# Table 2 Performance modeling equations

Description Equation Notations Reference
Power output P(I′, T′) = I ′  × PSTC[1 + (t1 ×  ln (I′)) + (t2 × (ln(I′)2)) + (t3 × (T′)) + (t4 × (T′) × (ln(I′))) + (t5 × (T′) × (ln(I′)2)) + (t6 × (T′)2)] Where, t1 = − 0.046689, t2 = − 0.072844,
t3 = − 0.002262, t4 = 0.000276, t5 = 0.000159, and t6 = − 0.000006 are the standardized power coefficients, n = 23.37, and n* = 5.44 are the standardized temperature coefficients for CdTe PV technology.
Where I, I′, T′, TmTa, PSTC, V, P(I′, T′), E, and PR are the solar irradiance, effective solar irradiance, effective temperature, module temperature, ambient temperature, peak capacity, wind velocity, effective power output, energy, and performance ratio respectively.
(European Solar Test Installation of the Joint Research Centre; http://re.jrc.ec.europa.eu/pvgis/; ; ; ; ; ; , )
Effective solar irradiance $$I^{\prime }=\frac{I}{1000\ }$$
Effective temperature T ′  = Tm − 25
Module temperature $${T}_m={T}_a+\frac{I}{n+\left({n}^{\ast}\times V\right)}$$
Energy outputs E = [P(I′, T′) × Time]
Performance ratio $$PR=\left(\frac{E}{I^{\prime}\times {P}_{STC}}\right)\times 100$$ 