Should I connect my Solar Panels in Series or Parallel?


 A common question asked by many iTechworld customers:

"Can I join one of your 120W Solar Panels with my existing 200W Solar Panel on my roof to get 320W?"

Mixing and matching Solar Panels can be done. In order to get the results you are looking for though you must take all the factors into consideration beforehand. In this blog I will look at the different ways of connecting Solar Panels together to make an array. I will break down the basic fundamentals to give you an idea of what wattage you should expect from your array.

When you are looking to connect Solar Panels produced by different manufacturers together the problem does not come from different manufacturing styles or cell type, it comes from the electrical characteristics of the solar panels. Watts, Volts and AMPS.

There are two ways to wire up Solar Panels. Series and Parallel. Both have their own purpose and applications and both have different outcomes when hooking up Solar Panels of different wattage together.

Firstly lets take a look at connecting Solar Panels in series. Solar Panels are usually connected in series to obtain higher output voltage. This is usually the case with 24v systems.

If we connect 4 x 150w Solar Panels in series the total power is calculated as follows:


 Total power = 150W + 150W + 150W + 150W = 600W


However if we were trying to create 620watts of power using different wattage solar panels we would have a different outcome.



Total Connected Power = 140W + 160w + 160w + 160W = 560W


The 140W Panel actually drags the 3 other 160W panel’s wattage down to 140W as well meaning we effectively have 4 x 140W Solar Panels.

So when connecting Solar Panels in series always try to keep the electrical properties of the solar panels identical to get the full benefit of the solar array.

Now lets look at connecting Solar Panels in Parallel. Solar Panels are connected in parallel to obtain higher output current. More AMPS. This is usually used with 12v set ups.

 For Solar Panels connected in parallel total power is calculated as follows:

 Total connected power = 140W + 150W + 150W + 150W = 590W

Unlike Solar Panels connected in series, the different Wattage parameters do not effect the overall outcome of the array. However if the voltages of the Solar Panels are drastically different then this can cause some discrepancies.

With this knowledge it should stand you in good stead when you are looking to expand your Solar array on your caravan, motor-home, boat and RV.

The great thing about blog entries is that its just the start of the conversation, do you have anything to add? Do you have a question about the information provided? Have your say in the comments section below.

Click the following link to view our range of solar panel kits.


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