alternative energy tutorials image
photovoltaic array image

Connecting Solar Panels Together





Please share/bookmark with:

How to Connect Solar Panels Together

solar powerConnecting solar panels together is a simple and effective way of increasing your solar power capabilities. Going green is a great idea, and as the sun is our ultimate power source, it makes sense to utilize this energy to power our homes. As solar power becomes more accessible, more and more homeowners are buying photovoltaic solar panels.

However, these photovoltaic solar panels can be very costly so buying them over time helps to spread the cost. But the problem then becomes how do we connect these extra solar panels together to increase the voltage and power output of what’s already there.

The trick here when connecting solar panels together is to choose a connection method that is going to give you the most energy efficient configuration for your particular requirements. Connecting solar panels together can seem like a daunting task when you first start to look at how it should be done, but connecting multiple solar panels together is not that hard with a little thought. Wiring solar panels together in either parallel or series combinations to make larger arrays is an often overlooked, yet completely essential part of any well designed solar power system.

There are three basic but very different ways of connecting solar panels together and each connection method is designed for a specific purpose. For example, to produce more output voltage or to produce more current. Solar panels can be wired in a series or parallel combination to increase the voltage or amperage respectively, or they can be wired together in both series and parallel to increase both the voltage and current output producing a higher wattage array.

Whether you are connecting two solar panels more more, as long as you understand the basic principles of how connecting multiple solar panels together increases power and how each of these wiring methods works, you can easily decide on how to wire your own panels together. After all connecting solar panels together correctly can greatly improve the efficiency of your solar system.

Connecting Solar Panels in Series

The first method we will look at for connecting solar panels together is what’s known as “Series Wiring“. Connecting solar panels together in series is used to increase the total system voltage. Solar panels in series are generally used when you have a grid connected inverter or charge controller that requires 24 volts or more. To series wire the panels together you connect the positive terminal to the negative terminal of each panel until you are left with a single positive and negative connection.

Solar panels in series add up or sum the voltages produced by each individual panel, giving the total output voltage of the array as shown.

Solar Panels in Series of Same Characteristics

connecting solar panels together in series

 

In this method ALL the solar panels are of the same type and power rating. The total voltage output becomes the sum of the voltage output of each panel. Using the same three 6 volt, 3.0 amp panels as above, we can see that when they are connected together in series, the array produces 18 volts (6 + 6 + 6) at 3.0 amps, or 54 watts (volts x amps).

Now lets look at connecting solar panels in series with different nominal voltages but with identical current ratings.

Solar Panels in Series of Different Voltages

solar panels in series with different voltages

 

In this method all the solar panels are of different types and power rating but have a common current rating. When they are connected together in series, the array produces 21 volts at 3.0 amps, or 63 watts. Again the amperage remains the same at 3.0 amps but the voltage output jumps to 21 volts (5 + 7 + 9) .

Finally, lets look at connecting solar panels in series with completely different nominal voltages and different current ratings.

Solar Panels in Series of Different Currents

solar panels in series with different currents

 

In this method all the solar panels are of different types and power rating. The individual panel voltages will add together as before, but this time the amperage will be limited to the value of the lowest panel in the series string, in this case 1 amp. Then the array will produce 19 volts (3 + 7 + 9) at 1.0 amp only, or only 19 watts out of a possible 69 watts available reducing the arrays efficiency.

We can see that the solar panel rated at 9 volts, 5 amps, will only use one fifth or 20% of its maximum current potential reducing its efficiency and wasting money on the purchase of this solar panel. Connecting solar panels in series with different current ratings should only be used provisionally, as the solar panel with the lowest rated current determines the current output of the whole array.

Connecting Solar Panels in Parallel

The next method we will look at of connecting solar panels together is what’s known as “Parallel Wiring“. Connecting solar panels together in parallel is used to boost the total system current and is the reverse of the series connection. By parallel wiring panels you connect all the positive terminals together (positive to positive) and all of the negative terminals together (negative to negative) until you are left with a single positive and negative connection to attach to your regulator and batteries.

When you connect solar panels together in parallel, the total voltage output remains the same as it would for a single panel, but the output current becomes the sum of the output of each panel as shown.

Solar Panels in Parallel of Same Characteristics

connecting solar panels together in parallel

 

In this method ALL the solar panels are of the same type and power rating. Using the same three 6 volt, 3.0 amp panels as above, the total output of the panels, when connected together in parallel, the voltage output would remain the same at 6 volts, but the amperage would increase to 9.0 amps (3 + 3 + 3), or 54 watts.

But what if our newly acquired solar panels are non-identical, how will this affect the other panels. We have seen that the currents add together, so no real problem there, just as long as the panel voltages are the same and the output voltage remains constant. Lets look at connecting solar panels in parallel with different nominal voltages and different current ratings.

Solar Panels in Parallel with Different Voltages and Currents

solar panels in parallel with different voltages and currents

 

Here the parallel currents add up as before but the voltage adjusts to the lowest value, in this case 3 volts. Solar panels must have the same output voltage to be useful in parallel. If one panel has a higher voltage it will supply the load current to the degree that its output voltage drops to that of the lower voltage panel.

We can see that the solar panel rated at 9 volts, 5 amps, will only operate at a maximum voltage of 3 volts as its operation is being influenced by the smaller panel, reducing its efficiency and wasting money on the purchase of this higher power solar panel. Connecting solar panels in parallel with different voltage ratings is not recommended as the solar panel with the lowest rated voltage determines the voltage output of the whole array.

Then when connecting solar panels together in parallel it is important that they ALL have the same nominal voltage value, but it is not necessary that they have the same ampere value.

Connecting solar panels together to form bigger arrays is not all that complicated. How many series or parallel strings of panels you make up per array depends on what amount of voltage and current you are aiming for. If you are designing a 12 volt battery charging system than parallel wiring is perfect. If you are looking at a higher voltage grid connected system, than you’re probably going to want to go with a series or series-parallel combination depending on the number of solar panels you have.

But for a simple reference in regards to how to connect solar panels together in either parallel or series wiring configurations, just remember that parallel wiring = more amperes, and series wiring = more voltage, and with the right type and combination of solar panels you can power just about any electrical device you may have in your home.

For more information about Connecting Solar Panels Together in either series or parallel combinations, or to obtain more information about the different types of solar panels available, or to explore the advantages and disadvantages of using solar power in your home, then Click Here to order your copy from Amazon today and learn more about designing, wiring and installing photovoltaic solar electric systems in your home.

Some high quality solar panels you may be interested in which can be connected together and used in solar arrays.


153 Comments » for Connecting Solar Panels Together
  1. Eric Koomson Eric Koomson says:

    am using 70w panel 12 v40ah battery, am using 12v solar tv 26w 2.6A and 14w 1A satelite decoder, all loads is 40w 3.6A, if i on the tv and the decoder on during day time my battery find it difficult to charge and i can’t get full charge, so i have to off all load to get fully charge before i can watch the tv in the evening for about 5-6hrs, i want to know to get full charge with my loads on during day time should i go for other panel to be added to the 70w panel am using and if yes how many watts of panel should i go for it to be added to the 70w to charge the 40ah battery

    • The proper charging and discharging of deep cycle batteries is important to maximize battery performance as both under- or over-charging batteries can significantly reduce battery life. The greater the state of discharge, the more the battery becomes weakened so discharge (called Depth of Charge) should not be more than 50%. Thus: (40Ah x 12V)/40W = 12 hrs x 50% = 6hrs, which is what your seeing.

      Charging deep cycle lead-acid batteries requires a constant current and voltage via your charge controller which your 70w panel may not be able to provide. Just because your panel is rated at 70 watts does not mean it will constantly generate 70 watts of power, as the amount of solar irradiance, sun hours, efficiency, etc. will all affect the output power. You may need additional wattage for what you need.

  2. shahzad ahmad shahzad ahmad says:

    hello sir how are you?i would like to ask that 2400 va solar inverter how many solar panel can be connected i mean how many watts 2400 watt panell can i connect with that .thank you .

  3. Shawn Shawn says:

    Good day. I have 4 panels( 40 watts a panel and 2.2 amps each) wired parallel. I got a panel for Christmas which is 100 watts and 5.8 amps All panels are rated at 17.1 volts. I got 4 6volt batteries and a 20 amp charge controller. How should I hook up the 100 watt panel to my system ? If possible?
    Thanks
    Shawn

  4. Kobby Prince. Kobby Prince. says:

    Hi, I need a little help on fixing my solar panels in Africa.
    I have twenty (20) of 100W solar panels.
    I also have ten (10) 12V 100Ah batteries
    I also have 2000W power inverter.
    And 12v/24v control board charger. I have more than 10 of the control board chargers.

    I have already done the connection but it seems it’s not able to power my freezer at home. All the professionals technicians are very very far from my home.

    Let me describe how I did my connections. I connected all the negative terminals on the solar panels together and the positive also together. So I have all eight (8) panels connecting to one control board and then all the eight (8) batteries to the control board charger also. And from the batteries to 2000W power in inverter. First I was able to use the freezer but not anymore. Any help on how to connect them properly. Do I need to use 3 control board chargers or just one is okay.

    Anyone with assistance who is willing to help me out can message me on.
    Thanks and God bless.

    • Michael Rock Michael Rock says:

      From your connection, the solar panels are connected in Parallel, this means that your wattage has not increased but your current has, from my experience doing solar, a 100 watts solar panel has about 4.7- 5.4 current. if i go by this number you have 100Watts, and about 4.7A * 20 = 94A. But for us to go further you have to provide me with some information.

      How many volts in your 2000w inverter 12V or 24V?
      What is the maximum Wattage input and Current(A) of your solar charge controllers?

  5. Innocent khelebeni Innocent khelebeni says:

    Hello
    I hope you will assist me with more information about my solar panels system I buy 2x95w solar panels, 2x12v sealed batteries,1000w modified 24v input inventor , 12 or 24 volt 20amp solar charge controller now my challenge is how to connect this system so that it can work my challenge are we don’t have any power in the house

    Please assist me with this situation

    • guillermo guillermo says:

      no matter if you connect PV in parallel or serie , that’s if you thing in final power , main thing is if Charge controller supports voltage Sum of PV as input , if it support you can connect : PV in serie as charge controller input Charge controller output to batteries and in parallel , the load if it is in 24 V , if not this output should be connected to inverter input (24 V input ) and load to de output inverter. take in acount that you have only 1000 W so you have to be sure about what or how many devices you will connect to your system.. hope this help you to solve your problem !

  6. Domingo Domingo says:

    Hello,
    I have 4 panels of 36V – 300W – 8.31A each. What kind of controler, inverter and batteries would I need to begin a system.

    • guillermo guillermo says:

      Main thing is what is the load (how many Watts) you want to connect to your system an how many hour it need to be working .This power will determinate your system , included if your PV are enought

    • Michael Rock Michael Rock says:

      If you have 300W, you can run a 1000 watts load using a 2000VA(24V) inverter, you will need 2 pcs of 200ah 12V Batteries, 24V 40/50A charge controller, with at least 1600W Max.PV Input (PWM or MPPT) your choice, and this system can power a 1000W load for around 9hrs if the batteries are fully charged. You will need to connect your panels in parallel. so you have 1200W for 33.24A. Here is the formular for calculating Battery bank or run time A= Load(W) * Hours / Voltage(system voltage which is 24 in this case) = AH (battery bank) thus: 1000*9/24 = 375AH approximetly 400AH, which is better as 200ah * 2.

Leave a Reply

Your email address will not be published. Required fields are marked *

*

What's the Answer *