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This article is really light on the problem of complexity. Even relatively simple reactors have huge amounts of pipes and wires and such many of which need to

by m0llusk 11y ago

This article is really light on the problem of complexity. Even relatively simple reactors have huge amounts of pipes and wires and such many of which need to be able to handle unusual temperatures and acidity levels. This is one of the reasons that Thorium looks great on paper but is doomed in reality. The sheer complexity of even relatively simple implementations is overpowering and causes the costs and organizational challenges to make sustainable alternatives look cheap.

api 11y ago
My impression for a while has been that nuclear power is one of those techs that looks good on paper but fails in practice due to what Elon Musk calls a high "PITA factor." (Pain in the A$$) I interpret PITA factor as referring to the existence of a long tail of thorny, hard, nasty, complicated problems that do not show up on a straightforward "paper" model of the tech. Some don't show up because they're complex edge case issues, and others (like "black swan event" risk) are just flat out hard to quantify. I also think wishful thinking plays into it, since if a tech looks sexy and cool on paper there's a desire to believe in it and it leads us to overlook less obvious or less straightforward to analyze issues. Elon uses high PITA factor when talking about why SpaceX isn't pursuing hydrogen as a rocket fuel. It similarly looks awesome on paper but results in higher TCO and higher complexity in practice. It's cheaper (according to SpaceX) to use kerosene or methane and build a bigger rocket. For nukes vs. renewables it's likely overall cheaper to just over-build renewables and storage than to handle the long tail of pain from current-type nuclear. Spend a few billion dealing with nuclear waste, or spend a few billion on more generation and storage capacity. The former is sticky and complicated, while the latter is just straightforward commodity scaling of stuff everyone already knows how to build and handle. It's stupid and simple and scalable and if it's not enough just do more of it. In other words: just build a bigger rocket. What I say applies to conventional and near-term fission. Fusion and other exotics might be a different ballgame. Fusion would likely be complex and high capital cost but it doesn't have the waste and "black swan failure" issues that pee in the pool for fission.
- pdonis 11y ago
  I think the perceived "black swan event risk" of nuclear is the result of over-hyping a few incidents rather than doing a rational across the board risk assessment. When a rational across the board risk assessment is done, nuclear does less harm per unit of power generated than any other energy technology. But the harm from other technologies is distributed in space and time (for example, coal dust in the air and radioactivity in coal ash), so it doesn't get the big media play.
  - api 11y ago
    I don't disagree per se, but I think if you also factor in a lot of other sticky nasty things about current-generation nuclear power it's one of the issues that weighs it down. I also think PITA factor is kind of a death by a thousand cuts -- a "long tail" as I said.
- Pxtl 11y ago
  The thing is that overbuilding solar/wind to the point that the minimal output overcomes peak requirements is insanely expensive. Nuclear is expensive, but not as expensive as overbuilt or offshore (consistent) wind or solar.
  - tdyen 11y ago
    Solar is on a downward cost curve. Every doubling of installed cells leads to I think %20 cheaper costs.
- deleted 11y ago
  [deleted]
pdonis 11y ago
I think you're over-generalizing from earlier generation designs. Newer designs are simpler because they take advantage of new design features that replace complex, "active" devices with simple, "passive" ones. For example, replacing active emergency cooling with passive emergency cooling removes a big chunk of complexity from newer designs. Also, complexity in and of itself can be handled. The issue is that handling it requires discipline, and for civilian nuclear power in the US, the discipline has often not been there. (By contrast, military nuclear power in the US has always had strong discipline, and as a result relatively complex reactors are run safely.)
- eli 11y ago
  I don't disagree, but at the same time I'm sure the people setting up Fukushima thought they had a high-tech fail-safe plant that wasn't like the old designs...
  - pdonis 11y ago
    > I'm sure the people setting up Fukushima thought they had a high-tech fail-safe plant that wasn't like the old designs No, they thought they could site the backup diesel generators and switchgear behind a seawall that turned out not to be high enough when a tsunami came through. None of the issues at Fukushima had anything to do with the design of the reactor itself; in fact, the reactor was obviously significantly over-engineered given how well it withstood an extended loss of backup cooling.
    - eli 11y ago
      Arguing whether it's the design of the plant or the design of the reactor seems like purely semantics. I'm sure they thought the seawall was high enough when they built it. Why are we now so sure we couldn't make a similar miscalculation?
      - pdonis 11y ago
        > Arguing whether it's the design of the plant or the design of the reactor seems like purely semantics. Not if the public's reaction is "Aah, nuclear bad, no more nuclear!" instead of "hey, idiots, you need to change your specs for seawalls". > I'm sure they thought the seawall was high enough when they built it. The problem was that their definition of "high enough" was wrong. That's not a matter of reactor design, or even an issue that's specific to reactor design; it comes up in any issue involving cities or facilities near seacoasts (for example, specs for levee heights). But in every other area that's affected by this issue, the response is "you need to change the specs for how severe an event the facility needs to withstand", not "stop building this facility altogether". Nobody argues for abandonment of all coastal cities because some levees aren't high enough. > Why are we now so sure we couldn't make a similar miscalculation? Who said we were? There is no such thing as zero risk.
philliphaydon 11y ago
But the molten salt reactor doesn't require people monitoring and fail overs because it doesn't rely on being cooled. If the system fails the liquid just drains off.

by m0llusk 11y ago

api 11y ago

My impression for a while has been that nuclear power is one of those techs that looks good on paper but fails in practice due to what Elon Musk calls a high "PITA factor." (Pain in the A$$) I interpret PITA factor as referring to the existence of a long tail of thorny, hard, nasty, complicated problems that do not show up on a straightforward "paper" model of the tech. Some don't show up because they're complex edge case issues, and others (like "black swan event" risk) are just flat out hard to quantify. I also think wishful thinking plays into it, since if a tech looks sexy and cool on paper there's a desire to believe in it and it leads us to overlook less obvious or less straightforward to analyze issues. Elon uses high PITA factor when talking about why SpaceX isn't pursuing hydrogen as a rocket fuel. It similarly looks awesome on paper but results in higher TCO and higher complexity in practice. It's cheaper (according to SpaceX) to use kerosene or methane and build a bigger rocket. For nukes vs. renewables it's likely overall cheaper to just over-build renewables and storage than to handle the long tail of pain from current-type nuclear. Spend a few billion dealing with nuclear waste, or spend a few billion on more generation and storage capacity. The former is sticky and complicated, while the latter is just straightforward commodity scaling of stuff everyone already knows how to build and handle. It's stupid and simple and scalable and if it's not enough just do more of it. In other words: just build a bigger rocket. What I say applies to conventional and near-term fission. Fusion and other exotics might be a different ballgame. Fusion would likely be complex and high capital cost but it doesn't have the waste and "black swan failure" issues that pee in the pool for fission.

pdonis 11y ago
I think the perceived "black swan event risk" of nuclear is the result of over-hyping a few incidents rather than doing a rational across the board risk assessment. When a rational across the board risk assessment is done, nuclear does less harm per unit of power generated than any other energy technology. But the harm from other technologies is distributed in space and time (for example, coal dust in the air and radioactivity in coal ash), so it doesn't get the big media play.
- api 11y ago
  I don't disagree per se, but I think if you also factor in a lot of other sticky nasty things about current-generation nuclear power it's one of the issues that weighs it down. I also think PITA factor is kind of a death by a thousand cuts -- a "long tail" as I said.
Pxtl 11y ago
The thing is that overbuilding solar/wind to the point that the minimal output overcomes peak requirements is insanely expensive. Nuclear is expensive, but not as expensive as overbuilt or offshore (consistent) wind or solar.
- tdyen 11y ago
  Solar is on a downward cost curve. Every doubling of installed cells leads to I think %20 cheaper costs.
deleted 11y ago
[deleted]

pdonis 11y ago

I think you're over-generalizing from earlier generation designs. Newer designs are simpler because they take advantage of new design features that replace complex, "active" devices with simple, "passive" ones. For example, replacing active emergency cooling with passive emergency cooling removes a big chunk of complexity from newer designs. Also, complexity in and of itself can be handled. The issue is that handling it requires discipline, and for civilian nuclear power in the US, the discipline has often not been there. (By contrast, military nuclear power in the US has always had strong discipline, and as a result relatively complex reactors are run safely.)

eli 11y ago
I don't disagree, but at the same time I'm sure the people setting up Fukushima thought they had a high-tech fail-safe plant that wasn't like the old designs...
- pdonis 11y ago
  > I'm sure the people setting up Fukushima thought they had a high-tech fail-safe plant that wasn't like the old designs No, they thought they could site the backup diesel generators and switchgear behind a seawall that turned out not to be high enough when a tsunami came through. None of the issues at Fukushima had anything to do with the design of the reactor itself; in fact, the reactor was obviously significantly over-engineered given how well it withstood an extended loss of backup cooling.
  - eli 11y ago
    Arguing whether it's the design of the plant or the design of the reactor seems like purely semantics. I'm sure they thought the seawall was high enough when they built it. Why are we now so sure we couldn't make a similar miscalculation?
    - pdonis 11y ago
      > Arguing whether it's the design of the plant or the design of the reactor seems like purely semantics. Not if the public's reaction is "Aah, nuclear bad, no more nuclear!" instead of "hey, idiots, you need to change your specs for seawalls". > I'm sure they thought the seawall was high enough when they built it. The problem was that their definition of "high enough" was wrong. That's not a matter of reactor design, or even an issue that's specific to reactor design; it comes up in any issue involving cities or facilities near seacoasts (for example, specs for levee heights). But in every other area that's affected by this issue, the response is "you need to change the specs for how severe an event the facility needs to withstand", not "stop building this facility altogether". Nobody argues for abandonment of all coastal cities because some levees aren't high enough. > Why are we now so sure we couldn't make a similar miscalculation? Who said we were? There is no such thing as zero risk.

philliphaydon 11y ago

But the molten salt reactor doesn't require people monitoring and fail overs because it doesn't rely on being cooled. If the system fails the liquid just drains off.