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  1. #14
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    Quote Originally Posted by Dr.phil View Post
    KCA, what do you think about the small modular units developed at Oregon State University?
    Sort of like these little guys; http://www.nextenergynews.com/news1/...ar-12.17b.html

    The HVAC industry needs to get in on the ground floor installing these gems.
    Government is a disease...
    ...masquerading as its own cure…
    Ecclesiastes 10:2 NIV


  2. #15
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    Jan 2011
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    Lynchburg, VA
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    I had something written up, but I lost the post...

    Let's try again:

    Calvert Cliffs: Not exactly. I haven't been to the site, but have worked a bunch on a new design that they would like to build there and also some engineering work for the existing units.

    Waste: It is more political than technical. You see, used fuel still has a ton of good fuel in it. What you need to do is separate out the good from the bad and reuse the good. France and the UK do this as they have nowhere for the waste.

    http://en.wikipedia.org/wiki/Nuclear_reprocessing

    We currently don't do this and instead have to keep the fuel onsite at most plants. This means that most plants have 30+ years worth of fuel sitting in the pools or in dry storage onsite. You could never do this with the ash from a coal plant, but we can get by with nuke since it uses much less fuel than other sources. We still need to get something setup as it makes it nearly impossible to shutdown the plant at the end of life as you have nowhere to stick the fuel.

    Modular reactor: I like 'em. They might not work out for commerical operation in the US (at least for now) since typically you need one control room per reactor. However, these would be idea to power military bases and remote locations. I know the OSU desgin well. I was involved in testing the design.

  3. #16
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    Quote Originally Posted by KCA View Post
    Modular reactor: I like 'em. They might not work out for commerical operation in the US (at least for now) since typically you need one control room per reactor. However, these would be idea to power military bases and remote locations. I know the OSU desgin well. I was involved in testing the design.
    Weren't you afraid of becoming the Hulk? Or did they lie to us about that too?
    Government is a disease...
    ...masquerading as its own cure…
    Ecclesiastes 10:2 NIV


  4. #17
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    The initial testing rig was non-nuclear. Scaled down and used electric heaters (~700kW) to test operation.

    OSU does have a nuclear research reactor (TRIGA, mkII). This is a 1.1 MW steady-state reactor. It can be pulsed and produce power levels up to ~3000MW for very short periods. It isn't used to produce electricity or anything. It is used as a neutron source for experiments.

  5. #18
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    Oct 2009
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    Thanks for stepping up Kent, and sharing your knowledge and views. I have long been a proponent of nuclear power, it is the future. The disaster in japan was foreseeable and caused by greed in my book.

  6. #19
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    Lynchburg, VA
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    With Japan, what I find impressive is how well everything stood up to the disaster. It is really pretty impressive when you thing about it. A 9.0 quake plus a giant wave of water...some serious forces at work there.

    Most of what did end up happening probably won't have happened in the US. These plants had extensive modifications after TMI. One modification was a hardened vent line to the outside to release the hydrogen (would have avoided the explosions) and also the switchgear and emergengy diesel tanks are in hardened areas with water-tight doors. These mods must not have been made on the plants in Japan.

    Anyway, when things like this happen, we go back andi look how to make things better. Safety is always #1 priority in this industry. We are already looking at things like extended periods without power and whether you could have common-cause failures that we hadn't looked at before. Normally, we wouldn't consider two major disasters at one time, but Japan showed that you can get two disasters together.

    We'll learn from this and continue to improve.

  7. #20
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    Quote Originally Posted by KCA View Post
    Okay. Thorium fuel cycle. I figured that you might have been talking about fusion. Anyway, thorium has some advantages. However, everything is setup for a uranium cycle and there isn't really a problem with the uranium supply at this time. Not to mention, there is a ton of energy stored in the waste that has already been generated. The good stuff could be separated out and tossed back in to burn again.

    Currently fuel is only a small % of the operating cost of the plant. Although it is somewhat expensive in terms of $$, about 1/3 of the core is changed out every 18-24 months where say a coal plant needs to be fed constantly, so refueling is infrequent.

    In order to see a thorium cycle, there will have to big a massive increase in the price of uranium. There is nothing wrong with using thorium, but there isn't much incentive to use it since everything is already setup for uranium.
    Or a big accident....

    Roy
    "The perfect Totalitarian State is one where the political bosses, and their army of managers, control a population of slaves, who do not have to be coerced, because they love their servitude"

  8. #21
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    Quote Originally Posted by RoBoTeq View Post
    Evidently, according to what's happened in Japan, all we have to do is dump it into the ocean.

    Either we have been duped big time about how dangerous radiation from nuclear reactors is when it is released or we are being duped as to how safe we are now that so much radioactive material has been dumped by the Japanese reactor. If the former, it is just another of many lies to keep us in a state of fear so we can be more easily controlled. If the latter, then we are being lied to in order to keep us from becoming uncontrollable due to a real danger. Either way, we have been manipulated big time about nuclear power.
    Hitachi says that it will take 10 years to decommission the site and 30 years to return it to greenfield conditions. That is as long as no other natural disaster hits the site.

    Toshiba says 10 years to greenfield conditions. Funny the estimates vary that much.

    http://www.nytimes.com/2011/04/17/wo...17cleanup.html

  9. #22
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    Quote Originally Posted by printer2 View Post
    Hitachi says that it will take 10 years to decommission the site and 30 years to return it to greenfield conditions. That is as long as no other natural disaster hits the site.

    Toshiba says 10 years to greenfield conditions. Funny the estimates vary that much.

    http://www.nytimes.com/2011/04/17/wo...17cleanup.html
    When estimates vary that much, the reality is that they have no clue.
    Government is a disease...
    ...masquerading as its own cure…
    Ecclesiastes 10:2 NIV


  10. #23
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    Seems to me the most important safety feature other than structural integrity is back up cooling water. So long as the fuel has adequate cooling, no melt down. I'm surprised that the japanese plants did not have several back up cooling systems.

    This correct KCA?

  11. #24
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    Right. Cooling water is #1. With the plants in Japan, the problem wasn't really due to a lack of pumps, but a lack of power instead. Normally, there are two independent connections to the electrical grid for power (called offsite power). This got taken out with the quake/tsunami. The plants also stopped producing power like they were supposed to (turbine trips, control rods inserted into the core to shutdown the chain reaction, etc.). So, with both of these power supplies taken out, your next source of power is there are several emergency diesel generators that can fire up and provide power. However, these were in a room that got flooded and some of the diesel tanks were washed away (these generators and diesel tanks are protected (from flooding and impacts) in the US plants). So, now the ony thing left is they have a room filled with batteries to power the basic safety systems. However, typically you would only need to size the batteries for 4 to 8 hrs worth of power. The idea is that within that time you could get a generator going or somehow restore power. This wasn't the case as so much was destroyed plus the debris made access nearly impossible. Remember that also roads and nearly everything else was destroyed making it impossible to truck in a generator large enough to pick up the load for the pumps.

    Although there was backup of backup of backups, the combination of events was enough to knock them all out.

    This shows some of the modifications that were made to the US plants of this design. It appears that these changes were not made in those plants in Japan.

    http://resources.nei.org/documents/j...usbwr_4511.pdf

  12. #25
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    Seems Japan could have used a helicopter to bring in a skid with a portable generator affixed on it, from a nearby military base, to power up the facilities or was that too difficult to figure out?

  13. #26
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    Quote Originally Posted by 5 star View Post
    Seems Japan could have used a helicopter to bring in a skid with a portable generator affixed on it, from a nearby military base, to power up the facilities or was that too difficult to figure out?
    That was the very first thing they figured out. With all that was going on from nature, it wasn't quite as easy as you make it sound. The U.S. even had generators available and ready to use, but the Japanese government did not want outside intervention until they figured out exactly what was going on.

    Maybe you can send them your phone number so they have someone to call who can figure those difficult things out for them
    Government is a disease...
    ...masquerading as its own cure…
    Ecclesiastes 10:2 NIV


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