Feasibility study of using photovoltaic cells for a commercial hydroponic greenhouse: Energy analysis and life cycle assessment

Abstract

Today, the growing demand for hydroponic greenhouses is driven by the limitations of fertile land and water. In light of the imperative for sustainable development, particularly in energy usage within these greenhouses, the integration of clean energy sources, especially solar power, is essential. This study aims to assess the energy and environmental aspects, as well as the practicality of employing photovoltaic cells to meet the energy requirements of a commercial hydroponic greenhouse in Alborz province. Data was gathered from a 3000 m2 strawberry hydroponic greenhouse through on-site visits, surveys, and measurements. The findings revealed that the total input energy during a production period amounts to 8652.20 GJ ha−1. The energy ratio, net energy, and energy productivity were calculated as 0.03, -8424.20 GJ ha−1, and 0.20 kg GJ−1, respectively. Natural gas accounted for the highest input energy use, followed by electricity, while biocides, human labor, and chemical fertilizers had the lowest energy consumption. According to the LCA results, the damage categories for resources amount to 724.69 USD2013 per 1 ton of strawberries, with natural gas exerting the greatest impact on this measure. The feasibility assessment for solar energy implementation in the greenhouse indicated that approximately 120 m2 of solar cells would be required to generate electricity from solar radiation, covering about 4% of the greenhouse roof. Furthermore, the use of solar cells was found to enhance energy and environmental indicators.