In recent years there has been a tendency for some solar panel distributors to suggest that bifacial modules can be used on both commercial and residential roof tops. Whether bifacial solar panels are right for your rooftop depends largely on your roof type and mounting method. While they can capture up to 30% more energy in ideal conditions, they are often not worth the extra cost for standard residential installations.
When to Use Bifacial Panels
Bifacial panels are most effective when they have space to
"breathe" and receive reflected light on their underside.
- Flat
Roofs with Tilt Racks: If you have a flat roof and use tilt frames to
angle the panels, the backside can capture reflected light.
- Highly
Reflective Surfaces: They perform best over white TPO membranes,
light-colored metal roofs, or in areas with frequent snow, which
can reflect up to 90% of sunlight.
- Limited Space: If you have a small roof and need to maximize every square foot of energy production, the small gains (5–10%) might be worth the investment.
When to Stick with Traditional (Monofacial) Panels
For most homeowners, traditional panels are the more
practical choice.
- Flush-Mounted
(Sloped) Roofs: If panels are installed only a few inches above the
roof, almost no light reaches the back, resulting in a small gain
of 0–2% at most.
- Dark
Shingles: Standard dark asphalt shingles have low reflectivity
(albedo), providing very little light for the rear side to capture.
- Budget-Conscious
Projects: Monofacial panels are typically 10–20% cheaper
upfront and easier to install.
Here is a summary of the features of bifacial and monofacial
modules:
|
Feature |
Bifacial Solar Panels |
Monofacial Solar Panels |
|
Best Surface |
Light-colored/reflective (White, Snow) |
Dark or non-reflective (Asphalt shingles) |
|
Installation |
Requires elevation/tilt for best results |
Flexible; can be flush-mounted |
|
Durability |
Often more robust (dual-glass design) |
Standard; single glass with polymer back |
|
Weight |
Heavier (requires strong roof support) |
Lighter and easier to handle |
|
Warranty |
Often longer (30 years) |
Standard (25 years) |
