Grid Connected PV Systems in Dairy and Poultry Farms in Brazil: Evaluation of Different Installation Approaches

摘要

The aim of this paper is to evaluate three grid connected photovoltaic systems that were implemented in rural properties dedicated to the animal protein supply chain in the west of the State of Parana, Brazil. PV modules with mono and multicrystalline Si solar cells from the same supplier were used. One of the PV arrays was ground mounted, faced to North, 18° tilted and the others were mounted on the north-facing rooftop of the farm buildings. On the roof of a cow-shed, PV modules were 18° tilted, azimuth angle of 9° NE and on the roof of a poultry house, PV array was 13° tilled (same slope of the roof) and with an azimuth of 52° NE. Two inverter brands were applied and two approaches to connect to the electrical grid were used. The results indicated that high difference in performance ratio and yield can be produced due to the position of the inverter inside the farm (distance to the main electric input) and the installation approach. The highest performance ratio (PR) was obtained for rooftop mounted with optimum slope angle, reaching an annual PR of 86 %. This PV array installed in an approximately 8 m high cow-shed presented the lower operating temperatures due to the high wind speed on the roof. Concerning the module temperature, the higher PV module effective temperatures were observed in ground-mounted array, that achieved and annual PR of 82 %. The worst average PR obtained was 69 %, in a farm where the inverter is located near the PV array but far away from the main electrical panel.