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Optimal configuration of non-identical panels

NinjaDeathMonk

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Sep 20, 2019
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Hello, everyone. Is there an optimal configuration of non-identical panels? Say I have two Goal Zero Boulder 100 Watt panels but I want to get two additional RICH SOLAR 100 Watt panels. If the charge controller requires that I have two in parallel and two in series to get the most power out of them, do I have to put the identical ones in series or parallel?

Goal Zero Boulder 100 Watt Monocrystalline Solar Panel
  • Optimum Operating Voltage (Vmp): 17.2V
  • Open-Circuit Voltage (Voc): 21.5V
  • Optimum Operating Current (Imp): 5.82A
  • Short-Circuit Current (Isc): 6.18A
RICH SOLAR 100 Watt Polycrystalline Solar Panel
  • Optimum Operating Voltage (Vmp): 17.8V
  • Open-Circuit Voltage (Voc): 21.2V
  • Optimum Operating Current (Imp): 5.62A
  • Short-Circuit Current (Isc): 6.02A

I guess in this example there is minimal difference but I am a stickler. Thanks.
 
The current available from panels in series is determined by lowest performing panel. If you paired a 5.62A and a 5.82A panel the rating would become 5.62A for the string.

A MPPT controller will seek the voltage that gives the maximum wattage for an array. As a panel (or string of) is pulled away from Vmp power production reduces. The drop in production is Vmp - present voltage * current.

Pulling a panel from 17.8v to 17.2v will result in little loss. Cutting paper current by 200mA results in a little more loss.

My vote would be to pair the panels by brand. Goal Zero in one string, Rich Solar in the other, then parallel those sets.
 
Sticklery you have 2 sets of identical panels so i would series connect the 2 identical panels then parallel connect the 2 sets but if you are a little ocd then test output doing it the other way.
Those 2 panels specs are very close. Probably no real life difference.
 
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