If the default overall DC to AC derate factor of 0.77 is not appropriate for your PV system, you may use this calculator to determine a new value by changing one or more of the component derate factors in the table. You may enter values within the ranges shown in the table. Values outside the ranges are reset to to the default values by the derate calculator. Click on HELP below the table for information about DC to AC derate factors.

Component Derate Factors	Component   Derate Values		Range of Acceptable Values
PV module nameplate DC rating			0.80 - 1.05
Inverter and Transformer			0.88 - 0.98
Mismatch			0.97 - 0.995
Diodes and connections			0.99 - 0.997
DC wiring			0.97 - 0.99
AC wiring			0.98 - 0.993
Soiling			0.30 - 0.995
System availability			0.00 - 0.995
Shading			0.00 - 1.00
Sun-tracking			0.95 - 1.00
Age			0.70 - 1.00
Overall DC to AC derate factor	0.77