Model step
DC flat derates
Module quality, light-induced degradation, light-soaking and mismatch derates
Inputs used: Module efficiency loss, LID loss factor, Light soaking gain (CIS/CIGS), Module mismatch: power loss at MPP, String voltage mismatch
What it is
Flat derates act on the DC power: the module quality (modules that produce more or less than their nameplate), the light-induced degradation of the first hours of operation, the light-soaking gain of CIS and CIGS modules, and the mismatch between modules and between strings. Their values are entered on the Losses tab, and the step has a single option.
Options
- Sequential flat derates: quality, light-induced degradation, light soaking and mismatch as flat fractions
References
- Dobos 2014, PVWatts Version 5 Manual, NREL/TP-6A20-62641
API
dc_losses.quality_loss, dc_losses.lid_loss, dc_losses.light_soaking_gain, dc_losses.module_mismatch_loss, dc_losses.string_mismatch_loss