David Faiman presented a module temperature model (Faiman 2008) based on simple heat transfer concepts.  The model form is:

$T_{m}=T_{a}+\frac{E_{POA}}{U_{0}+U_{1}\times&space;WS}$

where

• $T_{m}$ is module temperature (°C)
• $T_{a}$ is ambient air temperature (°C)
• $E_{POA}$ is the irradiance incident on the plane of the module or array ($W/m^{2}$)
• $U_{0}$ is the constant heat transfer component ($W/m^{2}K$)
• $U_{1}$ is the convective heat transfer component ($W/m^{2}K$)
• $WS$ is wind speed (m/s)

In his paper, Faiman measured irradiance, wind speed, and module temperatures on seven different types of modules and fit the data to values of $U_{0}$ and $U_{1}$.  Note that all modules had front glass covers and Tedlar® backs.

• Values of $U_{0}$ varied from 23.5 to 26.5 with a combined fit = 25 $W/m^{2}K$
• Values of $U_{1}$ varied from 6.25 to 7.68 with a combined fit = 6.84 $W/m^{3}sK$