Research Article

An Algorithm to Determine the Optimum Tilt Angle of a Solar Panel from Global Horizontal Solar Radiation

Table 8

The average standard error of the mean (SEM) of the tilt angles and of the monthly average of the daily global solar radiation values of diffuse solar radiation, computed separately for summer months (solar declinations ) and for winter months (solar declinations and ) as a function of latitude (The correlation coefficient relative to winter months was computed excluding the values relative to the latitude of Stockholm).

Latitude (deg)Average values of SEM values
Summer monthsWinter months

32.950.300.441.010.91
37.960.640.572.010.59
41.900.820.711.500.82
48.851.260.752.150.58
51.532.020.922.330.46
59.281.961.44n.c.n.c.
Correlation coefficient 0.9560.9350.835−0.789