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Fusion power, economics

  1. Jun 16, 2016 #51

    russ_watters

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    I don't agree with any of those statements. The complexity of power grids makes them less vulnerable and more reliable than local power generation because there are multiple pathways for the power to get from one place to another. More, local power plants means more failure points with less back-up and distributed risk (smaller but much more frequent accidents).

    We have the grid that we have for real reasons; it didn't happen by accident.
     
  2. Jun 16, 2016 #52

    mfb

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    In general, larger power plants are also more efficient, cheaper and cleaner. A 1 GW coal power plant produces more electricity per coal than a 1 MW coal power plant, does not require 1000 times the manpower to operate, can afford better filtering of its emissions, and so on. Photovoltaics is probably the only thing where the scaling effects are not that significant.
     
  3. Jun 16, 2016 #53

    Ryan_m_b

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    Correct me if I'm wrong but it seems like another advantage of a grid, especially a large continental one, is so that things like PV can be used to power places where it would be less efficient.
     
  4. Jun 16, 2016 #54

    mfb

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    Yes, but I don't see how that is related to my post.

    Building ten 1 MW photovoltaics power plants is not much more expensive than building one 10 MW power plant - the bigger plant is mainly just the same thing 10 times next to each other. That is the scaling I was talking about.
    Building ten 100 MW nuclear power plants is much more expensive than building one 1 GW power plant.
     
  5. Jun 16, 2016 #55

    russ_watters

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    Solar is a bit of an odd duck on this issue. It is very unreliable (second only to wind) and as a result is almost always grid connected. I'm not sure about the economics of local vs centralized because the economics are so heavily manipulated and therefore they aren't really real (in addition to being not well publicized and being variable). The main benefit I see on grid vs distributed for solar is that buildings have roofs, which are somewhat wasted real-estate. .

    [edit: Looks like I went to a different level of "local" than mfb was referring to]
     
  6. Jun 23, 2016 #56
    With all due respect, and I readily acknowledge that you have earned respect, the North American power grid is in grim shape. It is a hodgepodge collection of independent utilities with risks associated with command, control, and communication, aging infrastructure, and growing demand. The initial ideas that were the foundation for the grid were from Edison's time. The lack of adequate network security has been documented widely. I'm sorry, but I don't see how a fragmented, aging system such as the power grid can be considered robust. You make good points regarding the ability to switch loads to deal with outages, however, the record shows that brown-outs and black-outs are becoming quite common, and they are lasting longer. I don't think that the benefits of networking such as those we see in the internet are mirrored in the power grid although efforts are ongoing to emulate that kind of redundancy.
     
  7. Jun 24, 2016 #57

    Evo

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    You say this is all documented widely, yet you failed to post this documentation, please post the sources. Thank you.
     
  8. Jun 24, 2016 #58
    Last edited by a moderator: May 8, 2017
  9. Jun 24, 2016 #59

    Evo

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    Sorry, I forgot to say that you need to also quote the pertinent parts (be careful not to violate copyright laws by quoting too much) as you cannot expect people to read an entire article and try to figure out which part you are referring to. Please quote the pertinent parts. Please be sure that they are current. And just two will be fine. Thank you.

    For example

    ]http://energy.gov/articles/top-9-things-you-didnt-know-about-americas-power-grid
    https://www.smartgrid.gov/
     
    Last edited by a moderator: May 8, 2017
  10. Jun 24, 2016 #60

    dlgoff

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    Something must be working. How do you think over 1100 Gigawatts of energy are getting transported?
    image compliments of http://www.tsp-data-portal.org
    installedpower.jpg
     
  11. Jun 24, 2016 #61

    mfb

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    The European one works nicely, blackouts are rare and usually limited to local regions for local reasons (e. g. ice or heavy snow taking down the power lines going to some town). And one counterexample is sufficient to refute the claim that "Large, continental power grids are far too complex and vulnerable".

    The largest blackout happened in 2003, affecting 56 million people - for three hours in the middle of the night. Uhh, scary. A small fraction of the population got power a bit later than the others.
    The second largest blackout happened in 2006, with 15 millions without electricity for 2 hours.

    Going by Wikipedia articles, London 2003 is the last European one that has its own article - 500,000 people for 30 minutes to 2 hours.

    The longest blackout I personally experienced in my life was about 5 minutes long.
     
  12. Jun 24, 2016 #62
    For what it is worth I heard In a news report some time ago that the US power grid is very vulnerable to severe Sunspot activity and in particular the present type of transformers that are used. Apparently there are new types that would withstand such an event. The problem being that there would not be enough spares on hand to replace the damaged one and the lead time for the manufacture of replacement transformers is 6 months. It is just another example of a neglected infrastructure issue. IMO the maintenance of the power grid is akin the the repair of highways be filling the pot holes.
     
  13. Jun 24, 2016 #63
    Periodic blackout in the US are quite common due to storms, but these are typically localized affecting only a part of a state or two but sometimes will last many days. I expect several power outages in my are of Maryland several times a year lasting up to about 12 hrs. but usually only a few hours.

    However the power grid in the northeast has been compromised significantly twice in the last 50 years.

    In 1965 much of the northeast of the US and parts of Canada lost power for over 12 hrs due to a maintenance error. https://en.wikipedia.org/wiki/Northeast_blackout_of_1965

    In 1977 New York City lightning took down the cities grid for almost 24 hrs, before totally restored.
    https://en.wikipedia.org/wiki/New_York_City_blackout_of_1977. During this time there was significant civil disobedience.

    In 2003 a computer "bug" took down the grid of the northeast of the US and Canada affecting 10's milliions of persons .https://en.wikipedia.org/wiki/Northeast_blackout_of_2003 with some remote areas being 2 weeks without power

    The European power grid is newer than much of the US because it has been rebuilt since WWII.
     
  14. Jun 24, 2016 #64

    mheslep

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    Last edited: Jun 24, 2016
  15. Jun 24, 2016 #65

    mheslep

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  16. Nov 29, 2017 #66
    Except for the end game cost where you have massive amounts of useless fission byproducts that have to be sequestered for thousands of years.
    Take that into consideration in your calculus.
     
  17. Nov 29, 2017 #67

    russ_watters

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    I do; that is a very small cost that is already priced into the cost of fission energy....though I think that charge was temporarily suspended by the courts due to the government's violation of their end of the contract (building the facility).

    By coincidence, that cost is nearly equal to what we spend on fusion research.
     
  18. Nov 29, 2017 #68

    mheslep

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    The dangerous fission products decay to below the radioactivity of uranium ore in ~500 yrs. The transuranic, non-fission products, like Pu, created in reactors have much longer half-lives, though they are alpha emitters with much lower specific radioactivity than the fission products.
    activityhlw.gif

    The heavy metal waste in, say, solar panels never disintegrates.
     
  19. Nov 30, 2017 #69

    mfb

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    3000 years going by your graph.

    Am-241 is useful as alpha emitter, if you separate it to use it elsewhere the waste falls below the level of uranium ore much faster. A factor 1000 for Sr/Cs needs about 300 years.
     
  20. Dec 4, 2017 #70

    mheslep

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    Yes, but not a fission product. Am-241 is a transuranic produced by neutron capture and decay from other transuranics, an important difference as some of the Gen IV designs would significantly burn their transuranics. An alpha emitter with low penetration power, it is dangerous when inhaled or ingested. I'd rather have some grams of Am-241 buried in my backyard (or micrograms in my smoke detector) rather than some tons of heavy metal laden coal waste.
     
  21. Dec 4, 2017 #71

    mfb

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    Fine, technically correct... still waste of current reactors (unless used elsewhere) and the most important nuclide between a few hundred and a few thousand years.
     
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