and to the best of my knowledge there isn't a single project that was an exception so I expect it to be true this time around as well. Which is why you can safely ignore any of the touted advantages until the product is ready to be fielded in quantity. Assuming it ever will be fielded in quantity, plenty of designs were slated for large numbers of deployment and ended up being one-offs or at best single digit runs because of unforeseen issues with the design.

deleted 4y ago

[deleted]

> In this particular case, what is this quote supposed to imply? I don't know that it's supposed to imply anything but rather shine a light on the different acceptance criteria for a study reactor v. one that generates power for, in his case, mission critical needs (though power for homes and businesses would be life-critical, so it's up there). If a study reactor breaks, even though there's a possible risk to life depending on how it fails, you can endure the downtime for a bit while bringing it back up. If a practical reactor breaks, people are far more likely to die.

likeabbas 4y ago
That's why it's important to have a multitude of energy sources on a competitive power grid. The nice thing about SMRs is you can build enough of them to make the overall output consistent as needed, even with a higher tolerance for failure of any individual reactor.
- moloch-hai 4y ago
  A higher tolerance for random failure, but extreme exposure to expensive repairs for systematic failure. Anything $M you have to fix in N of them costs Nx$M.
sandworm101 4y ago
A study reactor is also designed to break. It is meant to be easily opened up and examined after a fault. It is meant to validate the core process but also explore edge case situations. So it needs to fail gracefully. That is a more complex beast than any final product.

idontwantthis 4y ago

That small, modular, cheap reactors have been promised many times for decades and have never panned out.

docandrew 4y ago
We use them in nuclear submarines and aircraft carriers, so the tech seems feasible - not sure why commercial use for small reactors is such a difficult stretch.
- rippercushions 4y ago
  Nuclear submarines cost on the order of $6B a pop, so I'd hesitate to describe anything about them as "cheap". We use nuclear reactors in them because there's no other power source that's as compact and self-contained.
  - phone8675309 4y ago
    Plus worst case for a nuclear submarine is that you flood the reactor with sea water if you have a loss of cooling.
    - sebcat 4y ago
      Surely there are worse cases for a sub than this?
      - nine_k 4y ago
        The idea is that you are not going to have a meltdown even in a badly malfunctioning reactor.
        thaumasiotes 4y ago
        Is it? It's not at all difficult to stock enough seawater to flood a terrestrial plant. What's distinguishing the submarine?

nashashmi 4y ago

It is not built yet. So it is theoretical. ... And Academic.

credit_guy 4y ago
In that case Rickover's observations don't apply at all: (1) It is simple -> nobody said NuScale's reactor is simple. It took NRC about 6 years to approve it, and in the process NuScale had to produce about half a million pages of documentation (2) It is small -> not really. It is smaller than full size reactors, but then it delivers only 50 MW, not 1GW. Per unit of electricity delivered, it is most likely somewhat larger than a full size nuclear power plant (3) It is cheap -> relative to what? it's not that cheap. If anything, see the comments in this thread, it appears to be expensive (4) It is light -> this does not apply here. Rickover was concerned with submarines, where weight was important. This is not a reactor designed for submarines. I don't know how light it is, but nobody cares about this (5) It can be built very quickly -> well, if the first one is supposed to get online in 2029, that does not seem to be very quick, does it? (6) It is very flexible in purpose (’omnibus reactor’) -> NuScale's reactor is designed to generate electricity. That's it. What is flexibility in purpose? (7) Very little development is required -> NuScale has already worked for one decade on this. It will take until the end of this decade to see one come online. Nobody claimed "very little development is required" It will use mostly off-the-shelf components -> not really. NuScale will use a Korean manufacturer that is accredited by NRC to manufacture componenets for nuclear reactors. There's nothing off-the-shelf about this. (8) The reactor is in the study phase. It is not being built now. -> it depends what "being built now" means. NuScale can't start building before it has all the approvals. It is working on getting these approvals, if this counts as "being built now", then it's being built now. More to the point. Rickover was talking about a completely different context. People venturing cheap ideas, while he needed concrete reactors for his submarines. We are in a different world. NRC is extraordinarily stringent. The fact that NuScale got their approval is a phenomenal achievement. This should not be dismissed with the same tired old quote from Rickover that gets posted on HN almost every time we talk about nuclear reactors.
- nextaccountic 4y ago

gonzo41 4y ago

Reality is harder than fiction. And people are bad at maintaining pipes.

jacquesm 4y ago

I'll answer that with another quote: "In theory there is no difference between theory and practice, in practice there is."

credit_guy 4y ago
Why the flippant quote?
- jacquesm 4y ago
  It's not flippant at all. It is the essence of the much longer version and the real lesson contained therein, you asked a question and I answered it. If you see it as flippant then that might reflect on you. Your other comment further down in this thread is flippant, even though it is a much longer one: you reject out of hand what is contained within these words without taking the time to ponder how they do apply to the matter at hand.
  - credit_guy 4y ago
    > If you see it as flippant then that might reflect on you. It does reflect on me. It reflects the fact that I can't read minds. You gave a widely known quote, and in your mind it was crystal clear what you meant. But to other people, who can't read your mind, it just sound flippant. It sounds like you think NuScale is a bunch of theoreticians. And that with your remark you are trying to put down their decade-long quest to achieve something. Maybe it does not sound flippant to you, but I assure you, it is flippant.
    - jacquesm 4y ago
      The message, to expand on it is that they are in the earlier stages of their development and the safe bet is that by the time it is all said and done things will be much more in line with what we've come to expect from the nuclear industry, including any and all of the statements already in line with that today. So by the time it is done it will be more expensive, likely heavier, likely way late, more complex and narrower in its possible range of applications. It's not a law, it is an observation made over many nuclear deployments and to the best of my knowledge there isn't a single project that was an exception so I expect it to be true this time around as well. Which is why you can safely ignore any of the touted advantages until the product is ready to be fielded in quantity. Assuming it ever will be fielded in quantity, plenty of designs were slated for large numbers of deployment and ended up being one-offs or at best single digit runs because of unforeseen issues with the design.