Is adjustable tilt worth it?

I had a 10K fixed ground mount installed this spring. I now question whether I should have made it an adjustable tilt to capture a more direct angle during the four seasons. I know I can fashion a way to do this but wonder if it is worth it. Could somebody that has the adjustable tilt tell me if it's worth the trouble to do this? What percent increase could I expect if I do it also? I live in PA at about 40 degrees. Thanks

Comments

  • RCinFLA
    RCinFLA Solar Expert Posts: 1,484 ✭✭✭✭
    Re: Is adjustable tilt worth it?

    Look here at the +/- 15deg Lat numbers at various time of year for your location.

    http://rredc.nrel.gov/solar/pubs/redbook/

    Looks like about 10% possible yield improvement.
  • solarix
    solarix Solar Expert Posts: 713 ✭✭
    Re: Is adjustable tilt worth it?

    Its a significant gain for the effort of reworking the mounts twice a year, however I've never had a customer follow through with actually doing it as it is kind of hard for one person to do it by themselves. You might be just the one though.
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Re: Is adjustable tilt worth it?

    I worked the numbers from pvwatts site and the seasonal adjustment I can do on my 10kw array comes to 4% gain by doing so. Over 20 years of my contract with the utility that's about $8800 dollars more revenue, which is more than what the extra steel and engineering cost to make adjustment possible.

    Not a lot on a year's revenue, about $500, but over the long haul it's worth it. And it's engineered so one person can do the work.

    Ralph
  • peakbagger
    peakbagger Solar Expert Posts: 341 ✭✭✭
    Re: Is adjustable tilt worth it?

    If you get snow in the winter, its worth tilting the panels to a steeper angle as the snow slides off quicker. I also find the steeper tilt helps with sun reflected off the snow in the winter. On a cold sunny day, I go well over the factory ratings on the panels. I think this reflectance is big part of the boost in output and I dont know if the various output models take this into effect as it is site specific.

    I designed mine so that I can do them myself with a socket wrench, its takes about 5 minutes. I have seen other installs that require hydraulic jacks and a couple of people.
  • jcgee88
    jcgee88 Solar Expert Posts: 154 ✭✭
    Re: Is adjustable tilt worth it?
    solarix wrote: »
    ...I've never had a customer follow through with actually doing it as it is kind of hard for one person to do it by themselves.

    My contractor said the same thing about my array, that is, I would
    need 3-4 people to do the adjustment. My candidate string is
    nine panels, mounted landscape orientation, all locked together.
    It spans about 50 feet and weighs about 400 lbs. Definitely not
    a one-person job, if it were a manual operation. I figured that
    getting a mechanized solution would cost so much that there is
    little net gain.

    In any case, are there off the shelf racking solutions which allow
    a manual change in tilt angle?

    [My rack hardware is Unirac.]

    John
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Is adjustable tilt worth it?

    The further from the equator, the more it's worth it.
    My panels are mounted two per rack, so I can switch them between Summer/Winter by myself in about 15 minutes just by adding or removing the "legs" at the top.
  • dwh
    dwh Solar Expert Posts: 1,341 ✭✭✭
    Re: Is adjustable tilt worth it?

    My camper van has 3 of this sort of gizmo welded to the frame for leveling:

    http://www.amazon.com/Camco-57421-Olympian-Scissor-Jack/dp/B000760FXE

    I operate them with a Ryobi 18v battery drill and a 5/8" socket. Works great as long as you keep them greased.

    Should be able to make a tilt rig with one or more of these and they can certainly handle the weight. And they don't move once they are set either.


    (Why 3 instead of 4? Dunno, it was like that when I bought it. Two in the back and one in the front under the passenger door.)
  • Roderick
    Roderick Solar Expert Posts: 253 ✭✭
    Re: Is adjustable tilt worth it?

    Our array was put in with the possibility for tilt. What we did was put only 3 modules per rack, and leave slack in the wiring, so it could be tilted by one person (and I would be the one). This led to additional cost for the racks. Did I ever go up there in the winter and re-tilt each rack? No. Too much trouble.

    Here's what it looks like, if you're interested: http://roderick.hostcell.net/solar/Photovoltaic_Array.JPG