Designing and implementation of energy-efficient wireless photovoltaic monitoring system

Photovoltaic (PV) cell usually shows unpredictable results due to abrupt change in environment. Environmental parameters such as temperature, dust factor, irradiance, and air mass have direct influence on the output of PV cells. Monitoring PV and its related environmental parameters is very important for understanding and analysis of PV in practical conditions. The PV parameters have been found useful in many ways like reliability analysis, life cycle costing, returns on investment calculation, loss of load probability, and optimal designing of PV power supplies. Currently, designed PV monitoring systems (PVMS) are reported to be expensive, complex, and are limited in their applications, out of which only few are wireless. In this article, we design and implement a simple cost-effective and wireless PV monitoring solution. The design PVMS is based on microcontrollers, light-dependent resistors, current sensor, analog-to-digital converter, solid state relays, ZigBee (XBee) wireless microcontroller, and LabVIEW-based data logging software. The designed PVMS performs the real-time analysis and data logging of open circuit voltage (V_oc), short circuit current (J_sc), ambient temperature (T_a), cell temperature (T_cell), and maximum power point. In addition, real-time I-V and P-V characterization of PV module is another valuable feature embedded in the designed PVMS.