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Nextgen SSOlar, Efficiency, Broadcast Power

  1. Jul 19, 2011 #1
    Would the efficiency gained in an orbital Solar generating facility be mitigated by some/degree of diffusion loss when transmitting, say by microwave. through an atmosphere?
    Is the rate of efficiency growth in solar panels comparable to that of computer chips?
    (I think the answer is no). And when, in your estimation, will solar generation eficiency reach the "tipping point" of equivilent cost compared to fossil?
    If solar is "free fuel" in the sense of sustainability, what level of infrastructure- i.e. "sunk cost" creates a sustainability model, say per each 500Kw, or other "optimum size" plant. (I understand that optimums may vary by location complexities, and so on.)
  2. jcsd
  3. Jul 19, 2011 #2


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    Welcome to PF!

    Efficiency can never be above 100%, so it can't possibly rise geometrically. Cost, however, can drop at any rate it wants. So decreasing cost, not increasing efficiency, is where the path to viability lies.

    When? Dunno....maybe 20 years, maybe never.
  4. Jul 21, 2011 #3
    unfortunately, there too many too powerful people at the top that are making sure that we don't get off of oil...they are making way too much money.

    other that the conspiracy theories that people who have invented very efficient engines or engines that run on water or whatever have met a premature accidental death...

    the fact is the oil companies have been lobbying for years and get a lot, a lot of subsidies for their infrastructure, etc...they are the ones that say that solar is too expensive at the present time...well, guess what, if the solar industry received the kind of subsidies that the oil one is getting..solar would definitely be affordable...

    ...100 years ago, I can understand the oil industry needing some help...but today? this companies have billions...they don't need help...I think they should take the subsidy away from oil and give to solar/wind.
  5. Jul 22, 2011 #4


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    This chart by an MIT solar PV pioneer presents one viewpoint. The "Today" marker was ~2009-10. Note however that the price of NG electricity is also dropping. Indeed, I expect those price lines for both gas and coal could be dynamic if solar starts to gain significant share, reducing the demand for those fuels. The price of solar PV today is http://www.solarbuzz.com/facts-and-figures/retail-price-environment/solar-electricity-prices" [Broken] (sunny climate, industrial scale) and falling at 1% per month.
    Last edited by a moderator: May 5, 2017
  6. Jul 22, 2011 #5


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    gsal: That's an entirely political and economic post. PF has other sub forums for that kind of discussion.
  7. Jul 22, 2011 #6
    Sorry. It was probably a bit over the top.

    The reason for the non-technical answer and reference to subsidies was because the OP asks for that "tipping point" / equivalent cost of solar energy compared to fossil...

    ...it was not for the unbalance of subsidies we would already be there...

    that's all I am trying to say.
  8. Jul 22, 2011 #7
    I don't think it is the cost of solar as much as the comparative cost with regards to fossil fuels. It may be that it's not the reduction in the cost of solar as much as the increase in cost of fossil fuels that causes the tipping point. If the oil and solar subsidies were both eliminated we could have an honest competition between the two.

    Personally, I think that if houses were constructed with solar panels on the roof, where practical, with their cost amortized along with the house, people would be much more willing to consider solar.
  9. Jul 22, 2011 #8


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    Well many countries are now subsidizing solar power, and in addition many are also starting to penalize coal via a price on CO2. So despite the conspiracy theories the balance is very much shifting in the other direction in many parts of the world.

    The total percent of power production from PV is current only small and still mostly needs some kind of subsidies (or CO2 penalties) to compete, but the gap is closing pretty fast. I think mesleps graph summarizes the situation pretty well, I think within about five years PV solar power will be competitive (maybe even more so for solar thermal).
  10. Jul 22, 2011 #9


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    http://www.technologyreview.com/energy/32383/" [Broken] :smile:
    Agreed, with some caveats: i) until the storage problem is resolved (cheaply) the PV share of the total will likely be limited to 5-20%, ii) add another five years for PV competition outside the sunbelt and for smaller installations.
    Last edited by a moderator: May 5, 2017
  11. Jul 22, 2011 #10


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    But oil is not competition with solar PV, coal and natural gas are. I doubt very much if we see an increase in their prices given flat electrical demand in the US and shale gas production, absent price premiums forced by the government via regulation.
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