Real time monitoring of solar fields with cost/revenue analysis of fault fixing

This paper proposes a monitoring approach based on single string real-time measurements. An electronic board was developed able to sense string voltage and string current along with open circuit voltage and short circuit current of a selected solar panel belonging to the string. Acquired information allowed real time monitoring of the power actually produced by each string. At the same time, information gained from the monitored solar panel allowed the definition of a production target which is dynamically compared with the actual value. Each string is both compared with stored data regarding the string itself, in order to identify performance degradation during time, and with all the other strings, in order to immediately identify an underperforming string. Experiments performed on a medium size solar field allowed the evaluation of energy losses attributable to underperforming strings. The conversion of energy losses into money losses can be adopted to quantify the revenues of fault fixing.