Just completed and got approval to operate my 15.3kw system. Used the following:
24 550w panels, installed in 6 rows of 4 (landscape in a 10° East/west configuration).
6 400w panels (on angled roof, so did use flashing and rails)
30 Tigo inverters
1 10kw growatt inverter, & 1 6kw growatt inverter
Solar Stack 10° mounting pedestals (with roof adhesive) for flat roof (no roof penetrations)
Total equipment cost= $17k (using 2 inverters increased my average cost per KWh)
Installation = $8k (did have to add subpanel to make room for the solar, so that added cost)
Total~$25k.
Production for now is about 31kw/day on average with a high so far of 43kw on all sunny day in the dead of winter and low of 11kw on a rainy day
Conclusion:
I think I overpaid for panels as now I could get them for $3k cheaper (32c/kw instead of 51c/kw). Definitely overpaid for the small things as well such as extra PV wire, the flashing and rails for the 6 panels mounted on the angled part of the roof. The flashings are basic designs. They should be made for $1 a piece, not $15. Same for the Solar stack mounts. These are basic aluminum extrusions. Like a $1/kg from china, but these were made in the US and already had regulatory approval, so using those was an extra $1.5k.
The installation took too long too as I should have had them plan the wiring better. The installers had to lift the panels 2-3 times to install or reinstall and attach the wires to keep them off of the roof. Either that or they could have preinstalled the tigo optimizers so that they only had to connect the panels together. Also mounting the conduit also took much too long. There should be a quicker way to do that. Anyone have any suggestions on that? We use all metal conduit, and had to bend it to make it work. Should have been quick, it was not.
I think one could have installed the solar panels and all of the wiring for them on the roof as a DIY project, and had an electrician handle the inverters and connection to the electric panel. Could have saved another $4k, but I think that was worth paying for. If I was doing it again, I'd use a single 11.4kw inverter and only install 11-12kw in panels. Could get away with a 10kw inverter and use solarapp+ if necessary for the application. Approval would be a lot quicker. Overall $1.63/kw installed is not bad.
24 550w panels, installed in 6 rows of 4 (landscape in a 10° East/west configuration).
6 400w panels (on angled roof, so did use flashing and rails)
30 Tigo inverters
1 10kw growatt inverter, & 1 6kw growatt inverter
Solar Stack 10° mounting pedestals (with roof adhesive) for flat roof (no roof penetrations)
Total equipment cost= $17k (using 2 inverters increased my average cost per KWh)
Installation = $8k (did have to add subpanel to make room for the solar, so that added cost)
Total~$25k.
Production for now is about 31kw/day on average with a high so far of 43kw on all sunny day in the dead of winter and low of 11kw on a rainy day
Conclusion:
I think I overpaid for panels as now I could get them for $3k cheaper (32c/kw instead of 51c/kw). Definitely overpaid for the small things as well such as extra PV wire, the flashing and rails for the 6 panels mounted on the angled part of the roof. The flashings are basic designs. They should be made for $1 a piece, not $15. Same for the Solar stack mounts. These are basic aluminum extrusions. Like a $1/kg from china, but these were made in the US and already had regulatory approval, so using those was an extra $1.5k.
The installation took too long too as I should have had them plan the wiring better. The installers had to lift the panels 2-3 times to install or reinstall and attach the wires to keep them off of the roof. Either that or they could have preinstalled the tigo optimizers so that they only had to connect the panels together. Also mounting the conduit also took much too long. There should be a quicker way to do that. Anyone have any suggestions on that? We use all metal conduit, and had to bend it to make it work. Should have been quick, it was not.
I think one could have installed the solar panels and all of the wiring for them on the roof as a DIY project, and had an electrician handle the inverters and connection to the electric panel. Could have saved another $4k, but I think that was worth paying for. If I was doing it again, I'd use a single 11.4kw inverter and only install 11-12kw in panels. Could get away with a 10kw inverter and use solarapp+ if necessary for the application. Approval would be a lot quicker. Overall $1.63/kw installed is not bad.
