Evaluating year-round solar energy harvesting in semi-transparent PV-integrated greenhouses with roof and wall installation in an even-span design

• Walls achieved 0.22 kWh/m² on average, supplementing roof sections with 0.24 kWh/m². • SR and SW sections produced the highest yields, peaking at 0.47 and 0.19 kWh/m², respectively. • NW and NR generated minimal energy, averaging only 0.05 and 0.01 kWh/m² annually. • East and West walls provided consistent output, averaging 0.35 and 0.22 kWh/m². • SW generated 0.32 kWh/m² in winter, contrasting with only 0.04 kWh/m² in summer. Given the global drive toward sustainable agricultural practices, semi-transparent photovoltaic (STPV) technology offers a dual benefit of generating renewable energy while still permitting a portion of sunlight essential for plant growth. Unlike traditional photovoltaic installations limited to roof surfaces, this work investigates the innovative use of STPV panels on vertical wall surfaces to maximize solar harvesting. By conducting an hourly irradiance analysis for a full calendar year, we evaluated the solar energy potential of different greenhouse sections (roof and walls) in Qatar's climatic conditions. The results reveal a significant contribution from wall-mounted STPV installations, which generated 83.77 % of the total annual energy compared to roof-mounted systems. Among the walls, the East Wall (EW) contributed consistently, achieving an annual average of 0.35 kWh/m², while the South Wall (SW) and West Wall (WW) also provided meaningful outputs of 0.19 kWh/m² and 0.22 kWh/m² respectively. In contrast, the North Roof (NR) and North Wall (NW) sections demonstrated the lowest energy outputs, with annual averages of 0.01 kWh/m² and 0.05 kWh/m², underscoring limited solar access due to their orientation. Sensitivity analysis further indicated that panel efficiency plays a crucial role in energy generation, with potential production reaching 18,904 kWh annually at a 20 % efficiency rate, significantly higher than the baseline 7 % efficiency considered in this study.