Tuesday, January 31, 2012

Episode 2: Dr. Alan Glasser

Our sophomore episode is now live! I talk with Dr. Alan Glasser from the University of Washington's PSI (Plasma Science and Innovation) Center. We discuss nuclear science, nuclear power, science in general and religion. Exciting stuff. Click the play button below to make it happen:

XML/Podcast feed to follow shortly. In the meantime, if you'd like the download the file for later, click here.


  1. Russell's dad! Interesting interview, all the numbers involved with nuclear power are staggering.

  2. While he might be an expert in nuclear fusion, it appears his knowledge of modern fission reactor technology is non-existent.

    Starting around 13:40

    “The existing [nuclear] power plants – all existing power plants – you must actively cool them [...]”

    This is correct.

    “- in order to prevent the reaction from running away.”
    “The chain reaction.”
    “Yes. There is a fundamental property of these designs which is called I think a positive coefficient of reactivity which means that if you make it hotter then the rate of reaction increases.”

    This is dead wrong. I’ll stop transcribing by hand, but he continues talking while being completely wrong.

    Basically all modern light water reactors (the great majority of modern reactors) have a negative void coefficient, which means as it gets hotter the reaction slows down. (Ok, CANDUs may have a slight positive coefficient, but they’re an uncommon technology. And no Fukushima wasn’t a CANDU.) See:


    He mentioned by Chernobyl, Fukushima, and Three Mile Island. He got only 1 of the 3 right. Chernobyl did have a positive void coefficient, but no one in 50 years has ever made such a retarded reactor design. Fukushima and Three Mile Island did not, contrary to his explicit statements. Take Three Mile Island, for example:

    “Within eight seconds, control rods were inserted into the core to halt the nuclear chain reaction”

    Aka end of nuclear fission.

    “but the reactor continued to generate decay heat and,”

    Fission ended, and thus the negative void coefficient thus became irrelevant. However, the fission products are unstable and spontaneously decay (not fission), generating heat. This is what requires cooling in the event of an emergency when fission is shut down. The byproducts eventually decay away to stability, but in the meantime this does produce a lot of heat, and there’s no way to “turn it off”. If you don’t constantly cool the fission products, then the heat builds up, and the heat is so intense that it can melt the fuel cladding, melt the reactor walls, and get out.

    I’m too lazy to whip up one of the official reports for Fukushima, but it’s the same. As soon as the automatic sensors detected an earthquake, the control rods were inserted, and fission stopped dead. The heat from the decay of the fission products is the difficult part to deal with.

    Also, he claims all current fission reactors have fundamental flaws. That’s curious considering nuclear (fission) power is by far the safest and greenest energy choice available. Less people have died from nuclear ever (excluding Chernobyl which doesn’t count for various reasons) than from a single coal mine accident. New designs, such as IFR and LFTR might make it even the cheapest too.

    Finally, he ignores various other possible fission designs, such as IFR and LFTR, which have fundamentally different (and better) safety characteristics. It is very sad indeed to see a supposed expert lump mostly unrelated technologies together and ignorantly dismiss them all. See energyfromthorium.com for additional information.

  3. Actually, in Canada, to get a reactor licensed you must prove that the reactor has a negative temperature coefficient of reactivity. I am quite sure it is the same in the U.S. and most of the world.

    You claiming the opposite discredits the rest of your argument.

    1. Quoting Ed:
      "Actually, in Canada, to get a reactor licensed you must prove that the reactor has a negative temperature coefficient of reactivity."

      That's not right... See:

      "All power reactors built in Canada are of the CANDU type."

      I'm not sure offhand how accurate that is, but AFAIK CANDUs exist in Canada, and CANDUs do have a slight positive coefficient of reactivity. (They're still quite safe due to the heavy water slowing everything down and multiple redundant backups.)

    2. Yes, CANDU's (CANada DUterium)are Canada's national reactor.

      A positive VOID coefficient of reactivity. Which means if voids form in the coolant/moderator (D2O) reactivity will go up.

      I am talking about a TEMPERATURE coefficient of reactivity. Which CANDU's and most all nuclear reactors require to be negative. Meaning if the temperature rises, the reactivity goes down.

      The expert claims that if the temperature rises, the reactivity will go up, which is not true unless water starts to boil.