Is Solar Dangerous on Metal Roofs?

kadesmith
kadesmith Registered Users Posts: 9
I just got to thinking about this, is it dangerous to install solar panels on a metal roof? Electricty and metal just don't seem to go well together.

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?

    Just in the rain :D
    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 ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?

    It's not a problem.
    Usually only the panels are on the roof (except in the case of micro inverter installs). They are a self-limiting current source. Wires are insulated, run in conduit, panels fused properly, mounts grounded. Thus if any short occurs a fuse will pop, and that's about the end of it.

    The exception to this would be poorly constructed "homemade" panels that use something flammable (like plywood) for backing. Unfortunately we still see this from time to time.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    Re: Is Solar Dangerous on Metal Roofs?

    All external (touchable by end user) metal should be connected by copper cable together and to earth ground (building ground/water pipe/etc. depending on your local code).

    If there are any shorts--the metal will not become electrified and any excess current should blow a circuit breaker/fuses (if used/required).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • kadesmith
    kadesmith Registered Users Posts: 9
    Re: Is Solar Dangerous on Metal Roofs?
    mike90045 wrote: »
    Just in the rain :D
    Brings a whole new meaning to singing in the rain.

    Sounds like as long as it's done professional or atleast with professional parts then it's not a bad thing.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?
    kadesmith wrote: »
    Brings a whole new meaning to singing in the rain.

    Sounds like as long as it's done professional or atleast with professional parts then it's not a bad thing.

    In fact it may be less risky than asphalt shingles because metal is not flammable. It is possible to get an arc going that could ignite shingles which would only ground out on metal.

    It's all about the installation. :D
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?

    it's not the roof that makes electricity dangerous. no matter the roof involved, one has to be a respecter of electricity.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?

    I love steel roofs and install them at every chance given a choice. My problem with PV and steel roofs is having to climb up on them for some reason! I can climb a 12/12 pitch asphalt roof without a problem, but a 4/12 with a drop of dew on your boots and you are on the ground! I did not install a steel roof on our new place strictly for that reason, since I have to get up and clean the chimney a couple of times a winter, and sweep the panels of snow once in a while.

    Tony
  • dagr51
    dagr51 Solar Expert Posts: 72 ✭✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?
    icarus wrote: »
    I can climb a 12/12 pitch asphalt roof without a problem

    Tony

    You're a better man than me! (or is it "I"?)
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?

    I thought Tony was an old goat, not a mountain goat:p

    Ralph
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Is Solar Dangerous on Metal Roofs?

    I don't suggest much of what I do! I framed houses for a very long time, so scampering around carrying plywood up and down roof decks is sort of second nature. A 12/12 with toe boards works alright, but you really should have proper fall protection! (It all sort of explains my knee and ankle problems!)

    T