Leaf build-up under panels

strawbale Solar Expert Posts: 31 ✭✭✭
Leaves have been building up over the 10+ years since installation. I can still see light when sighting up under them, but barely. I was originally concerned primarily for the roof with the leaves holding moisture, etc., but I am now also aware that this is likely reducing our production and life of the panels. A study has shown that production decreases .2 to .5% for every 1°C increase in temperature. I have 33 panels in 3 rows. I'm wondering how others have cleared leaves from under their panels. My current thought is to get one of those leaf-vac/mulchers and attach a length of 2" or 3" pvc to the vacuum hose and use that to try to vacuum out the leaves. One concern I have is that there are some wires dangling down from the panels (not good, I know) and I wouldn't want to be damaging them in any way. Other ideas?  Fyi, I and my neighbor took down some trees over these years, so there should be significantly less leaves coming on our roof than what there was earlier.


  • BB.
    BB. Super Moderators, Administrators Posts: 33,402 admin
    Other problem is that small chewing animals build nests in leaf litter... So any exposed wiring has a chance of getting damaged.

    When I tried to clean under my panels, I had to mechanically clear with some sort of rake/hook type thing--I did not have any luck with water/blower/etc. to clear under my panels. Your mileage may vary.

    After you do clean, putting some sort of screen around the roof gap may help...

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • garynappi
    garynappi Registered Users Posts: 99 ✭✭
    edited May 2020 #3
    If you have access to one, try a pressure cleaner. 

    I have my PV's on a vertical wall, spider webs and leaf debris easily blow away using my pressure cleaner from a distance. I can also clean the surface of panels, but in both cases I don't get really close to the panels, I use a wide angle nozzle and get just close enough to clear and clean them. 

    A pressure cleaner used too close with a narrow nozzle can force water where nature never could, be careful if you do use one. 
  • strawbale
    strawbale Solar Expert Posts: 31 ✭✭✭
    I finally got around to doing this today, using a leaf blower. I could clear about 3/4 of the area with the blower as it was and then needed to duct tape a 10' piece of pvc pipe to the blower to reach the lower (working from the top) central area of the panels where the leaves had piled up, especially after my blowing. It was a bit challenging, but worked okay and I'm glad it is finished. It of course made a huge mess below, but the blower cleaned that up too.