2K GT layout and components.

lipets
lipets Solar Expert Posts: 61 ✭✭
I just wanted to go over system and see if the experts here agree and can offer advise.

8 panels fixed at same angle as latitude 34 N GA. This is going to be built as a SIP's passive solar home

I want to mount them on a wooden pergola with metal rails something along these lines Attachment not found.



The panels would be butted together to make a water tight roof over a patio, possibly screened in, this would be attached to the west side of the house.

The panels I can get thru a local dealer are REC 260W or Suniva 270W ( open to other ideas)

Do I wire those in series or parallel?

both have about the same spec's

V 30
Current 8.4
open V 37.6
Short 9A

I was going to mount a combiner (thinking Midnite solar units, what others might you recommend?)

use conduit to run I'm guessing #10 wire to DC disconnect (any suggestions on one of those)

Inverter, I like the Sonny boy 3000 TL

AC disconnect (any suggestions on one of those)

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    You are looking at Grid Tied--Correct (Sunnyboy 3000 TL). In general, most central GT inverters have around a 200-400 volt working voltage... So you would put something like 8-12 of those in series for the correct Vmp-array working voltage and desired wattage (you need to read the manual in detail, many vendors have a GT Array calculator for their products).

    You would not need a combiner box for this type of array (one or two parallel high voltage strings). Many GT inverters have their own disconnects (DC/AC) either standard or as an option.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • lipets
    lipets Solar Expert Posts: 61 ✭✭
    It looks like the issue of 8 panels with the 3000 was raised here in post #3 and claims it works.

    "I am planning on a single string array of 8 250 W panels. (SMA tech services says that while the 3000TL inverter is over-sized "it will work fine", and sent a computer analysis when I asked for assurance). "

    I intend to add more panels later on, so I want to be over-sized.
  • lipets
    lipets Solar Expert Posts: 61 ✭✭
    Ok spoke to GA Power solar dept, they have no issue with the plan, they don't call it net metering, they buy back the excess at 4.5 cents, thought it was more but their rate is 9 cents so I suppose it makes sense. I have to sign a simple 4 page 5 year agreement, no inspections buy them.

    So when I get my buildings electrical inspection all the solar is supposed be done by that inspector........should be interesting assuming they don't see that many or any in this very small county.