The best angle and direction for solar panels in the UK

Your solar panel positioning can have a huge impact on your system’s output. It's crucial to get this right, so your panels have the best chance to soak up as much daylight as possible and generate more electricity for your home.

This article will touch on factors like latitude, tilt angles, roof orientation - and even alternative solutions for not-so-perfect setups.

Keep reading to find out more about the optimum way installers should position your solar panels.

If you’d like to find out how much a solar & battery system could save you, fill out a few quick questions below and we’ll generate an estimate for you.

Why is solar panel angle and orientation important?

Solar panels need daylight in order to produce electricity, and so it makes sense that your panels should be receiving as much daylight as possible. 

And given that the sun follows a very specific course through the sky, your panels need to be positioned in a very specific way. 

Consequently, the angle and direction of your solar panels will have a big impact on how much electricity they can produce. 

The angle of a solar panel refers to how many degrees of variance it is from horizontal, and the orientation of a solar panel refers to how many degrees of variance it is from south.

What’s the best angle for solar panels?

A solar panel’s angle is important because it determines how much daylight will strike its surface. The more direct the daylight, the higher the electricity output.

Generally speaking, the best angle for solar panels in the UK is about 35 degrees from horizontal, although this varies very slightly around the country. 

A study from 2021 revealed that the best angle for solar panels is typically somewhere between the latitude of the location and 15 degrees below that figure. In some places, the best angle will be exactly the same as the latitude, whereas in other locations the best angle will be closer to the latitude minus 15 degrees. 

For instance, the latitude of London is 51.5 degrees, but the optimum angle for solar panels in this city is 36 degrees. 

However, in the case of most rooftop solar panel installations, the angle of the solar panels is determined by the angle of the roof - there isn’t much you can do to change it.

Does the optimum angle change throughout the year?

The optimum angle for solar panels changes throughout the year because of the sun's shifting position relative to the Earth. 

During summer, the sun is higher in the sky, so it's better to angle the panel slightly flatter for maximum daylight absorption. But a steeper angle is needed in winter, when the sun is lower in the sky.

While it would be ideal to periodically adjust a solar panel’s tilt angle to match the sun's changing position, it's not practical for most solar panel systems, especially those on roofs. 

For some homeowners, the added complexity and cost might not be worth it - especially with the significant upfront cost of panels. Instead, somewhere around 35 degrees is the best compromise for maximum electricity generation throughout the year.

What’s the best direction for solar panels to face?

The orientation of a solar panel is important because, in any part of the world, the sun only occupies a part of the sky. 

For instance, in the northern hemisphere, the sun is in the southern part of the sky. And vice versa; in the southern hemisphere, the sun is in the northern part of the sky. 

Naturally, solar panels in the UK will work best when facing south, as it means they’re facing the sun. 

But if your roof doesn't allow for a southern exposure, east-west orientations can also work. Panels facing east will make more electricity in the morning, while those facing the west will generate more power in the afternoon and evening. 

However, if you only have space on your rooftop for north-facing solar panels, it’s normally not worth going ahead with the installation.

The orientation of a solar panel is also called its azimuth, which is the horizontal angle compared to true north (0 degrees).

What if you don’t have an angled roof for solar panels?

If you don't have an angled roof for solar panels, there are other options available - with varying levels of feasibility and effectiveness. Here are some examples of alternative strategies.

Ground-mounted solar panels

Ground-mounted solar panel installations offer several advantages but can be tricky to implement in the UK, particularly for residential properties.

As ground-mounted panels tend to have a higher power output, these systems are usually considered as small-scale commercial projects, even if they're intended for a single household's use. This means they need complex approvals like planning permission and Distribution Network Operator (DNO) approval.

The installation process itself may require specialised inverters, batteries, and equipment and expertise beyond a typical residential solar installer's capacity.

While offering flexibility in panel orientation, the challenges associated with approvals, paperwork and specialised installation requirements make ground-mounted systems less common compared to traditional rooftop installations.

Solar panels on a balcony

You can put vertical solar panels on balconies or their railings to generate electricity, but they won't be as effective as rooftop installations because they can't face the sun directly all day.

Even though they're not as efficient, vertical balcony solar panels are still a great way to get clean power in crowded cities where there's no room for normal solar panels.

For example, Germany had seven times more small registered systems at the start of 2023 compared to the previous year - apartment-dwellers can even buy small, subsidised plug-in solar systems at their local supermarket.

Solar panels on a flat roof

Homeowners with flat roofs used to need planning permission to install solar panels, but in December 2023 the government changed its 'permitted development' rules. This made it easier for more homes to have solar panels, including those with flat roofs.

Crucially, solar panels on a flat roof need a heavy ballasted mounting system to stay secure at the correct angle in high winds. However, a typical ballasted solar panel setup can weigh around 100kg per panel, compared to only around 20kg per panel for a non-ballasted system. If you were to install 10 solar panels on a flat roof, this could weigh over 1,000kg. 

The majority of residential flat roofs aren't strong enough to support heavy loads, and so a solar panel installation would be very unsafe. 

Therefore a residential flat roof solar panel installation is only really possible if the roof in question is very structurally secure.

This is why most flat roof installations in the UK are on commercial buildings, as these are a lot stronger.

Summary

The key to maximising your solar electricity production lies in strategic panel placement. The best spot for solar panels in the UK is a roof that faces south and has a tilt of about 35 degrees.

But remember, these are just general guidelines. Other factors - like shading from your immediate environment and your specific location - could affect where your installer can place your solar panels.

Ultimately, your best bet is to consult with a professional installer to find the right solution for your home.

To find out how much a solar & battery system could save you on your electricity bills, answer a few quick questions below and we’ll generate an estimate.

Best angle and direction for solar panels: FAQs