PV System Performance: Summary Simuation programs such as NREL’ SAM will calculate these performance factors and losses and present them in a graphic format as shown below.. | Other performance factors Performance Soiling Inverter Loss PID GHI to POA Low Irradiance Power Clipping Light Soaking Far Shading Temperature Wiring Loss Aging Inter-Shading Module Quality Transformer Power consumption IAM Mismatch Dispatch Summary