8-Years of Civilization Remaining

Discussion in 'Earth Science' started by Success_Machine, Jun 7, 2002.

  1. Edufer Tired warrior Registered Senior Member

    Messages:
    791
    Cheap solar power?

    If you feel solar power is not expensive... Back in the late 70s Southern Calfornia Edison at Barstow, built a solar power station called <b>Solar One</b>. It covered 75 acres with one million square feet of computer-driven highly polished mirrors --11,818 mirrors in all-- reflecting sunlight onto a water tower 300 feet high. With some storage devices Solar One generated about <b>10 MegaWatts</b> of electricity at a cost of <b>$14,000 per installed kilowatt</b>. This was about <b>FIVE times more costly</b> than the most expensive nuclear plant.

    Solar One worked for eight hours a day on summer, four hours in winter. Assuming nothing went wrong and the 11,818 mirrors remained clean (what a task!) it means Solar One was available for power production between <b>17 and 33% of the time</b>. Nuclear plants have an availability of 65 to 90% (as our Nuke station at Embalse, in Córdoba, Argentina), In other words, Solar One produced about <b>ONE percent</b> of the electricity of a nuclear or coal-fired plant, on five times more space and is available only a quarter of the day.

    The total cost? About <b>EIGHT times more expensive</b>. Solar power is no bargain.

    Just for the record: to construct a solar plant, the following amounts of material are needed: 35,000 tons of aluminum, two million tons of concrete (500 times more than for a nuclear plant), 7,500 tons of copper, 600,000 tons of steel, 75,000 tons of glass, and 1,500 tons of chromium and titanium. Really, easily affordable for any Bolivian city...

    <b>End of the story:</b> Solar One was seriously damaged by an explosion and fire on August 31, 1986, becuase the transformers were not insulated by PCBs (the EPA had banned them). The remains were auctioned for scrap salvage at about <b>$75,000</b>. The original cost = $14,000 per installed kilowatt multiplied gives a final price of <B>$14,000,000,000</B> (14 billion dolars), net loss= <B>$13, 999,925.000</B>. Taxpayers money, of course. Want to give it another try?

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    Zoidberg, you said it, old chap. Global Warming... What, me worry? (Alfred Neuman)
     
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  3. Gifted World Wanderer Registered Senior Member

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    Fission development has been stalled by people who don't want it(gee, I wonder who). The propaganda says that breeding fuel, which is actually quite safe, is not. The publicity by greenpeace and other radical green groups as well as NIMBY have stalled the development of this resource. People don't know enough, so they turn to people who do. Unfortunately, many of these people twist the facts for thier own benefit(look at the ozone scare, global warming, there is a crapload of stuff).
     
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  5. Success_Machine Impossible? I can do that Registered Senior Member

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    blah blah blah

    I'm not saying we should go solar, but solar concentrators are less expensive than photovoltaics. I DO NOT believe that Solar One cost $14 billion. That's the entire annual budget of NASA.

    http://www.eren.doe.gov/troughnet/

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    The abiogenic theory of oil, or even the biogenic theory of oil, are irrelevant because we are using the stuff faster than it is being replenished. As time goes on it gets harder to get oil out of the wells. As such, reported reserves will last forever, but annual yields will eventually start declining, no matter how hard we try to pump more oil out. This phenomenon is called the Hubbert Peak, and has already occurred in about 50 countries around the world, including the United States and United Kingdom. Oil production in the US is down 34 percent since 1970, and continues to decline, forcing Americans to import more oil. The UK's North Sea oilfields are dropping much faster, with production peaking in 1998, and yields declining by 11 percent annually since then. By 2015 there will be no oil to speak of anywhere in the world except the Middle East. When their oilfields start to decline we're all in big trouble, if we aren't already. Many people predict, based on the estimated reserves remaining worldwide, and the behavior demonstrated by already-declining oilfields, that the world's oil supply will reach global Hubbert Peak around 2010, and drop steadily for decades after that. The oil will never run out, but supply (our ability to get oil out) will be harder, and harder, and harder to maintain. Even while supply lines are failing oil companies will still be reporting hundreds of billions of barrels of reserves, and people will be screaming for an explanation for massive increases in fuel prices. After a year or two, it will finally sink in, and I think SUVs will vanish off the streets, to be replaced initially by diesel Jettas, until people realize that they are gas hogs too, and that personal conveyances really need upwards of 200+ mpg to use renewable fuels effectively.
     
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  7. kmguru Staff Member

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    11,757
    What are you going to do at night and in UK where it is almost always cloudy?
     
  8. Edufer Tired warrior Registered Senior Member

    Messages:
    791
    Re: blah blah blah

    The figure $14 billion comes from the data given by Southern California Edison Co. that Solar one had 10 Megawatts and it installed cost per <b>kilowatt</B> was $ 14.000. Just make your own maths.

    There is a page for kids on solar power that could be interesting for you at: http://www.eia.doe.gov/kids/renewable/solar.html but I found it a little simplisitc for my taste. It says solar power is great! I doubt it. Solar power is good for just very punctual situations, where taking electricity by means of high power lines there would be too costly, like a shack in the jungle. An Honda 5 kw portable generating plant costs $600 and will work 24 hours a day. I had one in the Bolivia Amazon and it served me well.

    Some indians there (who can afford it) use solar panels with a 120 AMP truck battery for lighting their shacks with a 40 watts fluorescent tube, and a transistor radio too. It gives no power to run a refrigerator, though. So they have fridges running on kerosene or butane gas. They are good.
     
  9. Success_Machine Impossible? I can do that Registered Senior Member

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    365
    Continuous Solar Panel Manufacturing

    I am extremely interested in the idea of a solar-powered factory that manufactures solar panels, self-sustaining I assume? Do you have more information?
     
  10. Thor "Pfft, Rebel scum!" Valued Senior Member

    Messages:
    7,326
    Solar power is very unreliable. It would have to be big enough to be able to store enough power for nighttime and during cloudy days.
     
  11. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    Solar Module Factory

    Not necessarily. I'd assume that the normal work day is 8 am - 5 pm. Sometimes the sun wouldn't be shining, but if I chose a location like central Mexico, the sun would be available most of the time. Annual mean daily total global horizontal solar radiation for most of central Mexico is approximately 7 kWh per square meter, far superior to southern Ontario Canada, where I am now, and where the annual mean daily total global horizontal solar radiation is just 4 kWh per square meter. Thus by choosing the right location I could nearly double the operating hours of such a factory to produce cheap solar panels.

    I am very interested in the continuous process for producing solar cells mentioned by kmguru, I you could elaborate I'd appreciate it.
     
  12. Avatar smoking revolver Valued Senior Member

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    19,083
    A better idea would be to cover all the Sahara with solar panels.
    And Australian deserts too.
     
  13. Thor "Pfft, Rebel scum!" Valued Senior Member

    Messages:
    7,326
    Yes, but you'd have to spend money to actually send the electricity around the world. It would be too risky an investment for many companies.
     
  14. Avatar smoking revolver Valued Senior Member

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    19,083
    Well it would be OK for Australia. Deserts in the centre, all the cities by the coasts. A pefect location.

    For Sahara-> It could support the Mideterenian(sp) countries and probably more.

    Later we might have no choice but to build these enormous solar plants, wen oil runs out.
    And they are much safer for environment than nuclear plants, which are very hard to maintain.
    Solar plants
    pros: safe, don't pollute environment, infinite and free source of energy .
    cons. take up much space (with sahara it should be no problem), expensive to built, you need much of them to make them efficient.
     
  15. kmguru Staff Member

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    11,757
    First raise some serious money (a few million dollars) to build the factory. The initial money should be used to do the detail design for such a factory. Then you have to do a secondary funding from investment banks and corporations. There are three ways , one can do a continuous process - Crystal, Amorphous, Polymer. We need to do some predesign work as to the cost and production to see which one would be the cheapest to produce.
     
  16. Thor "Pfft, Rebel scum!" Valued Senior Member

    Messages:
    7,326
    Ah ha. I've just thought of a problem. With all this sand around, wouldn't they scratch the panels thus reducing its efficiency. Also, you'd spend a fortune paying people to actually polsh them every once and a while.
     
  17. Avatar smoking revolver Valued Senior Member

    Messages:
    19,083
    automatic polishers can be made. and about the sand....well you could build a nasty wind redirrection system that sweeps the sand off the panels. there are many possibilities...there even are some projects aleready (saw on discovery)
     
  18. Thor "Pfft, Rebel scum!" Valued Senior Member

    Messages:
    7,326
    This project would cost untold millions. I'd estimate at least 100million to start with and a yearly budget afterwards. Its the way forwards, but for many companies, its the way back for their wallets.
     
  19. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    Crystal amorphous, silicon

    Firstly, I know little about how to make solar panels. But I am fairly certain that you have to melt silicon dioxide which takes alot of heat. Then dip in a sacrificial carbon electrode to strip off the oxygen, which takes electricity. The resulting ingots of pure silicon must be annealed to form monocrystalline microstructure, then cut into thin wafers, and this takes heat and electricity. Then thin layers of metal are deposited on the wafers to form electrical p-n junction, followed by antireflective coatings, etc. etc.

    The factory would have to manufacture both polished metal reflectors and photovoltaic materials. It seems that you would have to start small, making raw materials and forming them into these two distinct types of solar equipment. Gradually you could expand, making sure you have a surplus to sell and cover the cost of repairs to tooling, lathes, saws, torches, welding equipment. That is until you can make that stuff too.

    The energy is free, so if you can tap into it effectively, why can't a solar module factory be self-reproducing?
     
  20. Edufer Tired warrior Registered Senior Member

    Messages:
    791
    Some forgotten facts

    Solar energy is like a child, crippled since birth. We love him, care for him, would do anything to make him happy in life. We'll spend lots of money in specialized training and fitting programs, encourage him to participate in "special people" tournaments. But deep in our hearts we know he will never get a Gold Medal in the Olympics.

    It is possible to produce electricity from sunlight if --and here is a big "<b>IF</b>" --all you need is a few watts, not kilowatts or megawatts, and only if you are willing to pay exorbitant prices for it. Solar cells are vastly used in satellites (although not for deep space probes that use small nuclear reactors). Solar cells are useful for powering sensors, repeaters, beacons, and recording devices in remote and inaccessible places. But for high demand of power as house appliances, industries, or cities, solar power <b>is not an alternative</b>. Why not? Because, to begin with, sunlight is <b>diffuse</b>. To use it as a source of electricity, you must first collect and concentrate it. Two analogies will help us to illustrate the point.

    First: suppose you wish to boil a pot of water and all you have is a bunch of matches. No matter how many millions matches you have, the water cannot be heated to boiling by holding them, one by one, under the pot. The heat applied is too diffuse. Even burning all the matches at once will not do the trick. There is simply not enough heat concentrated <b>for a long enough time</b>. Just plain physics. To achieve the required temperature, concentrated energy must be used, such as produced by igniting burning material, wood, coal, charcoal, gas or oil.

    The other analogy is the one I like most, for it dramatically illustrates the importance of <b>concentrated energy</b>. In biology there is a term, <b>"biomass"</b>, which refers to the total amount of living material in any body or collection of living things. Thus, you can compare the biomass equivalent of different species; for example, there is the same biomass in the body of <b>one elephant</b> as there is in <b>100 million fleas</b>. Now, if you need to pull a very heavy load, would you rather harness one elephant or 100 million fleas? Provided, of course, that someone builds 100 million flea harnesses at a price you can afford, and provided, of course, that you can make all those fleas hop at the same time and in the same direction.

    This explains the trouble with solar power. It is difusse and, like the fleas, is is difficult and expensive to organize and concentrate. At best --that is, at noon on a sunny day-- sunlight strikes the earth with an energy of about 1 kilowatt per square meter. There is no way to make the sun shine hotter or to collect more energy from sunlgiht, except to capture the one Kw/m2 from a <b>very large area</b>. Therefore, solar collectors are needed. You can build them with mirrors or lenses, but these must be installed with small motors -computer driven- so they can tilt and rotate and be kept in position with relation to the sun as the earth turns on its axis. And this is <b>extremely expensive</b>. Solar stations would normally cost from five to eight times more than a nuclear station with similar power output. Maintenance costs are terrible: it gives you electricity five times more expensive than nuclear.

    What about photovoltaics? They are truly high-tech, and considerable energy is requried for their manufacture, their construction also requires toxic materials from cadmium to hydrofluoric acid. This, together with the large maintenance problem involved in keeping the colletors, mirrors, lenses, and solar cells free from dust, greasy films, and snow, combines to make solar power <b>one of the least safe ways to generate electricity</b>. (Cohen, Bernard, L., 1983, "The Solar Dream", Chapter 9, in "Before It's Too Late", <i>Plenum Publishing</i>, New York). To supply the 7,000 MegaWatts required, New York City would need at least <b>350 square miles</b> of solar cells, <b>an area larger than the city itself.</b> Extend that for all cities in the US and you'll have very little space left for agriculture. Or you can build the panels on top of the cities and live forever in the shade. Does this not appeal to you? Think you'll be protected against UV rays that the Ozone Hole in Anarctica is sending to the US via Federal Express.

    So, balancing all the facts, we see that the only reasonable thing to do is going nuclear, either fission or fussion. What are we waiting for? Without doubt, today's nuclear power reactors are clean and safe, but the questions persists: Are they safe enough? How safe is safe enough"? How is safety judged? And by whom? If engineered safety --that is, multiple, redundant backup systems or "defense in depth"-- is safe, how much enhancement is needed? How much is wanted? Or warranted? At what point the cost of yet another marginal increment in safety be considered?

    It is interesting to note that in our society, $200,000 is spent annually on safety improvements to save a single life in a car accident --where 50,000 deaths occurr each year. But in the nuclear industry $2 billion is spent yearly <b>to save one life, even though there have been no fatalities.</b> What else do we need to start building nuclear stations again?
     
  21. wet1 Wanderer Registered Senior Member

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    8,616
    Something else needs to be mentioned in this about solar cells that I have not seen mentioned. The output of these cells is in DC (direct current). To store this electricity you must use batteries. Wet cells. Now you can use the standard car battery but it is not very effecient. Futher the deep charging that is required for the batteries means that the normal wet battery will not last very long before needing replacement. Most sites that use solar cells store in cadium cells. This because the cadium cells last longer with the deep charge/discharge requirement. They are considerably larger and more expensive than the standard battery. I won't go into the disposal methods for hazardous substances within.
     
  22. kmguru Staff Member

    Messages:
    11,757
    Nickel metalhydride is a better alternative. While cycle life is said to be similar, in practice, Ni-MH lasts longer than Ni-Cd

    Advantages of the Nickel-Metal Hydride Cell

    The three major benefits of the nickel-metal hydride cells to designers of portable electrical and electronic products are:

    1. Improved energy density (up to 40 percent greater than nickel-cadmium cells) which can be translated into either longer run times from existing batteries or reductions in the space necessary for the battery.

    2. Elimination of the constraints on cell manufacture, usage, and disposal imposed because of concerns over cadmium toxicity.

    3. Simplified incorporation into products currently using nickel cadmium cells because of the many design similarities between the two chemistries.


    More...
     
  23. kmguru Staff Member

    Messages:
    11,757
    Re: Some forgotten facts

    That is perhaps because, 99.9% people do not understand what is nuclear powerplant. They all equate nuclear with Hirosima or nuclear bomb in their mind. So even educated people and people who have taken physics still say - "ya, but..." to anything one says on nuclear.

    That is human nature for you. Our earth is powered by a nuclear generator to create the magnetic field that protects us all.

    Anyway, Nuclear to electricity is the way to go. If I have the time and can get a permit, I am sure I can design a major power system that does not use steam turbines to generate power.

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