Stand-alone LED lighting system powered by PV and battery: electrical overall performance analysis of a case study

In the present paper an innovative street lighting system with solar PV and battery as the source of electricity was monitored and analyzed considering a case study installed in Italy center. A Light Emitting Diode (LED) is used together with a dimmer control system. This application is new because high efficiency PV cells are applied to the cylindrical surface of the pole: monocrystalline cells have diodes able to bypass the cells that are not directly irradiated by sun to allow the best performance of the PV. The data of this solution were monitored for one year in terms of LED consumptions, current, voltage, PV power, and charging-discharging performance of the battery. These electricity parameters were hourly investigated considering different boundary conditions (weather parameters). These results allow to propose different optimization strategies in terms of scheduling and management of the system related to all the electrical components. The best sizing of the PV and the optimal scheduling profile were proposed based on the experimental and numerical analysis.