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Water cooled solar panels for significant output boost

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  • LordAC
    replied
    Hi!

    I'm doing this experiment in my thesis.
    Basically this will have a closed loop water system. I'll see if what I get in the solar panels efficiency will somehow compensate for the use of water and electricity (water pump).
    In addition to this, the idea is also clear the panel's dirt and dust (this greatly decreases the efficiency).

    I believe the main problem here the water evaporation and the water "contamination".

    Leave a comment:


  • posplayr
    replied
    I just read most of this thread and found it very interesting for a variety of reasons.

    It is obvious that there are some very intelligent people here.

    PS I introduced myself here.

    http://www.solarpaneltalk.com/showth...489#post161489

    Leave a comment:


  • inetdog
    replied
    Originally posted by Sunking View Post
    Nuke him, you got nothing to loose.
    Already did....

    Leave a comment:


  • Sunking
    replied
    Originally posted by inetdog View Post
    Thanks for the tip. That explains why he went up to ten and stopped!
    Nuke him, you got nothing to loose.

    Leave a comment:


  • inetdog
    replied
    Originally posted by Sunking View Post
    My guess he already has already gathered your member list for a SPAM attack via PM. If we see any of this on MH Forum we nuke them immediately, or shoot first and kill, then ask questions later.
    Thanks for the tip. That explains why he went up to ten and stopped!

    Leave a comment:


  • Sunking
    replied
    Originally posted by inetdog View Post
    Not yet a proven spammer, just a guy who has made ten posts and not actually said anything of interest. We are watching him though. Let us know if he does anything directly outrageous.
    We are particularly sensitive to people who drop inane posts and go back and edit spam links into them later.
    My guess he already has already gathered your member list for a SPAM attack via PM. If we see any of this on MH Forum we nuke them immediately, or shoot first and kill, then ask questions later.

    Leave a comment:


  • inetdog
    replied
    Originally posted by Sunking View Post
    Get lost SPAMMER
    Not yet a proven spammer, just a guy who has made ten posts and not actually said anything of interest. We are watching him though. Let us know if he does anything directly outrageous.
    We are particularly sensitive to people who drop inane posts and go back and edit spam links into them later.

    Leave a comment:


  • Sunking
    replied
    Get lost SPAMMER

    Leave a comment:


  • Philippeberard
    replied
    Good discuss thanks i will take new idea.

    Leave a comment:


  • J.P.M.
    replied
    Originally posted by pleppik View Post
    It was here:



    It's true that he didn't actually use the word "thermodynamics," but there's not really any other law of physics which could apply.

    But I think we've truly beaten this dead horse to death (or something). I apologize for yanking this thread so far off the original topic.
    The original topic was mostly a waste of time anyway. Might as well waste a bit more to clarify a few things.

    To the extent that some parts of Thermodynamics share the world of Physics, how about the 1st law of Themodynamics being applicable as it relates to an energy balance on the system, which when applied to this situation with a control volume slapped around the heat recovery system would mean an examination and analysis to determine if more energy is required to cross the boundary surface into the control volume to make the heat recovery system work than is recovered and crosses the boundary surface in the other direction.

    It may or may not be true that more energy is used than recovered in the subject system. But either way, contrary to your statement about no other laws of Physics being applicable I'd suggest the 1st law as being very applicable.

    And while I'm not speaking (writing) for Derrick, my interpretation of what he had in mind was more with respect to the bottom line cost of the energy necessary to produce the resulting increase in system efficiency and account for all the parasitic extra costs associated with such heat recovery systems - that cost being greater than the value of any recovered heat.

    That is, even if you can save more energy on an absolute basis than you input, the difference in the [U]quality[/U] of the energy [U]input[/U] and the cost of its low entropy (as in the high cost of electricity) compared to the relatively higher entropy (and lower value) of the recovered waste heat, plus the costs of the makeup water, plus the added cost(s) of maintaining and repairing the equipment required to keep it functional in what may well be way off design conditions, are perhaps and probably higher than the value of not recovering the waste heat and supplying it by some other method(s).

    I'm of the opinion that, all things considered, it seems fairly certain that the heat recovery system as described would have the effect of a larger increase in the entropy of the surroundings than the entropy of the heat recovery system, resulting in a net increase in the entropy of the universe. That fits some of what I learned about the 2d Law. It would also cost more than what would be saved, both short and long term.

    So, not only did Derrick's tirade about system inefficiency [U]not[/U] say it was a violation of the 2d Law, but in a very real way, with a little thought, may have served as yet another consequent example and possible verification of it.

    In either case, I concur with your latest statement that he indeed never mentioned the 2d law of Thermodynamics, contrary to your prior statement.

    Leave a comment:


  • pleppik
    replied
    Originally posted by J.P.M. View Post
    I must have missed the part where anyone was claiming a violation of the 2d Law of Thermodynamics. Where was that ?
    It was here:

    You are fighting the Law of Physics and cannot change those Laws no matter what. It is the same reason you cannot use a trampoline to get into orbit, or pull a train with a motor cycle. You will never recover the energy you put into cooling. You are wasting energy, not making it.
    It's true that he didn't actually use the word "thermodynamics," but there's not really any other law of physics which could apply.

    But I think we've truly beaten this dead horse to death (or something). I apologize for yanking this thread so far off the original topic.

    Leave a comment:


  • J.P.M.
    replied
    Originally posted by pleppik View Post
    I agree with all this. The only thing I objected to was the claim that boosting total output by cooling the panels would violate the 2nd law of thermodynamics.

    In my book there's a huge and important difference between "isn't economical" and "violates the laws of physics."
    I must have missed the part where anyone was claiming a violation of the 2d Law of Thermodynamics. Where was that ?

    Leave a comment:


  • Ian S
    replied
    Originally posted by pleppik View Post
    I agree with all this. The only thing I objected to was the claim that boosting total output by cooling the panels would violate the 2nd law of thermodynamics.

    In my book there's a huge and important difference between "isn't economical" and "violates the laws of physics."


    You're exactly right and that's the whole problem with this thread. Some "expert" proclaims that evaporative cooling violates the laws of physics and others leap to his defense by changing the subject to one of economics. Such antics are par for the course around here and are good for a chuckle if nothing else.

    Leave a comment:


  • pleppik
    replied
    Originally posted by J.P.M. View Post
    So then you know the difference between the Carnot efficiency limit based on temp. and the Thermodynamic efficiency limit for various solar cell technologies having something to do with band gap energies, right ?
    Yes, exactly right. Which is why it's not a violation of thermodynamics to boost the efficiency of PV panels by cooling them. Which was my entire point.

    The 2nd law limits how much useful work you can extract from a temperature difference, regardless of whether the mechanism for extracting the energy is a heat engine, thermoelectric generator, or photovoltaic cell. But the efficiency of a PV cell is so far below the thermodynamic limit that there's a lot of room for improvement before you start running into the laws of physics.

    Leave a comment:


  • pleppik
    replied
    Originally posted by Sunking View Post
    All I'm trying to say is this idea is not new. Universities, scientist, and engineers have tried 9 times to Sunday for the last 20 years to make it work. That group are my superiors and peers, and when they tell me it cannot work economically or establish a positive EROI, I believe them.
    I agree with all this. The only thing I objected to was the claim that boosting total output by cooling the panels would violate the 2nd law of thermodynamics.

    In my book there's a huge and important difference between "isn't economical" and "violates the laws of physics."

    Leave a comment:

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