Sandia Modules |

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The Sandia Modules library stores coefficients used by the Sandia photovoltaic module performance model.
Parameter | Description | Units
Material | Cell material. Multi-crystalline silicon is mc-Si, single-crystal silicon is c-Si. See the table above for thin-film cell material abbreviations. | --
Series Cells | Number of cells in series per cell string. | --
Parallel Cells | Number of cell strings in parallel. | --
BVoco | Open circuit temperature coefficient | V/°C
MBVoc | Coefficient representing dependence of Bvoco on irradiance. Typically zero. | V/°C
Vintage | Year field measurement data were collected. | year
BVmpo | Temperature coefficient at module Vmp under reference conditions | V/°C
MBVmp | Coefficient representing dependence of Bvmpo on irradiance. Typically zero. | V/°C
AImp | Normalized maximum power temperature coefficient, calculated by dividing alpha by Impo. | 1/°C
AIsc | Normalized short circuit temperature coefficient, calculated by dividing alpha by Isco | 1/°C
N | Empirically determined factor, also called the "diode factor." | --
dTC | Temperature difference between the cell and module back surface under reference conditions. | °C
FD | Fraction of diffuse irradiance used by module. For flat-plate modules, FD=1; for CPV modules, FD=0; and for low-concentration modules, 0 < FD < 1. | --
Ixo | Current at module open circuit voltage of Voc / 2 under reference conditions. Defines one of the five points on the module's I-V curve. | --
Ixxo | Current at module open circuit voltage of (Voc + Vmp) / 2under reference conditions.Defines one of the five points on the module's I-V curve. | --
A0-4 | Empirically determined coefficients used in polynomial representation of solar spectral effects of daily air mass variation on Isc. | --
B1-5 | Empirically determined coefficients used in polynomial representation of optical effects of the angle of incidence (AOI) on Isc. | --
C0-5 | Empirically determined performance coefficients that relate Imp, Ix, and Ixx to effective irradiance. | --
a, b | Empirically-determined coefficients used in temperature correction calculations. | --