Solar Panel Series vs Parallel

If you’re just starting to learn how to utilize solar energy for your home, RV, or off-grid cabin, the technical terms can quickly become overwhelming. One topic that may cause confusion is solar panel series vs parallel wiring and which option is best for your needs.

How your solar panels are wired impacts your system's performance significantly. With the right solar panel series vs parallel setup, you can ensure your system is optimized for your specific situation, providing the best possible return on your investment.

There are two possible ways you can wire solar panels: series parallel solar panels. Both types of wiring have pros and cons, and hopefully, by the end of reading this article, you’ll be able to determine which one is the best for your requirements. 

💡 Key Terms to Remember

• Voltage - refers to the difference in electric potential (charge) between two points
• Current - it is the rate of charge (amount of electricity) that is flowing through a circuit
• Amperage - it is the unit used to measure electric current
• Output Voltage - this is the voltage that is released by a device, such as a generator or a voltage regulator
• Output Current - this refers to the maximum current that can be supplied to a load

Solar Panels Wired in Series

When examining a solar panel, you’ll notice two terminals—one positive and one negative. In a solar panel series vs parallel setup, wiring panels in series means connecting the positive terminal of one panel to the negative terminal of the next.

Again, remember, when you connect your solar panels like this, the amperage remains the same, but the voltage adds together. For example, if you connect in series two solar panels that have a rated voltage of 20 volts and a rated amperage of 5 amps, this two-panel string will have 40 volts but the output current would still be 5 amps. 

Having low amperage means you can use fewer cables and smaller gauge wires, which are more cost-friendly. (Further Reading: Electrical Wire 101) 

It’s also important to note that with this type of connection, you will have to use a Maximum Power Point Tracking or MPPT charge controller. This is because this type of charge controller can accept a higher voltage input and still optimize charging 12V (or more) batteries. 

Wiring solar panels in series is great for unshaded conditions and/or if you require a low-amperage system. 

Pros and Cons of Wiring in Series

Pros 

• Easier to work on and will not require additional equipment
• Keeps current low, so only small gauge wire is needed (less expensive)
• Optimal output is during the beginning and end of the day

Cons

• Every panel is critical in a series connection, which means even when a single panel is shaded, the system’s power output declines

Solar Panels Wired in Parallel

If the wiring in series is connecting a positive terminal of a panel to the negative of another, setting up your system in parallel means connecting both positive terminals of two panels and connecting the negatives of each panel.   

Wiring in parallel would lead to an increased amperage with the voltage remaining the same. So with our example above, the two-panel string will form 10 amps, but the system would still have 20 volts. 

Connecting in parallel will enable your solar panels to produce energy without going over the operating voltage limit of the generator’s inverter. Note that Pulse Width Modulation or PWM charge controllers are used with this type of wiring. 

Pros and Cons of Wiring in Parallel

Pros 

• Works well in shaded or mix-light conditions - the solar panels will continue to work optimally even if a solar panel gets shaded
• Panels will charge faster if they are connected in parallel 

Cons

• Will require additional supplies (e.g. branch connectors) and equipment with a higher current rate
• Since the amperage increases, you will require a thicker and more expensive wire 
• Doesn’t work well at the beginning or end of the day

Can you combine series and parallel solar panels?

Yes, in some cases, a series-parallel combination of solar panels is used, especially for large solar arrays. On the contrary, this type of connection is uncommon for small residential loads.

Which is better: Solar Panels in Series or Parallel?

When deciding what type of configuration is best, the ultimate question that you should answer is if a series or a parallel connection will provide you with the optimal energy to meet your requirements. 

You can choose to connect your solar panels in series if you need a low-amp solar system and if your panels remain under the sun for most of the day. On the other hand, if you want a low-voltage system or if you live in an area with mixed-light conditions (then you want to have your solar panels operate independently) connecting in parallel is the better option. 

Expandable Solar Generators

Having the ability to expand your solar system is a huge advantage. If you’re looking for eco-friendly generators that allow you to be versatile and harness more power as your energy needs grow, then you can check our solar generators at Nature’s Generator. 

With the Powerhouse system, you can connect solar panels, wind turbines, power pods, and more so you can customize your eco-system to fit your needs. 

If you choose to use Nature’s Generators, upgrading your eco-system wouldn’t be so daunting since all the necessary connectors and wires are already included in our power add-on bundles. Our reliable support team is also always ready to attend to you if you have questions about connecting your Power Panels or other concerns about your solar generator. 

Want to know more about our solar generators? Get in touch with us today!

 * We want to give credit where credit is due. Professional writer, Ishna Sablaya, contributed research and content to this blog titled: Solar Panel Series vs Parallel Thank you, Ishna, for your contributions!