Determining the Wind Rating for a DIY Solar Ground Mount

Hey Guys!

I'm constructing a ground mount for my solar panel that is similar to the one found in the video. While putting the system in pretty straightforward, I still live in Florida, so I want to be reasonably sure that the system can withstand some of the weather that we get here. The system is not a grid tie-in, nor does it need to signed off by PE; but I would still like to know what kind of wind rating my system will have (I would like for the system to be able to withstand at least 150 MPH winds). I have an undergraduate degree in Mechanical Engineering, but it's been awhile since I've worked with any structural equations. Do you guys have any recommendations on how to proceed?


  • mike95490mike95490 Solar Expert Posts: 9,462 ✭✭✭✭✭
    soil analysis to see how stable it is when wet. Then you size the anchors to hold the wind load in n soil You may need to hire an engineer to check or school you in the method. I'm an EE and don't know the mech side too well.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
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    gen: ,

  • Dave AngeliniDave Angelini Solar Expert Posts: 6,076 ✭✭✭✭✭
    A test commonly used is to calculate the wind force and then weigh the mount down and check the deflection. There should be very little. The 2 inch pipe should not have holes but clamps. At least I have never seen holes in a pipe on the mounts of Pro Solar, UniRac. DPW, or Array Technology.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
    E-mail [email protected]

  • BB.BB. Super Moderators, Administrators Posts: 32,216 admin
    Unless you have a very large diameter vertical pipe--I would be wanting to see diagonal bracing.

    To give yourself an idea of what level of forces you are looking at:

    Design Loads*
    Two rail system
    113 psf downward
    64 psf upward
    Design Loads*
    Three rail system
    178 psf downward
    64 psf upward
    Design Loads*
    Edge mounting
    178 psf downward
    41 psf upward
    * Please refer to the Sunmodule installation instructions for the details associated with these load cases.

    That 280 Watt panel is about 11.85 square feet. A 64psf loading would be 758 lbs per panel. Put three of those on a rack and that is the equivalent of hanging your car the structure.

    And given that a typical design factor of 10x (the structure has to support ~10x more design load before failure)--You can see that this can add up really quickly (~20,000 lbs to "break" the mount for 3 panels).

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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