Mixing the tilt angle in a pv string. Will the less optimal panels cancel the increase of the properly angled PV modules out?

[Joe_]

I have a string of 14 panels 7 series 2P that I am planning the mounting of presently. 10 will be mounted 3 degrees tilted east for drainage. ( I understand that this is less than ideal but it's how they will be mounted). The remaining 4 of that string are in a place that they could be mounted at an optimal angle facing south. 45 degrees for winter or 10 degrees for spring and fall or perhaps a adjustable mount..... Or for much less labor and less $, mounted at a lesser 3-5 degrees angle facing south. Similar to how the other 10 panels are mounted only pointed south instead of east.

My question is because the 10 almost flat mounted panels produce less than would the 4 properly angled panels would those 10 panels drag the greater potential output of the 4 better angled panels down nullifying the increase in output of those 4 panels. Or would the 4 panels boost the strings performance by whatever amount more they produce when properly pointed? Or would the output be somewhere in the middle?

 

[sunshine_eggo]

I have a string of 14 panels that I am planning the mounting of presently. 10 will be mounted 3 degrees tilted east for drainage. ( I understand that this is less than ideal). The remaining 4 are in a place that they could be mounted at an optimal angle facing south. 45 degrees for winter or 10 degrees for spring and fall or perhaps a adjustable mount..... Or for much less labor and less $, mounted at a lesser 3-5 degrees angle facing south. Similar to how the other 10 panels are mounted only they are facing east.

My question is because the 10 almost flat mounted panels produce less than would the 4 properly angled panels would those 10 panels drag the output of the 4 panels down and cause the total string not to produce enough power to justify the expense and effort of building the more complex mounts? Or would the 4 panels boost the strings performance by whatever amount more they would produce when properly pointed? Or would the output be somewhere in the middle?

For all panels in a single series string, the string will be limited to the power produce by the lowest yielding panel, thus the panels should be facing in the same direction. Light gives voltage. Intensity of light gives amps. All panels in a single string MUST pass the same current, and it will be the dictated by the panel producing the lowest current.

In other words, favorably oriented panels will be reduced to the power level produced by unfavorably oriented panels.

Specifically to your situation, in the morning, where you would expect your slightly East panels to perform well, they will produce the same per-panel power as your 4 South facing panels (lower). At high noon, where you expect your 4 South facing panels to perform well, they will produce the same per-panel power as the East array (lower).

 

[Joe_]

Thank you. That's what I wanted to know.