A simple method for estimating solar irradiation on inclined surface at any location using data analysis techniques

Abstract

This paper proposes a simple method for estimating the monthly global hourly solar irradiation (GHSI) on an inclined surface at any location. The method employs simple analytical solar position and GHSI calculation models to calculate the Sun's position at any solar time and the GHSI in clear‐sky condition for both horizontal and inclined surfaces at any target location, respectively. Then, data analysis techniques are applied on the measured data of horizontal GHSI for 12 months of a selected year to calibrate the analytical GHSI calculation model and develop a weather factor model for considering the effects of indirect radiations (e.g. diffuse and reflected radiations) and weather influence. Finally, the estimated monthly‐average GHSI on any inclined surfaces can be obtained using the calibrated GHSI calculation model and the weather factor model. The method is simple and easy to use because only the location (latitude and longitude), azimuth and tilt angle of the inclined surface as well as the measured horizontal GHSI information at the location (commonly available from national weather agencies) are needed as input data. Using the real data measured at Taiwan's Hsiang‐Shan, An‐Nan, and Gen‐Shan weather observation stations, the method has been validated and demonstrated to have acceptable accuracy and reliability in this paper.

Key words:

• global hourly solar irradiation
• weather influence factor
• data analysis technique
• solar power generation

Notes

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