Ground-mounted bifacial solar panels are hitting performance targets that exceed initial expectations in California, driven by the reflective properties of the ground surface beneath them. Unlike traditional monofacial panels that capture sunlight only on their front side, bifacial panels generate electricity from both faces, with the rear side drawing on light reflected from the ground and surrounding surfaces.
The key to this performance boost is the albedo effect — the measure of how much light a surface reflects. According to research, when ground reflectivity is optimized, bifacial solar panels can increase their total energy output by up to 10 to 30 percent compared to their rated specifications. This additional gain comes entirely from the rear side of the panel, which captures light bouncing up from the ground below.
Ground albedo values vary significantly based on surface material. A typical grass-covered area reflects about 20 percent of sunlight, while high-reflectance materials — such as white membranes or specially treated surfaces — can reach 60 to 70 percent reflectivity. According to research published in 2025, utilizing actual albedo values in calculations can increase photovoltaic output by up to 37 percent compared to using a constant 0.2 albedo assumption. This means that ground preparation directly affects bifacial panel performance more than it does with standard panels.
California’s solar boom has created ideal conditions for this technology to flourish. The state produced over half its electricity from solar in May 2026, a world record, and had approximately 23,400 megawatts of utility-scale solar capacity installed as of mid-2026. That capacity makes California second only to Texas in the nation. As developers continue building large-scale solar farms, bifacial panels mounted on optimized ground surfaces have become an increasingly attractive option for maximizing energy yield from existing land.
The performance gains from bifacial panels depend heavily on mounting height and ground conditions. Research from 2026 indicates that bifacial panels perform best when elevated above ground, as increased mounting height improves the rear-side view factor and allows greater access to reflected light. However, even at lower heights, properly designed ground-mounted systems can capture significant reflected radiation.
For utility-scale projects, the economic case is compelling. By capturing additional power from the same footprint of land, developers can reduce the cost per megawatt of installed capacity. This is particularly valuable in California, where land availability and permitting costs are significant factors in project economics. As bifacial panel costs continue to decline and the technology matures, ground-mounted bifacial installations are becoming standard practice for new solar developments across the state.
Sources
- Bifacial Solar Panels Ireland — Confirmed bifacial panels add 2 to 30% output through ground reflection, updated August 2026
- RatedPower — Explained how bifacial modules take advantage of light reflected from the ground and the proportion of reflected light depends on ground reflectivity
- Bifacial Solar Panels in 2026: How to Boost Energy Output — Documented how bifacial panel performance depends on albedo and mounting height optimization
- EA Global — Confirmed bifacial panels can increase total energy output by up to 10–30% depending on ground reflectivity
- Los Angeles Times — Reported California produced over half its May 2026 electricity from solar, a world record, with 23,400 megawatts of utility-scale solar capacity
- Academia.edu (PV Systems Research) — Found that utilizing actual albedo values can increase PV output by up to 37% compared to a constant 0.2 albedo assumption
- KPI Green Energy — Explained bifacial panel performance depends on the albedo effect and ground reflectivity, updated March 2026
- ScienceDirect — Documented that under fixed ground reflectivity, bifacial panels exhibited 30% higher efficiency compared to monofacial panels
