The options to wire various solar panels in a system are either series or parallel. It is important to understand these two configurations as we have to estimate our home needs or power storage for the future. Today let us compare connecting solar panels in series vs. parallel in detail.
How Connecting Solar Panels in Series Vs Parallel Differs?
Connecting PV panels in series increases the voltage but amps remain the same, but in parallel connection, current and power output increase.
For connecting panels in either series or parallel, we need to start with wiring. Any PV panel will have male and female MC4 connectors, i.e. positive and negative terminals. Differences between the connections are given below:
Series Connection | Parallel Connection |
Current flow is from positive to negative poles | Flow is from positive to positive and negative to negative poles |
These heap up voltage and carry on the same amperage | This connection rises on the amperage and continues the same voltage |
Even one malfunctioned panel troubles the whole array | Array works even if one panel has malfunctioned |
They can be preferred by high output panels as long as they don’t overload | Not preferred for high-rise output panels |
Connecting Solar Panels in Series
A series connection of panels means batching of panels in a line in order of positive to negative. So, the solar array voltage increases but amperage remains the same.
Below are the steps for this connection:
Step 1: Determine the voltage of the inverter, and estimate the power that generates so you can store it for future requirements.
Step 2: To set up panels, calculate the space, either it is a rooftop or the roof of a van, and put them one after another in a line. Check for any faulty panels in a series that may disturb the whole connection.
Step 3: Wiring solar panels in a series is so simple, just connect the first panel’s MC4 connector to the second connector’s negative terminal. Repeat this process with the remaining panels. At last two terminals are left unconnected at both ends, positive in the first panel and negative in the last panel, which are further linked to a charge controller.
Step 4: Link this setup to an inverter that transforms the sun’s energy from direct current to AC(alternate current).
Also, check out How to Wire Solar Panels to Inverter.
Now solar energy is ready to use for household appliances.
Connecting Solar Panels in Parallel
Here are a few ways to connect panels in parallel connections:
A. Connecting 2 Solar Panels:
For panels with similar voltage, connecting will be a simple task, as you can link the positive terminal to the positive and the same for the negative.
Step 1: Select panels and place them beside each other under abundant sunlight.
Step 2: Prepare the suitable wiring or cables for the panel.
Step 3: Use a junction box, and join wires that are positive with to male MC4 branch connector.
Step 4: Now link the negative wires using a plug to the female MC4 branch combiner.
Step 5: Now, the left-out negative terminal of this array should be connected to the negative of the PV terminal of the solar charge controller
Step 6: The positive end of the setup is linked with the positive terminal of the charge controller.
Now, the panels are ready for power generation and transmission to your needs.
B. Connecting 3 or More Solar Panels:
Step 1: For this type of connection link positive terminals of panels 1 and 2 and with panel 3.
Step 2: Connect negative terminals of panel 1 and 2 and further to panel 3
Step 3: Now connect the end wires to the controller
Step 4: If 4 panels need to be connected, attach from panel 3 to panel 4, and end wires to the solar controller.
C. Connecting with Different Powers:
Note that if you have PV panels with different wattages and voltages then a parallel connection cannot happen. The panel with the least voltage behaves like drag and would absorb current.
Think that you have 3 panels, but if we have two panels with the same voltage, the one with higher can be used for parallel connection. For example, there are 3 panels for the connection, two panels are 12V and one panel is 24V, you can link 12V together in series and go for a parallel connection to the 24V panel.
Note: Be careful with wiring, take proper safety measures, and if needed go for expert guidance.
Also See: How to Connect a DC Fan to a Solar Panel
Do Solar Panels Charge Faster in Series or Parallel?
When connected in series the battery charges fast rather than parallel. This happens because when connected in series the voltage is increased, which allows more current to flow. For example, when 2V batteries are connected in series, the voltage in total is 4V.
When connected in parallel, the charge will flow evenly among batteries as there is no voltage restriction, but this implies that the charge has a slower rate when compared to the series.
Does Solar Wattage Increase in Parallel or Series?
Wattage means the product of voltage and amperage. In a solar array, wattage increases in a series panel setup. This happens because a larger voltage is generated by adding the voltage of each panel leading to a spike of power and current.
Connecting panels in parallel will not increase the wattage. Instead, this setup can increase the amperage hours available.
Also Read: What Size Solar Panel to Charge 12V Battery?
Do I Need Diodes for Solar Panels in Parallel and Series?
Yes, diodes are necessary to sustain the voltage stability of the panels. For a series connection of panels, a bypass diode is preferable. When liked with a bypass diode the current chooses an alternative path which further provides continuity even if there is a fault in connection.
For a parallel connection blocking diodes are linked with branch connectors. Thus diodes are needed because the batteries should not be discharged over the panels.
We have learned, how to wire and connect solar panels in series vs. parallel under different conditions. Ultimately, for faster charging of the battery, it is better to connect the panels in series rather than parallel. Also, you must take proper safety measures to prevent any injuries or electrocutions.
Recommended: Solar Panel Energy Efficiency and Degradation Over Time