Home  5  Books  5  GBEzine  5  News  5  HelpDesk  5  Register  5  GreenBuilding.co.uk
Not signed in (Sign In)

Categories



Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

PLEASE NOTE: A download link for Volume 1 will be sent to you by email and Volume 2 will be sent to you by post as a book.
Buy individually or both books together. Delivery is free!


powered by Surfing Waves




Vanilla 1.0.3 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to new Forum Visitors
 Join the forum now and benefit from discussions with thousands of other green building fans and discounts on Green Building Press publications: Apply now.




General: East West PV array efficiency

Bottom of Page

31 to 39 of 39

  1. <
  2. 1
  3. 2
  4. >
  1.  
    Posted By: renewablejohnThe bifacial panels face east west with pivot point north south, rotate through 90 degree and that makes the panel horizontal the panel is then equivalent to south facing at 0 degrees.

    A S facing panel at 0 deg is about 18% less efficient than an inclined S facing panel

    The photos from the article above shows vertical panels with a large amount of space between rows to avoid shading. It looks as if there could be substantially more panels / m2 of land if panels are mounted conventionally inclined.

    How will the panels be rotated twice a day? (and at differing times through the year) will there be motorisation and automation (expensive) or manually (labour intensive) Studies I recall rarely find that the expense of automated tracking systems are worth the effort and expense.

    If you need a more even spread of energy production over any given day would it be easier to have some panels vertical E/W and some inclined S and avoid the complications of moving panels either manually or automated?
  2.  
    Posted By: Peter_in_Hungary
    Posted By: renewablejohnThe bifacial panels face east west with pivot point north south, rotate through 90 degree and that makes the panel horizontal the panel is then equivalent to south facing at 0 degrees.

    A S facing panel at 0 deg is about 18% less efficient than an inclined S facing panel

    The photos from the article above shows vertical panels with a large amount of space between rows to avoid shading. It looks as if there could be substantially more panels / m2 of land if panels are mounted conventionally inclined.

    How will the panels be rotated twice a day? (and at differing times through the year) will there be motorisation and automation (expensive) or manually (labour intensive) Studies I recall rarely find that the expense of automated tracking systems are worth the effort and expense.

    If you need a more even spread of energy production over any given day would it be easier to have some panels vertical E/W and some inclined S and avoid the complications of moving panels either manually or automated?

    If 18% down from being horizontal but 20% up from solar relection then I can live with that. Panels will be rotated by the same technology as my glasshouse window opening and closing.
    The point of rotating is to overcome the dead point when the sun is directly over the vertical panel.
  3.  
    Posted By: renewablejohnPanels will be rotated by the same technology as my glasshouse window opening and closing.

    Which is....??
  4.  
    Posted By: Peter_in_Hungary
    Posted By: renewablejohnPanels will be rotated by the same technology as my glasshouse window opening and closing.

    Which is....??


    Standard programmable linear chain window actuator. Can control both time when window is opened and closed as well as actuation length. In theory can rotate anywhere between 0-360 degree but 90 degrees is all that is required.
  5.  
    >>>> "The photos from the article above shows vertical panels with a large amount of space between rows to avoid shading. It looks as if there could be substantially more panels / m2 of land if panels are mounted conventionally inclined."

    Yes, as mentioned, the vertical e-w configuration is for where land is already in productive use for farming/carpark/roadside/nature and you just want to add some PV income whilst taking minimal land area away from its existing use.

    If the PV was replacing the existing land use, then the developer would want to cram more panels closer to make that swap worthwhile.

    Solar arrays in UK were previously funded by subsidy schemes, ROCs/CFDs (or ETs and FITs for domestic) which pay the same rate irrespective of the time of day, favouring South facing panels. So UK now has a lot of South facing solar capacity, with a lunchtime power peak.

    The present huge rush to build subsidy-free solar capacity, is funded by electricity sales, so is starting to design for morning/evening generation when the prices are expected to be higher.
    • CommentAuthorjon
    • CommentTimeSep 20th 2022
     
    "Youll not need any central inverters if you are using micro inverters fitted to each panel. Or are you meaning optimsers which are different to microinverters??"

    Hi Phil

    I've got one face that is full sun regardless (east) except in the depths of winter (when only one end of that 6 panel array gets sun)

    The other face (west) may get some shadow (two panels at a time)

    So thinking of a central inverter for the east face, perhaps with optimisers, but unsure about what to do about the west. It's very hard to find advisors in my area.

    I'll be making a structural exoskin for these panels (I'm a structural engineer: sounds bonkers but makes sense in this instance).
    • CommentAuthorphiledge
    • CommentTimeSep 20th 2022
     
    With conventionally wired panels that are plugged into the adjacent panels to form a big loop, if one or more panels are shaded it brings the output of the whole loop down to that of the shaded panels. If you have your panels facing different directions but all wired in one loop then those facing the sun will be limited in output by those facing a different direction. By facing away from the sun they are effectively shaded or partly shaded whilst those facing the sun are unshaded.

    Your east facing panels need to be wired separately from the others. If the west facing panels have a mix of shaded/unshaded then really they dont want wiring together but to use optimisers or micro inverters. If you are going to use optimisers/micro inverters for the west facing panels and you have some winter shading on the east face, then use optimisers/micro inverters throughout. We have panels facing SE, SW and NW and they are all on Solaredge optimisers giving a great spread of generation through the day.
    • CommentAuthorjon
    • CommentTimeSep 27th 2022
     
    Thanks phil. I'd come to that conclusion. Confirmation much appreciated.
  9.  
    I've just noticed that the palm tree in our garden aligns it's leaves with the fan facing exactly south.
    That seems to suggest that it knows that way will maximise the amount of solar energy it generates. :)

31 to 39 of 39

  1. <
  2. 1
  3. 2
  4. >
Add your comments

    Username Password
  • Format comments as
 
Back to Discussions Top of Page
   
The Ecobuilding Buzz
Site Map    |   Home    |   View Cart    |   Pressroom   |   Business   |   Links   
Logout    

© Green Building Press