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  1. Rod – any chance we could see a picture of your fuel pellets that you mention in the show? … and what are their dimensions and weight?

    Just interested

    All the best

      1. Oh that’s great thank you.

        I’m was trying to get numbers for mass density. Do these sound about right

        uranium metal 19g/cm3
        uranium oxide fuel pellet 10g/cm3
        uranium fuel rod 10g/cm3 (about the same, cladding doesn’t contribute much)
        yellow cake 10g/cm3
        uranium ore – varies massively perhaps 5g/cm3 (denser than most rock which is usually 2-3g/cm3)

        1. Much appreciated. I did try that, but there are conflicting numbers over the internet. So I thought I’d ask. Maybe yellowcake, as it is transported, is a long way from being pure U3O8. I don’t know. If there’s anyone from Kazakhstan who could help me out…

          As for the density of a uranium fuel pellet, sorry if I’m a little late to catch on to this, but if uranium dioxide is 10g/cm3

          and a fuel rod is 4m long and cross section of 1cm3

          then a fuel rod weighs about 4kg

          of which about 3% is U235

          which is 120g of U235

          which contains (6 x 10^23) x (120/235) atoms of U235

          which equals 3×10^23 atoms of U235

          which when fissioned gives off (3×10^23) x (200 Mev) x (1.6×10^-19 J) / 3.6×10^6 kwh

          which, with a thermal efficiency of about a third, gives about 1 million kwh of electricity.

          (not all U235 is fissioned in a fuel rod, but that which isn’t is made up for by Pu239)

          ————————————————————————————————-

          in the USA you use about 12-13,000 Kwh of electricity per capita per year.

          or 1 million kwh per lifetime.
          ————————————————————————————————-

          which means if USA was 100% nuclear, when you shuffle off this planet, after a lifetime of electricity consumption, all you would leave behind you is one sole uranium fuel rod.

          Personally, I find that not only amazing but quite beautiful. I would quite like my name engraved in “my” fuel rod before it is put in a reactor, be allowed to go and visit it when it is in spent fuel pool, and finally be present to give thanks and pay my respects when it goes into dry cask storage. It has, after all, done far more work than I ever did.

          …it certainly sounds much better than leaving behind 1000 tonnes of supercritical CO2 in some CCS salt dome. Fission is the new fire as someone likes to say.

  2. “which means if USA was 100% nuclear, when you shuffle off this planet, after a lifetime of electricity consumption, all you would leave behind you is one sole uranium fuel rod.”

    So if the US went 100% nuclear fission, there would be 300 million fuel rods to deal with. This does require a certain amount of organisation.

    From the point of view of the power companies, the end products from burning gas just blow away, and need no storage or handling. The companies are not bothered about climate change. Not their problem. If temperatures do go up, it increases the sales of power for air conditioning.

    One can see the attraction of gas.

  3. So if the US went 100% nuclear fission, there would be 300 million fuel rods to deal with. This does require a certain amount of organisation.

    Any modern society composed of 300 million people is going to require a certain amount of organization. Keep in mind that’s over the span of 78 years (the average life span in the US). Mankind has known about the neutron for only 80 years.

    A fuel rod might seem like a lot of material, because of its length, but that’s misleading. The volume of one rod is about the same as the volume of a standard soft-drink can or less, depending on the design. A single 8.5″×8.5″×13.3′ Westinghouse fuel assembly holds 264 of these rods.

    To give you some perspective, in just 2011 alone, Americans purchased over 9 billion cases (not cans) of carbonated soft drinks.

  4. T Boone Pickens wants to convert all vehicles engine to natural gas … He also admitted yesterday that he ‘lost his shirt with wind and that it will never work’.

  5. I agree. Since USA started making nuclear electricity commercially it has produced approx. 25 trillion kwh of electricity.

    With my new-found calculation tool. I can quite easily say that it has produced in the region of 25 million spent fuel rods. If you were to store those end on then it would fill 50metres x 50metres (and 4metres high). Half the size of a football pitch and just above the height of the goal posts.

    If you were to put them in dry cask storage. I think the area required would go up by a factor of 20. And so 10 football pitches covered with these.

    and those 10 football pitches would take up less room on this map than one of those dots.

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