• Cosmic Cleric
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    11 year ago

    Buildings and machinery fatigue and wear out over time.

    And highly critical uptime devices and buildings need extra maintenance and upkeep.

    Old sites need to be decommissioned. Even if you ignore the financial costs in the upkeep at some point they just fatigue to the point of needing to be replaced.

    I’m not anti-nuclear, all I’m saying is if you want nuclear you have to build new sites, you can’t keep the old sites going forever.

    • @[email protected]
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      11 year ago

      Rotating equipment are replaceable is not that much of an issue they operate on regular steam.

      Buildings are reinforced concrete unlikely to be a concern not in a reasonable timeframe unless rebars corrode for some reason.

      Issue would be items operating with water directly in contact with the reactor, so critical piping, heat exchangers and reactor vessels, which I can’t say I am an expert specifically for nuclear plants.

      I imagine the main concern would be the reactor itself as all reat can be replaced.

      • Cosmic Cleric
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        11 year ago

        Not to argue minutia, as it doesn’t take away from my correct point, but I was speaking specifically of the reactor and it’s housing and the building around it. A reactor when it’s built has a pre-planned age limit to it.

        • @assassin_aragorn
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          11 year ago

          We can do calculations to evaluate them. If someone creates a fairly accurate or at least conservative stimulation of the reactor and housing, a mechanical engineer should be able to determine if it’s still good for operation or needs replacement. They use ASME code and tables to do life fraction calculations.

          • Cosmic Cleric
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            31 year ago

            Fair enough. This article basically covers both the points you are making, as well as the point that I am making.

            For the record, I believe that the longer we can use things the better. But the fatigue that a reactor takes due to radiation damage (described in the article) would make it seem like a reactor has a definate finate expiration date, like most mechanical devices we humans make. Its just a matter of how much you want to push things, how much of a safety margin you want, etc.

            • @assassin_aragorn
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              11 year ago

              Most things operating in industrial processes are going to have finite lifespans with the heats and stresses that are applied to them 24/7, plus in this case radiation. You’re completely right about safety margin too. I used to run these simulations for mechanical engineers, and they’d always apply some safety factor. The challenge is is making sure that you’re getting the most out of the material while still not compromising on safety.

              All of that said, the analysis relies on tabulated data from the ASME code. I doubt they have the data necessary on radiation deterioration to do these detailed calcs. Assuming they don’t, I think you’re right that it would be prudent to retire them at this point.

              • Cosmic Cleric
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                11 year ago

                All of that said, the analysis relies on tabulated data from the ASME code. I doubt they have the data necessary on radiation deterioration to do these detailed calcs.

                The article that I linked goes into some detail about their understanding how radiation affects the containing material around it and what’s required to repair it, and the rate that it fatigues. I believe that’s the “layman’s version” of the data you’re looking for.