The electrical performance of a single-axis sun tracking agrivoltaic system inside a polytunnel greenhouse

Abstract

This study proposes a novel agrivoltaic tracking system integrated inside rather than above the greenhouse. The innovative single axis 6 kWp photovoltaic (PV) system integrated within a greenhouse is evaluated by analysing the influence of seasonal variations and environmental factors on energy output and performance from May to October. The system achieved a maximum output of 32 kWh per day in June, corresponding with a yield of 5.5 kWh/kWp, comparable to standard outdoor PV systems under similar Mediterranean conditions. However, performance inside the greenhouse was limited by global horizontal irradiance reductions due to greenhouse covers and seasonal dust accumulation. The tracking system demonstrated a 15–20% increase in output compared to a fixed system inside the greenhouse, a reduced effectiveness by structural and environmental limitations inside the greenhouse. Capacity factors were observed to be lower inside the greenhouse (0.18–0.19) compared to outdoor systems (0.20–0.24), reflecting challenges such as partial shading and diffuse irradiance. The performance ratio for the tracking system in July was relatively low (0.65) due to the fact it was inside the greenhouse. This study underscores the potential of agrivoltaic systems inside greenhouses to generate energy effectively while addressing the unique challenges posed by the greenhouse environment.