Net Efficiency of a Parabolic Dish Concentrator

The article gives the overview of an in-house made parabolic dish concentrator. A system for continuous tracking of the sun throughout the day was based on a dual axis tracker, where a linear actuator for vertical tracking and a pair of gears for horizontal tracking were applied. The tracking system was equipped with DC electric motors, operated by microprocessor-based control system. Position of the concentrator was periodically and automatically adjusted to direct sunlight, based on the amount of light delivered to four photo sensitive diodes. The sun's solar energy, reflected from the surface of the dish to the receiver and transferred to recirculating water, was finally stored into the heat storage tank. In order to investigate the operational parameters and to determine the net efficiency of receiver of parabolic dish concentrator, initial measurements of the main working parameters were performed, and the results presented and elaborated.