Normal panel Vs. Bifacial panel front & rear side

[Shaojie]

Hello,

I did a test in order to understand bifacial panel front and rear side compare with normal panel.

DC: 180 pcs x 400Wp =72kWp

AC: 60kW

Panels are mount on a concrete wall vertically.

Ground Albedo: 0%

location: Singapore

PVsyst: V6.80

Simulation_A: Normal panel, tilt angle 90 deg, Azimuth 90 deg, Annual generation 40MWh,

Simulation_B: Bifacial panel, tilt angle 90 deg, Azimuth 90 deg, Annual generation 67MWh,

Simulation_C: Bifacial panel but front side facing wall, tilt angle 90 deg, Azimuth 90 deg, Annual generation 26MWh.

my question is, why the generation of B is so high compare with A, I thought they should be similar.

Best Regards

SJ