Optimization of Panel Spacing, Tilt Angle, and Azimuth Angle for Bifacial Panels with Fixed Land Acreage and Orientation for Several United States Locations

Date of Award


Degree Name

M.S. in Renewable and Clean Energy


Department of Mechanical and Aerospace Engineering


Advisor: Rydge Mulford


Bifacial solar photovoltaic modules generate electrical power on both sides of the panel, increasing energy output. Through more effective utilization of installed surface area, bifacial panels surpass the energy generation of monofacial panels per unit installed acreage. The performance of bifacial panels largely depends on their positioning relative to the sun. Therefore, bifacial panels require specific orientations to maximize energy production. The specific challenges of bifacial modules have sparked research into the ideal spacing and orientation of bifacial panels, considering geographic location, tilt angles, and solar energy production. The present study aims to pinpoint the most favorable tilt angles, azimuth angles, and panel row spacings for bifacial panels across various latitudes for a fixed array area and an adjustable array area. The core objective of this research is to maximize the electricity generated by bifacial solar panels. This involves creating a model that predicts power output for a specific location, accounting for variables like panel spacing, azimuth angle, average cell temperature, local ground reflection, and panel efficiency. The study also seeks to employ optimization to achieve peak annual power production. Methodologically, the study stratifies the solar panel array into zones, calculating the power generation capacity for a central panel in each zone. This includes factors like cell temperature, efficiency, and irradiance levels on both sides. Such calculations leverage Python APIs and packages for efficiency and accuracy. The computational model also factors in shadow effects, albedo, panel placement, and atmospheric conditions. To determine the optimal setup, the study adjusts variables such as panel tilt, azimuth angle, and spacing between panels using a differential evolution algorithm. The results reveal that optimal power production exists for bifacial panels with an associated optimal tilt angle, azimuth angle, and panel spacing. These results are presented for a fixed array size and orientation, where the number of panels adjusts as the azimuth is varied as well as for a fixed number of panels. For New Jersey, the power output is maximized with a spacing of 2.5 meters between panels set at a 33-degree tilt and facing an azimuth of 176 degrees. Similar results are presented for a variety of locations in the United States of America. In summary, for solar farms to use land efficiently while maximizing energy generation, it is critical to consider all influencing factors—such as spacing, tilt, azimuth, and panel efficiency—comprehensively.


Bifacial solar panels, Tilt angles, Azimuth angles, Panel row arrangement, Panel spacing, Maximum output, Optimizer

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