This routine empirically computes the module temperature from the air temperature, the wind speed, and the in-plane irradiation. This model uses two empirically-determined coefficients: a_t establishes the upper limit for module temperature at low wind speeds and high solar irradiance, b_t establishes the rate at which module temperature drops as wind speed increases.

 

Figure 34. Empirical Module Temperature Coefficients

 

 

Inputs

Outputs

 

1.) Compute the module temperature as a function of the available insolation, wind speed, and air temperature:

2.) Compute the cell temperature. This temperature difference is typically 2 to 3 °C for flat-plate modules in an open-rack mount at a reference irradiance G_Ref of 1000 W/m².

Reference

King, D. L., Kratochvil, J.A., Boyson, W.L., Photovoltaic Array Performance Model, Report SAND2004-3535, Sandia National Laboratories, Albuquerque, NM, September 1997.