Tilt Angle Adjustment for Incident Solar Energy Increase: A Case Study for Europe

The work presented in this paper aims to analyze the efficiency of using optimum tilt angles defined for several time intervals to maximize the incident solar irradiation on a certain surface deployed in Europe. Such a technique would improve the solar energy harvesting process, both for photovoltaic panels and solar thermal collectors, while not investing in the more expensive sun-tracking devices. The optimum tilt angles have been determined for the yearly, bi-annual, seasonal, and monthly time intervals, which were delimited on a calendar and astronomical base, respectively, considering multiple locations from Europe, and using various mathematical models based on empirical equations and solar irradiation estimation. The total incident solar irradiation provided by adjusting the tilt angle multiple times per year was calculated and compared to that obtained when using the yearly optimum tilt angle. The gains for each type of adjustment were investigated, and the monthly optimization of the tilt angle is obviously the most effective one, ensuring gains of up to 7%, depending on the considered latitude. Otherwise, an optimization twice per year, using the bi-annual optimum tilt angles determined for the astronomical-defined warm and cold seasons, would be the next best solution.

Automated summary

The efficiency of using optimal tilt angles for different time intervals to maximize solar irradiation in Europe was analyzed in this study. The technique improves solar energy harvesting without the need for expensive sun-tracking devices. Optimal tilt angles were determined for yearly, bi-annual, seasonal, and monthly intervals based on calendar and astronomical data. Comparisons were made between adjusting the tilt angle multiple times per year and using the yearly optimal tilt angle, with monthly optimization proving to be the most effective, providing gains of up to 7% depending on latitude. The next best solution was using bi-annual optimal tilt angles for the warm and cold seasons.