Nimesh Katariya Albedo is the fraction of sunlight a surface reflects, expressed from 0 (absorbs everything) to 1 (reflects everything). PVsyst uses 0.20 as its default ground albedo, while fresh snow can exceed 0.8. Designers use measured or modelled albedo to estimate rear-side irradiance and bifacial gain in energy yield studies.
Albedo Values by Surface
| Surface | Albedo |
|---|---|
| Snow (fresh) | 0.70-0.85 |
| Snow (old) | 0.40-0.60 |
| White gravel | 0.25-0.35 |
| Sand (light) | 0.30-0.40 |
| Concrete (new) | 0.30 |
| Concrete (aged) | 0.20 |
| Tan TPO roof | 0.25-0.35 |
| Wet vegetation | 0.20 |
| Dry vegetation | 0.25 |
| Black EPDM | 0.05 |
| Dark asphalt | 0.05-0.10 |
| Water | 0.05-0.10 |
Design Decisions
For bifacial ground-mount projects, the choice of ground surface materially affects yield:
- White gravel: +5-8% bifacial gain vs. vegetation.
- Concrete pad: similar to gravel.
- Painted white surface: similar to gravel.
- Sand: +3-5% over vegetation in hot climates.
Surface treatment cost ($0.10-0.50/W) often pays back via 3-5% additional bifacial gain.
Key Takeaways
- Albedo is the ground reflectance, from 0.05 (asphalt) to 0.85 (snow).
- Critical input for bifacial gain calculation.
- Use monthly profile in PVsyst for accurate modeling.
- High-albedo surfaces (gravel, concrete, sand) boost bifacial gain 5-10%.
- Site-specific measurement preferred for bifacial bankable projects.
Related Reading
Albedo rarely gets analyzed on its own, it feeds directly into the bifacial gain and rear-side irradiance figures that show up in a project’s yield model. If you’re building that model, the PVsyst tracker yield study methodology walks through where the monthly albedo profile actually enters the simulation chain, and the broader question of which platform to run it in is covered in solar simulation software picks for 2026.
Because a wrong albedo assumption quietly understates or overstates bifacial gain, it also shows up as a swing factor in P50/P90/P99 yield report uncertainty, lenders scrutinize the ground-surface assumption for exactly this reason. On the design side, ground albedo works alongside GCR and DHI as one of the core irradiance-and-layout inputs our Solar 3D Pre-Design team validates before a bifacial ground-mount layout is locked.
Frequently Asked Questions
3 commonly searched questions about Albedo.
What are typical albedo values for solar sites?
How is albedo measured on a solar site?
Why does albedo matter for bifacial modules?
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