using bi facial modules

[bahram]

for a 2 MW solar plant i am using PVsyst 7 with Bi facial pv 450 W and 110 Kw inverter the problem is the output power in comparison using 450 w mono PV is only 5-6% more while normally the output power must be at least 20% more .

i will be thank if any one has the same experience in this relation and explain to reach more power with using Bi facial modules .

B.R

B.hamzeh

[Bruno Wittmer]

The bifacial gain can vary through a wide range, from a few percent up to 20% or more.

A bifacial gain of 20% is quite high and can only be achieved in very special cases.

The additional generation that you can expect from using bifacial PV modules depends on several parameters, the most important ones being:

1. Albedo (the higher the albedo the higher the gain)
2. Pitch (the larger the pitch the higher the gain)
3. Mounting height (the higher the modules, the higher the gain

The albedo is most crucial and can range from 15-20% for surfaces with little reflection up to 80% for freshly fallen snow. You can find a table with typical albedo values in the PVsyst help.