Nuclear Power to lead the U.S. to Clean Energy Independence?

Discussion in 'Archive: The Senate Floor' started by Ghost, Jun 25, 2010.

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  1. SithLordDarthRichie CR Emeritus: London

    Member Since:
    Oct 3, 2003
    star 8
    Thing is, although the total number for tha nation would exceed demand, each parking lot probably wouldn't have enough panels to power that many homes. You could have 5 parking lots within 10 miles but they may only be big enough for you to get 200 homes of power out of them individually, if not less.
    OK powering small parts can be good because then you have less energy demand for you larger scale power source such as nuclear.

    Look at London - It has a densely populated central area with lots of big buildings and cars & people. Greater London on the other hand has a lot of people but they are more evenly spread about and have generally smaller houses and less power demand.
    Using Solar of Wind Power to give electricity to those homes means that you'd need fewer nuclear power stations to give Central London its energy. This is cheaper and more efficient.

    Of course, Solar Panels do have to be renewed in time, but so will Nuclear Power Stations once Fusion Reactors are efficiently created.
  2. Lowbacca_1977 Jedi Master

    Member Since:
    Jun 28, 2006
    star 6
    Oh, there's other options that would also work, of course, my point was more that we have a lot of land that solar panels could be put in on that isn't really being used otherwise that could be utilised for this. Although on some rough back of the envelope calculations, the 3 largest parking lots within 1.5 miles of my house look like they would be able to cover about 1000-1100 houses. (the two largest being around 450 homes each)


    And of course, I don't have an objection to nuclear, either, but my point is largely that with stuff like solar, people are too quick to throw up their arms with a "oh, this takes up too much space and will never work" without some of the possible solutions ever really being discussed.

    And I'd also toss in that for wind power, because it's well situated for it, Palm Springs in California has over 4000 turbines, which according to some things I'm finding, apparently takes care of not only the energy demands of Palm Springs itself, which has a population of around 40,000 but the entire Coachella Valley, a population of around 600,000. And some other sources indicate that, again, this is land that can be used for dual purposes, apparently agriculture can work well with the same land.
  3. SithLordDarthRichie CR Emeritus: London

    Member Since:
    Oct 3, 2003
    star 8
    The Hoover Dam generates a lot of power. I think Hydro-eletric and Wave power is a very efficient way to do things.
    The problem is that building lots of dams can cause problems so it needs lots of planning. Wave power though only needs to go on the water surface or somewhere there is a strong current.

    Perhaps the Gulf Stream can be utilised better.
  4. Darth_Yuthura Jedi Padawan

    Member Since:
    Nov 7, 2007
    star 4
    Then why hasn't it been done already? The limiting factor for just about everything is economics. Wave power just isn't cost effective and it likely won't be until other sources become WAY more expensive than they already are.

    Although I do also favor using waves and tidal energy over wind in most cases, it just has many complications that make it too expensive to build and maintain. The second is where wind energy looses its luster. It may be free, but keeping the turbines running is another matter.
  5. SithLordDarthRichie CR Emeritus: London

    Member Since:
    Oct 3, 2003
    star 8
    Hydro-electric power can have bad environmental effects if not properly managed.

    Sticking a huge rotating device under the sea to make energy is fine, but it won't get good reception if Marine Life is being chopped into pieces by it. Wave power has still yet to be made very weather-proof as far as I can see (bad storm or big waves and the stuff stops working).

    A lot of these alternatives have to overcome cost & reliability issues before they become decent long-term solutions.
  6. Lowbacca_1977 Jedi Master

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    Jun 28, 2006
    star 6
    I'd absolutely agree that a lot of our opportunities for alternative power require further development first.
  7. VadersLaMent Chosen One

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    Apr 3, 2002
    star 10
  8. VadersLaMent Chosen One

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  9. Ghost Force Ghost

    Member Since:
    Oct 13, 2003
    star 6
    I sent an email to the Department of Energy, a version of my original post here. I didn't really expect a detailed answer, or even something more than a general "thank you for your interest" response... but they provided one, here it is copy and pasted from the email. I think it's very interesting.



  10. Neo-Paladin Jedi Master

    Member Since:
    Dec 10, 2004
    star 4
    OK, a couple of comments from a Nuke Engineer late to the party:
    A huge hurdle is simply economics. It's true no new nuke power plant has been built since TMI accident, but the argument can be made that's more about economics rather than anti-nuke fears. Nuke plants have always been built on the ~1000 MW scale, as nuke plants benefit from economies of scale, bigger means more profit sooner. However a plant on that scale is very pricey, and no coal plants on the ~1000 MW scale have been built since the TMI accident either. Both are pricey. I saw a talk from Dominion power, the first or second largest operator of nuclear power plants. They laid out that they would have to almost the entire company up as collateral to build a single plant of that size. While today's operators of nuclear power plants see them a cash cows, investors have enough memory to remember what happened to the builders of those power plants (most lost everything and sold the plants at below cost).

    But, there is a light on the horizon. A modular 100 MW reactor has been designed and is going through licensing. Assuming it gets licensed, and factory style construction of a nuclear power plant can be demonstrated to bring down costs (Those 104 power plants? Every one is unique. No modularity at all. Say it with me: insane) this could very well break the economics dead lock.

    On to uranium issues. There are two things to keep in mind here.

    First, spent fuel can be reprocessed. When a fuel rod is 'spent' less than 10% of the uranium in the rod is burnt up. Reprocessing is a known quantity; France and Japan do it today. The US doesn't for non-proliferation reasons, which is more political than technical. Accessing this waste as a resource would be huge, and should be seriously undertaken in the US today.

    Second, it is possible to extract Uranium from the ocean salts. Japan has experimented with this, and estimate the cost will be much higher than mined uranium (~$240/kg, via wikipedia), but still cost effective for fission power plants. At the moment I rather think we should try to find better ways to mine, but there are other options if mining can't be done ecologically.

    Also, the terrorism threat is fairly neutral. Nuclear power plants are not attractive targets to terrorists. They are hardened and secured sites with well trained and armed guards. Further, the containment domes are built to withstand head-on airplane impact.

    All this is not to say I'm without reservations (despite being a nuclear engineer). US nuclear power plants have a stellar safety record, despite a near miss or two. But if the gulf spill has a lesson, it should be that your contingencies must be equal to your worse case scenario. Western reactors are built such that the worst case is orders of magnitude less catastrophic than Chernobyl, and it's not like we don't take risks every day (just getting into a car if nothing else). All that said, I want more reactors to be passively safe, that is shut down all the pumps, pull out all the fuel rods and the thing physically can't melt down. After that, the only concern is corrosion leading to an escape of radioactive material (see the near miss above). You're never going to eliminate all the reasons to worry, but we can make sure we're capable of handling the worst case imaginable.

    I hope this added more light than heat to the discussion.

    Also, on ocean current turbines I've seen pitched, they all use v. high torque, slow speed blades (really they're more like wings than blades) to keep the ocean life from being chummed.
  11. Jabbadabbado Manager Emeritus

    Member Since:
    Mar 19, 1999
    star 7
    Re the DOE letter (great read), the level of investment needed is staggering, but would not have to be invested all at once of course. The biggest concern I think is whether the global uranium supply can really be ramped up to support the nuclear power aspirations of China and the United States if the U.S. were to make nuclear power the backbone of a renovated power grid.
  12. Darth_Yuthura Jedi Padawan

    Member Since:
    Nov 7, 2007
    star 4
    This is in regards to US reactors. France did not make this mistake, as all their reactors share a common design wherever possible. This greatly reduces their cost and construction time. Remember that these kind of projects are bought with borrowed capital and are paid for throughout the life of the power plant. Solar power is dirt cheap, but it demands an enormous investment of capital. That is what makes solar and wind so expensive, despite being so cheap to operate.

    Nuclear energy does prove to be the best source of energy, although it does come with an enormous capital investment. All the US has to do is follow the same kind of model for their nuclear reactors as France and they can mimic their success almost instantly. They have only to adopt a single design and use it for all future power plants.

    VERY expensive to reprocess spent fuel. And remember that the majority of the uranium in fuel rods is U-238, which can't be used in conventional reactors. Fast breeder reactors are a much better solution, as they can make use of this otherwise worthless material. Only issue is related to cost, which make heavy-water reactors a more economic choice than breeder reactors.
  13. Neo-Paladin Jedi Master

    Member Since:
    Dec 10, 2004
    star 4
    On reprocessing, from what I've read, a ~$0.0013/kWh increase in cost would seem to be worth the expence of minimizeing the amount of uranium mined. Enrichment levels are built in to the process of blending new fuel rods, so the majority U-238 isn't an issue.

    Getting a breeder reactor going in the U.S. will have it's own difficulties, make no mistake. It'll be worth it, but most of the NE's I've talked to about fuel cycles indicate they would put reprocessing ahead of a breeder reactor. For one thing the former would feed the latter.
  14. Darth_Yuthura Jedi Padawan

    Member Since:
    Nov 7, 2007
    star 4
    Reprocessing isn't like recycling old fuel rods and using the unspent uranium again. It's often melting down the nuclear fuel and mixing it in with a slurry of materials that would dilute the uranium and plutonium biproducts into a vitrified substance. This would make it far safer to bury spent fuel, as it also eliminates the threat of radiation contamination.

    The problem here is that such a facility would be an astronomical expense to build, let alone operate. Japan still doesn't do this for the majority of its spent nuclear fuel.
  15. Neo-Paladin Jedi Master

    Member Since:
    Dec 10, 2004
    star 4
    Ummm, my understanding is not aligned with yours.

    Reprocessing is absolutely about separating uranium (and plutonium with current technology, but we'd rather not do that for proliferation reasons) from the fission products, and blending the uranium into new fuel rods. The fission products (and possibly the plutonium, if you aren't going to burn it) are then vitrified as you suggest. It's expensive and chemically kind of messy, but it reduces the volume of waste and uranium consumed significantly. Recovering unreacted uranium from irradiated fuel rods for use in new fuel rods is the whole point of reprocessing (well, that and the military does it to get plutonium for their hydrogen bombs, but that's periphery).

    Consider the summary of the American Nuclear Society manual on the subject for verification.
  16. Darth_Yuthura Jedi Padawan

    Member Since:
    Nov 7, 2007
    star 4
    Spent fuel rods probably only represent about 1 or 2% U-235. Naturally occurring uranium is only about .5%, so there really isn't a significant recovery of U-235 for the efforts you would need to extract it from spent fuel rods. And don't forget about the radiation and other byproducts. Unless we get to a point where uranium mines and fuel rod fabrication facilities are overtaxed, naturally-occurring uranium will continue to be the favored method of producing nuclear fuel.
  17. Alpha-Red Jedi Grand Master

    Member Since:
    Apr 25, 2004
    star 5
    Didn't this guy just say he was a nuclear engineer? Are you sure you want to argue with him? :p
  18. Darth_Yuthura Jedi Padawan

    Member Since:
    Nov 7, 2007
    star 4
    I'd say I'm well versed on the subject. And I have to question the content of anyone who references wikipedia, especially from a person who claims to be an expert on the subject.

    If he is a nuclear engineer, then he must be very new to the subject.
  19. Lord Vivec Force Ghost

    Member Since:
    Apr 17, 2006
    star 8
    I use wikipedia references all the time when discussing physics - if they're correct.

    You thinking the wrong thing. If he's quoting wikipedia, it's not that he doesn't know what he's talking about; it's that he's seen that the wiki information is correct and thus is quoting it.
  20. Neo-Paladin Jedi Master

    Member Since:
    Dec 10, 2004
    star 4
    Well, it's good to try to reach a common understanding.

    All reactors all run at some level of enrichment, that is the concentration of U-235 is above natural abundance. In most civilian reactors it's something like a few percent of the uranium in the rod is U-235. However, when a fuel rod is 'spent' the rule of thumb is 1% of the U-235 has been fissioned (I had to look that rule up edit and since aspersions are being cast on my references, I referenced "Nuclear Power: Villain or Victim? 2nd Ed. by Prof. Emeritus Max Carbon, UW-Madison). The rod must be taken out of the reactor because it is too hot, not because it has run out of U-235. So, yes when uranium from a spent fuel rod is blended into a new rod that 1% of the previously burned U-235 must be replaced with U-235 from another source (a mine or a decommissioned weapon).

    Here's the thing that makes reprocessing really attractive: waste. Say we keep nuclear power at 20% of the US's electricity production with moderate increase in electricity generation over 100 years. To store the waste from the past 50+ years and the next 100, without reprocessing, we'd need something more than 10 Yucca Mountain sized repositories to handle the waste. With reprocessing we'd only need 1, and we wouldn't have to mine as much Uranium either, keeping the cost of uranium mining low. That's without burning the waste in a burning reactor (aka a breeder reactor).

    Part of the bizarre thing about the US nuclear power policy is the Federal government owns and is responsible for disposing the waste. This is a responsibility it is in no hurry to assume. So the waste sits in a limbo state. If the generators were responsible for the waste we'd see a very different situation. Then someone would have a financial incentive to figure out what to do with the waste, namely reprocess, and yes, if the reactor could get licensed and built, consume the plutonium and fission products with fast neutron flux burner reactors (or fusion reactors. Don't laugh). We'd do it not because the uranium would be cheaper than mined uranium, it wouldn't be; we'd do it because it would get the waste off of our hands, and because we're not throwing uranium away it would keep uranium cheep.

    Also, to be clear on one thing, if we had burner reactors, we'd need reprocessing to make the fuel rods for the burner reactors (per wiki).
  21. Lowbacca_1977 Jedi Master

    Member Since:
    Jun 28, 2006
    star 6
    I use wikipedia all the time as source on here. It's usually not written in tech-speak and is easier to post as a source than published papers or text books since anyone else can reach it.
  22. Darth_Yuthura Jedi Padawan

    Member Since:
    Nov 7, 2007
    star 4
    Ever hear of the internet? There are countless sources one could reference online that go beyond wikipedia. Here's one that discusses the economics of energy production and how little the cost of the fuel influences the price of nuclear energy.

    http://www.world-nuclear.org/info/inf02.html

    And reprocessing of nuclear fuel is expensive, which is why it isn't used as extensively as some would suggest. Between fast breeder reactors and reprocessing, the clear winner would be the breeder reactor. Most of the benefits related to the disposal of spent fuel rods are the same, as above 80% of the U-238 in the rod is used. This means that each reactor produces significantly less waste byproducts for any given unit of energy.

    http://www.wise-uranium.org/nfcch.html
  23. Neo-Paladin Jedi Master

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    Dec 10, 2004
    star 4
    I'm afraid the longer this goes on the more confident I am this isn't a miscommunication. While fuel cycle analysis isn't what I do (I've taken the fission classes mind you, but my MS work was done in fusion technology), I'm assure you I'm well versed in the subject from lectures, coloquia, and conversations with people who do fuel cycle analysis as their PhD topic, as well as directed reading on the subject.

    I have tried to make it abundantly clear you can't have a breeder reactor that burns spent fuel without reprocessing. I'm not sure how to make this fact more clear. You seem to be arguing one can simply take a fuel rod out of a LWR, and drop it into a breeder reactor to burn the waste. This is not the case. If you think you can burn spent fuel in a breeder reactor without reprocessing you are mistaken. This public info page makes the same point, but with pictures! The waste always goes to a "recycling" (a.k.a. reprocessing) plant before new fuel goes to a plant.

    The US absolutely stopped reprocessing in the Carter administration because of proliferation concerns. This is a matter of record; Carter said as much, point blank. Much of the resistance today is still based on proliferation concerns (see www.npolicy.org for an example). I'll concede that England's reprocessing program faces financial woes, however France, Russia, Japan, and India are going strong. The US just signed an agreement that lets India reprocess our spent fuel, interestingly enough.

    While the cost issues you raise are true (it's cheaper to get fresh uranium than uranium from spent fuel rods), as you have pointed out, the cost of uranium is a minor element in the CoE from fission power so the price differential is somewhere less than 1 cent/kWh. In my experience, researchers and industry are of the same mind on this one, reprocess the fuel, eat the cost, decrease the waste and amount of consumed uranium, and eventually (ASAP) build burner reactors to get more power from the fuel and transmute the actinides and plutonium into short lived high level waste. In point of fact, there is a federally mandated fee on fission power that goes to paying for waste disposal, which is more than the price differential in the uranium; we've effectively been eating that cost for 50+ years while waiting for the Federal government to handle the waste. That price differential drops further if we can burn the waste in a breeder reactor.

    I think our positions could be close (fast breeders burning waste is good!), were it not for one stumbling block (reprocessing is a technology that enables fast breeders burning waste). Am I right?
  24. Darth_Yuthura Jedi Padawan

    Member Since:
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    When the hell did I suggest disposing of spent LWR rods in breeder reactors? I was merely suggesting disposing of the spent rods conventionally for the time being and first transitioning to breeder reactors. Since there's an abundance of U-238 in the world today, you would use mined uranium; not spent fuel rods. If you start off by switching to breeder reactors, you can satisfy increased demand for nuclear energy without overtaxing supplies.

    To start out with reprocessing would still leave the world's supplies of uranium 235 in question. You'd reduce the sheer volume of waste, extract some unused U-235; but you'd only be able to push nuclear energy so far before supply can't meet demand. Breeder reactors are better because you can extract several times more energy than conventional reactors, greatly extending potential supplies from decades to centuries.

    Alright, I'll admit that people make too big a concern over nuclear proliferation. What people don't understand is that nuclear energy is safe, so long as it's handled properly. Most accidents and disasters in history have all resulted because they technology was abused. The only exception to this is Three Mile Island. Otherwise people should not get all worked up over nuclear proliferation or accidents UNLESS nuclear technology is not handled properly.

    You just brought up that increased demand for nuclear energy would completely overwhelm the world's supplies of uranium. I'm not so fixated on the price of uranium as to whether the world's supplies can be sustained with increased demand for nuclear energy. By no means can this be done with conventional reactors, as they can only make use of U-235. The primary advantage of breeder reactors is that they can provide a viable solution to stretching the world's supplies of nuclear fuel to sustainable levels. You could theoretically have breeder reactors supplying 100% of US electrical demands without overtaxing the world's supplies of uranium.

    That's over-simplistic, I know; but it is much more realistic than to suggest using conventional reactors and extending their fuel supplies through reprocessing. Any future with conventional reactors will hinge entirely on supplies of U-235, whereas breeder reactors can make use of a more abundant isotope.

    I'm not as focused on waste as I am on maintaining a sustainable source of energy. You probably believe I'm for breeder reactors because I consider them a means to deal with nuclear waste products... I'm not. I'm for a reactor that can use the more abundant U-238 isotope.

    EDIT: After going through one of the sites you provided, I see another potential benefit that actually takes the best of both ideas. By using b
  25. Neo-Paladin Jedi Master

    Member Since:
    Dec 10, 2004
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    OK, I understand we were talking about related, but different things.

    For what you were originally talking about Thorium is what I've typically seen as preferred fuel, for a few reasons including price as well as proliferation. I have no doubt, that if we can't get fusion off the ground, that is the way we will go.

    The conclusion I've reached is breeder reactors are like fusion: we'll have them as soon as we fund them in a manner equal requirements of the research. Of course the fusion reactors would leave the breeder reactors redundant.

    That and the fact that with reprocessing we've got enough Uranium reserves currently for something like 1000 years means industry is putting more focus on reprocessing than the rest of the closed fuel cycle, largely for waste management reasons. I should further point out that reserves aren't resources, that is there is much more Uranium out there than the current reserves, it's just not as attractive as the easy stuff or the stuff that hasn't been discovered yet.
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