Low-cost solar Radiation Sensing Transducer for Photovoltaic Systems

Measurements of solar irradiance are critical for evaluating solar energy potential in a given location and for calculating the efficiency of a solar system (Photovoltaic and solar thermal). In order to maximize the energy collected by a given Photovoltaic System tracking the position of the sun in order to expose a solar panel to the maximum radiation level at any given time is needed: to do so the maximum insulation direction must be determined. On this regard it is worth to investigate a low-cost solar radiation sensing transducer, which consists of a structure of green light emitting diodes: this device should be designed not only to individuate the direction corresponding to maximum insulation, in order to every timed expose the solar panel to maximum radiation, but also to measure the beam and the diffuse solar radiation. In this paper some preliminary experimental results regarding testing and calibration of a prototype developed in the Idrilab laboratory in Catania (Italy) are reported. Key-Words: Photovoltaic System, Tracking System, Solar Radiation, Diffuse solar radiation, Sensing transducer, low-cost.