☀️ Solar panels connected in series produce more energy in ideal conditions.

☀️ Solar panels connected in parallel are better protected against obstructions.

☀️ Most solar panel systems feature both types of connections.

Solar panels are becoming more affordable every day, so now is a great time to switch to solar power – but before you can enjoy free, clean electricity, your installer will determine how to wire your solar panels in series, in parallel, or both.

In this blog post, I’ll explain how series and parallel solar panel connections differ, the advantages and disadvantages of each, and why your installer may suggest a combination of the two different types of connections.

If you want to get your own solar panel system installed, we can help you with a free no-obligation quote and solar PV system design tailored to your individual energy requirements, just ‘Contact‘ us to start your solar journey today!

What does it mean to install your solar panels in series or parallel?

Solar panels can be connected to each other in two different ways: series and parallel.

Each solar panel has a positive and negative terminal, similar to the batteries you use at home, and the way they’re connected determines whether your system is in series or parallel.

A series connection is when you wire the positive terminal of one panel to the negative terminal of another. This boosts the system’s total voltage – and thus its output – while keeping the amperage the same as one panel.

Parallel connections are the opposite – they involve wiring all the positive terminals together, and all the negative terminals together. This will keep the system’s voltage low, while raising its amperage.

A series connection is more vulnerable to disruptions – for example if something shades your solar array – which will reduce the energy production of every panel in the system.

On the other hand, panels in a parallel connection will work independently of each other, regardless of what happens to the rest of the system.

Imagine you’ve hung up a string of fairy lights. If one bulb suddenly goes out and they’re wired in parallel, the other lights will remain on – but if they’re in series, they’ll all go out.

It’s also fairly common to use a mix of series and parallel connections, to make sure your system reaches the optimal voltage and amperage without overloading your inverter.

It’s essential your installer chooses the right way to connect your panels, as the wiring method will have a huge impact on how much electricity they generate.

Why would you install your solar panels in series?

Solar Panels in Series Pros

  • Produces more energy than in parallel
  • Makes the most of any and all daylight
  • Lower amperage means lighter and cheaper cables

Solar Panels in Series Cons

  • Shade can severely affect the output

A series connection can boost the system’s output if your solar panels are not blocked by anything.

The high voltage will usually produce more solar energy at all times of day, which means you can use the low light in the early morning or at dusk, as well as when the sun is bright.

A series connection also helps your system to match a powerful inverter’s voltage needs – and if you have too many panels for the inverter, you can wire the extra panels in series separately, then connect them in parallel.

However, your output will drop significantly if a single panel is shaded by a stray breeze moving a tree.

Why would you install your solar panels in parallel?

Solar Panels in Parallel Pros

  • If one panel’s obstructed, the others will continue working normally
  • Occasional shade won’t slash your output
  • You can use a less powerful solar inverter

Solar Panels in Parallel Cons

  • Produces more energy than in series
  • Higher amperage means heavier, more expensive cables

A parallel connection could work well if some of your solar panel system is often shaded.

Parallel wiring means the other panels will function normally if one of your panels is blocked.

A parallel connection also raises the amperage without increasing the voltage, which is good if your inverter can’t deal with a high voltage.

How will installing your solar panels in series or parallel affect your savings?

A series connection will produce more energy and save you more money, if your system is always clear of shade.

But if your panels are often in the shadow, the situation is different.

Then you’ll want to wire your system in parallel, which will make sure all your unshaded panels keep making the same amount of energy.

The choice between a series and parallel connection can mean hundreds of pounds in savings, depending on how bad your shade problem is.

Are solar panels installed in the UK usually in series or parallel?

Most solar panel systems use a combination of series and parallel connections.

Your solar panel installer will usually suggest splitting your panels into two groups, connecting each group in series, then wiring them in parallel.

This is because most roofs are free of overhead obstacles like trees, so you can benefit from the higher output that panels in series can generate.

The parallel connection between the two sets of panels is meant to safeguard you against any unexpected issues, like a loft extension on your neighbour’s house that casts shade on your panels for part of each day.

Using both series and parallel connections also lets you boost the voltage and amperage at the same time, enabling you to produce the most energy possible.

Should you install your solar panels in series or parallel?

The best option for your solar panels is to wire them in series and parallel.

This will help you match the highest voltage and amperage that your inverter can handle, and thus generate the most solar energy.

But if your panels will be shaded often, you may prefer to wire your solar panels in parallel only.

Or if you have few panels and they won’t be in shade at all, you may choose to wire them in series only.


You now have all the knowledge you need to discuss with your installer about their choice to wire your solar panels in series, in parallel, or both.

But in the end, you should mainly follow your installer’s advice.

If you want to find a solar panel installer who can help you make the best decision for your home, the best first step is to get multiple quotes.

NXTGEN Energy are MCS Certified Solar PV and Battery Storage Installers

Remember not all Solar Panel Installers are MCS Certified! NXTGEN Energy Ltd. are proud to be both MCS Certified Solar PV (Panel) Installers and also MCS Certified Battery Storage Installers. We are 1 of only 10 Solar Installers in Essex who are certified on both Solar PV and Battery Storage. This means we can install your complete Solar PV System to the high quality, performance, and safety as required by MCS Certification in the UK. Have you checked your installer on mcscertified.com?

If you are thinking of installing solar panels, solar battery storage or both, contact us here at NXTGEN Energy for a free no-obligation quote and solar PV system design on 01268 928 690, email: info@nxtgen.ltd or by clicking on the ‘Enquire Now’ button below. Think Solar? Think NXTGEN Energy!

NXTGEN Energy – Your Trusted Solar Energy Solutions Partner 💚

Frequently Asked Questions about Solar Panels in Series or Parallel

Is it better to run solar panels in series or parallel?

Wiring solar panels in series and parallel is usually the best option. If you have two groups of panels connected in series and wire them with parallel wiring, you can reach the highest voltage and amperage possible – which means making as much solar energy as you can. And if one group of panels is shaded at any point, the other group will keep working as usual.

What charges faster, solar panels in series or parallel?

Solar panels in series make energy faster than panels in parallel, when the sun is bright. But if something blocks your panels from the sun – like a tree branch – parallel wiring is better, as each panel will keep making energy no matter what happens to the others. Panels in series, however, can only make as much energy as the weakest panel in the system.

What are the disadvantages of installing solar panels in series?

Connecting solar panels in series has a big downside: if even a tiny bit of shade falls on them, their energy output gets seriously messed up. Imagine one pesky tree or branch blocking the sun and ruining all your electricity generation! But don’t worry, there’s a way to fix this problem. By using a mix of series and parallel connections in your solar panel system, you can avoid this issue altogether.

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