Why series connection?

Discussion in 'Solar Power' started by stevec, Jun 26, 2014.

  1. stevec

    stevec Funster

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    Can someone tell me why some people connect up solar panels in series instead of in parallel? Is there some technical reason. Wouldn't it be wasting volts but give only current as for a single panel. Whereas parallel connection gives double the current. Does it depend on the type of controller used (PWM or MPPT)?
     
  2. DBK

    DBK Funster

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    Possibly because the panels give different voltages?
     
  3. SomeoneElse

    SomeoneElse Funster

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    Energy lost in the cables is dependent on current not voltage. Doubling the current increases the power loss four fold.
    The controller must be suitable, older PWM controllers are dumb and use power from the panel at a fixed voltage typically 17V. Whereas a MPPT controller will find the best power point over its range. Always look at the maximum PV voltage of a controller its usually 100 to 150 volts. Using the open circuit voltage of the panels will allow you to determine how many panels can be connected in series. Make sure you don't exceed the maximum wattage that can be connected to a particular controller.
     
  4. cmcardle75

    cmcardle75 Read Only Funster

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    It is because like all power transfer systems, it is much more efficient to use higher voltages than higher currents. However, it does require a controller that can handle it. This would typically be an MPPT type that permits high input voltages.
     
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