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Nuclear Power: Yay or Nay? watch

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  • View Poll Results: Nuclear Power: Yay or Nay?
    Yay!
    45
    73.77%
    Okay...
    10
    16.39%
    Nay!
    5
    8.20%
    Eh?
    1
    1.64%

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    (Original post by Jonatan)
    News flash ... do tell me, because I sure haven't heard about it despite following this debate quite thoroughly.
    That's pretty impressive for a drunk :five:
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    (Original post by Jonatan)
    News flash, physics is NOT commons sense, it is in fact rather complicated ( which is why you need to study a bit to get a degree in it ). I'm a little to drunk at the moment to argue my point in detail, but suffice to say is that Germany's policy of decommissioning their perfectly usable reactors ( which cost them quite a bit to build I might add ) is absolutely utterly insane, and it is based on pure political populism rather than real science.
    yes it is. But is that a bad thing? its similar to the argument that beholds the wonders of the free market...perhaps in a model but this is the real world where people are involved....so common sense in the scientific world is perhaps not the best option in the real world.

    (Original post by Jonatan)
    De-centralised power productions sounds like a beautiful romantic goal, until you realise that small-scale wind turbines and solar panels are really rather ****, compared to the larger versions.
    Again can't quite understand what you mean. I'm not advocating which is best or more efficient....just that if you combine a number of small scale units you can geneate the same level of energy as a larger unit.


    (Original post by Jonatan)
    No, really, if you are absolutely going to go for wind power ( even thou it has a variable power output, unstable and unpredictable supply, high price as per kwh, and a range of other problems )
    I think you will find that when you assess the data the kWh price for wind in the UK is artificially inflated by governemnt policy, and if left to its own devices would fall dramaticially over the next few years just like it has done in Germany.

    (Original post by Jonatan)
    As for solar. Well, solar heating has some niche application (like in satellites where you don't want to go refuel a power plant ),
    50% of domestic heat for a dwelling in the UK in winter is achievable from a solar water heating system, so its application is quite handy, when combined with other sources such as ground source heat pumps.

    (Original post by Jonatan)
    but photo-voltaic for electricity generation is easily described with 4 letters c-r-a-p. Even at 100% efficiency ( which is physically impossible anyway, but never mind that ) a solar cell cannot output more energy than comes in to begin with, and this depends on the climate and weather. It can sort of work for some applications in Germany (thou wind power would produce more energy for the same price ), but for a country with England's climate it is simply a moronic idea. To deploy an electricity generation scheme with an output dependant on sunlight in a country famous for fog and rainfall is quite simply bad bad idea. Heck, in either case, if you wanted to use renewable energy sources, solar power is so expensive (as calculated in life-cycle costs) that you are better of using wind-power anyway.
    Actually when factored into eco design buildings a photovoltaic arary can provide around 30% of the electricity needs of a building. In the UK climate they obviously don't currently work to their full potential. However they cost is falling not as low as wind or other forms of alternative energy yet but in about 10 years time (give or take) it will be more competative.

    (Original post by Jonatan)
    I'm fairly convinced judging from how you usually argue when this topic is brought up, that your opinion is more based on political ideology (i.e big centralised companies are evil, small individual generation is good ) than actual consideration of the feasibility of what you advocate.
    Yes it probably is....that fact that the golbal energy market is dominated by less than 10 companies is a disturbuing thought. why should i not be allowed to put capacity into the system an be paid a fair price for it? Thats what happens in the local system.

    (Original post by Jonatan)
    Incidentally there is one case where de-centralised generation can improve efficiency, and this is with de-centralised FOSSIL FUEL burner. The reason for this is that a fossil fuel generating plant wastes quite a bit of it's energy output as heat, but if you have it de-centralised you can use that heat to keep your house warm in district heating schemes.
    Yes I know! its called cofiring/chp and often involves a stirling engine. By the way its used a little in scandanavia to good effect. Also they tend not to use fossil fuel but rather renewable sources, such as biomass, also crap burns well.

    (Original post by Jonatan)
    But please, let me hear why centralised power production "makes no common sense". After posting here for almost half a year the best you have come up with is "it is less efficient" which quite simply isn't true for reasons I have outlined above. Really, if you know of any counter-intuitive reason why small-scale generation is more efficient, beyond the small amount of energy lost in the power grid, do tell me, because I sure haven't heard about it despite following this debate quite thoroughly.
    It is more efficent in terms of cost, the environment and society (argued by Pasqualiti not me) also it happens to be sustainable, unlike nuclear power. I don't deny that nuclear has the potential to supply the UK with power it clearly does, perhaps at current it is more cost effective than alternative forms of energy, but as i argued above what makes science sense is not common sense.
    It does make me wonder why build new nuclear capacity, the argument about global warming makes some sense....however the concept of nuclear being the answer???especially when any new stations will be built on the coast. where is the logic in that? Have you factored in the cost of sea defences per KWh i doubt it.
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    (Original post by ali567149)
    By the way its used a little in scandanavia to good effect. Also they tend not to use fossil fuel but rather renewable sources, such as biomass, also crap burns well.
    Bull****, I'm born in Sweden and live in Norway. Norway produces virtually all it's electricity by damming up rivers for hydroelectrics, thus destroying vast areas of land behind the dam. Sweden produces virtually all its electricity from similar plants and Nuclear. The only Scandinavian country to use a decent amount of alternative energy sources is Denmark, and even they only produce 18% of their electricity using wind turbines with a huge fraction of the remainder being produced by coal fired fossil fuel plants. Basically, with the exception of Denmark's wind turbines and Sweden's Nuclear power plants, most of the Scandinavian electricity comes from either fossil fuels or hydro, both of which have sever environmental impacts.
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    (Original post by ali567149)
    Actually when factored into eco design buildings a photovoltaic arary can provide around 30% of the electricity needs of a building.
    Let's have a look at that claim. Annual average insolation in England is roughly 250 watts per square metre. Solar cell energy conversion efficiencies are around 14-16% for commercially available cells, giving a high estimate of 40w per square metre.

    So basically, your figure can only be correct for a house so well insulated that it requires practically no heating, in which case it would also require very little electricity. Your claim would therefore not show solar panels to have any great potential, it would merely show that it is possible to build very well insulated houses, but that is true no matter how you heat them , be it with solar or electricity from a nuclear power plant. So you could try to install literately millions of square metres of solar panels ( giving 40Mw of electricity at best ) and you would still be a factor 100 or so bellow the energy generated by a single nuclear power station ( a large nuclear power station can produce gigawatts of electricity).

    Of course, the solar panels have the slight disadvantage that they don't work during the night, and produce significantly lower energy output when it is cloudy ( and no, even solar cells that can use the little light that is around when it is cloudy can't produce more electricity than incoming light ).
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    (Original post by ali567149)
    I think you will find that when you assess the data the kWh price for wind in the UK is artificially inflated by governemnt policy, and if left to its own devices would fall dramaticially over the next few years just like it has done in Germany.
    Nonsense. Germany heavily subsidise wind turbines through tax credits and by capping the price of wind turbine sales ( which effectively means the tax payer pays the bill ). If left on its own the price would thus almost certainly rise.
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    (Original post by ali567149)
    It does make me wonder why build new nuclear capacity, the argument about global warming makes some sense....however the concept of nuclear being the answer???especially when any new stations will be built on the coast. where is the logic in that? Have you factored in the cost of sea defences per KWh i doubt it.
    Well, let me see...

    a) It can ensure not only current energy demand but any future rise as well, including any measures we need to replace other technologies ( replacing petroleum with electric trains and cars etc ... )

    b)It is clean ( no, really )

    c)It doesn't require the destruction of large areas of land or forest.

    d)The power output is controllable and stable, so it can be tuend according to demand.

    e)There is no dependence on local weather o climate conditions.

    f)It is cheap. I refer you to the royal academy of engineering's report as well as MITs report on the prices of different forms of energy generation (both reports assumed 0 subsidies )

    g)There is no dependence on the political stability of foreign powers.

    h)The technology is already proven and known to be sustainable for at least several thousand years.

    As for the sea defences bit, you are clutching at straws now, if sea levels rise to that extent you are basically talking about entire cities ( or even countries ) being submerged, so heaven knows what economics will be like in that case. Preventing sea level rise by limiting emissions is the only way to go, and if sea level rise increases to that extent then the cost of electricity generation really is the least of our concerns. I'd be more worried about multi-million people cities suddenly becoming uninhabitable.
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    I'm assuming nuclear reactors have to be quite big, which is why we can get them onto submarines but not into smaller forms of transport such as cars or trains? Aside from the safety implications, I guess. What about planes?
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    (Original post by Jonatan)
    Not quite as simple I'm afraid. The stuff we dig out of the ground is mainly Uranium-238 which has a very long half life ( and is thus only moderately radioactive ). In comparison some of the actinides have half lives of "only" a few thousand years, meaning they will be significantly mroe radioactive than uranium for several millennia. The reason this is NOT a problem is that they compose a fairly low proportion of the spent fuel, and also because they are heavy atoms which can be recycled as nuclear fuels ( thus resulting in waste which decays to safe levels much quicker ). So while it is true that the half life is directly linked to the radioactivity, you need to specify that very little of the waste has intermediate half-lives. I.e, it is more like this:

    short half lives: good
    medium half lives: bad
    long half-lives: good

    I.e, the stuff with short half lives decays quickly and thus isn't a problem. The stuff with long half-lives isn't much more radioactive than the ground itself, and is thus not a problem, but the things with intermediate half-lives is both radioactive enough to be a problem, and long lived enough that it is difficult to store. It is a fortunate coincidence that the fission products belong to either the very short lived or very long lived isotopes, and thus the waste problem is solvable. Had the fission products had half-lives in the regime of 5000-20000 years nuclear waste would be a major problem, but fortunately virtually all of them have half lives which are either less than 30 years or more than 100.000 years, and thus the issue can be solved by using the actinides ( that have intermediate half-lives ) as nuclear fuels, producing only fission products as waste.
    The reason I was so simplistic was because I'm tired of hearing "waaaah we're putting things in the ground that are harmful for thousands of years, we can't do that" when in reality, the methods of handling waste are well established, based on sound physics and effective.

    To me, as you have just outlined, the waste argument is a non-issue.
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    (Original post by Mad Vlad)
    That's pretty impressive for a drunk :five:
    Mad Vlad, why don't you put your comments in this thread and discuss them with me rather than neg repping me?

    (Original post by Mad Vlad)
    You're just not listening are you? You're so set in your ways that nuclear power is the root of all evil, you can't see past the end of your nose at the overwhelming evidence being presented to you to the contrary.
    I am not closed minded and am perfectly willing to listen to Jonatan and others about the benefits of nuclear power.

    You've reduced my number of green blocks down to five now.
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    unless they've somehow lowered down the potential risk of living in a nuclear power station area. and found out a way for disposing nuclear waste safely. why don't they shoot tins of them into outer space? :ninja:
    when all risks are cleared (which i doubt it anyway :proud:) then yes, nuclear energy rocks ;yes;
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    Okay.
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    (Original post by Agent Smith)
    I'm assuming nuclear reactors have to be quite big, which is why we can get them onto submarines but not into smaller forms of transport such as cars or trains? Aside from the safety implications, I guess. What about planes?
    Nuclear reactors can be made fairly small, probably small enough to fit in a car. The problem is that nuclear power is not that great at rapidly changing its power output. This is done by raising and lowering of control rods which presumably are not fast enough for the power variation in a car (i.e very rapid increases and decreases).

    Also, nuclear reactors produce energy in the form of heat. But not in an explosive reaction which drives an internal combustion engine. If you raise power output of a reactor then you would also have to wait for the steam or whatever your coolant is to respond to these changes, making output even slower to change.

    Also nuclear reactors need shielding, which is going to add considerbly to volume and weight. Not very efficient for small, light vehicles such as cars. Not such a problem for a submarine which is far heavier.

    There is also the problem of turning off, a nuclear reactors can't really be stopped. It needs to be run continously and therefore cooled continuously, which isn't very good for a car where you need to turn it off regularly.

    Planes would suffer the same problems as a car except weight would be even more of in issue, also whilst its possible to power a car through steam it is not possible to produce "jet-like" thrust from steam power. you could pottentially use it to drive a propellor though.
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    (Original post by Zebedee)
    Nuclear reactors can be made fairly small, probably small enough to fit in a car. The problem is that nuclear power is not that great at rapidly changing its power output. This is done by raising and lowering of control rods which presumably are not fast enough for the power variation in a car (i.e very rapid increases and decreases).

    Also, nuclear reactors produce energy in the form of heat. But not in an explosive reaction which drives an internal combustion engine. If you raise power output of a reactor then you would also have to wait for the steam or whatever your coolant is to respond to these changes, making output even slower to change.
    Good point.
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    I love nuclear.
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    (Original post by Chezua)
    unless they've somehow lowered down the potential risk of living in a nuclear power station area. and found out a way for disposing nuclear waste safely. why don't they shoot tins of them into outer space?
    The risks associated with sending Nuclear waste into space would be orders of magnitude greater than simply keeping it stored in a safeguarded building. It would also be much more expensive seeing that nuclear waste is rather heavy ( Uranium weighs almost 20 ton per cubic metre ) and is thus rather tricky to lift with a rocket.

    Oh, and the risks associated with living next to a power station are much smaller than those associated with living next to a road. You're more likely to get run over by some drunk idiot than suffer any ill effects from a nuclear power station. In fact, if your city has a nuclear power station the air quality is likely to be a lot better than for cities that get their power from coal, so your overall risk of getting sick , everything else held constant, should be lower.
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    (Original post by Zebedee)

    There is also the problem of turning off, a nuclear reactors can't really be stopped. It needs to be run continously and therefore cooled continuously, which isn't very good for a car where you need to turn it off regularly.
    This is not completely true. You can stop the chain reaction very rapidly ( within seconds ) and the power output will drop rapidly after that. However, about 10% of the heat output is due to the radioactive waste generated in the fuel rods, which explains why a reactor needs to be cooled even after it has been shut down.

    The main reason why nuclear plants are not shut down very often is that safety regulations require that you allow the radioactive Xenon to decay before trying to restart it again. When you turn off a reactor a lot of neutron absorbing Xenon is generated and this makes it difficult to predict the appropriate control rod settings to start the reactor again. Therefore standard safety procedure requires you wait for a few hours so the Xenon can decay away. At Chernobyl the operators were in a rush to carry out a safety test ( under military orders ) and thus ignored this safety rule. This together with the reactor's unstable design is thought to be the main cause of the accident ( actually there were 2-3 other contributing problems as well, but they are a bit off topic ).

    Also, when it comes to airplanes, you can produce quite a bit of thrust using a nuclear reactor. Power plants use turbines not too different from a jet-engine in order to convert heat into electricity. Would still be rather silly to make a nuclear powered air plane, but it didn't stop the American military from trying to develop a nuclear powered bomber for their atomic weapons. The project was eventually scrapped, partially because long range inter-continental ballistic missiles would be far more effective. There were also plans to build nuclear powered cars ( they would work a bit like hybrids. The reactor produces electricity to charge a battery, which in turn drives the wheels ). Needless to say having every single motorist own a nuclear reactor would be a bit of a proliferation concern, so nuclear powered cars were never licensed.
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    (Original post by Zoecb)
    Definitely - it's renewable energy, but does provide employment (wind turbines and things are better obviously, but they do kinda mostly look after themselves).
    I agree what what you've said there, as long as it is controlled and there are high levels of security enforced. Nobody wants another Chernobyl.
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    (Original post by Jonatan)
    The risks associated with sending Nuclear waste into space would be orders of magnitude greater than simply keeping it stored in a safeguarded building. It would also be much more expensive seeing that nuclear waste is rather heavy ( Uranium weighs almost 20 ton per cubic metre ) and is thus rather tricky to lift with a rocket.

    Oh, and the risks associated with living next to a power station are much smaller than those associated with living next to a road. You're more likely to get run over by some drunk idiot than suffer any ill effects from a nuclear power station. In fact, if your city has a nuclear power station the air quality is likely to be a lot better than for cities that get their power from coal, so your overall risk of getting sick , everything else held constant, should be lower.
    oh 0_o right. i was thinking of chernobyl.
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    (Original post by Chezua)
    oh 0_o right. i was thinking of chernobyl.
    Well, even if a western power station would blow up you wouldn't get a chernobyl, because over here it is customary to enclose the entire plant in a very solid concrete structure ( this is the big dome's you can see at nuclear powerstations ). At chernobyl the initial plans included one of tehse but the Soviet government never paid to have one built because they thought it was too expensice. A bit of a pity since the accident has ended up costing orders of magnitude more, and killed a number of people. In comparison, Three Mile Island ( which was an accident of similar magnitude ) there was no damage outside the power plant because the concrete structure withheld virtually all the radioactivity and only a very small amount of radioactive gas was released. The highest radiation dose to a human in the area would have been about the same as a hospital X-ray scan.

    Of course, modern reactors are also a lot less likely to blow up in the first place, but even if they did there would be little damage to the environment or people living nearby.
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    (Original post by Jonatan)
    Let's have a look at that claim. Annual average insolation in England is roughly 250 watts per square metre. Solar cell energy conversion efficiencies are around 14-16% for commercially available cells, giving a high estimate of 40w per square metre.

    So basically, your figure can only be correct for a house so well insulated that it requires practically no heating, in which case it would also require very little electricity. Your claim would therefore not show solar panels to have any great potential, it would merely show that it is possible to build very well insulated houses, but that is true no matter how you heat them , be it with solar or electricity from a nuclear power plant. So you could try to install literately millions of square metres of solar panels ( giving 40Mw of electricity at best ) and you would still be a factor 100 or so bellow the energy generated by a single nuclear power station ( a large nuclear power station can produce gigawatts of electricity).
    Right....and do you not draw from that the concept that if we build houses to an appropiate standard thus in theory reducing demand for space heating, alternative technology is the solution.
    I would not dream of introducing new alternative technology into a home unless the insulation is up to scratch it simply does not make sense. So its a combination of policies like that advocated by the government to reduce demand for space heating. Why pay for nuclear to generate power that is wasted at the point of use, when insulation can be factored into planning law?

    (Original post by Jonatan)
    Of course, the solar panels have the slight disadvantage that they don't work during the night, and produce significantly lower energy output when it is cloudy ( and no, even solar cells that can use the little light that is around when it is cloudy can't produce more electricity than incoming light ).
    You would think that people would start to develop photovoltaics that generate electricity from a broader range of light. Well news flash they are, so how light it is to the human eye would be irelevent as the larger infrared spectrum of light is not reflected by clouds.
 
 
 
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