What to do for a concrete base for 52 pannels

t12zh
t12zh Solar Expert Posts: 62 ✭✭✭✭
I have a solar man that ask me what i could do for him.
I do work at a Concrete company.
Install a whole bunch of caisons or go with a footer.
He knows i drill hole's all the time and thought caisons would be good.
I think that caisons are too close together and too much work, a footer would be better i think unless there is a better way.

It is in Colorado and we do get snow.
How high up from the ground is standard.
Greg

Comments

  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: What to do for a concrete base for 52 pannels

    What ever the Engineered panel support structure requires ...

    A continious footer is nuts, what going below the frost line that like would be enough concrete to build a house foundation?

    As a guess, sonent tubes into backhoe drilled holes is the correct anwser, but thats for the PE ( Professional Engineer ) to spec
  • t12zh
    t12zh Solar Expert Posts: 62 ✭✭✭✭
    Re: What to do for a concrete base for 52 pannels

    Yes
    That is i think why he asked me because i have a Drill rig and have been drilling caisons for the last 8 years.
    He can drill them with his Bobcat real easy but was looking for the best way.
    There is no Professional Engineer.
    He is installing 52 pannels in a low wind area.
    Frost is 3 feet.
    Thankyou
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: What to do for a concrete base for 52 pannels

    I'll side with the backhoe and auger, and then http://www.sonotube.com/ concrete forms. Make an array of posts.
    I guess pole mount racks can handle arrays up to 8 panels, maybe only 6 depending on panel size. Rack Mfg would have info on foundation requirements. I'd spend the $$ and use fiber reinforced concrete rather then trying to wind up a bunch of rebar
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: What to do for a concrete base for 52 pannels

    i don't think it will require as much concrete as everybody might think. yes windloading has to be accounted for, but with the frost line down that deep it may be possible to not need a large solid tube of concrete down that far. my guess would be about 4ft down to stay below the frostline with 3/4ft in diameter, but tapered as it goes up to say 4 inches in diameter. imho the shear length of this and its weight will far exceed any requirements engineers may need speced for it and i site the requirements imposed upon towers used for large 2way radio antennas when up beyond 50ft and how much area and depth is typically required of them. the stresses imposed on the antenna tower will far exceed a pv mount's stresses and note that there will be many of these linking the pv mounts together and not just one single tall support as needed for an antenna.
    of course i may not be fully understanding how it is you propose them to be mounted.