Bifacial solar panels have appeared on the market in recent years and offer some key differences to traditional mono-facial solar panels. As consumers, you need to know whether its worth it to invest in bifacial solar panel technology or whether your better off saving your money.
Bifacial solar panels can produce power from the top side and the underside of the solar panel. In order to create power from the underside of the solar panel, the manufacturer needs to replace the opaque polymer back sheet with a translucent material or glass. This allows reflected sunlight to reach the underside of the silicon solar cells.
For the panel to be able to produce a material amount of power, a good bifacial solar panel will also have contacts and busbars on the underside of the solar cells. Manufacturers can also use frameless technology to increase the amount of exposure to the underside of the panel.
To generate any material amount of additional power, bifacial solar panels must be installed on ground-mounts or tilt frames (with panels lifted up from the roof) above reflective material. Reflective material could be white stones or pebbles for a ground mounted project or a light metal for a roof. Studies show that bifacial solar panels that are flush-mounted to a roof line will not produce any noticeable power from the underside.
Advantages of Bifacial Solar Panels
Increased Solar Power Production: The main advantage that buyers hope to achieve with bifacial solar panels is greater solar power production per solar panel that is installed. Manufacturers claim that you can generate up to 30% more energy than a mono-facial solar panel. Studies show that the increase in energy is heavily dependent on how the solar panel array is designed.
Increased Durability: Many manufacturers will use a ‘dual-glass’ construction for bifacial technology. Normally solar panels will have a 3.2mm glass sheet on the front and an opaque polymer back sheet underneath the solar panels. A dual glass solar panel will typically have the solar cells sandwiched between two layers of 2mm sheets of glass. This is suggested to offer greater durability which can be observed as many bifacial solar panels in Australia come with longer performance warranties (often 30 years) with a slower degradation rate of the solar cells.
How Much Do Bifacial Solar Panels Cost?
There are many things that influence the cost of a solar panel. Typically for brands that have mono-facial and bifacial solar panels, the bifacial technology comes at a 10%-20% premium.
Compare solar quotes from experienced installers in your area.
Are Bifacial Solar Panels Worth It?
If you are looking at installing solar panels that are flush mounted to the roofline (as shown in the picture to the right) or the roof material is dark and not reflective – we can conclude that bifacial panels would not be worth it. There would be an additional cost for the bifacial solar panel technology with no real increase in yield or production.
When would it be worth it?
In a 2024 study completed by the Australian National University, they established that bifacial technology could generate between 5% and 23% more power than mono-facial solar panels depending on the tilt angle the panels were installed at and the reflectivity of the roof material.
The study showed the best roofing material was white metal and that the optimal tilt for the solar panels was 45 degrees. In practice, it is difficult to tilt panels beyond 20 to 25 degrees based on mount frame settings and council requirements.
Below we calculate the economic case for installing bifacial solar panels under a typical scenario of a 6.6kW solar system:
Uplift in solar power production
15%
Assumed white colorbond roof and panels at 25 degree angle
Increase in power per year
1,369 kWh
Assumes solar panels installed in Sydney facing north
Increase in annual savings
$253
Assumes 50% of solar power is self-consumed and electricity rate of 30c per kwh and feed in tariff of 7c per kWh
Increase in cost to install bifacial solar panels on tilt frames
$871
Tilt frames at $25 per panel for 15 panels and 10% extra cost on average 6.6kW price
Simple Payback Period
3.4 Years
Limitations of this payback period calculation
We acknowledge that for many residential roof spaces, using tilt frames can limit the number of panels that fit on the roof as you need to leave space between the roofs of panel to allow for shading. In many cases it might be cheaper to get more production by flush-mounting more panels to the roof
The yield increase has been estimated based on a study completed in the ACT. Outcomes for customers are likely to vary depending on their location across Australia and the differences between system design.
Dual-Glass Bifacial Solar Panels May Be More Susceptible to Hail Damage
One interesting finding from this years PV Evolutions Labs solar panel testing is that the monofacial solar panels with 3.2mm of glass on the front were much less likely to break than dual glass solar panels with 2mm of glass on either side of the solar cells.
The test fired different size pieces of frozen water (hail) at 290 different solar panels. For the largest hail diameter of 50mm, the glass broke on 89% of the dual glass bifacial solar panels, while only 40% of the glass broke for the mono-facial solar panels with 3.2mm front sheet of glass.
Hail damage is not usually covered under a solar panel product warranty but may be covered by your building insurance. These findings are an important buying consideration for homeowners in hail prone areas.
Conclusion: Its Only Worth It In Niche Circumstances
In good circumstances, the extra cost of buying bifacial solar panels and tilt frames could have a payback period of 3.4 years.
However, this requires that the roofing material is white or a light grey metal material and that the roof has sufficient space to cater to a tilt frame design. Tilt frames can sometimes trigger council approval requirements depending on your location. Additionally, it may be better for customers in hail prone areas to stick to mono-facial solar panels given they have greater protection against hail.
As a result, we believe that bifacial solar panels will likely be a niche application for rooftop solar projects.
Compare solar quotes from experienced installers in your area.
Jeff has consulted on over 20MW of commercial solar projects, ranging from SMEs to ASX top 100 companies. Jeff has also provided independent advice to 100s of residential solar, battery and EV charging customers across every state in Australia. He holds an MBA from the Australian Graduate School of Management and is an expert in business strategy and financial analysis.
