Solar panel myths: five common concerns about solar PV debunked

More than a million homes in the UK now have solar panels. They're a guaranteed way to use truly renewable electricity, but many people are not sure about whether to invest. Some are put off by uncertainty about costs, others believe the installation will be disruptive and many worry that solar panels will be tricky to maintain.

These were among the most common questions and concerns people had about getting solar panels, according to a government report in July 2021.

So we've looked at the biggest worries and consulted more than 2,000 solar panel owners to bring you the facts.

Ready for solar panels? See what owners think of the biggest solar panel brands.

1. Solar panel costs are too expensive

Solar panels aren't cheap, but their price has dropped dramatically over the past decade. They can be less expensive than other renewable technology, such as heat pumps, and achieve greater energy bill savings.

According to the latest data from MCS (the Microgeneration Certification Scheme, which certifies solar PV installers), the average cost of installing one kilowatt of solar panels in 2024 is around £1,950. 

The same data shows that the average cost for a solar PV installation in 2024 is around £9,125, which indicates that the average size of installation is around 4.7kW.

The cost to install solar panels at your home will depend on various factors, including:

• the size of the system
• the type of solar panels
• the type of building on which they'll be fitted.

Read more: Find out how much solar panels cost. We've worked with the Royal Institute of Chartered Surveyors and surveyed more than 1,000 solar panel owners to give you costs by system size, house type and electricity production.

Whether you feel that solar panels are 'too expensive' also depends on what you get in return. If you can afford them without needing to borrow (and pay interest), then your solar panels could pay for themselves in around 10 years – but this varies greatly. Find out whether solar panels are worth it for you.  

2. Solar panels aren't suitable for my home

Solar photovoltaic (PV) panels can be installed on a wide range of homes. We've heard from people installing solar panels on bungalows and terraces, as well as semi-detached and detached houses.

If your main house roof is unsuitable (a thatched roof, for example), solar panels can instead be installed on a garage or other outbuilding. And, contrary to popular belief, solar panels can be installed on flat roofs too.

The most important thing is the direction your roof faces. You'll need a mainly south-facing roof to get the best power output from solar panels. Southwest or southeast-facing are also good, though you may get slightly less power.

Also consider:

• How steep your roof is (around 30 degrees is best)
• Where you live (the southwest gets more sun than the north, for example)
• How many panels you'll have space for (more panels equal more power)
• Is your roof shaded? Any shade will affect solar panels' power output.

Solar panel installation is generally simpler if you own your home; however, if you're a leaseholder or in a shared-ownership property, you may be able to install solar PV with the permission of your freeholder or landlord.

Solar panels can be installed on blocks of flats, but this is often done by the landlord or freeholder. If you and your neighbours are keen, speak to the landlord or managing agent. 

If you live in a listed building, a conservation area or World Heritage Site, or other designated area, you may need planning permission for solar panels. Find out more about planning permission on our solar panel installation advice page.

Use Which? Trusted Traders to find a reliable solar panel installer near you. Our service is free, and all traders listed must pass our rigorous assessments.

3. Solar panel installation is disruptive

Imagining your house filled with mess from a lengthy installation could be enough to put you off considering solar panels.

But few owners complained to us about the installation being disruptive, and 80% said that they'd install solar panels again if they moved home.

Your installers will usually need to erect scaffolding to install solar panels on your roof. Once this is up, solar panels can be installed in a day or two.

The inverter will usually be fitted in either a loft or garage. This converts the DC your panels produce to AC that you can use in your home.

There will also be a generation meter, so you can see how much power your panels are producing.

Read more: our guide to solar panel installation.

4. There isn't enough sun for solar panels

Although the UK is not famously sunny, we do have enough sunlight for solar panels to work effectively.

Solar panels work during daylight, even when it's cloudy or overcast, as they use light6 not heat to generate energy. They don't need direct sunlight, although they'll produce the most electricity when it's sunny. 

Despite our reputation for grey weather, the UK receives around 60% of the solar radiation found at the equator – a similar amount of solar energy as parts of France, Spain and Germany. 

Cool and windy conditions can even be beneficial, since it can serve as a cooling mechanism for the PV modules, leading to increased efficiency.

Despite not needing sunshine, solar panels shouldn't be shaded. Check that any nearby trees or neighbouring buildings don't cast shadows onto your roof, and aren't likely to in the future.

5. Solar panel problems are common

Nearly seven in 10 solar panel owners we surveyed have had no technical problems with their solar panel system since it was installed.

Among those who did report a technical fault, inverter problems were by far the most common. Some 15% of owners in our survey reported an inverter problem.

Inverters have a shorter lifespan than solar panels, so you should expect to replace yours at some point.

Find out more about solar panel problems and how to solve them.

Which? solar panels research

In April 2024, we surveyed 2,039 Which? Connect panel members who have solar panels on their home.

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