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Can Solar Replace Oil?

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  1. Aug 13, 2017 at 8:45 AM #1
    is solar even viable way to replace oil? using just the current US joules consumption and the existing solar technology, is it possible to switch to solar if oil will run dry in say 50yrs from now?

    solar technology seems to be approaching some theoretical limits, somewhere around 30% efficiency.

    i had calculated we need roughly 100k mi2 of panels, but with parallel teams to build a unit(1mi2) it will take ~500-1,000 years just to install it, and that alone is only if millions and millions of panels were sitting ready for use. simply manufacturing that many panels would take a very long time.

    so is solar a energy source worth pursuing if you cannot deploy or make panels fast enough?

    what other oil replacements is more attractive? how about nuke plants to split water to get H? is that better or worse than the solar problem? what about geo thermal, plenty of free energy there?
     
  2. jcsd
  3. Aug 13, 2017 at 9:04 AM #2

    sophiecentaur

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    Fast enough for what? The 'running dry' time for oil has been estimated at between 20 and 40 years ever since I was first aware of such things (1960s). Same as the 'batteries being good enough' time has always been a bit over ten years. Beware of quoting timescales - even when it involves decorating the front of your house±!
    The climate change problem is with us now (except in the Whitehouse and in Lord Lawson's house). With very little actual effort, the western democracies have been steadily increasing the proportion of sustainable energy being used.
    What does your 30% efficiency actually mean? It means that you need around three times more area of PV collectors and that's all.
    Thermal solar energy has not been developed much, yet and a high proportion of non-transport energy is actually in heating.
    Then there's always the gritty subject of just using LESS energy. Homes are extremely wasteful in their use of 'fuels'. Even on the enlightened PF, people talk of heating and cooling demands, rather than of insulation and reducing waste.
    One (other) thing that worries me is the catch 22 situation regarding energy use. We, in the prosperous nations could all reduce our consumption consumer goods but the effect of that would be surely to reduce growth and prosperity. Can you actually imagine anyone voting for that strategy?
     
  4. Aug 13, 2017 at 9:07 AM #3
    if you wanted to deploy solar panels to replace the energy used by the US before oil runs dry, thats the "how fast" problem. i am not asking about alternative methods like conservation, etc.

    could you even deploy them in a timely manner to be in place before oil runs dry ??

    if we cannot make and deploy solar panels fast enough then why would we attempt to do so ?

    i figured 100kmi2 based on a 7hr sunlight day w/ no clouds ever.
     
  5. Aug 13, 2017 at 9:16 AM #4

    phinds

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    Yes, and you have made a baseless claim that it will run dry in 50 years and then based your question on that baseless proposition.
     
  6. Aug 13, 2017 at 9:28 AM #5
    50yrs is arbitrary. take a snapshot of today, continue that as-is, how long will oil be available. certainly less than 100, yes?

    deploying 100kmi2 is many factors of 10 in units of years more vs how long crude will last.
     
  7. Aug 13, 2017 at 9:52 AM #6

    sophiecentaur

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    But you need to. It will be the whole situation that counts and there is no point insisting on just considering one variable. Any estimate you might make will have a huge +- involved and the other potential strategies and constraints are at least as significant.
     
  8. Aug 13, 2017 at 10:45 AM #7
    Hi Kid:

    The rate at which solar panels are manufactured is increasing, and the cost decreasing. Therefore I suggest not getting hung up on current production numbers.

    Regarding your primary question, I would answer: Up to a point, yes. However, there is no current technology to directly use solar energy as a source where one needs a small volume to hold a lot of energy, for example to fly an airplane. However, in principle solar energy could be used to create some kind of oil-like compound as a substitute. To determine the significance of air travel on the need to develop technology to use solar to generate an oil-like substitute, you can start by calculating the fraction of current oil production used for air travel.

    Regards,
    Buzz
     
  9. Aug 13, 2017 at 11:35 AM #8
    but conservation has been preached for years and look how that has worked out, fail.

    forget what oil is used for, can anyone stand-up enough solar farms before oil runs dry to substitute most of the yearly joules used by the US ?? if so how? some rough numbers is what i would like to see.

    and to note, i used gross overboard panels/day # to calculate the millions of panels needed, which turns out to be thousands of years to make. so how would anyone ramp up production to meet that need??
     
  10. Aug 13, 2017 at 11:53 AM #9

    phinds

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    Seriously ? You seem to insist on talking about something but just ignoring major factors about it. Forget what it's used for, forget conservation, ???
     
  11. Aug 13, 2017 at 11:57 AM #10

    Bandersnatch

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    The calculations you posted in the other thread (now deleted for one reason or another) were based on what is colloquially called 'assumptions pulled out of one's behind'. Why that many panels installed per day? Why not 10000 times more? Why not 1/100?
    In addition to that, why were you calculating to replace primary power and not electricity production? Why were you assuming all current energy demand in the US is covered by oil, and thus needs to be replaced?
    You did not give any reasoning for your assumptions, did not show how these follow from current yearly installed power and predicted market growth, etc.

    In short, it's hard to take your wild guesses at face value and then try to answer why they show silly things. A discussion should be (and is indeed required by PF rules to be) based on published facts, not one's own ideas on how the world works.
    Please, link to sources supporting your claims, so that we know what we're discussing.


    If you want to know if solar can replace oil, why not look at real-world examples, e.g. Germany? They have an ambitious plan to produce 80% of its electricity needs from renewables by 2050. This will include a third coming from photovoltaics. So I guess at least they think its doable.
     
  12. Aug 13, 2017 at 11:59 AM #11

    Drakkith

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    I don't see why not. Oil isn't going to suddenly run dry with little warning one day. We'll know it's coming for years. That gives us time to ramp up production of panels and other methods of solar energy collection (solar panels aren't the only solar option).
     
  13. Aug 13, 2017 at 8:09 PM #12
    Your opening post is very confusing, and totally lacking in specifics and references. You can't get meaningful answers unless the question is clear.

    Can solar replace oil? I don't see how. Oil is used not only as fuel, but to make plastics, lubricants, fabrics, etc.

    Are you talking about energy? Which energy? Most people think in terms of solar producing electricity, but oil is used to power our cars (yes, could be done with electricity), and airplanes (not likely to be powered by electricity) - not much oil is used to produce electricity (NG is, but that's not oil).

    " forget what oil is used for, "? How can we do that and answer your question? This isn't making any more sense than your posts on using Hydrogen as a source of energy.

    So, what are you talking about?

    I think I can provide some insights, but I'm not sure where this is going.
     
  14. Aug 13, 2017 at 10:28 PM #13
    its a simple question. the US uses ~25k TWh in one year. kWh is 3.6MJ
    lets says 80% of that is from oil, and oil runs dry 100yrs from now

    so now show me any numbers that shows how many solar panels it will take to match that 80% based on 7hr/day sunlight.

    put up some numbers, show some math, what do you get?

    my initial math showed we need ~100kmi2 worth of 1st Solar Series4 ~30% panels. you need millions of panels per mi2
    so two problems, even if you had all the panels stacked in a warehouse ready for use, how long does it take to deploy them into a operational system that can supply the joules? and, the existing warehouse stock of panels is relatively low, so how long does it take just to make all the panels, can panel production scale in any meaningful way to manufacture such total required panels?

    and, you'll need a boat load of input energy to make panels and install them, so must account for where this energy comes from, etc.

    yeah, i saw the selective banning of my posts, nice that PF is no longer a open place to discuss things, whether you like it or not.
    "why not 10,000 times more?", i dunno, why dont you tell me why 10k more per day is viable. i already provided the math based on real numbers, you have posted nothing.

    you do understand that the current yearly installed panel rate has absolutely nothing, nada, zip, to do with production capacity, right ?? same goes for the NRG 47GW claim, means nothing unless you deliver and bill it. a solar plant may max out at (EXAMPLE GIVEN) 20k panels per week when run 100% duty cycle @ full capacity, but that means nothing if yearly install is less than that, etc.

    if you scale that max capacity how do you do it, how long does it take to scale, how much can you scale to?

    if this basic question cannot be easily answered then thats a clear sign solar to replace 80% of US energy consumption is really not a viable solution.

    you think my claim is crap and false data, then put up your numbers. the # of panels required is very large, so large i cant see any production being able to make all of them in a timely manner. i even used theoretical 30%max panel efficiency, which is well above what is being made today! i also used a 50yr # for when oil dies, it may not be accurate, but it doesnt really matter, choose 200yrs, doesnt matter, you cannot make and install enough solar panels in that timeframe to replace the oil energy.



    you think this is wrong, then show me!
     
    Last edited: Aug 13, 2017 at 11:19 PM
  15. Aug 14, 2017 at 2:27 AM #14

    Drakkith

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    Thread locked for moderation.
     
  16. Aug 14, 2017 at 12:38 PM #15

    Drakkith

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    Due to multiple violations of PF Terms and Rules by the OP, this thread will remain locked.
     
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