Pan-global, annualized determination of solar collector optimum tilt angle

The efficient utilization of solar energy necessitates the determination of optimum tilt angles for solar collectors. Here, we describe an explicit annualized, regression-based calculation of optimum tilt angle from horizontal a on due south-facing collectors in 30°N to 60°N latitude. Fixed optimum tilt angles throughout the seasons for latitudes between 30°N and 60°N were determined using measured monthly optimum angles from horizontal and the average diurnal peak sun hours by month. This methodology was then generalized to include pan-Global latitudes β. We show that: (a) the total energy collected still exceeds 97% of the theoretical maximum and (b), the optimum tilt angle is given by |α|=|(0.8818 β + 0.1320)| for due North/South azimuths.