Forum Discussion

Trackrig's avatar
Trackrig
Explorer II
May 18, 2017

Placement of solar panels on a TT roof.

I have a 2007 Nash 26X TT that I'm about to put solar on. Because it's a smaller TT with lots of other "stuff" on the way on the roof, it looks like I'll have to go with 100W panels about 22" x 48".

There's room for three of them without a problem on the forward half of the TT. I can fit a forth one in if it's beside the A/C. Then depending on which direction I park, a fair percentage of time the A/C will cast a strong shadow over that forth panel. Will that just cut out the solar production from that particular panel, or will it hurt the output of the three also?

I could most likely get by with 300W but I don't mind spending the money on the forth panel for getting partial use out it as long as it doesn't hurt the overall output of the other three. I want to do the project and be done with it and not back up there next year to change things around.

Bill
  • RollandB's avatar
    RollandB
    Explorer
    May 18, 2017
    One comment on allowing for a tilt option, I purchased tilt bars mostly for having the ability to raise them when wiring and to have them raised when cleaning the roof.
  • pianotuna's avatar
    pianotuna
    Nomad III
    May 18, 2017
    Hi,

    good choice on the controller--get the temperature probe.

    raised is not tilted.

    definitely do parallel wiring with a combiner box on the roof.

    Trackrig wrote:
    I could tilt them, but doubt if I will. The only time they will stay up for a while is during hunting season and then there will be frost on the roof when I go to leave with the TT in the morning. The roof is fairly rounded.

    The awning and refer will be on the opposite side from the 4th panel which will keep it out of the shade of A/C and refer out of heat - all works out well if the site accommodates parking that way. The batwing will also be out of the way from the panels, but I doubt it will be off of the roof as well be at least 75 miles from a TV transmitter and there's mountains in between.

    I'll probably be using a Grape controller.

    Per the above, I'll be wiring in parallel.

    Bill
  • KMLsquared's avatar
    KMLsquared
    Explorer
    May 18, 2017
    Lwiddis wrote:
    I wish I had a fourth 100 watt panel in the back but putting three on the front works very well. My experience shows the most shade will be at the rear of the campsite so the front of the TT is best IMO. As 2oldman says, wire in parallel. Series is nice but in the real world....



    This is good info. I was thinking that the front of the trailer is less likely to be shaded.
  • Trackrig's avatar
    Trackrig
    Explorer II
    May 18, 2017
    I could tilt them, but doubt if I will. The only time they will stay up for a while is during hunting season and then there will be frost on the roof when I go to leave with the TT in the morning. The roof is fairly rounded.

    The awning and refer will be on the opposite side from the 4th panel which will keep it out of the shade of A/C and refer out of heat - all works out well if the site accommodates parking that way. The batwing will also be out of the way from the panels, but I doubt it will be off of the roof as well be at least 75 miles from a TV transmitter and there's mountains in between.

    I'll probably be using a Grape controller.

    Per the above, I'll be wiring in parallel.

    Bill
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    May 18, 2017
    I like others have raised panels which will allow you better placement and panel performance..
  • MrWizard's avatar
    MrWizard
    Moderator
    May 18, 2017
    four panels parallel
    shade on one panel, only hurts that panel
    the other panels will continue to have output

    do you use your awning ?

    i will normally park awning side to the sun, if I have the choice
    so put the 4th panel on that side of the A/C unit, it will be in the sun more times than in the shade

    I know..depends on where the Batwing lays down !
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    May 18, 2017
    I wish I had a fourth 100 watt panel in the back but putting three on the front works very well. My experience shows the most shade will be at the rear of the campsite so the front of the TT is best IMO. As 2oldman says, wire in parallel. Series is nice but in the real world....
  • pianotuna's avatar
    pianotuna
    Nomad III
    May 18, 2017
    Always exciting to get solar!

    Consider raising the panel beside the air conditioner up higher than the rest. AM Solar sells mounts that are 3.75 inches tall.

    What charge controller are you planning on using?

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