Energy Analysis of Solar Home Lighting System With Microcontroller-Based Charge Controller

In this paper, a solar powered home lighting system in the Electrical Engineering Department of Visvesvaraya National Institute of Technology (VNIT), Nagpur is analyzed for energy using a personal computer simulation program with integrated circuit emphasis (circuit simulation software, PSpice 9.1). The home lighting system consists of a solar panel of 37 W_p, a 45 Ah battery, a solar charge controller, dc loads of two 9 W compact fluorescent lamps (CFLs), and a dc fan of 14 W. Through the solar panel, the battery is charged during day time. In the night, when solar power is not available, the battery provides power as a backup to the dc load consisting of two CFLs and a dc fan. The aim of the paper is to analyze the solar home lighting system for energy gain/loss with a microcontroller-based charge controller. From the analysis, it is concluded that the solar home lighting system is not designed for continuous energy gain as per manufacturer's specifications. The design needs to be modified to have energy gain in the system for Nagpur, India. A designed microcontroller-based charge controller is also analyzed. The advantages of a microcontroller 89C2051-based charge controller are its simple design, low cost, logic change facility with change of programming of microcontroller, presence of liquid crystal display (LCD) with battery charge status, and display of different messages. Ride software is used as an assembler for generating the required hex file of program and it is used for burning in the microcontroller IC with the help of Vegarobokit (a microcontroller programmer developer) to make a microcontroller programmer.