New 9.2 KW System

tecman
tecman Registered Users Posts: 13
So I am new to the forum. I am in the middle of self installing a 9.2 KW grid tie system. Already installed and wired id a Fronius 10.0-1 inverter. Waiting for the excavator to come in a week in a half to clear the ground. Already I have the Schletter PVMax 3 rack. I will be installing 40 Bosch 230 W panels. PVWatts says I should get 12,000h/yr. I hoped to be making power last month, but between the power company, local permitting, etc things have moved very slowly. I take the long view that these months are a small percentage of what will be produced.

As for other details, I am heating/cooling with 2 GSHPs for a few years now. Besides the lowered cost, it is great that you still get great cooling no matter how hot it is and heat when it is in the single digits. I installed backup heat in the units, but they have never come on. Just insurance in case of a mechanical issue.

After the ground is cleared and my footers are inspected, things should start to move more quickly.

paul

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: New 9.2 KW System

    welcome to the forum. i find those racks to be very interesting and it may interest some of those looking for carport designs as they have quite a variety. good luck on the install and keep us informed.
  • tecman
    tecman Registered Users Posts: 13
    Re: New 9.2 KW System

    I had quite a time getting Schletter to "approve" using concrete footers, rather than the concrete ballasts they show. The recommended footer sizes are ridiculous compared to most everyone else in the industry. 24" x 7.5 feet deep is what is shown. Iron ridge has nearly an identical size rack system using 12" x 4' or 16" x 3" footers.

    paul
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: New 9.2 KW System

    so what did they allow for as i agree 2ft x 7.5ft is huge? i'm sure they did the loading calcs for their normally accepted footer dimensions. do you know what it was and how does the compromise they are allowing you compare if you know?
  • tecman
    tecman Registered Users Posts: 13
    Re: New 9.2 KW System

    They were inflexible on the footers without a soil analysis done by a certified engineering firm. Since I had a PA stamped design for an identical rack from another manufacturer, I am going to use those footer dimensions. 10 piers, 12" diameter and 4' deep. The two designs from the two companies are identical in dimension, panel angle, etc and only the material shapes are different (different extrusions).

    paul
  • tecman
    tecman Registered Users Posts: 13
    Re: New 9.2 KW System

    After a couple of months of intermittent work, and the rainiest August on record, I am finished and up and running.

    First steps were getting the ground cleared and putting in the footers. I had a neighbor come by and clear the land and remove a few trees. The before and after pit tells the story. Next came digging the footers, which I ended up doing 3 times, due to heavy rain and hurricane Irene. Finally got the footers poured and assembled the Schletter ground mount racking system.
  • tecman
    tecman Registered Users Posts: 13
    Re: New 9.2 KW System

    In parallel with the other work, I got the inverter mounted and wired, meter base installed, main breaker changed and the outside AC disconnect mounted. Inside the conduit was EMT, transitioning to rigid conduit on the last leg to best weatherproof the outside fittings.

    Next pulled the wires for 4 strings and ground. Terminated the wiring in two junction boxes on the Schletter rack.

    The panels arrived and mounted on one long day. The result was a finished solar array. Did final hookup and wiring and got the approval of the electrical inspector, and filed the paperwork with the local utility.

    Finally stitched on the disconnects and configured the inverter. In the week it has been on-line, only one partly sunny day. That produced 39 KWH. Unfortunately every other day has been totally overcast and/or raining. I am impressed that even with a total overcast, gray sky, I have seen 1 to 2.5 KW output. Later this week the sun is due to make an extended appearance, so I will be looking for some good production days.

    Paul
  • Frxddy
    Frxddy Solar Expert Posts: 113 ✭✭✭✭
    Re: New 9.2 KW System

    Congrats on getting 'er up & running! Good looking system. I'm sure it'll serve you well.
  • TheBackRoads
    TheBackRoads Solar Expert Posts: 274 ✭✭
    Re: New 9.2 KW System

    Nice system!! How far is the array to your basement?
  • tecman
    tecman Registered Users Posts: 13
    Re: New 9.2 KW System
    Nice system!! How far is the array to your basement?

    It is about 120' to the house and another 35' inside to the inverter. 4 strings of 10 panels and I ran #10 on each string.

    paul
  • Slappy
    Slappy Solar Expert Posts: 251 ✭✭✭✭✭✭
    Re: New 9.2 KW System

    very nice...........congrats!
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: New 9.2 KW System

    very nice setup. glad you got it together in spite of the continual soaking.

    i do see 2 possible hangups in the pics, but it is difficult to tell if they will be a problem for you or not.

    the first is the high tension lines. shadows from the wires can throw your output off.

    the second is the trees as i can't tell how far out they were taken down.

    now all may be fine at present, but at different times of the year the sun's angle can be vastly different.

    as you found out, pvs still output something under adverse conditions, but that is still far off from the goal you want it to be under nice and sunny conditions. for the record, it's been rather bleak here too as the same systems have pretty much been a plague here too to one degree or another with these slow moving closed lows. one exception was that when irene went up the coast i was getting drenched by lee for what seemed weeks. i do hope this isn't a prelude to what this winter will be like.
  • tecman
    tecman Registered Users Posts: 13
    Re: New 9.2 KW System

    The lines are in the line of sight, but the shadow is so small to be insignificant. As for the tree line, I do lose a bit at the beginning/end of each day. To fully cleat would require a lot more trees be cut, which we felt was not acceptable. As a remediation, I wired the strings east to west. In this was I will lose one string at a time at sunrise/sunset and not compromise the whole array.

    paul
  • autoxsteve
    autoxsteve Solar Expert Posts: 114 ✭✭✭✭
    Re: New 9.2 KW System

    Nice system and welcome to the forum!