Solar technology has continued to develop in recent years, giving UK homeowners, businesses and commercial property owners more options when it comes to generating renewable electricity. One technology gaining increasing attention is bifacial solar panels UK.
Unlike traditional solar panels, which primarily generate electricity from sunlight hitting the front of the module, bifacial solar panels are designed to generate electricity from both the front and rear surfaces.
This means they can potentially capture additional sunlight that would otherwise go unused.
But how do bifacial solar panels work, and are they suitable for the UK's climate?
What Are Bifacial Solar Panels?
Bifacial solar panels are photovoltaic modules designed to generate electricity from sunlight reaching both sides of the panel.
The front of the module captures direct sunlight, while the rear can capture additional light reflected from the surrounding environment.
For example, sunlight can hit the ground beneath an elevated panel and reflect upwards towards the rear of the module. The solar cells can then convert some of this additional light into electricity.
Many bifacial modules use glass-glass construction or another transparent rear structure that allows light to reach the solar cells from behind.
How Do Bifacial Solar Panels Work?
The basic process is similar to that of conventional photovoltaic panels.
When sunlight reaches the solar cells, the cells convert the light into direct-current (DC) electricity. A solar inverter then converts the DC electricity into alternating-current (AC) electricity that can be used within a property or exported to the grid.
The difference is that bifacial solar panels can also make use of light reaching the rear of the module.
This additional rear-side generation is commonly referred to as bifacial gain.
The amount of bifacial gain depends on the installation and environmental conditions.
Why Is Bifacial Gain Important?
Bifacial gain refers to the additional electricity produced because the rear of the panel is also capable of generating energy.
The potential gain can be influenced by several factors, including:
- The reflectivity of the surface beneath the panels
- Panel height
- Panel spacing
- Tilt angle
- Orientation
- Shading
- Weather conditions
- The design of the solar module
This means that simply installing a bifacial panel does not guarantee a particular increase in electricity generation.
The surrounding environment and system design are extremely important.
Are Bifacial Solar Panels Suitable for the UK?
Yes, bifacial solar panels can be used in the UK.
The UK's relatively cloudy and changeable weather does not prevent bifacial modules from operating. Solar panels can generate electricity from both direct and diffuse sunlight, meaning they can continue producing energy even when the sky isn't completely clear.
However, the amount of additional rear-side generation will depend on how much useful light reaches the rear of the panels.
This makes the installation design particularly important in the UK.
How Does the UK Climate Affect Bifacial Panels?
The UK receives a mixture of direct and diffuse sunlight throughout the year.
While the UK generally receives less solar irradiation than some southern European countries, solar panels can still produce significant amounts of electricity.
For bifacial systems, diffuse light can also contribute to rear-side generation when conditions allow.
However, the actual energy yield will vary depending on location, season, orientation, shading and system design.
A system in southern England may have different annual generation characteristics from one in Scotland, for example.
The Importance of Surface Reflectivity
One of the most important considerations when installing bifacial solar panels is the surface underneath them.
A reflective surface can send additional light towards the rear of the modules.
Light-coloured surfaces generally reflect more sunlight than dark surfaces.
This can make ground-mounted systems particularly interesting because the ground conditions can influence the amount of reflected light available.
On a rooftop installation, the colour and characteristics of the roof can also affect rear-side generation.
Panel Height and Positioning
The distance between the panels and the surface underneath them can influence bifacial performance.
When panels are raised higher, there can be more opportunity for light to reach the rear of the module.
However, increasing the mounting height can also increase structural requirements and installation costs.
For this reason, the ideal panel height should be determined as part of the overall system design.
Bifacial Solar Panels for UK Homes
Bifacial solar panels can be installed on UK residential properties, but they may not always provide the same benefits as they would in a large ground-mounted installation.
Many residential solar panels are mounted relatively close to the roof surface.
If the rear of the module has very limited access to sunlight, the additional energy generation may be relatively small.
However, properties with suitable mounting arrangements and favourable roof conditions may still benefit from bifacial technology.
The suitability should therefore be assessed on an individual basis.
Bifacial Solar Panels for UK Businesses
Commercial and industrial properties can provide more opportunities for bifacial technology.
Large commercial rooftops may allow panels to be mounted with greater clearance, while solar carports can naturally provide plenty of space beneath the modules.
Ground-mounted commercial systems can also be designed specifically around bifacial performance.
For businesses with significant electricity consumption, additional solar generation could potentially help reduce reliance on electricity purchased from the grid.
Ground-Mounted Bifacial Solar Panels
Ground-mounted installations are one of the applications where bifacial solar panels can provide particularly strong potential.
Elevating the panels allows light to reach the rear, while the ground underneath can provide reflected sunlight.
System designers can consider:
- Ground reflectivity
- Panel height
- Row spacing
- Tilt
- Orientation
- Shading
- Vegetation
Careful design can help maximise the amount of useful light reaching the rear of the modules.
Bifacial Solar Panels and UK Solar Carports
Solar carports are another potentially suitable application.
Because the panels are elevated above vehicles and parking areas, there is space beneath the modules for light to reach the rear.
The surface below can also reflect sunlight upwards.
This can make bifacial technology particularly interesting for commercial car parks, shopping centres, workplaces and other locations with large parking areas.
Benefits of Bifacial Solar Panels in the UK
There are several potential advantages to using bifacial solar panels.
Additional Energy Generation
The rear of the module can capture additional light and potentially increase overall electricity production.
Better Use of Available Space
Bifacial panels can potentially produce more electricity from the same installation footprint.
Suitable for Large Installations
Ground-mounted systems, solar carports and commercial projects can provide favourable conditions for rear-side generation.
Durable Construction
Many bifacial panels use glass-glass construction, which can provide strong protection for the solar cells.
Long-Term Potential
When correctly installed, bifacial technology can contribute to long-term solar energy production over many years.
Are Bifacial Panels More Expensive?
Depending on the manufacturer and model, bifacial solar panels can cost more than some traditional monofacial panels.
The mounting system may also require additional consideration to take advantage of rear-side generation.
However, the initial purchase price shouldn't be the only consideration.
If the system produces additional electricity throughout its lifetime, the increased energy yield could potentially help offset the higher initial investment.
The important comparison is therefore the total system cost against expected lifetime energy generation.
What Should You Consider Before Choosing Bifacial Panels?
Before choosing bifacial solar panels for a UK installation, consider:
- Where will the panels be installed?
- How much light can reach the rear?
- What is the surface beneath the panels like?
- Can the panels be mounted with sufficient clearance?
- How much shading is present?
- Is the additional energy generation worth the additional cost?
- Is the panel compatible with the selected inverter and mounting system?
These factors can help determine whether bifacial technology is the right choice.
Bifacial Solar Panels UK: Are They Worth Considering?
Bifacial solar panels can be an attractive option for UK solar installations where the system is designed to take advantage of rear-side generation.
They can be particularly interesting for ground-mounted solar, solar carports and suitably designed commercial installations.
For standard residential rooftops, the benefits may be more limited if the panels are mounted very close to the roof.
Ultimately, bifacial technology isn't automatically better than conventional solar panels. The value depends on the specific installation and how effectively the system can utilise light reaching the rear of the modules.
Final Thoughts
Bifacial solar panels UK installations can provide an opportunity to increase solar energy generation by capturing sunlight from both sides of the module.
The UK's climate is not a barrier to using bifacial technology, but careful system design is essential. Panel height, surface reflectivity, spacing, shading, orientation and mounting structure can all influence the amount of additional energy generated.
For the right application, bifacial panels can be an effective way to maximise the electricity produced from a solar installation.
In the next article in this series, we'll compare bifacial solar panels in the UK with traditional monofacial panels and examine which technology is better suited to different UK installations.
