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Solar Flux

  1. Aug 19, 2010 #1
    Hi Guys
    I m trying to make a Stirling engine power by solar heat.
    Somewhere I found out that the solar flux available on earth is abt 1350watts/m2

    Is this heat energy only or "heat & light " combined??

    I m trying to find out if my soar engine will be better than traditional solar cells??

    What is the energy conversion rate for solar panels/m2???
  2. jcsd
  3. Aug 19, 2010 #2
    A Stirling engine is one of the most efficient heat engines known. It is doubtful if a solar panel (notoriously inefficient) would be anywhere near as good at converting heat directly into mechanical movement.

    On the other hand, if you intend to run (say) an electric generator from your engine, forget it. The power developed by a model Stirling is amazingly low - it can barely keep itself running against friction.

    Here's a vid of my own Stirling.

    Last edited by a moderator: Apr 25, 2017
  4. Aug 19, 2010 #3


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    Staff Emeritus
    Science Advisor

    The 1.35 kW/m2 refers to the light and would produce that thermal power if it could be converted to heat at 100% efficiency.

    One could use 10% as a reasonable estimate of the efficiency of PVs.

    World's Highest Photovoltaic Energy Conversion Efficiency Among Monolithically Integrated Flexible Solar Cells = 15.9 %

    There are apparently more efficient PV cells in the works.
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