Shading

[jag1972]

I am looking to have a 4kW system installed in two row.
Top row should be completely shade free, bottom row is split five and three panels with a chimeny inbetween which will have shading over parts of the five panels in the AM and over parts of the three panels in the PM.
I have been quotes for Suntech 250w panels, Sharp 250w panels and BLD 250w panels (all on a Fronius inverter). Does anyone have any advice on the best way forward in terms of which panels perform best under these conditions and any particualr measures I should ensure that the installers are taking?

Thanks

 

[SolarCity]

With a chimeny creating shadows on the lower rows, I'd strongly recommend using an inverter with dual MPP tracking - SB4000TL or Power One 3600 would probably be a better option than Fronius in this instance.

 

[jag1972]

Thanks Biggs. Any thoughts on the panels? Also, do the Suntechs have bypass diodes?

 

[jag1972]

The installer has suggested that connecting the 16 panels in a single string through the Fronius MPPT, combined with the bypass diodes in the panels should overcome the issue of the single MPPT. Would this be correct?

 

[SolarCity]

If you post a picture of your roof and let me know what kind of orientation you are at I should be able to give you a better idea. Bypass diodes will not overcome the issue of a single MPPT and if the roof receives shading throughout the year (which it probably will with a chimney), then it really needs some careful design work.
My thoughts on the panels are - go for the Suntech, if your installer can get them/