Make the most of your solar panels

Cutting your electricity bills and your carbon footprint are two of the biggest reasons people choose to install solar panels. How you use your solar panels is key to doing both.

Our tips – gathered from experienced solar panel owners and experts – will help you maximise the benefits of solar panels.

Plus, we reveal the answers to common questions about maintaining, cleaning and using your solar panels.

If you have an issue with your system, find out more about solar panel problems and how to solve them. 

How can I maximise profit from my solar panels?

Once you've invested in solar panels, make the most of them by using as much of the free renewable electricity they generate as possible.

Compare the price you pay for electricity from your energy supplier with the amount you are paid for exporting your excess solar electricity to the grid. This shows you how much you could save on your bills.

To get paid for exporting solar electricity, you'll need to sign up for the Smart Energy Guarantee. If you have had solar panels for a few years, you might receive feed-in tariff (FIT) payments instead.

Solar panels typically produce most electricity during the daytime in summer when it's sunny. 

Which? members should log in to read experienced solar panel owners' tips on how to use more of their solar electricity, including what to do if you're not at home when your panels are generating.

If you're not a member you can join Which? for more solar panel insights, including our solar panel owners' solar panel brand reviews.

Do solar panels need cleaning?

Not always. Solar PV panels should be self-cleaning, especially if your roof has the right incline. An occasional heavy rain shower should be enough to clean them.

However, if the following are true of your system and you've noticed a drop in power, then you might find that a deeper clean will get them working at full capacity:

• Birds regularly roost on your roof and soil your panels.
• Trees drop leaves or pollen onto them.
• Salt builds up on your panels because you live near the sea.
• Inner-city traffic pollution creates a film on your panels.

Monitor how much your solar system generates. If you see an unusual drop, check with your installer what the reason could be. It might be that your panels need cleaning, but it could be something else.

Can I clean my solar panels myself?

If your panels have built-up dirt that natural rainfall isn't removing, and you think it’s affecting how much electricity they generate, consider your options for cleaning.

It’s possible to clean your own panels and solar panel cleaning kits are available online and from some hardware stores, costing £50-£100. If you're planning to clean them yourself, follow these tips:

• Look for a kit with an extendable pole so you can clean them safely from the ground.
• Check with the manufacturer that the kit is suitable for your panels.
• Only use water to clear your solar panels. Detergents or abrasive materials could harm their surface.

But there are also many companies offering solar panel cleaning services, including solar installers. Speak to a couple of companies and get quotes so you know the going rate in your area before you commit.

Will I need to replace the solar panel inverter?

Probably, yes. Solar panels often have warranties for 20-25 years, but their inverters aren't expected to last as long as the panels themselves.

Which? members can log in (or you can join Which?) to find out how often you should expect to replace your inverter and how much it'll cost.

What happens if my solar panels are shaded?

Shade is bad news for solar PV panels, so watch out for chimneys and trees. 

Over the 25 or more years you will have the panels, young trees may grow to shadow them. Even if just one panel is in the shade, the whole system’s performance may be hampered.

Which? members can log in (or you can join Which?) to find out what to ask your installer about shade and what to do if your neighbour's tree shades your solar panels.

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