Experiences on the Integration of Thin Film Photovoltaic Modules in a Mediterranean Greenhouse

Photovoltaic thin film modules are a suitable option for the integration of solar based energy generation systems in greenhouses, specifically in countries where, as Spain, the existence of favourable feed-in tariff for renewable energy sources serves to increase the yearly income of such a agricultural exploitations. This work describes the experience performed at the University of Almería where a 1000 m pilot installation has been built and monitored, allowing the analysis of key features of the system design (modules characteristics and structural integration), functionalities in terms of overall electricity injected into the grid as well as crop productivity in regard to a reference level. The installation consisted of dividing into two identical and contiguous greenhouse sections where one of the sections roof was equipped with a set of carefully designed thin film photovoltaic modules strips. Both sections were grown under similar conditions for a period of 6 months. Continuous monitoring of the power injected on the grid demonstrates the feasibility of such a systems when installed on a test greenhouse. In regard to greenhouse crop results, this work concludes the need for further research regarding the impact of optical properties changes to the roof related to the use of PV strips that reduce available photovoltaic active radiation (PAR light) for crops.