How would you mount 20 Kaneka panels at the lowest cost?

BilljustBill
BilljustBill Solar Expert Posts: 219 ✭✭✭
I have 20 of the 60 watt Kaneka solar panels, G-SA060 for a rooftop mount and the weight isn't an issue. There are no shadows on this roof from sun up to sundown. On a 22-1/2 Degree slope, with a 3 year old "Armor Shield II" of asphalt shingles, there is roof space enough to mount one panel below another and span enough for two rows of 10 panels.

Beside commerical racks, how would you mount these panels in a safe installation, but in the most economical way.

How much air cooling space is needed between the roof and panel as the 22-1/2 degree tilt has been shown to be effective by the PV Watts site.

Your ideas and experience are always appreciated,

Bill
Bill

Comments

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    Go it alone...

    Buy stand offs for unirack or for some other aluminum framing stand for other roof mounted equipment, build a frame work of pressure treated 2x4's or if you can split presure treated decking boards 6" mominal decking boards, they tend to be near clear wood better grade I've found than #1 2x4's.

    Build a frame with wood and buy aluminum off angle off cuts to make your mounts for the panels, at least 3/16" thick and try to find 3x2, suggest leaving an inch of space under the panels for ventalation and an inch between the panels.

    Use Stainless steel hardware and read the specs on the pressure treated wood, much of it uses copper or other metals and suggests no direct contact with metal. So make some shims out of plastic. They's be sandwiched between the metal and wood and under panels, so UV exposure is not the threat. drill the holes for hardware slightly oversize to allow for expansion.

    You can find off cuts on Ebay try a search like "aluminum angle lot" or just "aluminum angle. You might also check local aluminum metal supply and see if you can't buy some 1' and shorter off cuts for 2x melt.

    Drilling many holes in your roof will just be tons of fun and very nerve racking...

    Seal them well!
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • sub3marathonman
    sub3marathonman Solar Expert Posts: 300 ✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    You could also try building mounting rails out of UniStrut. Here is their website: http://www.unistrut.us/ . I don't know how much that would save on the price, but I believe you should be able to buy UniStrut locally, so you might save a good bit on shipping.

    I don't know how it would work out, I've never used it. I think I used Unirac, but I'll have to check to be sure.
  • XRinger
    XRinger Solar Expert Posts: 529 ✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    Here are some mounted on PT wood.

    LarryL2800x600.jpg
    http://showmesolar.org/blog/2010/05/

    With an aluminum strap for lightning protection.?.

    I like the basic ground mount system..

    rapspv.jpg
    Humm, do I see some 2x6 PT lumber under those thin-films?

    Cheers,
    Rich
  • XRinger
    XRinger Solar Expert Posts: 529 ✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    I've used the Super-Strut steel (small size) from Lowes on my tracker mount and it works pretty good.

    It's good to get the special Super-strut hardware too.
    channel.jpg
    To use this type of mounting on a roof, you would need a good bit of clearance.
    So you could reach under with a small ratchet wrench. Might be difficult.



    I've used wood too. It's easier to work with and not too heavy.

    solararrayhoist.jpg
    I started off with two panels held by two redwood 2x4s
    and ended up adding two 13' PT 2x4s, so I could add two more panels.
    solarfarm2.jpg

    Someday, when the roof gets old and beat looking.. Maybe, just maybe.. :roll:
  • RCinFLA
    RCinFLA Solar Expert Posts: 1,484 ✭✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    You might also consider PVC pipe structure. I would definitely favor it over any wood mount.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?
    RCinFLA wrote: »
    You might also consider PVC pipe structure. I would definitely favor it over any wood mount.

    Why? doesn't PVC, even the grey stuff become brittle in the sun? also I would think you would need more supports as what I've seen would sag under a small weight.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Brett
    Brett Registered Users Posts: 19
    Re: How would you mount 20 Kaneka panels at the lowest cost?
    Photowhit wrote: »
    Why? doesn't PVC, even the grey stuff become brittle in the sun? also I would think you would need more supports as what I've seen would sag under a small weight.


    I've been reading some threads which detail differences between various type of solar panels. I realize you already have your investment, but the nature of boating seems to be very destructive to solar.

    Maybe this is a job for thin film products, something that could just be rolled out on a deck, or put behind a piece of lexan,something a little more forgiving with the flexing mount.
  • BilljustBill
    BilljustBill Solar Expert Posts: 219 ✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    Thank you for your ideas and working photos. Every one has its strengths and as I ready my installation; taking parts of each idea gives me some help without spending a lot of time on "Trial and Error" or "Reinventing the Wheel".

    Is there a place to buy the hold-down clamps in bulk to keep the cost down? Or should I just use short lengths of angle aluminum bolted though the sides of the Kaneka panels without any worries that doing that would void any warranty?

    Thank you, again
    Bill
    Bill
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    I've seen a diagram for the 60 watt panels showing 4 mounting holes at the bottom, I'd just run a Stainless Steel bolt through the hole and through the aluminum angle, use SS washers and a nylon lock nut. Best I could do in 5 minutes, but use 2 screws through the wood, Like this or 90 degrees from this is your wood is running the other direction;

    mount.gif?t=1300852595

    Hope this makes sense. Leave a gap so you don't trap hot air under the panel if your running across the top with wood. I can't seam to make this sound right, hope you understand. if the wood is running across between the pannels, you can mount 2 panels with a single piece of aluminum, I'd also leave a gap between the panels, just a little one for air flow, maybe a 1/4". I have sample of these but won't be at home except weekend for the next 6 weeks, I'm day time doggie walker for a puppie who will get another new hip in the morning.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: How would you mount 20 Kaneka panels at the lowest cost?

    Had to go home so here's photos of 2 home made mounts;

    x1-for-2panels.jpg?t=1300998071

    x1-per-panel.jpg?t=1300998071

    The one mount holding 2 panels is 3/16 x 1 1/2" angle. holding 115 watt evergreen. The single mounts are 1/4" x 2x 2 1/2" angle (I think) holding the NingBo 170 watt panel, the NingBo's aluminum is more robust. These are obviously not flush mounted but rather free standing. The white piece behind the long mount is plastic to shield the aluminum from the copper in the pressure treated wood. What ever the salt is in that perticular pressure treating is really rough, I screwwed in a dip galz screw one day and pulled out a bright the next!
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.