Solar energy and mirrors

Hey everyone,

I have a question.

Does solar energy get reflected off of mirrors? Light is reflected off of mirrors but is the solar energy that charge solar cells reflected as well? (or well enough to efficiently charge a solar cell i mean)

Example: you have solar cell that is not in direct sunlight. You have perfectly placed mirrors to reflect the most amount of light directly to the solar cells as possible.

Would this still generate electricity? If so, how would the efficiency be this way. (lets say .5 amount of light that normally hits a solar cell in direct sunlight, is able to reach the solar cell not in direct sunlight).

Please help me with this.

Thanks in advance.


  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Solar energy and mirrors

    The simple answer is: yes.

    Solar panels convert visible light into electricity. If there's no light on the panels there's no electricity. If there is light, viola! It doesn't matter if it's reflected light or not. In fact those of us who live in the frozen wastelands of Planet Earth often see output from sunlight reflected off snowpack.

    Unlike thermal solar, however, panels will only put out at their maximum capacity no matter how many extra photons you point at them. This can be above ratings, as in an 'edge of cloud event' where the water molecules concentrate the sun's rays and really wake up the PV's.

    Reflected light will have less energy potential than direct sunlight, due to fact no mirror is 100% reflective. Another problem with using mirrors (aside from it being another big piece of glass to break) is that the sun moves through the day so ideally the mirror would have to be continually re-aligned to provide maximum reflected light; the angle of reflection is equal to the angle of incidence.

    And that's the start of the long answer. There will be other posts from other forum members!:D
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Solar energy and mirrors

    as was said, yes, it will generate from reflected light. be careful if you do this as you could shorten the life of the cells or module because of excessive heat. commercially made modules aren't warranted for higher levels using mirrors.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Solar energy and mirrors

    The best way is to use SNOW as a mirror. Your panels are generally pretty cool if snow is still on the ground, and it's presence can reflect into the panels for a boost, even more if you have MPPT controller.
    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

    gen: ,