Where Should You Put Solar Panels?

The location of your solar panels significantly impacts their efficiency and the energy they generate. In turn, this impacts your costs and savings. 

So where exactly is the best place to put solar panels? Our guide will consider the various options for solar panel placement and how these affect power output. 

Factors to Consider When Choosing Solar Panel Placement

Before we dig into the specific placement options, it’s a good idea to have an understanding of the main factors that influence the ideal location for solar panels. Each factor will vary from home to home, which is why recommendations for placement will vary. 

1. Sunlight exposure – The job of a solar panel is to absorb sunlight. So, the primary consideration for panel placement is how much direct sunlight the location will receive throughout the day. 
   
   With the UK being in the northern hemisphere, we see the sun rise in the east and set in the west. This means a south-facing solar panel will receive the most sunlight. It’s not the only configuration of course. South-east and south-west orientations can also be effective and will capture around 80% sunlight compared to south facing. 
   
   Although not ideal, even north facing panels will still produce electricity, albeit around 50-60% of a south-facing panel.
2. Shading – Shading reduces a solar panel’s efficiency. This can come from nearby buildings, trees and chimneys. Even partial shading can have a significant impact.
   
   Just how much of an impact shading has depends on whether your panels are connected in series or parallel. 
   
   A series connection, sometimes called a string, means the panels are connected a bit like a chain with one cable coming out of the end. These connections are vulnerable to shading. If one panel is in shade, it affects the output of the whole string. Parallel connections are more resilient to partial shading issues.  
   
   The use of microinverters also helps to avoid shading issues, as each panel independently sends its energy into the system.
3. Roof pitch – Solar panel performance can be impacted by the roof pitch, which alters the total amount of sunlight a panel can absorb. In theory you can use all types of pitches from a 0^o flat roof to a 50^o steep slope – solar panels can even be installed on gable end walls at a 90^o angle!
   
   However, these different angles will result in different efficiencies. It’s thought the optimal roof pitch to absorb most sunlight is 30-40^o. 
4. Available space – The amount of unobstructed space available will influence the size and number of panels you can install. If you’re installing panels on your roof, items such as roof windows and chimney stacks will reduce the area available. 

5. Local regulations – Check local planning permissions and building regulations, as these may affect where you can place solar panels. Some areas, such as conservation zones, may have specific requirements or restrictions.

With these factors in mind, let’s take a look at the most common places for installing solar panels. 

Sloped roof installation

Sloped roof installation is the most common option for residential solar panels in the UK. And for good reason. 

With a sloped roof, you have plenty of unused space that serves no other real purpose – aside from its main job to keep the weather out! 

The ideal orientation for solar panels on a roof is south-facing. These roofs receive the most sunlight throughout the day. However, homeowners shouldn’t be discouraged if their roof doesn’t face directly south. South-east and south-west facing roofs can also be suitable locations for solar panels, usually generating at least 80% of the energy a south-facing system would produce. Not a bad return. 

When it comes to roof pitch, the optimal angle for solar panels in the UK falls between 30 and 40 degrees. This angle maximises sun exposure whilst allowing for some self-cleaning from rainwater, reducing maintenance needs. That said, solar panels can be installed on roofs with pitches ranging from 15 to 50 degrees with only a minimal impact on efficiency. So really, no matter what type or style of roof you’ve got, you can still install solar panels and they’ll generate electricity for you.

Different roof types require specific considerations during installation. For example, tile roofs may require the removal of some tiles and the installation of special brackets. Slate roofs need careful handling to prevent damage to the delicate slate tiles. Metal roofs, on the other hand, often allow for simpler installations with clamps that attach directly to the seams. 

Before going ahead with an install, it’s important to make sure your roof is in good condition. If your roof needs repair or replacement in the near future, it’s often more cost-effective to address these issues before installing solar panels. This approach prevents the need for removing and reinstalling the panels to perform roof maintenance, saving both time and money in the long run. Your solar panel installer should do a thorough roof inspection beforehand. 

Advantages of sloped roof installation:

• Maximises available unused space
• Often the most cost-effective installation option
• Generally requires minimal additional structural support
• Meets local planning requirements more easily than other options

Disadvantages of sloped roof installation:

• Dependent on existing roof orientation and condition
• Can be challenging to access for any maintenance required
• May require planning permission in conservation areas or for listed buildings
• Potential for roof leaks if not properly installed

Flat roof installation

For homes with flat roofs, solar panel installation is still very much possible. There are a few differences to keep in mind though.

Unlike on sloped roofs, panels on flat roofs need to be tilted at an angle, usually around 10-15 degrees. This makes sure they are better optimised for sun exposure and can self-clean with rainwater. 

Flat roofs have an advantage in that the angle and orientation can be set regardless of the building’s orientation. For example, you can arrange the solar panels in a southerly direction. 

To achieve a set angle and orientation, flat roof installations have to use a different type of mounting system. This tends to be either a ballasted system, which uses heavy weight to secure the panels in place, or a system that directly anchors to the roof structure. The choice often depends on the roof’s load-bearing capacity and wind conditions.

Maintenance considerations for flat roof installations include making sure there’s proper drainage to prevent water pooling around the panel mounts and regular checks of the mounting system’s integrity. It’s also important to keep the area around the panels clear to prevent shading from debris or plant growth. While these installations can often accommodate more panels than a sloped roof, they may have weight limitations depending on the roof’s structural capacity.

Advantages of flat roof installations:

• Panels can be oriented and tilted for maximum efficiency regardless of home orientation
• Easier access for maintenance and cleaning
• Can often accommodate more panels than a sloped roof

Disadvantages of flat roof installations:

• May require additional waterproofing measures to prevent leaks
• The tilted panels can be more visible from ground level
• Potentially higher installation costs due to the need for a mounting structure
• May have weight limitations depending on the roof’s structural capacity

Ground-mounted solar panels

For homeowners with plenty of outdoor space, ground-mounted solar panels present an interesting alternative to roof installations. A standard residential ground-mounted system might require 25-50 square metres of land, depending on the system size. This space needs to be free from shade and preferably on level ground.

Ground-mounted systems offer several benefits, including optimal placement for maximum sun exposure and easier access for cleaning and maintenance. They can also be scaled more easily than roof installations, allowing for future expansion if needed. The ability to set the perfect orientation and tilt angle can maximise energy production.

However, these systems do use up significant outdoor space and may be more visible, potentially affecting property aesthetics. Installation costs can be higher due to the need for groundworks and mounting structures. Find out more on ground mounted vs roof mounted solar panels.

Planning permission is more likely to be required for ground-mounted systems, especially if they’re visible from public areas. Always check with your local planning authority before going ahead. 

Advantages of ground-mounted solar panels:

• Allows for optimal orientation and tilt angle for maximum sun exposure
• Easier to access for cleaning and maintenance
• Can be scaled more easily than roof installations
• Doesn’t impact roof integrity

Disadvantages of ground-mounted solar panels:

• Uses up garden or usable outdoor space
• Potentially higher installation costs due to groundworks and mounting structures
• May be more vulnerable to damage
• Often more visible, which may affect property aesthetics

Balcony installations

For those who live in a flat or apartment – and don’t have their own roof space or garden area – it’s still possible to benefit from solar. 

For these scenarios, a common approach is to use balcony solar panels. There are two options here: 

• A portable solar set up with portable battery storage – these don’t require professional installation
• Vertical solar panels that can be attached to balcony railings – these are the same ones that can be installed on the side of a wall or gable end. These are connected to the mains and need professional installation. 

With space limited here, the capacity for electricity generation is much smaller. You can only fit one or two panels at the most. The angle and orientation can also mean that balcony panels often don’t come with a high power output. 

That said, they can still contribute to a home’s energy needs, especially when combined with energy-efficient practices and appliances. They also offer the advantage of using an otherwise unused space. 

However, balcony solar installations may face stricter planning restrictions. There might also be potential issues with building regulations or lease agreements in multi-occupancy buildings. 

Advantages of balcony solar panels:

• Suitable for apartments or flats with limited roof access
• Use an otherwise unused space
• Potentially easier installation process

Disadvantages of balcony solar panels:

• Usually less efficient than roof or ground installations
• Potential issues with building regulations or lease agreements in multi-occupancy buildings
• Limited capacity due to space constraints

Other unconventional placements for solar panels

Wherever there’s surface, you can potentially install solar panels. There are plenty of creative options to consider, whether you’ve already got panels on your standard roof or not. 

Why not consider these areas:

• Solar carports – These structures combine a carport with a solar panel roof, providing both vehicle shelter and energy generation. In fact, there’s now a law in France that requires all car parks with more than 80 spaces to install solar panels. 
• Shed or outbuilding roofs – If your home’s roof isn’t suitable, consider using the roof of a shed, garage or other outbuilding. This can be especially effective if the outbuilding has a more optimal orientation than the main house.
• Solar patio covers – These can provide shade for outdoor living areas whilst generating electricity – great way to combine functionality with energy production.

So, where should you put solar panels?

The best and most common choice is a roof installation. These are generally the most effective in terms of generating power, plus they are fully out of the way.

But if your roof isn’t available for whatever reason, you’ve got options at your disposal. Essentially all you need is some kind of level surface to install a mounting or bracket system, as well as your solar panels. 

Because solar panels are a long term investment, you should always get professional advice before making a decision. A qualified solar installer can assess your property, consider your energy needs and recommend the best placement options for your situation.